aoe eee 1 4 4 He i: + Hy eo ea ee CMS @\ APNE i a hr: yi ra Es eh Mth ae] at aban! iti ' iS ey yates atte ee es 2 hr peers nie ‘a ic val HMe peg hy ath ra Cs ietpeoiial dalon aa Lean Siemens va Ep , Heals Le teeesemir rie ile Pati ft Rise ee Heeea a eae fs Resa stier > nee aetoaicr om ae aioe sah evn setae ; pelentiatiee cer ror PL ey aes fae nay xi re Peay Mi oe e Mp nd ity (ae aa a ie hiss i Peis tieeeen eh Te corns i Hl i) Hd Mi a iy id Ri eh A, spss: iss ; EMEP otek rartelte hi ee pesicertin Pe eo nal tat) Ws Hts ee eS a te Pahac oe / eh oe hy 1 ne , a fait ey AN I Hue Pebble rat er a j Bit if ae a ii ie i om WR a uate i te ae a ant a — antes Hine miata pliehagenhd ss Piatt Ai nets tN af a tale CORNELL UNIVERSITY LIBRARY FROM | The Van Cleef Library ornell University Library Laboratory apparatus and reagents; select LABORATORY APPARATUS AND REAGENTS SELECTED FOR LABORATORIES OF CHEMISTRY, METALLURGY AND BIOLOGY IN THEIR APPLICATION TO EDUCATION, THE INDUSTRIES, MEDICINE AND THE PUBLIC SERVICES CaBLe ApprEss, ‘“‘ BALANCE,” PHILADELPHIA Copes: A.B. C., 5tH AND 6TH Ep., Marcont, AND BENTLEY IMPROVED | ARTHUR H. THOMAS COMPANY WEST WASHINGTON SQUARE PHILADELPHIA Le Se as INCORPORATED, STATE OF PENNSYLVANIA, 1900 EDITION OF 1921 COPYRIGHT 1921, BY ARTHUR H. THOMAS COMPANY HIS copyright protects all the copy- rightable component paris of the cata- logue, including the text and illustrations. Electrotypes of the woodcuts used in this catalogue are loaned, on request, to authors for tllustration of their text. Electrotypes of our wholesale specialties are furnished dealers for use (without mutilation) in the preparation of their catalogues. Electrotypes of all other items are made for our own use and are not loaned to dealers, nor is their reproduc- tion in any way without our authority permitted by us. PRINTED BY THE FRANKLIN PRINTING COMPANY, PHILADELPHIA-NEW YORK PREFACE PRICES—The prices in this catalogue are subject to change without notice and, with the exception of original package discounts indicated, are mostly net. In unity with the practice of some manufacturers, we also allow a special institutional discount to colleges and hospitals on Microscopes and accessories. Our prices are subject to daily control and on all trade-marked or branded items they are identical with those established by the manu- facturer. On all other items they are in accord with market conditions, being computed upon our net costs by means of definitely established formulae. Our prices are always identical on open orders and competitive pro- posals. Where time permits and exact advance information as to expenditure is required, we submit upon request an itemized Statement of Current Prices for the items selected. TERMS, DOMESTIC—Prices are f. 0. b. Philadelphia, boxing included except where otherwise specified in the catalogue and our terms of payment on open accounts are net cash thirty days from date of bill. Individual and commercial customers having no account with us, and regarding whom credit information is not readily ob- tainable through the usual channels, are requested to remit with order or send satisfactory credit references. TERMS, EXPORT—Prices are f. 0. b. Philadelphia, with special export packing charged extra at cost. Delivery is free alongside in overseas shipment where steamer sails from the port of Philadelphia. Payment for export shipments is preferred by means of a banker’s confirmed letter of credit in par New York funds, drawn in our favor on a Philadelphia or New York bank, available upon presentation of invoice and shipping documents. Where small amounts are involved, advance payment is suggested in par New York funds. To foreign firms and institutions whose credit and other responsibility are known to us or readily ascertainable in the U. S., we ship with draft at sight with documents attached for delivery against payment with interest and banker’s collection charges included. All terms of payment for export shipment are subject to change without notice because of war or political conditions. STOCK—All current items listed in this catalogue are carried in our own stock for immediate delivery with the exception of a very few items, of which prompt factory shipment is usually possible. The maintenance of so large and varied a stock is to be understood as subject to certain interruptions beyond our control in the way of manufacturer’s and transportation delays, strikes, war, etc. RETURN OF GOODS—Customers are requested not to return goods for any reason until after communi- cation is had with us. When the return is arranged, suitable tags are sent which, when attached_to the articles in question, insure prompt credit, repair or exchange, as indicated. The time involved in such preliminary ar- rangement is insignificant compared with the time and labor required to establish the identity and disposal of goods sent us without such precaution. BREAKAGE AND SHORTAGE—Although our shipments are checked and packed by experienced em- ployees under rigid control, breakages and shortages occasionally occur because of defective packing or of our mistakes. When such claims are clearly and promptly presented to us it is our custom to adjust them without undue argument, as we subordinate literal terms of contract to an underlying spirit of fairness and retain our interest in each transaction until our customer receives full satisfaction and value, no matter where or when our technical responsibility may end. We further assist in presenting established claims against the transportation companies from which we hold receipts for shipments. Customers will greatly facilitate the adjustment of such claims by refusing to receipt for goods received in damaged condition until they have been examined and con- dition noted by the local freight or express agent. SHIPMENTS— Where no instructions are furnished with order we exercise our own judgment as to method of shipment, i. e., via freight, express, boat, parcel post, etc. All shipments are made in accordance with the regulations of the Interstate Commerce Commission. All parcel post shipments are automatically insured against both loss and breakage under a blanket policy, the small charge for which is included on bills. AGENTS AND REPRESENTATIVES—We have no special agents or territorial representatives and all our traveling is done by members of our permanent staff in Philadelphia. Our wholesale specialties are obtainable throughout the world from regularly established and recognized dealers in laboratory apparatus. SPECIAL ORDER SERVICE—We maintain classified information and prices of many items required for laboratory work and not listed in this catalogue. This information is always available to our patrons upon request. Where it seems more desirable to purchase directly from the original source rather than through our medium, such recommendation is promptly offered. Philadelphia, U.S. A., September, 1921. III Ay AR Eb oR Ele Tt ‘Hy -O (Me oA US Cc O M P A N _ Y EXPORTATION OF LABORATORY APPARATUS see ee preparation of invoices and other documents as required by Customs illustrations below. No claim of re Pee Se ae see ee ee a pockigad by Ue. ge or loss in transit in export shipments has ever been meee ee work unfamiliar in pre-war years with our facilities for shown an increasing tendency to puRcaaEe: ci oe ee eee oe Ta SPR One Rog eat nae PTS 539 RP. BALE PAPAN DEL —— PAMORATORY UNACAO D1 EL of. MARAGAY 5 nee M. ADUANA. BRIKA KATANGA be a ( BELLO RA co. SANTA MARTA 76 DAROMEY 7 . = "109 11/4)! ALEADANAD | ( PTA 9 | MATACATIG Tee ree 2680 >, OFMDAY | STE The illustrations show the wide geographical extent of our ex i ich i ili ; t ] e i port business, which ¢ the thirty-four foreign steamship services operating out of Philadelphia and ae ee throughout the world. We deliver alongside all steamers sailing from Philadelphia, thereby effecting for Se se as stantial economies in lighterage and forwarders’ charges as compared with shipment through other American hare IV A R T H UR H. Ek Oo" Me AS G sO" MP A. NS OY EXPEDITIONARY LABORATORY OUTFITS _ The equipment of expeditionary laboratories involves careful selection of apparatus for more or less un- certain conditions of work, special packing to meet unusual conditions of both sea and inland transportation, and ample stock for immediate shipment. We acknowledge the valuable experience gained in the supplying of labora- oe aa to many hospital units equipped by the American Red Cross for the U. S. Army and for other nS DAS ( FRANCE The upper illustration shows the complete laboratory equipment of the Pennsylvania Hospital unit, U. 8. Army Base Hospital No. 10, as assembled, packed and delivered to steamer in four days. Many such equipments were supplied by us during the first year of the war. In every instance the officer in charge reported receipt of our shipments by the A. E. F. in France in perfect condition. ; The lower illustration is of a post-war expeditionary laboratory shipment under the direction of the Amer- ican Red Cross. This equipment was assembled, packed and delivered to steamer in five days. Vv AR T HH UR H. T H O M AS Cc O M P A N Y PARCEL POST SERVICE ; : Our insured parcel post service has developed to an extent beyond original expectations. It enables pa- fone ie secure quick delivery of many items of moderate bulk and weight without waiting for the preparation au s pe of larger lists of equipment. The efficiency of this service is greatly increased by our complete stock. any of our original stock packages (as shown on opposite page) have been designed to facilitate immediate shipment by parcel post. Domestic parcel post packages may not exceed 84 inches in length and girth combined. In measuring a par- cel the greatest distance in a straight line between the ends (but not around the parcel) is taken as its length, while the distance around the parcel at its thickest part is taken as its girth. The limit of weight is 70 lbs. for delivery within the first, second and third zones, and 50 lbs. for all other zones. As poisonous, explosive or corrosive articles are excluded from the parcel post, certain chemicals and reagents may not be sent by this means. Foreign parcel post is in operation between the U.S. and ninety-eight foreign countries and their depen- dencies. In this service the limit of weight is 11 lbs., with the greatest length within 3 ft. 6 in., and the greatest imit of length and girth combined within 6 ft. The upper illustration shows packages prepared for foreign parcel post delivery and the lower illustrates those for domestic parcel post delivery. VI Ao UR? OP oH Un oR: H. T H OF M A S Cc O M P A N _ Y ORIGINAL PACKAGES Prompt, accurate and economical service is much facilitated by the use of our original package quantities, or even multiples thereof, in the preparation of order lists. These packages also increase safety in shipment, con- venience in unpacking and in checking invoices and safe storage on laboratory or store-room shelves. In many instances shown throughout the catologue a discount is allowed for these original packages because of the econ- omies effected in our own handling. ‘easi79 SA CCA TIN, Banal ho Ko pl i Len0-a740 = TERT TUDES Gua, | [RMX it nat = funrnmmiecc! (e280) SAS 27H FERREMTATION TURES Metric quantity specifications for items listed and packed on the dozen basis, and vice versa, result in un- necessary delay in shipment and tend to retard, rather than advance, the universal adoption of the metric system in commerce and trade. We favor the use of the metric system wherever practicable, but encounter many difficul- ties in the way of its rapid adoption because of the use of automatic machines for the making of standard cartons _ and boxes, and long established practice in trades other than those connected with the Laboratory Apparatus business and finally, because of many items which pack better by dozens than by tens. For example, certain articles pack in a carton of satisfactory shape in three rows of four, rather than in one row of ten or two rows of five pieces. VII Ei UR H. T H O M AS Cc O M P HE merchandise listed in this catalogue originates in some 1200 different establishments. Our selection is based upon thirty years of experience in the supply of apparatus and reagents to chemical, metallurgical and bio- logical laboratories and has been made with painstaking care. The various items are described and illustrated without exaggeration and with as much discussion and illustration of underlying principles and details of construction as are necessary for wise selection. The name of the author, with full reference to his publications bearing on the item in question, is given where such data is likely to be of value. Many important assortments, such as lamp-blown glass- ware, volumetric glassware, rubber tubing, rubber stoppers, sheet-metal ware, hardware, wooden ware, etc., are made from our own designs and specifications and bear our name only. Such items are superior in accuracy, appearance and durability to the ordinary trade article. In some instances our prices on these goods are higher than for the usual quality, while in others they are lower because of the quan- tities for which we are able to contract. We list many articles under the manufacturer’s name, and, while these manufacturers are primarily responsible for the design and performance of their apparatus, we take full responsibility—having exercised no little discrimination in our selection—for all such trade-marked or branded items in this catalogue. VIII SPECIAL NOTICE Philadelphia, U. S. A. N August 5, 1914, we announced that our prices would not be advanced because of scarcity or unusual demand, but only when our own stocks were obtained at increased costs. This policy was conscientiously adhered to by us during the whole period of advancing markets. Now that markets are declining, we are, as lower cost merchandise becomes dependably available, reducing our prices in accordance therewith, irrespective of losses involved because of stocks on hand purchased at higher costs. Some pronounced reductions in our prices on many important items, partic- ularly lamp-blown and volumetric glassware, have been put into effect since the forms were closed for the pages of this catalog. ARTHUR H. THOMAS COMPANY November 21, 1921 5M 11-21 1018 : to absorb diffi- ae 1.60 130 160 15 1.05 0 2800 0 220 5 3.95 4000 8000 .85 1.30 neter of mouth eam ee 8.35 180 200 25 30 .35 45 180 200 25 30 35 45 Balance 18.35 1015. Air Pump, Vacuum and Pressure, of brass, nickel plated. Mounted on oak base, with chamber 16 inches long by 23 inches diameter. With two valves and two nipples for inlet and outlet of air.... 16.00 1018. Air Pump, Mercury Vapor, of Pyrex glass, operating on the injector effect of a vapor column. This pump produces a vacuum of 0.1 to 0.001 mm. It evacuates a 2 liter vessel from 15 to 1 mm in two min- utes; to 0.1 mm in five minutes; and to 0.01 mm or less in twelve minutes. As it pumps vapors as well as gases, it is recommended for distillations, for use as a fore-pump to a high vacuum pump of the ‘‘condensation”’ type, etc. With directions for use............... 1 40.00 A R T H UR H Te 3H? “O* =Mir A. 3S Cc O M P A N Y eae“ ? a is) | 1020 1024 1020. Air Pump, Geryk. The pistons work in oil, which follows and seals the inlets and outlets so that leakage isimpossible. With a pump plate of plate glass 10 inches diameter, cemented in the base. The air opening in the center of the pump plate is fitted with a safety plug which prevents the entrance of mercury and other undesirable substances, while permitting the free passage of air, and there is also another opening at the side of the base for attachment of pressure gauges, etc. The piston is 12 inches diameter, with a 33 inch stroke, and is operated by a hand wheel. A vacuum of 0.15 mm may: bevobtained: ain. 5 paki ertn Oe-egcocinn sue teens Ae PCM grain Geter UGA CALA A oh ertee ALAS 75.00 Oil, for use in lubricating air pump cylinder, and for use in oil sealed pumps such as No. 1020. Per APPIN CA cag cans Rea es anes eee eae een ee roe a Seca ny ete aeclsns gael a ORI Ge Me erNE se -30 AIR PUMP, LANGMUIR CONDENSATION. This pump contains no moving parts, but depends simply upon a blast of mercury vapor which pushes the gas which is being removed into a condenser, where the mercury is condensed for use over again, and where the gas is carried away to the atmosphere by means of a mercury pump. When connected up with tubing large enough to allow efficient operation, it works at a rate of 3000 to 4000 ml per second, otherwise as low as 10-+ bar (one bar being equal to a pressure of 0.00075 mm of mercury or about one-millionth of an atmosphere). In theory there is no lower limit (other than zero) below which the pressure cannot be reduced. In practice, however, the continuous liberation of gas from glass walls or metal parts makes it extremely difficult to obtain vacua in excess of the above amount. In operation, the Langmuir Condensation Pump requires an auxiliary or backing pump capable of pro- ducing a vacuum of at least 0.10 mm of mercury. For thoroughly satisfactory operation, the back pressure should be well below 0.05 mm of mercury. The two-stage pump listed below is perhaps the most satisfactory for this urpose. Dire See: Langmuir, “The Condensation Pump: an Improved Form of High-Vacuum Pump,” General Electric Review, December, 1916; Dushman, “The Production and Measurement of High Vacua,” General Electric Review, beginning June, 1920. This series of articles gives valuable suggestions regarding exhaust procedure, and is now being published in book form by the General Electric Review. 1022. Air Pump, Langmuir Condensation, as above described, with mercury, glass connection tube, vacuum grease and electric heater for 110 volts............ 0.0... cece eee eee 120.00 1023. Air Pump, G. E. Two-Stage; an oil sealed mechanical auxiliary pump developed especially for use with the Langmuir Condensation Pump. Produces a vacuum of 0.001 mm of mercury; capacity 1.4 cu. ft. of free air per minute. The pump is submerged in oil and will exhaust a 5 liter vessel to 0.5 mm of mercury in one minute, to 0.007 mm in five minutes and to 0.0017 mm in ten minutes. Care must be taken that no mercury vapor is allowed to enter the backing pump, or brass and babbit parts will be attacked. When complete outfit is supplied a mercury trap shown in the illustration and filled with broken glass to give additional condensing surface is furnished for use between the Langmuir and the backing pump. With 8-inch diameter, crowned pulley, for operation at 325 TaD ETM nos Src Ne UTM AL pce a Ne Pea on relia staan Ge eae eat a rare Rae Barut Dene as Ae 368.00 1024. Complete Outfit, consisting of Langmuir Condensation Pump, and G. E. Two-Stage Auxiliary Pump, and 4 h.p. motor directly connected through a gear and pinion with the auxiliary pump, all mounted on same base as shown in illustration. For 110 volt d.c.........0...000.00.. 570.50 1025. ditto, but for 110 volt, 60 cycle, single phase a.c.......... 6... eee eee 585.00 2 A R T H U_ R H. T H O M A 5S Cc O M P A N_ Y 1029 _ , AIR PUMP, CENCO HYVAC. A self-contained high vacuum pump, producing of itself without any preliminary or backing pump a vacuum of 0.001 mm or more. By the new construction an old principle in pump design—that of a solid cylinder mounted on a shaft so as to rotate eccentrically within a larger hollow cyl- inder—has been so improved as to obviate the necessity of a preliminary or backing pump. This is accomplished by means of two stages mounted vertically at a slight angle to each other, with the rotors mounted on a common shaft. The stages are securely attached to one vertical side of a square cast iron case, with removable lid through which passes the inlet tube. The pump is entirely immersed in a carefully selected oil which effectually seals every surface and pre- vents any leakage. This oil bath serves further to distribute any heat generated by the rotor, and thereby pre- vents displacement of the parts through expansion. The general specifications are as follows: Degree of vacuum, mm.. Deane Shs ous 0.001 Power required to operate, h.p.............--- 1/12 Capacity in cu. in. of free air per minute... ‘ 415 Proper speed of operation, r.p.m.........--.-- 240 Size of pump, inches... ae 4144 x6% Size of pulley, inches.................-+005- 7 Size of wooden base, inches................-45 9x18 Weight of pump only, lbs..............-..--- 1614 Amount of oil required, ozs...........-.-.--- 21 1028. Air Pump, Cenco Hyvac, provided with automatic trap and with 7-inch pulley grooved for 3 inch round belt. Complete with supply of oil especially selected for high vacuum work; but without base OT TL OE OT ees tac cen hg EE OA AUS Se Fae ERS AS NR AONES eR PI ANE eh MPS Me SEE fey en ge GON Rs 50.00 1029. ditto, but mounted on base, with motor, cord and plug for lamp socket. For110voltd.c........ 89.00 1030. ditto, ‘ a bears 7 SREP PER tyae NA oo For 110 volt,60 cycle,a.c. 90.00 1032—Small ROTARY AIR PUMP AND BLOWER, CENCO, for producing a blast for the operation of blast lamps and for use with other laboratory devices requiring moderate air pressure or vacuum. The blowers are of small size, very compact and with few parts. They are free from mechanical troubles and require practically no atten- tion except an occasional oiling. They are mounted on a cast-iron base, directly connected to a constant speed motor of generous size, and are provided with a valve on the outlet tube, by means of which the air pressure can be varied. The outer casing of the blower is water jacketed so that the heat developed by compression during continuous use may be removed. ie ag su SE hop acelin a Dibra a SST CIR ne Rg Tone he Ghee hee a iegurealtre Sap ee Uae rate te Small Large Size of base, inches..... Sntadce : Spine on noncner niente Rab Aint eemhe, . Doral 13 x 734 Speed, r.p.m.......-...-. Ee ORES Re é ane BAe inte ake Ridial ee ea a an Re A aah es ‘ 1725 1725 Pressure at maximum speed, lbs. per sq. in. ‘ ADE ene Bee tne eas Aes BTR Ema teed Aa Annes % 10 Cubic feet of air per minute Lat MEAT RAW parte Rt eS neh hes a aes We ac AD PS Aa 0.75 1.4 Number of blast lamps... . tastes 2 4 Vacuum at maximum speed 16 18 Power consumption, Watts 5 Ce Be Ie ey dl RT Steen ea a ere 8 La 66 175 Motors i Dintscscdi-cieugnerdcunce ac saeree Soe eara Ma clvete Poe Reb tet Sel Oiars ARGO Goh aeRO wide aia i 1032. Rotary Air Pump and Blower, as above described, for 110 volt d.c..............0.. 47.00 61.00 1033. ditto, but for 110 volt a.c......... cegctayssa Mibesis MeseaAelan eli caatt annets.uais aliivers by Wee Glact som 50.00 67.00 1034. “ "without base or motor, but with pulley............-...05 cee ee eee ee eee 15.00 20.00 1036 1038 CROWELL TYPE A ROTARY AIR PUMP, for both Vacuum and Pressure (Crowell Positive Pressure Blower), for all purposes requiring air under pressure of from 1 to 10 lbs. to the square inch, or any degree of vacuum not exceeding 24 inches. The principle of construction is that of an internal drum and shaft carrying the sliding blades or pistons which operate in close contact with cylinder wall. No springs, gears, valves or unbalanced parts are used, and the action is simple and positive even at lowest speeds. The pressure is not de- pendent upon high speeds or centrifugal force. For laboratory work an air receiver is not usually required except where close regulation of pressure is desired. These are listed under No. 1050. IZOD OT eae ge as Uae Pips thd cock enna AU ah Me ewer et acter dayne cha eane nan rene 1-A 2-A Free air capacity, cu. in. per revolution... ........... 00.00. c cece cess 20 45 Free air capacity, cu. ft. per minute at maximum speed................... 6.9 13 Maximum-speed.irspame cos 255.28 ven sca doc anaes aa ee nea dns Wie Nec oun bab iue 600 500 Approximate h.p. at 3 lbs. pressure.....0.0.0000 00.00 cc cece cece eee $ a Bulleys;“In@Westn sors. Ae Ceres cys toast. 4 tens Olaaen uneecuuraae, op oa) aia eed a 4x1 4x14 Pipersize;-nletvand SGutle tives car duc cunslon ater duets patie as en neh avian sm ae 3 3 Approximate:net-welght, Ibs: : oo << ohne an whee oe ees Le heb! 24 84 HIG ORES PA COATT CSiy. cave ov te Betis Sin ue et ene ie RE TA clea Munley Alas Seater nary 10 x 64 1234 x 64 1036. Air Pump, Crowell Type A Rotary, as above described, without air receiver, or motor. 28.00 36.00 1038. Air Pump, Crowell Type O-D Rotary, for both Vacuum and Pressure, designed for intermittent opera- tion, and principally for vacuum work, but can also be used for pressure. When fitted in an oil immersion box, it is practically leak proof, and will exhaust to a vacuum of from 29 to 30 inches, or a pressure up to 25 lbs. per square inch. Capacity about 2 cu. ft. of free air per minute. Inlet and outlet tapped for 3 inch pipe size. About } h.p. is required to operate this pump, which has a speed of 600 r.p.m. Can be used either with or without the oil box. Weight with oil box 50 lbs. net, and without oil box 20 lbs. Floor space required for pump in box 15 x 8 inches. Without oil TEMIM GEST OM DOR A esol cule oe aces 2 oan seh vary oe Heimuk eeanuane Nb ee ati amram Se. CoOL OO: “ ‘ a Hi i i) 1040 1040. Air Pump, Crowell Type O-D Rotary, tor both Vacuum and Pressure, as above described, complete with oil immersion box.... ... Soe eD LUMEN 2 shapes a gst Ml UNG Wa neraneris CUOMO a A ac Gupta eh ye Gy 66.00 CROWELL TYPE D ROTARY AIR PUMPS, for both Vacuum and Pressure, with a working pressure of 25 lbs. or less to the square inch, and when used as a vacuum pump will exhaust to a vacuum of from 29 to 30 inches (mercury column) under permissible atmospheric conditions. The action is simple, positive and durable, with a continuous intake and delivery of the air, and no valves, springs, gears or unbalanced parts are used or required in the construction. This pump rotates in one direction only, either for use as a compressor or a vacuum pump, requiring no changes in the lubricating system, which operates from the outlet or pressure side under either compression or vacuum. Connections should be made to either the inlet or suction side for vacuum work, and it is also advisable, when using the pump as a compressor, to run a pipe from the inlet to a place where a clean supply of air is assured. The heads are provided with water jackets for cooling when necessary, and the flow of water is regulated by the valve which is fitted to the overflow or discharge pipe. (Continued on page 5.) 4 1042 CROWELL TYPE D ROTARY AIR PUMPS (Continued) N Y An air receiver is not usually required for laboratory work, except where close regulation of pressure is desired. These are listed under No. 1050. DIZEMUMbeR Metro. Seat nove epee 28 BM ook ead sie OAR 1-D 2-D Free air capacity, cu. in. per revolution....................... 15 40 Free air capacity, cu. ft. per minute at maximum speed......... 4.3 9.2 Maximum speed) Pp injec s5 sae ahwaehsceen beer e bie oc ne. 500 400 Approximate h.p. at 15 lbs. pressure, or 29 inches vacuum....... a if Tight and loose pulleys, inches....................00000.-.0.. 6x2 8x2 Pipe size, inlet and outlet............000.0..000000 0.000000. 3 a Approximate net weight, lbs.........0..00...00...00..0022... 70 115 PIG ORS Paces lit CES Nii siemens Me aise ate Sree es co a 13 x 18 14 x 22 1042. Air Pump, Crowell Type D Rotary, as above described, without air receiver, or motor........... Se Mente oe ne Mig eterna | cee an ere nn i 78.00 95.00 1044 4-D 280 40.5 250 4 14x4 1; 425 23 x 38 220.00 Crowell Type D Rotary Air Pumps, for both Vacuum and Pressure, exactly same as preceding, but mounted on special bedplate, and connected by silent chain drive with motor. The motors for a.c. are the repulsion induc- tion type, suitable for use on either 110 or 220 volt, 60 cycle, 3 phase current. Without Air Receiver (which is listed separately under No. 1050), but with motor. SIZEuIUM DER cs sar ttnehee Oa dona monte nh oak Seana Gh nee St auaa pant Sean taatia anlowte Saas 1-D SETS Peake amhctes teal erie PO an edt ee Ae tec ler teeth ec mA eA et Ae ete Ce tee a 3 1044. Each; with:motor:tor V0 voltidies. os coe cseuc rs Becta hs eee tis 6 tel don dietastns 304.75 1045. re ne ae “110 or 220 volt, 60 cycle, 3 phase, a.c................ 296.00 5 2-D 1 366.40 328.00 Air Receiver, for use with Crowell Rotary Pumps, Types A and D, as listed on preceding pages. Con- venient in laboratory use for accurate regulation of pressure, as the relief valve supplied with receiver can be set to blow off at any desired pressure. For suitable vacuum or pressure gauges to be used in connection with this receiver, see Nos. 6056 and 6057. Sizemumbersicrs nese cece Hauck cama emia tah ams Cantos 1 1 2 2 For use with Crowell Air Pump, Type.................. 1-A 1-D 2-A 2-D Dimensions; Inches’... 3 s¢cccnc0-0 see eea oh eee eee eae es 12x8 12x8 12x8 12x8 Capacity. -gallonss.cy.4, cis fase a cuvces areaanarahG aes 2.6 2.6 2.6 2.6 Pipe size, inlet and outlet........................0008., 3 4 3 3 1050. Air Receiver, as above described, with relief valve........ 12.00 12.00 12.00 12.00 1052. Air Pump Plate, of heavy plate glass 25 cm in diameter, ground plane and firmly cemented in a low form tripod base of iron. The base is cast in one piece to minimize danger of leakage and provided with brass stopcock and brass connecting tube with oil sealed taps for inlet or air, and for manometer. The vent hole at the center is tapped (75-16) for air pump accessories, and provided with a UAC Bern oy. tele else cca boat aes Ga kta ot aeabrttr a hea Nene aren aty tre sae oS ECR mney Re OREN 17.50 1054. Vacuum Gauge, MacLeod, for measuring high vacua, range from 0.02 mm to 0.00001 mm of mercury; capacity of bulb 500 ml; 750 ml of mercury is required for usewith this gauge. Mounted on wooden stand. With directions for use but without mercury........... 0.0.00 e cece eee 60.00 AIR SAMPLING APPARATUS, Palmer Water Spray Type, with motor. Equipment consists of a glass bulb collecting bow] with tubular elongations at each end through which air is drawn by means of a small blower connected with the upper end of the bulb. The lower end of the bulb is U-shaped in form, to form a reservoir for holding the proper amount of distilled water used for collecting the dust from the air. In the connecting tubing between the top of the collecting bowl and the blower is a suitable air Venturi meter for use in measuring the rate at which the air is drawn through the bowl by means of the blower. The rate of flow of air in cubic feet per minute is indicated on a suitable manometer and scale. As the air is exhausted from the collecting bowl by means of the blower, the water is displaced from the U tube, and on reaching the bulb enlargement it breaks into a fine shower. The force of the stream of air keeps the water in constant spray formation and the air is thus washed of its suspended dust as it passes through this spray of water. Thus, the air washer provides a very intimate contact between the air and the water, and gives assurance that no large bubbles of air will pass through without the dust particles being separated from the air and retained by the solution, The irregular shape of the glass tube forming the upper end of the collecting bowl eliminates the possibility of drops of water being carried out of the bulb. See: “A Study of Methods for Determining Air Dustiness,” by Palmer, Coleman and Ward, American Journal of Public Health, VI, 10, and ‘Final Report of the Committee on Standard Methods for the Examination of Air,” American Public Health Association, 1916. 1056. Air Sampling Apparatus, as above described, with motor.............. 0.00... cece eee eee. 200.00 Our illustrations and descriptive texts are mostly exact and always without exaggeration, with such discussion and illustration of principles involved and details of construction as may facilitate intelligent selection. A R T H U_R H. T H O M A § Cc O M P A N Y 1061 1063 1061. Alkalimeter, Schroedter, for determination of CO.; without tube in flask eae cape svi eee a avai tis 3.50 1062. ditto;;but-withstubbe-instlas kes tanner ne eaamesneta Wed cone a eae nn ental tenth Ante 5.00 1063. Alkalimeter, Geissler, for determination of CO.; with ground JOINS Weiss kde een Se actrees 7.00 1064. dittosbutenew. sf Ohmi aneyat ania bien: eee heh ner tnan chet odin net CNG NS nee nena ee alee 7.00 1065. Alkalimeter, Knorr’s, for the determination of absorption of CO, in inorganic carbonates, with ground glass joints, and with extra flask with ground glass neck............ 00.0000 ccc ce ce eeee 12.00 Alundum Tubing, of Mixture RA98, from 3 to 6 inches bore, for use in furnaces, etc. Because of the variety in diameter, length, etc., it is not possible to carry this tubing in stock. Supplied on special order only. Ammeters, see Voltmeters and Ammeters, page 606. 1070. [Ampoules, of hard glass of low alkali content. With flat bottom and with neck drawn to a point and sealed. Capacity sarily ine sa ake ae, Seacoast Seer 1 2 5 10 25 Per 100 3 be chee eie sah ha ana arene 1.50 1.50 2.50 4.35 8.10 20% discount in cases containing........... 2000 2000 1600 1200 1200 1071. ditto, but with open wide neck, as used in the distribution and administration of various vaccines prepared at the U. S. Army Medical School. Capacitysamly.uc ccc 4am cheese 1 2 5 10 25 PerslO0 sis ede ie as Pies encnesae stone tease 1.50 1.50 2.50 4.35 8.10 20% discount in case containing............ 2000 2000 1600 1200 1200 Note—Russell, Nichols and Stimmel, Military Surgeon, 1920, 47, p. 539, have found that the reaction of typhoid vaccine may vary considerably when held in soft glass containers at room temperature because of the soluble alkaliin the soft glass tubing. We do not, therefore, sell or recommend ampoules made of ordinary soft glass tubing. Ampoule Filler, see page 273. i Ho UR H. T H O M A S$ iC) Or Mii asPe «Av EN oY sayy Lex ol2 LW 1076 1076. 1078. 1079. 1080. 1082. 1083. 1084. 1086. 1087. 1088. th) i : cg Uae ae ST 0. ey 1082 Anaerobic Culture Apparatus, Biichner, consisting of a Test Tube 210 x 27 mm with a No. 5 rubber stop- per. In the use of this apparatus 2 grams of Pyrogallic Acid is placed in the bottom of the test tube under a wad of absorbent cotton, in which state the tubes may be stored in a dark place. When an anaerobic culture is to be made the tube is filled about one-third full of KOH solution and the culture tube containing the inoculating material placed quickly in position and the rubber stopper tightly inserted. Price includes test tube and rubber stopper only................. 18 Anaerobic Culture Apparatus, McLeod, consisting of two parts, a porcelain capsule to contain the pyro- gallic acid and caustic soda solutions and a special Petri dish which has its free margin turned inwards and upwards. The porcelain dish is a hollow chamber. It is bisected in the lower two- thirds of its depth by a vertical partition and there is a circular aperture in the center of its upper surface. Around the margin of the upper surface is a small groove which is filled with plasticine. In using the apparatus 5 ml to 7 ml of a 15% solution of pyrogallic acid is run into the compart- ment of the chamber marked A in Fig. 2. This can most easily be done with a large pipette; 5 ml to 7 ml of a 10% solution of caustic potash is then introduced into compartment B. The Petri dish is then pressed down into the plasticine in the groove and the plasticine is pushed up against its outer margin to insure the proper sealing of the chamber. Assoon as the access of fresh oxygen from without has thus been cut off, a mixture of the pyrogallic acid and caustic potash solutions is effected by tilting the porcelain dish so that the solutions run over the partition at the point K in Fig. 2 and react with one another. The Petri dish is shown in Fig. 1 ready for use in contact with the plasticine. Any condensation water which may form is retained in the groove R. See Journal of Pathology and Bacteriology (British), Vol. 4, April 1913, p. 454. Complete with both porcelain. dishvand:special Petridish ys wath ne es tea oe te idee ete ha otras bd Gl Ranch asa 3.50 Porcelain: Capsule; Onis ee neta Cees eee tnd hos Ge bie ae aL) a ican By hivaet eer done 1.50 Special: Petri: Dish; omlyc o2ce< 4 alse 8 ate toh, Oh ie ee ocean ano at rast gas) Ska hae patra arene 2.00 Note.—For Plasticine see Reagent Section. Anaerobic Culture Apparatus, Novy Improved, for the culture of anaerobic bacteria by either vacuum, gas or pyrogallate methods. The construction differs from the original Novy Apparatus in that the stopcock is placed above the stopper, thus relieving the large stopper from pressure and per- mitting the use of the vacuum method. Dimensions of lower chamber 150 mm high by 140 mm diameter. Complete with two iron clamps............ 06.02 eee eeeeee 7.25 ditto, but-glass: parts only; without-clampsi.. oo jet ae en cnn oes Rig ay a eintinan Tees ... 6.00 Iron Clamps, only, for Novy Anaerobic Culture Apparatus, as shown in illustration. Per pair..... 1.50 Anaerobic Culture Apparatus, Smillie, consisting of No. 6262 museum jar 12 x 5 inches, with two holes in the lid. Into one hole is fitted a bent stopcock with rubber tubing and glass tube for the sodium hydrate, and into the other is fitted a similar stopcock tube for the hydrogen, with a perforated glass tube containing platinized asbestos. The method depends on the catalytic action of platin- ized asbestos upon oxygen and hydrogen, and because the oxygen is completely removed, it is of great value to successful cultivation of anaerobes. See New Anaerobic Methods, The Journal of Experimental Medicine, 26, 59: (July) 1917. Complete apparatus as shown in illustration. 11.35 Stopcock Tube, for Sodium Hydrate, or for Hydrogen................. 00.0. c eee eee 3.00 Perforated Glass Bulb, containing platinized asbestos.... 0.00.0... 00.0000 00 e 1.60 with the exception of a very few items of which prompt factory shipment is usually possible. | All current items listed in this catalogue are carried in our own stock for immediate delivery, | The maintenance of so large and varied a stock is to be understood as subject to certain | interruptions beyond our control in the way of manufacturers’ and transportation delays, strikes, war, etc. AUR: Tso UR H. T H O M A 5S Ge 709 2M) SPAS IN, oy |_il ai 1092 1093 1092. Anemometer (Airmeter), for the measurement of air currents through mines, tunnels, sewers and in the ventilation shafts of hospitals, schools and other public buildings. : With four dials, zero setting adjustment, and jeweled bearings, in leather carrying case. With certificate. Best London TUL ace cecedeo tend Gace p aes eens ee cian neers te a unin A oie ana ti a dtecae eve Seaan Neat Ueanne tea onic ay anna act sy nea 48.75 1093. Anemometer, Biram Pattern, with four dials reading to 100,000 feet, zero setting adjustment, and jeweled bearings, in leather carrying case. With certificate. Best London make................. 47.50 an i i | | il | | il Hy Mt } | i Ani i ! i (hit ANTE HAR Wa ia iH . / | | ii i a | 1100 1104 1099 1099. Animal Balance, Decimal. A convenient and sensitive balance for weighing animals in laboratory work. With tare weight to compensate for the animal pan, so that the balance can be used for other pur- poses. Capacity 20 kilos. Without WEIGH US irs teew ind vntihd dan ween dinriniaeaseorine cheer ince ees 20.00 . Animal Balance, Troemner, with scale graduated in the metric system from 1 gram to 20 kilos. Fitted aay ia a removable galvanized iron box and tare weight so that with these removed the scale may be used for ordinary weighing. Size of box: 18x 12% 12 in¢hesias sawn e. ate water gk oes 81.90 1102. Animal Board, of wood, with hooks in each corner. Very convenient for animal experiments. Small size intended for guinea pigs and rats, and the larger size for cats, small dogs, etc. Size, MCHC cy ec or ogee pena SA Oe Vem Na Demet ee ES RRA NTE he es 12x8 25x12 3.20 6.40 i d, Latapie, total length 34 inches, total width 11 inches, with board of % inch solid oak. ae an the boas is placed on the table the top surface is approximately 3 inches high. Clamps are of solid brass, heavily nickel plated. These clamps carry rigid clamps underneath, and when these are closed the grip is positive ........ 6... e eee eee cece tent t eens 50.00 A R T H U_ R H. ede Or ocM A> 8 C O M P A N Y A Z ! C4 q REE REL! RCE Tre Te ul oe Hl pas 1114 1106. Animal Cage, extra heavy, of galvanized iron. The smaller size is suitable for rabbits, guinea pigs, etc., and the larger size for cats, small dogs, etc. With removable drawer, feeding trough, etc. Height,tin ches! ss cca ica needa crac ar a eer maa aoa eats Mies cued Na Eg oe 12 18 Teeneth) inches cx xcs a5 ions clens oak sugsnd aid aaetite toes tasadgel ois Satna a ook coe nah om ae 16 24 Widthiesin hese -acen tia rthiua44 eo cucc te eas kthens, tye aiapastoeih slens tay cn isoe Satan aatiaee an eet 12 16 Be Tact sat a eke otro reg EN UNC LE hey een IS 27.50 38.50 1108. Animal Cage, Heim. Designed specially as a breeding cage for mice, with two compartments, etc. Of wood with metal fittings, 20 x 12 x 12 inches.......... 0.0... 2 cc eee 22.00 1110. Animal Cage, with removable floor and conical drain for collection of urine. Of heavy galvanized iron wire, size 20 x 16 x 8 inches, height over all 19 inches. Size is suitable for guinea pigs, rats or rabbits Seco de Page tensa hove crenata cine RIALS sam aaRek SAU aca ulel eo fay chee ate ipe-spok aa lop swell Pore oun fori pavaas dead uses es 22.00 1112. Animal Gage, Phipps Institute Model, as designed by Dr. Paul A. Lewis. Of heavy galvanized sheet iron. The new feature of these cages is the arrangement for bolting together the units in stacks of two, four, etc., asshown in illustration. Height 14 inches, length 14 inches, width 16 inches.. 7.50 10% discount in lots of 6. 15% discount in lots of 12. 1113. Supports only, for No. 1112 Cage; 6} in. high, CaCI Siar ap ech eared 5 tears Mirgacn ate elit enna 1.75 1114. Animal Cage, Vaughan. Collapsible for convenience in sterilization or storage, the sides, top and bottom being in separate parts. Height (not including legs) 12 inches, total height 17 inches, length OO0nches, width, 15 inches: ..uaks aesensuas ye seen recite las Gane me iG Mot cre Seis esas ake eue 13.20 Animal Cages, for large animals and for special purposes are furnished on special order only. Prices and specifications on application. 10 1116. 1118. 1120. 1122. 1127. 1128. 1127 Animal Holder, for mice. Made entirely of metal, with adjustable clamp for holding the tail of the animal and slot in the upper part of the conical wire cage to permit of holding the mouse on its back for abdominal! inoculations xcs.5 ety doo dere 3 eecc casio gan Ses haes amaseae aaah eeeerd Sul Sena fin tn eatin Saale hea Fuaeie 5.00 Animal Holder, Voge, for guinea pigs. Useful for inoculating, taking temperatures, etc. Of zinc. SIZES INCHES wa teat cota aus AiG eet res ep ata ee ae aM ae ie Seen ease aS Fate ak ae ee dd eit Tx2k 8x3} CIV ey een eee hans etna te, Meee Oe hea Fea coh ca oR aceon ec AS 2.20 2.50 Animal Head Holder, adjustable. The middle bar of the mouthpiece has a half-inch hole through the center for the passage of a stomach tube. The curved pieces which pass above and below the jaws are clamped tightly around the mouth and locked by means of the set screw in the end of the UPPeTCULVEds PIECES, se. soc. ie oe a Seales aaa Rlbcdaten Aol bi deat Raed dunn taht atbtoas unpetiee -osdeaiecavins 10.00 Animal Jars. The smaller sizes are intended for mice, and the larger sizes for guinea pigs and rabbits. Tops are made of heavy galvanized wire with weight. The same jars may be fitted with closely fitting tops of mosquito and flea-proof gauze at an additional price. For prices of jars only, see Aquaria No. 1174. Height: Inches?) 27. ke ive weeasive teeta tice deel re ee 5 8 103 15 Diameter 1M CheSics 3.0 vhiate dh sceus es then eed sale vy Sisev Dreuseeneateta 6 83 11 16 CU eid ee Se ON ey HINER ee Re eee Eee 3.00 4.25 8.00 24.75 Animal Table, Brodie, with top 51 x 18 inches, fitted with cleats around the side into which the holding- down cords can be easily fixed. Near the center and flush with the top is a copper hot plate 30 x 12 inches which is heated by two incandescent lamps, each on an independent switch. Two upright rods sliding in slots are provided. With Brodie’s Anesthetic Bottle and Air Warmer No. 8110 attached and a bent tube projecting from the top to supply air to the animal. An animal holder, four controlling switches and plug adapter are included. With lamps for 110-volt ELT CULL ees ke ca acento a ee OS PIRES Ta aS Hee ena Uy aaa Ny erento ae 120.00 Animal Tags, of aluminum, as used for attaching to the ears of animals used in laboratory experimenta- tion. These are numbered consecutively from 1 to 500, and are sold only in packages of 100 con- secutive numbers, as for instance, 1 to 100, 100 to 200, ete. Each tag is fitted with staples for attaching to the animal’s ear. Per package of 100.................0 0.0 c cece eee eee 3.25 11 1140. 1141. 1150. 1152. 1154. 1160. 1162. 1170. 1172. ; ASL 1170 cAVNNS Annealing Cups, Denver Fire Clay Company’s make; of fine, white selected clay; largely used for silica 1160, 1162 fusions. INamibers earns ote ht ceo eA PN lat ae ahead ee S 0 1 2 SIZEsaINCheStarce 4 ainier ermine stan cise Soom nar teumrac estes eon 1¢x1% 1ix1} 14x13 POE GOZO, 0354 Hal d ers ee ee Ot eS Cee eRe eta SE ; 2.55 2.55 2.55 Covers for above Annealing Cups, per dozen..................... -75 .75 .75 Anvil, steel with polished face 17 x 4 inch, length over all 3 inches, weight 6 ozs.................. 1.25 Anvil, steel, with square, mirror-polished face. Size of face, inches......... 1 13 2 PACH ee cartes eer teen tne A Daan GR Prenat Galore Ahn ea ASn eC An DREN does 70 90 1.25 Anvils, with vise. A well-made tool, very convenient in the laboratory. Widthcolvjaws,anchesvircus mou, me maciewew duce as ara paler ma sah enene 13 2 25 Weights lbs newest nch iced Rn aOR tetccen ieumtn nconel cryonics 1s 4h gi PACH peat cacao reer aes eee Pah cn wine tra Rene AEN aN ea EE) Beir 2.50 3.55 4.85 Aprons, Laboratory, of pure black rubber cloth, both acid and waterproof. Very flexible and of light weight; can be rolled and crushed into small space for storing in drawer without damage. SIZE eit en eeepc ict touche yet std meus, Artis a RNA hoe ctat ene __ Small Large Dimensions; inches........ 5. s6. 43.04 e046 ve cetaceans 25 wide by 36 long 36 wide by 46 long LAC eset avy aera era eck Saas eB EM 1.00 2.00 10% discount in lots of 1 dozen. Oversleeves, of the same material as the laboratory aprons.............. 0.0.0.0. 0c cece eee -60 10% discount in lots of 1 dozen. Aquaria, oblong, of glass. Capacity Gallons: ciscc ga ein nia ein ohare tae aead Clan tees Movies Hides Muu rhea ad pines 24 5 eng th eniGhes oa ccc cecte se ceerp estuaries ne a tad a Pm ewe cheer ae a ee ys 103 13 AVA GLE sin COSI fen S sre rae ceed isasdse ace Atel 9 Ae costes vacate Pts cdc ae ATEN Cates A cas ln 63 8 Reig hits in Chesiga aap 5 seis se ncn eens 23g ena eRe ema 9 auinsrae ence etme A 103 13 PAG Nise fica cert earn ota se ee erate eainnnciat tele octane Nha Do A weenie Seen a 5.00 11.00 Aquaria, rectangular, of plate glass set in wrought iron frame, with slate bottom. As furnished by us to the laboratories of the U. S. Bureau of Fisheries. Tpenlothis in Chests. isa teen aneeiae tae ea nck one art neers URL 18 20 22 Wardtlay in CHES gos ogo sags ees re apt alee co haces ee eg eee 2 eed 10 12 14 Meio be inches: en ek ils Salt ht oe tel an maces bank tala! On Wie el aes 11 12 13 ACH Gi Geto esac es cc eats eRe eae ptiy engaure aun amet Aap et 15.00 16.50 19.00 1174. 1176. 1178. 1180. 1182. 1184. 1186. 1188. 1190. 1192. 1194. A S Cc O M P A N Y yg yA A a 1186 1190 1194 Aquaria, High Form, of glass, with heavy welted rim. Capacity -eallOnsien. cence cccwaa sae oe ema ee : 4 1 13 2 4 12 FRCL PH GSIN CHES ence eects ie astos Rercasd eee ee pe 5 6 8 8 103 15 Diameter, inches....... ed BM dnt ea ec uele thc? 6 7 83 9 11 16 Each, boxing included....................... 1.45 1.95 3.15 3.50 5.75 17.50 10% discount in case containing.............. 15 10 9 4 2 ditto, but low form. Capacity, gallons n000: 42 e635 ehee anaes i 1 2 3 43 7 10 Height, inches... ..c.cc¢ cee meee es 43 5 t 7% 84 gt 103 Diameter, inches.................... ca 8 10 12 14 16 18 Each, boxing included............... 1.75 2.25 2.75 3.50 5.25 7.40 10.80 10°% discount in case containing...... 18 12 6 4 2 2 Arsenic Apparatus, Gutzeit Improved, for arsenic tests, according to U. S. Pharmacopoeia, constructed entirely of glass with ground joints. The funnel tube permits the addition of reagents and the solution to be tested at intervals, enabling the operator to control the gas evolution and prevent VOLE Workers es ve ie treet dE Me ee te ane eins oa a Metre atone era Vs eee eran p 10.00 Arsenic Apparatus. A simple and improved form of the Gutzeit method, as used in the Food Investigation Laboratory, Bureau of Chemistry, U. S. Dept. of Agriculture. See W. D. Collins, The Journal of 5 Industrial & Engineering Chemistry, 10: 5, 362 (1918)... 0000. ll Arsenic Tubes, of Pyrex glass. Form............- 0.00000 ee eee A B aC Hr eee ea Neste ate ees er etd te Ea Neri Ronen nan ath Ae Dee tt Berean a chara ea eae dt ess 10 10 20% discount in lots of 100. Arsenic Tube, of Pyrex glass; with constriction. Total length 15 inches... . saad sneha semen ne .90 Arsenic Tube, of transparent silica, 3 inches long x 7 inch diameter, with bulb § inch diameter... 1.20 Asbestos Board, in mill size sheets, 42 x 48 inches. The board is carried in stock in the following thick- nesses for which approximate weights are given. On small orders, particularly when shipped alone, necessary crating is charged extra at cost because of the small value of the article itself. “ i 3 J Thickness, IMCs guise secs eee ees a ay 3s 1 a8 4 3 2 Weigh til b sig, cers trunnn sear mt cc cag ten Mesa 2 4 7 10 13 18 24 35 Per Ib., crating extra...............-- .20 .20 .20 .20 20 -20 -20 .20 Asbestos Board, in squares, for use under beakers, dishes, etc. Thickness; inches. .-:4..n.eer4css th haa ened eee a tees ds ds ds Size. INCHES: aie esceeny eee R ok base Phare ee a AGI Ath otene incite ba Ge deendand led & 4 5 6 Bee Hi eee i vets ectiestac AAA pe ah ee mth a ee hi 25 .30 .35 20% discount in lots of 100. Asbestos Cord, with strong, hard-twisted strands; convenient in the laboratory for supporting retorts, crucibles, etc., in contact with fire or heat. Diameter, inchess. 62.0 ser cass pe pee et IE No ates qe a 1 3 Poe) Mie palle Gg. nev ersaey ate ie Pe ameinee ite nae aM 1.00 1.00 1.00 Asbestos Gloves, with four fingers and thumb and gauntlet. Per pair. ....................... 6.00 13 R YY H UR H. Cy OS MPA IN, 1196. 1197. 1198. 1199. 1200. 1201. 1202. 1203. Zot on eon" 1196 1197 1198 Asbestos Mat, circular, 8§ inches in diameter, so-called ‘‘stove mats,’”’ with metal binding and ring for hanging up; very convenient in the laboratory... .........000 0c eee e eee ccc cceceeeeeee. 10 Asbestos Mats, square, } inch thick, neatly bound with metal to prevent fraying at the edges. Very convenient for use on table top and under burners to prevent scorching of wood, etc. Size,‘inches..........00.00000. 82x 88 11x11 9x14 15x15 14x 24 24 x 30 AGHA cist caere cent tie eet ats .30 35 -40 .60 1.00 2.25 Asbestos Pad, as used in Gasoline Distillation Outfit. Size 5 by 5 inches, with a 1} inch hole...... .16 Asbestos Paper, of pure, white fibre, 36 inches wide. Cut to any length. Perlb................. 55 1201 ASPHALT, ROAD OIL AND TAR-TESTING APPARATUS. Equipment for the testing of refined oils is listed under Oil Testing Apparatus, page 451. Penetrometer, Standard, New York Testing Laboratory Type, for measuring the depth of penetration of a standard needle into the material to be tested at 77° F or 25° C in 5 seconds of time under a 100 gram weight, with two needles, and standard clock reading in } seconds with dial graduated to 7; mm. A set of adjustable weights is provided permitting the use of either 50 or 100 gram loads in addition to the standard of 100 grams. See Richardson, The Modern Asphalt Pave- DOUG 5 Sara os eas sla lace eh a,b SENSE Cairn SEE atta AOR ERG Coe EPA PIR TTD SS AS. SreLELS. Eon OE ERE MUS HER Om a 110.00 ditto, but with magnetic clock which automatically operates for penetrations of 1, 5 or 60 seconds, thus eliminating all personal equation in the determinations. For operation with six dry cells. Wiathoutdiny cells. focus tected Ke site ne old null Nabe ae ee ta Oe uc Bhs cottons ce eins laneumte es 275.00 Penetrometer, Miniature, exactly same as No. 1200, but one half the size and specially designed for engineers’ portable use in making comparative tests, without clock...................... 55.00 Needles, for either Standard or Miniature Penetrometers. GEO ZO MNeapi cece rsicesas tes eww rise tee eeepc econ cose av hee VELL a TE NSDL ERASERS ra clatoa ast te pa vee 6.00 A, Ro Tf cH UP CR He TE UH OMA eS C O M P A NY 1222 1224 1226 1206. Penetrometer, Humboldt. A new model of improved construction with dial graduated in 100 divisions of 7; mmeach. The indicator works automatically and gives absolutely correct readings... 85.00 ) 1208. Drying Oven, New York Testing Laboratory Type, for uniform temperatures, with fan in bottom and 10-inch ring burner; of copper with asbestos jacket, 20 inches high by 11 inches diameter... 45.00 1210. Asphalt Flow Plate and Mould, consisting of 3 plates each with four corrugations and one mould... 10.00 1212. Asphalt Viscosimeter, New York Testing Laboratory Type, consisting of a concave aluminum float with three standardized brass plugs; for testing the consistency or the fluidity of bituminous binders UCU HE a cto te ara eae aaee Neca eae ee ome Og ah seu paragon cue tae pes 10.00 1213. Standardized Brass Plug, only, for Asphalt Viscosimeter..............0. 00.00. 2.25 1214: “Collar; only; for Asphalt-Viscosimeter®. os hos Se aes Seg ely Deke Ae gee Se ee sae 1.50 Oil Testing Apparatus. For testing the viscosity of bituminous compounds, such as oils, or of asphaltic material at high temperatures, 7. ¢., about 200° F, the Engler Viscosimeter is mostly used. See page 458. 1218: “Briqiette: Moulds.for asphalt... s544tern ion whens ct lad wa plein ine aa Lae ee Wee Ree ts 7.00 1220. Cubical Brass Mould, with plate for melting point determination, } inch........................ 6.00 4.65 1222. Bitumen Holder, Draper model..............-. 50000 eee eee 1224. Crucible, Porcelain, of special shape for bitumen determination, with perforated bottom and large filter- ing surface. Diameter at top 45 mm, diameter at bottom 35 mm, height 24 mm. Fits Filter Mabe NO. Do AeSiZerA 0 MMM ods soe nts ens eco onettns huqnt nd ON a atia ne aed Geant ara onmicoee nena wie .60 1226. Ductility Machine, Smith, for hand power. This machine is built in a stone trough, heavily painted with enamel paint both inside and out. All working parts are of brass, and arrangement is provided for three briquettes. For 110 cm pull. The test is conducted at 77° F, at a standard speed of 5 em per minute 64 clicks. The clicking device is usually synchronized with a metronome set fOr 64. beats: Der MINULE Leena a alte dy caus tte Kein xc eeetot er Asst Buona ielS dala mee arpresara Nels ManeahAck 280.00 Y 1228 1228. Extractor, New York Testing Laboratory Type, for analysis of paving mixtures containing broken stone. The bituminous mixture should be warmed until it can be readily broken apart by hand, with- out fracturing any of the stony particles; 500 grams of the disintegrated mixture should be packed as tightly as possible in the wire basket and then covered with a disc of cotton or felt of + inch to 4 inch thickness; 175 to 200 ml of carbon disulphide, carbon tetrachloride, chloroform or ben- zole is placed in the inside vessel in which the wire basket is suspended. Cool water should be circulated through the inverted cone condenser, which is also the cover of the apparatus and not intended to fit tight. A 16 c.p. carbon filament incandescent lamp is the source of heat. A 500- gpl IVIL y eu it gram sample of the mixture should extract clean with carbon disulphide in about 3 hours. From 200 to 300 grams of asphalt block or Topeka type mixture is a sufficiently large sample for that type of mixture. After extraction, the solvent and matter removed from the sample during the analysis should be burnt to recover any fine mineral particles which may have passed into the extract. These extractors are made entirely of metal. Complete with wooden base and 16 c.p. carbon filament lamp with porcelain socket. For 110 volts................... 00. e eee 60.00 ic (i | a =. | { [ hh il | hii N 1230 DULIN ROTAREX, designed for determining bituminous aggregates, and adapted for bitulithic, macadam or ordinary surface mixtures. : These machines are equipped with specially constructed vertical type motors that will operate on either alternating or direct current. A heavy fly wheel is attached to the motor shaft. This has the effect of balancing the load and consequently reducing vibration to a minimum. An aluminum bowl is fitted with a hollow axle which fits over the motor shaft and is surrounded by a cylindrical copper shell which catches the discharged soluble material. The bottom of the shell is so inclined as to drain through a spout. The copper bowl is fitted with a two piece cover, the smaller of which is removed when adding additional solvent. Filter Paper is placed beneath the filter ring and both are inserted between the cover and edge of the aluminum bowl. The cover is held firmly in place by a filler screw which engages with the threaded hollow axle. Through this filler screw the solvent is added as needed. 1230. Dulin Rotarex, capacity 1000 grams, as described above, with direct drive vertical type motor for 110 volt direct or alternating current (excepting 25 cycles or less), enclosed in cast iron frame. Complete with rheostat, cord and plug for attaching to lamp socket, and directions for operating ... 185.00 1231. ditto; “bub capacity: 50 Brams cae cees ce eterna aun n teayeeiord anilec andy a mlevout as ay eWen ate co Maan ty 95.00 1232. ditto, 100 grams capacity, with hand drive instead of electric motor, for fielduse............ 70.00 1233. Plug with extra socket for operating Dulin Rotarex in series with a 110 volt incandescent lamp on 220 VO MtACIRCUMU ee caterer err Gs tn GME Po Ra ciad th ide calhict sUtn ine tol NOD ee hat wincyn ct gate ends ae t On oe ee Rea 2.25 1234. Filter Rings only, for use with No. 1230 Dulin Rotarex, 1000 gram bowl. Per100............... 5.50 1235. ditto, but for use with No. 1231 Dulin Rotarex 50 gram bowl. Per 100..................... 2.25 16 A R T AH U R FA. T H O M A _S Co 10> 3M. Ps A NOY a Avo 1290 1276 APPARATUS FOR TESTING CRUDE TARS, DISTILLED TARS AND PITCHES, HEAVY AND MIDDLE OILS, BENZOLS AND LIGHT OILS, as adopted by the Barrett Company, New York. See Journal of Industrial and Engineering Chemistry for September, October, November and December, 1918. The items listed below are only the special pieces of apparatus necessary for these tests. The regular apparatus such as Tripods, Supports, Porcelain, Silica and Platinum Crucibles, Distillation Flasks, Viscosimeters and Refractometers are to be found under their respective headings throughout the catalog. Complete lists of both the special and regular stock apparatus required for the various tests will be sent upon request. Several of these special items are also used in the Standard Methods for Distillation of Bituminous Materials Suitable for Road Treatment, and Sampling and Analysis of Creosote Oils, as specified by The American Society for Testing Materials, Reference D-20-18 and D-38-18. These items are designated by reference number after the listing of the item. 1256. Copper Still, large size, inside dimensions 73 x 5 inches... 0.0.00... 000000000 eee 22.40 1257 “Ring Burner;only; for abOverStille v2.2 ccene eck toe he kad ceded pchonencey tate ec tan eee ea ele pie at nak eu enen laehe 3.20 1260. Copper oo inside dimensions 6 x 33 inches, a3 used in Tests B-2, B-3, C-2 and H-2; also A. S. oa 1264. Ring Burner, brass, to fit Still No. 1260, as used in Tests B-2, B-3, C-2 and H-2; also A. S. T. M. DEB OU Biteics orceiin iced eras Soe il ta Ue woteet, Tree Ani ey wretch Mn uch oth ally ata ein St cr oT neath Rates neal wR 2.40 1268. Connecting Tube, of glass, as used in Tests B-2, B-3, C-2 and H-2; also A. S. T. M. D-38-18........ 35 10% discount in carton containing 12. 20% discount in carton containing 144. 1272. Condenser Trough, of copper, on supports, with wooden base, as used in Tests B-2, B-3, C-2, H-2, H-11, H-12, H-16, E-4, E-5, F-5, F-6, F-7, F-8 and F-10; also A. S. T. M. D-38-18............ 12.00 1276. Condenser Tube, of glass, to fit Condenser Trough No. 1272, as used in Tests B-2, B-3, C-2, H-2, H-11, H-12, H-13, H-16, E-4, E-5, F-5, F-6, F-7, F-8 and F-10; also A. S. T. M. D-38-18......... .20 10% discount in carton containing 12. 20% discount in carton containing 144. 1280. Separatory Funnel, with stopcock, capacity 120 ml, as used in Tests B-2, B-3, C-2, H-2 and H-12; also ASSN NER CB Oa Orr Onsite stennace crcettecat hare ese Octo erin fh esse oscar seattle Vent a caahn s Se APE aN 4.00 1284. Hydrometers, Specific Gravity, for liquids heavier than water, approximate length 9 inches. As used in Tests B-4 and H-3; also A. S. T. M. D-38-18. Sal Gas caret etre Beano ie St ad ct tu pained ain Aan ore Ne ne LIN 1.000-1.080 1.070-1.150 Graduated! toc che see id eee ee ners aro EE Pee bata ok Sans aca -001 .001 AC Dae een esa te vee eaten gee RBs BRM SL era So) Qi cere tice Wan eee men ee 2.80 2.80 1286. Hydrometers, Specific Gravity, for liquids heavier than water, approximate length 9 inches. As used in Test B-4. IS ead eps tlets ei cect cheese iso tesco a POPE ates OP ne Sonera ata eee eek oy ORO Sate 1.150-1.230 1.230-1.280 Grad Ate CO jst eee es ee A is aaa nice eRe he aie akon eo .001 .001 CHA in bis eter ah a nay REP EN PRN RH EON SS 2.80 2.80 Note—Cylinder No. 4390, size 250 x 40 mm. is suitable for use with above Hydrometers. 1290. Specific Gravity Bottle, Barrett Modification of the Hubbard form, 50 ml capacity, as used in Tests B-5, G28 and DaBigcr ta. cern o maces & ecaseee uaaal nisin ated eee mac nium rages Tie torn attee aah See eerie Anns 1.45 10% discount in carton containing 12. 1292. Platinum Pan for taking Specific Gravity, as used in Tests B-6, C-4, D-2 and H-8. At market price of platinum. 17 1294. 1295. 1296. 1297. 3876. 1300. 1301. 1304. 1306. 1308. 1310. 1312. 1314. 1316. 1318. 1330. 1332. 1333. 1334. 1325 1314 1326 Extraction Apparatus, Barrett Modification, complete with flask, cover, condenser and support of German silver wire, as used in Tests B-7, C-5, D-5 and H-5; also A. S. T. M. D-38-18............. 3.00 Glass Flask only, for above Extraction Apparatus..........0.0.0.0 0000. as 35 10% discount in carton containing 12. Wire Basket, only, of German silver wire, for above Extraction Apparatus..................... -50 Cover, with block tin condenser coil, only, for above Extraction Apparatus...................... 2.25 Filter Cap, Alundum, of RA-84 Mixture, 11 inch diameter by % inch high, as used in Tests B-7, C- e D=5 and H=53alsovA. Gis: Mes DEB 8208. 3 cic eco d Bae ghee nies aN ee Runcn niey GEA G es honed wh Schutte Penetrometer, with one plug. As used in Test C-7...............0.0.0 000s 3.15 Plugs, only, for Schutte Penetrometer. Each.. ; CAR aust A he SP i one RIS taal ies het ee ag es Pal? .65 Thermometer, Distillation, engraved on stem, 385 mm long, range 0 to 400° C, in 1° divisions. Corrected for total immersion. As used in Tests C-9, H-6, H-11, H-12, H-13, H-16, E-5, F-5, F-6, F-7 and F-8; and A. S. T. M. tests D-20-18, D-28-17 and D-38-18......................0..00.5. 10.00 Condensing Tube, as used in Test C-9, and A. S. T. M. D-20-18.........000.0.0.0....0.0..0.... -60 Condenser Cylinder, or Jacket, of glass, with two hole rubber stopper to fit condenser and inlet tube. AS ised.ine best ©-9: and Anco eos (MED E2 021.8 ong 8 cairns te trace ohne ie Goer eces aoa aaetyanre At dew do 1.00 Metal Shield for Burner, 200 mm long by 90 mm inside diameter, with small hole for observing flame; made of Russia iron. As used in Test C-9, and A. 8S. T. M. D-20-18.................0.... 1.00 Cylinder, Graduated, 25 ml in 1/10 ml divisions. As used in Test C-9, and A. 8. T. M. D-20-18... 1.00 Pitch Mould, consisting of iron clamps with brass block. As used in Tests D-4, D-6, D-7 and D-11. 5.60 Thermometer, Water Melting Point, engraved on stem, 375 mm long, range 0 to 80° C, in !° divisions. Corrected for total immersion. As used in Tests D-6, E-11 and H-18..................... 6.00 Thermometer, Air Melting Point, engraved on stem, 375 mm long, range +30 to 160° C, in }° divisions. Corrected for total immersion. As used in Test D-7.........0.0.00 0.00000 7.00 Burner Shield, of sheet iron, 8! inches high by 4 inches diameter. As used in Tests D-6, E-4, E-5, F-5, BiG R20) oO ede 2a Ria, 7s ae bees nls rare eta wats Sites Nace ashae elena. tthe acs 1.20 Air Melting Point Oven, of copper, with mica window, removable tray, etc., as used in Test D-7.. 9.60 Tripod, cast iron, 9 inches high, outside diameter 8 inches, suitable for use with above Oven....... .60 Burner Shield, of galvanized iron painted black, for use with Air Melting Point Oven............ 9.00 Copper Cup, 50 ml capacity, 1} inches diameter by 1{ inches high, as used in Test D-7........... 3.20 Funnel, 40 mm diameter at top, stem to fit Babcock Milk Bottle, as used in Test E-8............. 35 Hempel Distilling Tube, as used in Test F-8..... 0. eee -40 10% discount in carton containing 12. % discount in carton containing 144. Asbestos Ring, 4 inches diameter, with 1 inch hole in center, as used in Test F-8.................. 10 Thermometer, Benzol and Toluol No. 1, engraved on stem, 600 mm long, range 0 to 200° C, in }° divisions. Corrected for total immersion. As used in Test F-10.............0. 200.000.000.000 ceca 13.50 ditto, but No. 2, range 70 to 120° C, in ae divisions, 300 mm long. As used in Tests E-4 and F-10 7.00 ditto, but No. = range 110 to 160°C, in 1° divisions, 300 mm long. As used in Test F-10....... 7.00 18 7748. 1336. 1338. 1340. 1341. 1342. 1344. 1345. 1346. 1348. 1349. 5396. 1350. 1352. 1354. 1370. | a =a) 1 AMGF CO : cS a ‘\ ft CREOSOTE AH .c0 1342 1344 1349 Drying Oven, Single Wall, of copper throughout, covered with asbestos both inside and outside except bottom. Size 10 by 8 by 8 inches. As used in Test D-10.............................. 30.00 Evaporating Dish, of pure nickel, with flange and handle. As used in Test D-10................ 2.10 Melting Point Cup, for naphthalene determination...............0..00 00 ccc ccc cee ceeeeee 5.35 Slide Box, of copper, with six corrugations, as used in Test D-11...........000 00 cece eee eee eee 5.25 Retort, Glass, capacity 250 to 290 ml, as usedin Test H-6, and A. 8S. T. M. D-38-18............... 50 ditto; butOlyPyrexse lassi ie Late tyh cei cane cata tan eer Iote NA TAS tet crete U te Rn aes RCE, 1.90 10% discount in case containing 36. Condenser Tube, resistance glass, 375 mm long, as used in Test H-6............................ 45 10°% discount in carton containing 12. Asbestos Sheet, specially cut to fold into cover for Retort, as used in Test H-6................... -50 Coke Bulb, Pyrex Glass, as used in Test H-10, and A. S. T. M. D-38-18............0..0......... 18 Tar-Acid Separatory Funnel, Type 1, as used in Tests H-11, H-12, F-6 and F-7.................. 4.50 ditto, but Type 2, as used in Tests H-11, H-12, H-16, F-6 and F-7.......................... 5.40 Distilling Flask, Pyrex Glass, 200 ml capacity, as used in Tests H-11, H-12, H-16, B-4, E-5, F-5, F-6, F-7 and F-i0 See Arend or ore ene enc aN aa Mere ea en TAPED Anh ed RD Un Soman ee Dechy east we a een graben 55 10% discount in original case containing 54. Test Tube, 5 inches long by 1 inch inside diameter, medium weight, with slight lip, made of Pyrex glass. As usediin:Mests- Mal tands M18 os saii sc: sedans neaeitrale Mi cpehecnetee ms he 5 os Aust ba ok lec sins deol nsenic ean -40 Thermometer, Limpid Point, engraved on stem, 375 mm long, range—30 to 50° C, in }° divisions, corrected for total immersion. As-usedin: Test H=08 ici. dc-snive odcacieecon'acgtueiecd ovadabbaha ak Lab AChepck es 7.50 Hydrometers, Specific Gravity, for liquids lighter than water, approximate length 9 inches. As used in Test E-2. Galen eee cca glean Sada nays ccna nied eplantnemumeeaaes 0.790-0.870 0.860-0.940 0.930-1.010 Grad Uatedet factor teat a in coke ey Wied eee ate Uh ocean aoe -001 -001 001 ACH Se ee aaa ONE sa wee Sa uae Chin eA 1.50 1.50 1.50 Ring and Ball Melting Point Apparatus, in accordance with A. S. T. M. specifications for standard method of determining the softening point of bituminous materials other than tar products. Consists of a brass ring suspended in a glass beaker. Complete with steel balls..................0.... 16.35 19 A R T H U R Ee. T H O M A _§ Cc OQ mM —P. A N Y¥ 1390. Autoclave, for operating at pressures up to 1000 lbs. per square inch, consisting of a cast-iron retort of one pint capacity, 2 inches inside diameter by 5 inches inside height. The cover is provided with a thermometer well 3 inch (p. t.) thread, and an opening for attachment of safety valve or pressure gauge with 4 inch (p. t.) thread. Heavy lugs are cast as part of the retort, which serve as supports. Without burner, safety valve, pressure gauge, thermometer or stand.......... pe cde Mean 40.00 1391. ditto, with cast-iron support with removable legs, pressure gauge and burner, as shown in illustra- TPO Ne. eh ontsirat een, toast nA tan i Sach ye eared Lh eth Rae Ua Uae HORS ant (oye ek an ROE ee EUN EE alg 67.90 1394. Autoclave, or Digester, inside dimensions 100 x 200 mm, for 25 atmospheres pressure, capacity 13 liters. The retort is of hammered copper with lid of phosphor bronze. The pressure given is the steam test pressure, the working pressure being approximately 20% less. The working pressure is indi- cated on the manometer by means of a red mark. The pressure gauge is fitted with a control device whereby the gas is automatically shut off when any desired predetermined pressure is reached in the retort. This arrangement is not shown in the illustration. With safety valve, steam outlet cock, pressure gauge and thermometer well, and necessary wrenches but without DUTT Chis cco otal seein have BASS hee ted VaR et SCH a hos oA Oe aa tOR A es nts Tb He ESE ....... 100.00 1395. ditto, but with inside dimensions 125 x 250 mm, for 60 atmospheres pressure, capacity 3 liters... 165.00 1398. Autoclave, for operating at pressures up to 200 lbs. per square inch. With retort 83 inches deep by 5 inches diameter, with a working capacity of 1500 ml. Made of a solid grey iron casting machined smooth inside for convenient cleaning and for quantitative recovery. Stirring device with driving pulley requires 1/20 h.p. Provided with pressure gauge reading to 200 lbs., petcock, safety valve and a closed thermometer tubulation reaching to bottom of retort. Specially adapted for fusions with caustic soda, sulphonations, or nitrations, with or without pressure. This autoclave has been used for fusions of beta-naphthol over a direct flame without the observance of any carbonized material, due to the perfect agitation during the process; also for the fusion of amidonaphthol disulphonic acid, and alpha naphthylamine trisulphonic acid, and for amidation. Recommended as a laboratory size reproduction of the larger installations for commercial manufacturing. With special gas burner, but without thermometer........... ae cette el teeny mi etd ed man 275.00 9527. Thermometer, for use with above autoclave, graduated to 360° C, in 1° divisions, and to 600° Fin 2° AVIV AST ONS Ascetic steph clea a cesHl a Aleve cl ee reed estes ollcohh Arts bonne Aer ReS awh MNS oee Arar Rit OU AR we UUs 3.00 Autoclaves, or Steam Pressure Sterilizers, see Bacteriological Apparatus, pages 37 and 38. Our prices are subject to daily control and on all trade-marked or branded items they are identical with those established by the manufacturer. On all other items they are in accord with market conditions, being computed upon our net costs by means of definitely established formulae. Our prices are always identical on open orders and competitive proposals. Where time permits and exact advance information as to expenditure is required, we submit on request an itemized Statement of Current Prices for the items selected. 20 A R T H U_ R Eli T H OF M AS Cc Oo M P A N YF BACTERIOLOGICAL, SEROLOGICAL AND HISTOLOGICAL APPARATUS. INCUBATORS. AMERICAN STANDARD INCUBATORS are made of heavy polished copper, covered with a waterproof, non-conducting cork linoleum. They are of triple wall construction which provides spaces for the circulation of both hot air and warm water. The outer walls are thoroughly reinforced to prevent bulging, due to lateral pressure of the water, a defect very common in low priced utensils. The bottoms are conical in construction to heat evenly the water compartments on all sides by the circulation of hot air. The products of combustion and the hot air pass out by a ventilator on top of the incubator. A glass water gauge is supplied with stopcock which shuts off the water from the gauge in case the tube is broken. A metallic tube through the air jacket connects the thermo- regulator with the burner, and all burners furnished with incubators connect with this pipe by means of flexible metallic tubing instead of rubber tubing as previously used. In the gas heating equipment furnished with these oe we use only the Koch Safety Burner which, with the metallic connection, greatly minimizes danger rom fire. : Incubators are all furnished with a closed-in sheet-iron base with perforations for ventilation and mica wandow for observing the flame. They are also furnished with inside doors of plate glass, and thoroughly insulated outer doors. While the heating equipment regularly furnished with American Standard Incubators is intended for operation at about 374° C, temperatures of from 55° to 70° C are obtainable, so that incubators can be used for agglutinations, inactivations, paraffine embedding, and other work. This line of incubators has been continuously made for over 25 years in one of the first factories in the U.S. to take up the manufacture of bacteriological apparatus of sheet metal, and they are superior in workmanship, appearance and durability to any similar apparatus of European or American manufacture. Whether heated by gas or electricity, the jacket of warm water and warm air, surrounding the incubating chamber serves as the heating medium, thereby insuring uniform distribution of temperature throughout the chamber to + 3° C. under proper working conditions. Gas heating equipment supplied with American Standard Incubators consists of the following: 9580. Thermometer, Incubator, 0° to 50° C, with a red line at 371° 9640. Thermo-regulator, Roux Bimetallic, 12 inches long. 2690. Metallic Tubing, 30 inches long. 2686. Burner, Koch Safety, 6 x ;y inch, for No. 1401 Incubator. 2687. ne ee re 10 inch, for Nos. 1405 and 1411 Incubators. 2689. a “ “two burners, for Nos. 1415, 1421 and 1425 Incubators. The electric heating equipment supplied with American Standard Incubators consists of suitable heating units attached to the bottom of the incubators, which serve to heat the water; a solenoid, and a new type spiral form bimetallic regulator of great sensitivity. This regulator operates satisfactorily on 110 or 220 volt lines, either direct or alternating current, up to 500 watts. The incubators are supplied with cord and plug for lamp socket. These electrical components are not supplied separately, but any of our American Standard Incubators equipped for gas heating can be electrified by the attachment of this equipment, if sent to us for this purpose. Because of the low wattage required, electric incubators are usually used on incandescent lighting circuits, which are mostly 110 volts, and therefore, incubators are only carried in stock by us with heaters wound for 110 volts. Any of the incubators can be supplied with heaters for 220 volts on special order. Full instructions for operation sent with each utensil. 1400 AMERICAN STANDARD INCUBATORS, Hospital Type. These two sizes are supplied on low sheet-iron base 11 inches high and are intended for use on the laboratory table. They are of sufficient capacity to meet the requirements of cultural work in hospital laboratories, and are, in addition, of convenient size for other work in larger laboratories such as agglutinations, inactivations, paraffine embedding, etc. The dimensions given are inside. Height Width Depth Equipment Doors Shelves Price 1400. Incubator, American Standard, as described above 19 x 12 x 10 inches None 1 2 108.00 1401. “ee 6c “ce “e “ee “ce oe “e “ce oe z Gas 1 2 136.35 1402. a os ig ce e Me QO Rane, hi Electric 110 v. 1 2 175.50 1404. gS 3 ee ee es “20 x 18 x 10 . None 1 2 128.25 1405. “cc “ec oe oc “ce ae “e oe oe ‘“ Gas i 2 158.25 1406. os en es as o “ een ms Electric 110 v. 1 2 195.75 Ay Re oT oe) UR H. 1410 1414 AMERICAN STANDARD INCUBATORS, College Type. These two sizes are supplied on high angle iron bases 30 inches and 24 inches high, respectively, with enclosed compartment for burner. They are of sufficient capacity to meet the cultural requirements of many educational laboratories, medium size hospital laboratories, and for general work in larger laboratories. The dimensions given are inside. Height Width Depth Equipment Doors Shelves Price 1410. Incubator, American Standard, as described above 18 x 18 x 12 inches None 1 2 155.25 1411. ce “ce “cc “ce cc“ “ “ “ce “cc “ac Gas 1 2, 185.25 1412. me i“, ws se a . cy sy ie re Electric 110 v. 1 2 222.75 1414, ae ee Mi i eo DB AR 1A FE None 1 2 202.50 1415. “cc oc “ee oe “ce “ce cc“ “ce cc “cc Gas 1 2 250.85 1416. ns ie iG - ce eee Electric 110 v. 1 2 270.00 AMERICAN STANDARD INCUBATORS, Board of Health Type (illustrated on following page). These two sizes are provided with double doors, and are supplied on high angle iron base 33 inches high, with enclosed compartment for burner. They are of sufficient capacity to meet the ordinary cultural requirements of large hospital and Board of Health laboratories. The larger of these two sizes represents the maximum dimensions to which it has been found practicable to build sheet metal incubators of the triple wall construction, and where a larger capacity is required we recommend duplication of the incubator, or the building of incubating rooms for which we list equipment on pages 31 and 32. The dimensions given are inside. Height Width Depth Equipment Doors Shelves Price 1420. Incubator, American Standard, as described above 18 x 30 x 14 inches None 2 4 222.75 1421. “e “ce “e oe cc ce ce oe “ce ce Gas 2 4 271.00 1422. es iy i ee es oe ts ns os Electric 110 v. 2 4 290.25 1424. a es se oe os “25 x30x18 “ None 2 4 263.25 1425. ce “ce ce “ce “ce “ce “ee “ “cc “ce Gas 2 4 311.50 1426. oe “ce ce oe oe oe “ce “cc oe ce Electric 110 Vv. 2 4 337.50 1430. Shelves, only, for American Standard Incubators. For size....... 19x12x10 20x18x10 18x18x12 28x18x14 18x30x14 25x30x18 Bachs.3 hea 4.40 4.80 4.80 6.40 6.40 6.80 22 1420 1424 American Standard Incubator American Standard Incubator (Described and listed on preceding page) HEARSON INCUBATORS HEARSON INCUBATORS. The gas and oil heated incubators consist of a water-jacketed chamber made of stout copper surrounded by insulating material and the whole encased in wood. They are provided with an inner door of glass and an outer one of paneled wood. The distinctive feature is the temperature control by means of a metallic, hermetically sealed capsule which contains a few drops of liquid having a boiling point at or near the temperature which it is desired to main- tain in the heating chamber. The regulation is established by the expansion of the capsule owing to the boiling of the contents which provides the motive force for operating the control lever. This expansion takes place only at the predetermined temperature. The lever will only be acted upon when the critical temperature is reached, no sensible effect being produced at even one degree below that at which the capsule is desired to act. A sliding weight compensates for slight barometric and room temperature variations, and, in addition, controls within certain limits the boiling point of the capsule. The total temperature range possible by means of these capsules is from 16° C to 175° C. In the anhydric electric incubators, the expansion of the capsule, controlled by the lever with compensating weight, as in other forms, simply makes and breaks the electric circuit. This device works equally well on either direct or alternating current. The heating effect is produced by an even distribution of one or more electric resistance wires, covering every part of the apparatus ordinarily occupied by the water jacket. Suitable terminals controlling each unit permit of the resistance being utilized in various combinations in order to provide for high or low temperatures, or to enable the operator to adapt the apparatus, within certain limits, to certain voltages. This method of heating, used, so far as we are aware, only in the Hearson Anhydric Electric Incubators, provides a much quicker attainment of the desired temperature, and insures uniform distribution of temperature throughout the incubating chamber within -+-3° C, attainable with no other form of anhydric electric incubator. We have sold Hearson Incubators for the past 10 years with a remarkable degree of satisfaction to the users. While the finish and appearance does not equal that of some other makes, the utensils are of a rugged and durable construction, with the result that we have never had a significant complaint as to any defect of construction or operation of any Hearson utensil we have ever sold. The temperature control by means of the Hearson Expan- sion Capsule is the simplest and least likely to get out of order of any device available, and a temperature control within +3° C throughout the incubating chamber is possible with any of these incubators. Hearson Incubators are stocked by us in the five sizes listed on following page, these having been found to meet most requirements of American laboratories. Several other sizes can be imported on special order. Because of the low wattage required, electric incubators are usually used on incandescent lighting circuits, which are mostly 110 volts, and, therefore, incubators are carried in stock by us with heaters wound for 110 volts. Any of the incubators can be supplied with heaters for 220 volts on special order _ : ; Full instructions for operation sent with each utensil. (For listing and illustrations, see following page.) 23 4 ai 1440 1444 1448 HEARSON INCUBATORS, as described on preceding page, are furnished with Expansion Capsule ‘“C”’ for operation at 374° C, unless otherwise specified. The gas heated incubators are furnished complete with burner for ordinary illuminating gas, and thermometer; oil heated with oil lamp and thermometer; and the electrically heated with cord and plug for lamp socket, and thermometer. Width Depth Height Equipment Shelves Pric 1440. Incubator, Hearson, as described above, 9x 9x 12 inches Gas 1 ; 85.05 1441. “ “ ce “ “ Py ae ee “ Oil 1 85.00 1442. es ee me = es eo - ea Electric 110 v. 1 95.20 1444, a ns SS es as 12x12x14 “ Gas 1 106.30 1445. oe “cc “cc oe“ “e oe oe 6e “ce Oil 1 106.30 1446. ee ss es i e eee ue tere et Electric 110 v. 1 123.00 1448. ~ sg “s a ns 15x 15x18 ie Gas 2 155.00 1449. “ “ ve “ “ eR ee RE “ Oil 9 155.00 2 159.50 1450. “ “ “ “ “ “ “ “ “ Electric 110 v. ‘= | | 3 a i 3 { i I Wal nN Hi Ny 4 | eT i : : 1452 Width Depth Height Equipment Shelves Price 1452. Incubator, Hearson, as described above, 20 x 20 x 24 inches Gas 2 220.50 1453. “ a eas a Electric 110 v. 2 230.75 1454. . Be = o i 18x14x35 “ Gas 3 238.00 1455. me i = ee ra ane Electric 110 v. 3 261.50 24 A R T H UR H. T H O M A _S§ C O M P AN Y Capsules, Hearson Patent Expansion, as used in the various Hearson utensils. The capsules are 2 inches Square and are stamped with the boiling point of the contents in degrees Centigrade in a room temperature of 60° C, and for a barometric pressure of 30 inches. Each capsule has a maximum range of about 10° C higher than the boiling point with which it is marked. This range is accomplished by retarding the boiling point by means of the pressure exerted by the sliding compensating weight on the lever arm of the regulator. The capsules cannot, therefore, be used for temperatures appreciably lower than that for which they are stamped unless this is possible because of use at higher altitudes. Boiling Point Maximum Range For 1460. Capsule “A” 16°C 10°C Low Temperature Incubators. Gelatine Cultures, ete. Fa ¥ “B” 25°C ss Seed Germination, etc. Os 35° C es Ordinary bacteriological work, Agglutinations, ete. ie De 45°C a Paraffine Embedding, Agglutinations, etc. i * “E”’ 55° C Paraffine Embedding, Inactivations, etc. o a one 65° C e Paraffine Embedding ai a “Gq”? 75° C es Inspissating “ ‘ “A 85° C ‘ BROT Shani yee a A Si tid on ot Gets oer te eA ey «nen 2.40 1461. Special Burner for Gasoline Gas, interchangeable with regular gas burner. For use only on Hearson Incubators. BURCH a copes ae ee eed ae een ee Pe On Aaa ne ya Ae .20 1462. Shelves, only, for Hearson Incubators. For size........... 9x9x12 12x12x 14 15x 15x 18 20 x 20 x 24 18 x 24 x 35 Bach: Bounce erate 1.50 1.75 2.15 2.40 2.70 My hi | H i I 1471 1473 C. S. & E. ANHYDRIC ELECTRIC INCUBATORS t } ELECTRIC INCUBATORS. These are made of wood, lined with tar paper, animal ee eee ee ou finish is in hand rubbed quartered oak, ae the nied sy Sonat uation ly prevents warping, checking or cracking. The tar paper, animal hair and transite insu } pe geo e Soe and an absolute protection against fire on the inside. The ventilation arrangement provides pe sontindans circulation of air and reasonably uniform heat distribution throughout the compartment. The fe g units are in the bottom of the incubator on a manele pike. and ote pasly tenliond, eulident iene ae las i i t a temperature of 373° C, and w r' ‘ supplied’ ce ee te. additional units can readily be added to the heating plate eee e higher temperatures. (Continued on following page.) 25 Po -A NY 1475 Cc. S. & E. ANHYDRIC ELECTRIC INCUBATORS (Continued) The thermo-regulator is built upon the principle of unequal expansion between a bronze and hard rubber disc. It has been found after several years’ use to be sensitive and reliable when carefully used. While the range of these regulators is from about 30° C to 60° C, it is not recommended that they be used alternately over this entire range, as when a regulator is once adjusted for the higher temperatures the diaphragm conforms with the increased expansion at such temperatures, and it does not readjust satisfactorily for the lower temperatures. The C.S. & E. regulators are furnished with a condenser which kills the electric spark when the contact points are separated, providing the electric current passing through same does not exceed 3 amperes. Where greater current is required, as in the control of temperature of larger incubators or incubating rooms, an electric solenoid must be used asrelay. This is not required with any of the regular size C. S. & E. incubators listed below. In common with other anhydric electric incubators with heating units in the bottom of the incubating chamber, some variation in the uniform distribution of temperature throughout the incubator compartment must be expected. Because of the low wattage required, electric incubators are usually used on incandescent lighting circuits, which are mostly 110 volts, and, therefore, incubators are carried in stock by us with heaters wound for 110 volts. Any of the incubators can be supplied with heaters for 220 volts on special order; but 110 volt incubators can be used on 220 volts by grouping the heating units so two units are always connected in series, thereby making it possible to use the same heating units for either 110 or 220 volts, with only a slight change in electric wiring. C. 8. & E. Anhydric Electric Incubators, as above described, are suitable for use on the laboratory table, or on the angle iron stand, as preferred. These stands are 33 inches high, and are recommended where sufficient laboratory table space is not available. With each incubator is included cord and plug for electric light socket, thermometer, and complete directions for operation. Height Width Depth Stand Shelves Doors Price 1470. Incubator, C. S. & E. No. 2, as described above, 110 v. 26x 18x18 inches Without 1 1 100.00 1471. “ “ 1 gg) be ‘ “ fee ote ee ic With 1 1 112/50 ie % 2s «Bye 4 = “ 30x20x18 “ Without 3 1 125.00 1473. € ie “4p « “ f METEOR wei With 3 1 137.50 cae a a wage 4 : “30x 36x18 “ Without 6 2 225.00 1475. as fe * 33, °° a : o ne os With 6 2 240.00 1478. Stands, only, 33 inches high, for preceding C. 8. & E. Anhydric Electric Incubators. WOr-Size WNChes 5:23 6.4 ee ees Be OM a 26x 18x18 30 x 20 x 18 30 x 36 x 18 SCR he Sys Gin ae un ge porn a amas Be oe i ae 12.50 12.50 15.00 1479. Shelves, only, for preceding C. S. & E. Anhydric Electric Incubators. Hor: size: In Chess neon bine aetna nk a eons 26x 18x18 30 x 20 x 18 30 x 86x 18 ACH ee eee ee a Td eat OL es 1.50 2.00 3.00 A R T H U_ R H. T H O M A _ §S C O M P A N_ Y Heating Plates, C. S. & E. No. 47, of transite, with connections and No. 9676 Heating Units, but without thermo-regulator. The plates are all 1} inches high. Size 15 by 15 inches is intended for use in Incubators Nos. 1470, 1471, 1478, 1474 and 1475, two plates being required for Nos. 1474 and 1475. Size 9% by 92 inches is for Incubator No. 1515. The heating plates for temperatures 56 to 60° C, are identical with those for 373° C, except that they have more units. These plates for use in utensils other than the regular C. S. & E. line are supplied with thermo-regulator attached, and are listed under No. 9664. 9672. Heating Plate, C. S. & E., 15 x 15 inches, for 373° C, with 4 Heating Units................... 12.00 9673. c a os ‘i oe a “ 56-60°C, “ 6 a Py ee ea nen hips Nae nae 14.00 9674. ci c m4 93x91 “ “ 374° C, sos SD, ie CPi Ser cia PeReN Aer oieee ee neta hte 7.50 9675. es “ . a air! “ §6-60° C, “ 4 - Oe oie ie nities com tno i 9.50 9676. Heating Unit, C.S. & E. No. 44, as supplied with No. 9672 Heating Plates. A lava composition rod with brass terminals, size 3 x 3 x 12 inches. Maximum current consumption } ampere on 110 volts. 1.00 9662. Thermo-Regulator, C. S. & E. No. 5 Patent Electric, with a range of from 30° to 60° C. With condenser which protects the platinum contacts from arcing, providing the current does not exceed 3 amperes. Space occupied approximately 7 by 53 by 23 inches high....................0 0.00000 13.00 T || Hi t alli y i wt ( l oo i 1494 FREAS ELECTRIC INCUBATORS CTRIC INCUBATORS. The double walls and doors are of heavy asbestos transite, insulated witha Serta material of high efficiency, thus insuring against loss of heat and at the same time keeping the laboratory cool and comfortable. The incubators have an inner glass door for observation of cultures, without the danger of lowering the temperature of the chamber. Frames, door frames, shelf racks and bushings are of cast aluminum of ample strength to withstand the hardest usage. The heating element consists of an asbestos transite late, wound with a durable resistance wire. Heat regulation is by means of the Freas Patent Thermo-regulator, Fad is of extremely sensitive and reliant construction. The regulator is the most important feature in all Freas apparatus. The regulation is sharp and accurate and remains so indefinitely, and is constant to within a fraction te de ee. The regulator can be set in advance, by means of a milled head screw, to the approximate desired Fceaper ature: The final adjustment is made by reference to the thermometer. A lamp is provided for this purpose and for inspection of the interior of the incubator, and may be used as a pilot if desired. All switches and other 27 1496 FREAS ELECTRIC INCUBATORS (Continued) controls are operated from the outside of the incubator and no vapors from evaporating residues can reach the contact points. Stands are of heavy cast iron, finished with washable sanitary enamel. Inside finish of the incubator is a washable metallic paint of great durability. Outside finish is pleasing and durable. In common with other electric incubators with heating units in the bottom of the incubating chamber, some variation in the uniform distribution of temperature throughout the incubator compartment must be expected. Because of the low wattage required, electric incubators are usually used on incandescent lighting circuits. These incubators have been approved by the National Board of Fire Underwriters. Freas Electric Incubators, as described above. The three sizes listed herewith have been found to meet most laboratory requirements. Two additional sizes can be supplied on special order. The high stands for incubators Nos. 28 and 40 are 35 inches high; and all incubators are supplied with cord and plug for lamp socket, and thermometer. Height Width Depth Stand Shelves Doors Price 1490. Incubator, Freas No. 26, 110 v. 12 x 12 x 12 inches Low 2 1 140.00 1491. “ce “ “ee “ce 220 Vv. ce “ “ce 6c ce 2 1 140.00 1492. ae ss “ 27,110 vw 16x16x14 “ se 2 1 220.00 1493. aS OS ON 1220 -Ve pa aceg ao % 2 1 220.00 1494. A “28, 110 v. nO mrs nae High 2 1 235.00 1495. 4“ “cc “ce “ 220 Vv. cc “ce ce se “ce 2 1 235.00 1496. nf ns “40, 110 v. 223x32 x 18 sg 4 2 390.00 1497. “cc “ec ““ ce 220 Vv. “cc “ce “ce ee “ce 2 2 390.00 1499. Shelves, only, for Freas Electric Incubators. MOK incubator N Oise a cone. close Guetaho tan Wh Wa Soe Wala ear ee ds veto 26 27 28 40 AC Hee eter sete ea peerage ean ter van heen eed hrm ane 150 1.75 1.75 4.50 9582. Thermometer, Incubator, etched on stem; specially designed for use with Freas Electric Incubators. Range 0° to 70° C, in 1° divisions. Total length 22 inches, with zero point of scale 12 inches from bulb, so that entire scale remains visible at all times............000..0 0... c ccc cc cece ee 5.00 28 1510 MISCELLANEOUS INCUBATORS C. S. & E. Electric Office Incubators, of the same general construction as the C. S. & E. large laboratory incubators, but heated with carbon filament lamps, and with single door fitted with blue glass. These are very convenient for office incubations or laboratory work where only occasional cultures are to be grown. They are widely used in City Health Departments in the collecting stations for diphtheria throat swabs, etc., and are heated by an 8 c.p. incandescent carbon filament lamp for 110 volts, but can be used on a 220 volt line by substituting a 220 volt lamp. Complete with Thermometer 100° C. Regulation is by means of a C. S. & E. Regulator No. 9662, as used on the larger incubators. ; 1510. 1512. 1513. 1515. 1518. 1520. 1521. 1522. 1523. Incubator, Desk, C. S. & E. Electric No. 1, heated by one 8 ¢.p. carbon filament lamp, single door with blue glass. Inside dimensions 9 by 7 by 7 inches. Lamp furnished is for 110 volt circuit. With thermometer,,-cordand) DIG ic ooo ssc tein et ae nee Be espe ow Bate PSG wae eer ers aoe ebreis 35.00 Incubator, Office, C. S. & E. Electric No. 3, exactly same as Desk Incubator, but heated with two 8 c.p. lamps. Inside dimensions 12 by 9 by 9 inches. Lamps furnished are for 110 volt circuit. With thermometer cord arGupl.u pies oo skoecr 1 eeteesee sai Aes devs thatectrs iSacck Sees Sete sacar SIBoR RRS Bae Byers 40.00 Lamp, Carbon Filament, tubular form, 8 c.p., 110 volts, as used in above Incubators.............. 1.00 Incubator, Office, C. S. & E. Electric No. 11, identical in construction with the C. S. & E. laboratory incubators but of smaller size. With double doors, the inner of glass and the outer of wood. Heated with No. 9674 Heating Plate. Inside dimensions 15 by 12 by 103 inches. With thermometer, cord and plug 1518 1520 Incubator, Office, C. S. & E. Electric No. 62. This is of the same general construction as C. S. & E laboratory incubators, but is of a special shape providing large incubating space at a minimum price. A glass porthole is substituted for the interior glass door, and otherwise the construction is simplified. The incubator is heated by No. 9674 Heating Plate, and the temperature is controlled by an automatic electro-thermostat. Furnished with removable thermostat key to prevent tampering by outsiders. A pilot lamp indicates when current is On or Off. Inside dimensions 17 by 14 by 12 inches. With one shelf, thermometer, pilot lamp, cord and plug. For 110 volts......... 65.00 Incubator, Office, of copper throughout, with inside door of glass. Of double wall construction without cork linoleum insulation. Inside dimensions 10 by 12 by 10 inches. Very satisfactory for use as a paraffine embedding oven. With one shelf, water gauge, enclosed sheet-iron base, but without thermometer, thermo-regulator or burner..... eiite ata Austin ee sae ey itla tae eat yaaa: Gust meatal 51.25 ditto, but with equipment for gas heating consisting of Thermometer, Roux Thermo-regulator, {Odneh, and Burnerd-biinchy.¢ sie nian ty eee see oe coe SA 8 ER RUE Bgl lhe ecinas Maes eae 75.35 Incubator, Office, of same general construction as our American Standard Incubators, except that it has a double wall instead of triple, i.¢., without circulating water jacket. Of copper throughout with cork linoleum insulation and with inside door of glass, and two shelves. Inside dimensions 12 by 10 by 10 inches. On enclosed sheet-iron base 9 inches high. Without thermometer, thermo- regulator or burner..............-- erence a ee 67.50 ditto, but with equipment for gas heating, consisting of Thermometer, Roux Thermo-regulator, 10 inch, and Burner, 5 inch........ 003020 00s bby eee Seer ent ede sees kee eee ees 91.50 H. TT H O M A S CO: “M.-P A oN _¥ 1530 1532 1532 Knocked down ready for shipment Set up for operation FIELD INCUBATORS We offer two Incubators with oil heating device, constructed throughout of sheet copper and particularly designed for expeditionary use. The American Standard Incubator was for many years the standard equipment of the U. S. Army Field Laboratories, and has now been superseded by a larger incubator of different construc- tion, the U. S. Army Field Model, but because of the great satisfaction which has been found in the use of the older model, we retain it for use where its size meets the requirements. The present U.S. Army Field Model operates equa'ly well with oil, gas or electricity, and in expeditionary work it is recommended that at least one extra type of heater be included in the equipment. 1530. Incubator, American Standard, Field Model. A triple-wall construction of copper throughout covered with cork linoleum, identical in every way with our regular American Standard Incubators but arranged for oil heating. A Roux Thermo-regulator which directly operates the damper over the lamp regulates the current of hot air passing through the heating compartment. In this size incubator, the regulator will control the interior temperature within 4° without difficulty. Inside dimensions 12 x 9 x 9 inches, outside dimensions 17 x 14x 13 inches. The stand is 25 inches high and is packed separately from the incubator. The oil lamp can be replaced with a gas burner for equally satisfactory operation. Complete with thermometer, Roux Thermo-regulator and oil heating lamp asshown. On high hase...........0..00.0.00.0 0 cee cece teen eeee 111.25 1532. Incubator, U. S. Army Field Model. The incubating space is 16 by 16 by 16 inches, with two adjust- able shelves, capsule control, and stand of angle iron which telescopes down over the top of the incubator when packed for shipment. The incubating chamber is surrounded entirely by a copper water jacket, which in turn is surrounded by an outside insulating space filled with mineral wool and covered with asbestos board, the sheet metal parts being of copper through- out. With thermostatic control, weight compensating device, oil heating lamp, etc. Weight complete:for operations D121 bi. ay. ec an ea ois as eee ae donk boro tn) A ene stead aa ele 195.00 1533. ditto, with gas burner instead of oillamp..................... Ran oversee. .. 195.00 1534. se “electric heater for 110 volts, instead of oil lamp.... .. eae ee .... 205.00 1535. Oil Lamp, only, for above incubator.... ........... Neen Boeera ter | arpa enna mete Nyce 7.00 1536. Gas Burner, only, for above incubator. ......................... OVA CRN Ee aan cag? 7.00 1537. Electric Heater, only, for 110 volts, for above incubator.............. Pres e aids Sattgoc. 600 LOW TEMPERATURE INCUBATORS HEARSON MODEL “C” LOW TEMPERATURE INCUBATORS, specially designed for the incuba- tion of gelatine cultures at 20° C, or at any other predetermined temperature, using only the theoretical amount of ice requisite to obtain this result, even though the external air may be 30 or 40 degrees above the tempera- ture desired in the interior. While regularly supplied with a gas burner, the heating can be done with any kind of burner, the only requisite being connection with a constant water supply. The apparatus consists of a water-jacketed chamber identical in general construction to Hearson Incubators previously described, but in addition surmounted by a compartment containing ice. The regulation within the chamber is effected by a small stream of water which runs continuously in one of three directions, the particular one being automatically determined by operation of the capsule. , < The Hearson Model ‘‘C” Low Temperature Incubator is one of the most satisfactory bacteriological utensils we have ever sold and has been supplied by us during the past ten years to U. S. Government laboratories, leading Universities, State and City Boards of Health, where they are used with uniform satisfaction. 30 A HEARSON MODEL “C” LOW TEMPERATURE INCUBATORS (Continued) These Incubators are regularly furnished with Hearson Expansion Capsule “‘A”’ (see page 25) with a range from 16 to 26° C, and are complete for operation. The gas burner regularly supplied is for use with ordinary illumi- nating gas. Where gasoline or natural gas only are available, Burner Tip No. 1461 should be ordered in addition. Larger sizes are imported to order only. Inside Dimensions, Inches Heating Shelves Price 1540. Incubator, Low Temperature, Model “‘C” 12x 12x14 Gas -lt 220.00 1541. af a i Me uF eA pretig coe Oil il 220.00 1542. is _ eS - * 15x 15x18 Gas 2 277.25 1543. a ae - i, asc ee a Oil 2 277.25 22/8 Solero, 22°24 Heoding Stoves Fig. 2 (For text see following page) Fig. 1 For text see following page) 31 A R T H UR H. T H O M A S Cc O M P A N Y EQUIPMENT FOR HEATING AND REGULATION OF INCUBATING ROOMS Construction of Room. In the building of constant temperature or incubating rooms, the most important consideration is that of insulation. Walls made of alternate layers of 3 inch wood flooring and one thickness of 1 inch cork, with intervening layers of building paper, make a satisfactory construction. The number of layers used should depend on the size of the room. The layers should be firmly nailed together with corners overlapping. The doors should be constructed of the same material, and door casing covered with felt to make it tight and dust- proof. The ceiling, walls and door should be covered with a layer of } inch transite and painted to prevent re- tention of odors and absorption of moisture. Fig. 1 on preceding page shows a conveniently arranged incubating room fitted out with electric heat- ing and regulating equipment. Fig. 2 shows suitable wiring connections for this installation. We are prepared to quote prices on gor iete incubating room as shown in Fig. 1, knocked down and packed for shipment, but ii | i 1550. Gas Regulator, Hearson. With a well insulated room a uniform temperature can be maintained within 2° with the use of the gas valve regulator and a suitable gas stock. It is advisable to arrange venti- lation in both the lower and upper parts of the room for the purpose of temperature equalization and avoidance of smell from the products of combustion and gases of fermentation, etc. The regulator may be placed at any convenient position, usually near the door. Price is for gas valve Withscapsule Only. occe scar altensawd alah. va ancett sien Device cael rai Ban dN ate elec Sil Ohne en LAr 18.50 1552. Electric Heater and Regulator, C. S. & E. No. 73. This equipment is designed to maintain constant tem- perature of 373° C in a room 4 ft. x 6 ft., with a ceiling not over 7 ft. high, as shown in Fig. 1, page 31. For larger rooms it is simply necessary to increase the number of heating stoves, which should be placed about 3 ft. apart as the maximum distance for best results. This equipment con- sists of Thermostat, Actuating Stove, five Electric Heating Stoves, Solenoid, one ventilating fan with piping, necessary conduits, fuse box, snap switches, electric wires, etc., for completing the installation. For 110 volt a.c., 60 cycles. Capacity of Solenoid 6 amperes............. 290.00 1553. ditto, but for 110 volt d.c. Capacity of Solenoid 10 amperes....................... 0.000. 290.00 1554. Heater, Electric, C. S. & E. No. 24, as used in Heating and Regulating Equipment C. S. & E. No. 73. Size of base 143 x 5 inches, height over all 4 inches, with screw terminals for connections. Current consumption 2 ampere. For 110 volts.............00 0.00 eee 16.00 i w= oe i = Wales My f iM | ee Ce a ai | SOT i q iS ) i | =a i fi ‘ll : prane MN a 1554 1557 1555. Actuating Stove, C. S. & E. No. 25, as used in Heating and Regulating Equipment C. S. & E. No. 73. Size of base 9 x 33 inches, height over all 3 inches, with screw terminals for connections. Current consumption + ampere. For 110 volts............0 0... cence eee 16.00 1557. Electric Solenoid, C. S. & E. No. 18, as used in Heating and Regulating Equipment C. S. & E. No. 73. As the contact points on C. S. ’& E. electro-thermostats will carry with safety only 3 amperes, the electric solenoid is constructed for use where currents from 3 to 10 amperes are used for heating large incubators or incubating rooms. In special steel box, as required by the Board of Fire Underwriters. For d.c. up to 10 amperes.......... 00.0... eee 70.00 1558. ditto: butdtor aseUp tO Gam Peres: cice.t. sass c ase cmacte: eae satan aes wea stmane mains eae kala ete cteesss oot 75.00 COMPARTMENT INCUBATORS FOR STUDENTS’ USE These are available of both Hearson and Chicago Surgical & Electrical Co. make, with from 12 to 48 interior drawers or compartments. They are not carried in stock. Prices quoted on application. 32 1570. 1571. 1574. 1575. 1576. 1577. 1578. 1579. 1588. 1574 COAGULATORS (INSPISSATORS) Coagulator, or Inspissator, Hearson Electric, identical in general construction and operation with Hearson Electric Incubators. Stoutly constructed of wood with copper water bath and felt cover. In- side dimensions 23 x 11 x 3 inches deep, capacity 40 culture tubes held in four separate trays in a slanting position. Complete with one each No. 1460 Hearson Capsules ‘‘G’’ and ‘‘H’’ for opera- tion between 75° and 95° C, thermometer and cord and plug; for 110 volts.............. 92.25 Slanting Rack, of tin, as used in Hearson Coagulator. For 10 tubes...............0.0 0000200005 1.50 Coagulator, or Inspissator, C. S. & E. Electric, No. 80, of similar construction to other C. S. & E. Water Baths, 7. e., of copper with transite insulation. Inside dimensions 22 x 124 x 3} inches, total height including stand 12 inches. With two racks, each holding 18 tubes in slanting position. Total. capacity: 36: tubes: For 110: volts. ocnc 24 cent chine Bk Sisal hs A se OE 120.00 Slanting Rack, C. S. & E. No. 87, as used in C. S. & E. Coagulator. Of brass with pins for adjusting the incline: of the rack, Capacity 18 ‘tubes... ccc os eas ce eae cae cee ce etna eee ee 10.00 1576 1578 Coagulator or Inspissator, for gas heating. The two front legs are slotted so that the apparatus may be tilted for securing the necessary slant to the test tubes. Of same construction as American Standard Incubators, 7. e., polished copper tinned inside and covered on the outside with a waterproof non-conducting material. Inside dimensions 12x 10x 2) inches. Without thermom- éter: thermo-regulator’ or. burnefss . eau cod ed er Shes eta aes Mew eed wen eae se 40.00 ditto, but with Thermometer 100° C, Reichert Thermo-regulator and Koch Burner, 6 inch size.... 53.25 Coagulator or Inspissator, exactly similar to preceding, but with inside dimensions 16 x 14 x 2} inches. Without thermometer, thermo-regulator or burner............0... 0000 cece ene 48.00 ditto, but with Thermometer, 100° C, Reichert Thermo-regulator and Koch Burner, 6 inchsize.... 61.25 Agar Slanting Device, neatly constructed of hardwood, with a capacity of 20 standard size culture tubes on each shelf. By movement of a wedge under the bottom shelf, slants of any desired angle are obtainable. Total height 153 inches, depth 53 inches, width 13 inches. With six shelves. As suggested by Dr. Oskar Klotz, Dept. of Bacteriology, University of Pittsburgh........... 12.00 33 1590 1592 1593 HOT AIR STERILIZERS 1590. Hot Air Sterilizer, double wall, of sheet iron, with one shelf, removable cast iron legs, and with hangers and a fork for the burner so sterilizer can be hung on the wall when legs are removed. Inside dimensions 12 inches high by 9 inches wide by 9 inches deep. With Thermometer, 200° C, and Burm Org A Ch sc sata es sats 5 a ako sed oe alta Se Saeia eg wASe eee doa es ante ianin ote eens be lath inal wana 15.75 1592. Hot Air Sterilizer, double wall, of sheet iron, with two shelves, enclosed base, asbestos mat, Thermometer, 200° C, and Burner } inch. Inside dimensions 10 inches high by 12 inches wide by 10 inches GEG pig gees peti co nese ee ae ey Se Gee lcs oat oe crn Gay hs od sR SORE uate Pence Gect eae 27.35 1593. ditto, but with outer wall covered with asbestos, affording greater insulation and economy of heat EMS ret ee tL GH Sra Nee ERA A: Patna cecea Ciao one pe Legic: Boole 1598 HOT AIR STERILIZERS, Model of the U. S. Army Medical Department, for both gas and oil heating; double wall, of sheet iron covered with asbestos on the outside, with built-in gas burner and adjustable control valve permitting the use of either ordinary coal gas or gasoline gas. Provided with opening in the bottom with conical baffle plate for use with oil burner when no gas is available. An enclosed sheet iron base is provided to protect the oil burner from drafts. A ventilating chimney with adjustable damper is provided at top as are also adjust- able sliding ventilators at each end for regulation of inflow of cold air. Guaranteed to maintain a temperature of 175° C to 185° C, throughout the sterilizing chamber when heated with either coal gas, gasoline gas, or kero- sene. These sterilizers were designed by us especially to meet the requirements of the U.S. Army Medical Depart- ment during the war. Each sterilizer is provided with a No. 9525 Thermometer 200° C, and a gas burner. The sterilizers listed with gas and oil heating equipment are identical with those for gas heating, but have a Khotal Kerosene Burner added. The large size sterilizer is supplied with two Khotal Kerosene Burners, in addition to the gas burners. Height Width Depth Equipment Shelves’ Price 1596. Hot Air Sterilizer, U. S. Army, as described above, 12 x 18x 9 inches Gas 2 46.00 1597. pete — o BN a i De cre en nan Gas and oil 2 53.35 1598. ee Pr a Rie | ee ‘6 “ 18x24x14 “ as 5 62.00 1599. “a 6“ “ ‘ 6c ““c 6“ “6 “cc 6 6c 66 Gas and oil 2 76.75 34 A R T H U_R H. T H O M A S§ C O M P A N _ Y 1607 1614 _ HOT AIR STERILIZERS, AMERICAN STANDARD, Triple Wall, with the regenerative heating arrange- ment in the so-called “‘Lautenschlaeger” form of sterilizers. Of sheet iron with outside covered with asbestos. The three-wall arrangement provides two air spaces, and as the burners are built in the outside air space the circulating air current passes through and around the oven, affording a uniformity of temperature throughout the interior compartment, attainable by no other method of heating, and obviating the possibility of any burning of an article lying near the wall of the sterilizer. . These sterilizers are now provided with adjustable valve gas burner, so that they can be used with equal efficiency on gasoline, natural, or ordinary illuminating gas. Because of the triple-wall construction, which de- pends for its effectiveness on the built-in gas burners, we do not recommend these sterilizers for oil heating. They are satisfactorily arranged for electric heating by means of heavy duty resistance heaters placed under the bottom. The considerable current consumption required is occasioned largely by the surrounding air jacket, which must become thoroughly heated before the interior chamber comes to a sterilizing temperature, and each process requires some additional wattage as compared with utensils in which the heaters are placed in the bottom of the sterilizing chamber. The advantage of uniform distribution of temperature exactly as in the gas heated models more than compensates for the additional current consumption. Starting at ordinary room tem- perature, these sterilizers when electrically heated require about } hour to reach a temperature of 150° C, and about 1 hour to reach a temperature of 172° C, and 1} hours to reach a temperature of 175° C, when drawing 2650 watts. Because of this wattage, they cannot be used on ordinary electric light sockets, but must be connected with a main of suitable capacity. We do not recommend electric heating for the two larger sizes. Each sterilizer is furnished with No. 9525 Thermometer, 200° C. Height Width Depth Equipment Base Shelves Price 1604. Hot Air Sterilizer, American Standard, 12 x 18 x 9 inches Gas Low 1 55.35 1605. ee « i i 5 aaa Elect. 110 v. Hs 1 143.00 1606. “é 6eé “6 “é ce oe cc oe “ce 6c 220 Vv. “ 1 143.00 1607. ae os es ue 18x 24x14 “ Gas fe 2 68.75 1608. ay cate a os oe y ees Elect. 110 v. a 2 183.60 1609. ane Ke se “ a es “220 v. 2 183.60 1610.* ONS pe “ ee 24x30x18 “ Gas “ 3 122.85 1614, rene a z fy 30 x 36x 20) “ as High 3 195.00 * Not illustrated 35 A 7174 1622 HOT AIR STERILIZERS, FREAS ELECTRIC, with automatic temperature control. The general construction is identical with the Freas Type R Incubators and Ovens. The Freas Patent Regulator is the essential feature of these utensils. Its action depends on the expansion of a metallic tube extending from the bottom to the top of the chamber, operating a lever which ‘“‘makes” and “breaks” the contact without arcing. The lever is extended and serves as a pointer operating on a graduated temperature scale on the outside of the sterilizer. When the pointer is set on the scale at the temperature desired, the indicated temperature is approximated with some adjustment. For final adjustment, comparison should be made with the thermometer inside the chamber. The automatic temperature regulation maintains the indicated temperature with reasonable accuracy after the sterilizer has been on the circuit a sufficient time to thoroughly and uniformly heat the walls, and is most satisfactory under continuous operation. With an intermittent use, there is always some loss of time after the indicated temperature is reached before uniform control is attained. A con- siderable time is required to reach maximum heat in common with all electrically heated utensils, and for these reasons the whole construction of the sterilizer is designed for continuous operation. The heating units are wound for 600 watts, therefore, can be connected with ordinary electric lamp socket. No. 7858 Thermometer 0° to 200° C, is included with each sterilizer. These utensils have been approved by the National Board of Fire Underwriters. Height Width Depth Shelves Base Price 1620. Hot Air Sterilizer, Freas Electric, as described above, 110 v. 12 x 12 x 12 inches Zz Low 135.00 1621. to ee os ef ie - “ “ 220 v. “ 2, “ 135.00 1622. “ee “ “ “ ee oe “ 110 v. 18 x 14 x 17 as 4 High 265.00 1623. “e “ce “ec “ec oe ce “cc “ce 220 Vv. oe “ce 4 ce 265.00 1624. Shelves, only, for Freas Electric Hot Air Sterilizers................ 12 x 12 x 12 14x 17 x 18 CI ee eae a eR nent ee Pusey moe nea 1.50 1.75 T7174 Sterilizer, Electric, C. S. & E. No. 34. A double-wall construction of insulating material with inner lining of Russia iron, which insures an even distribution of heated air. Because of the arrangement of the resistance units, this utensil comes to full heat of 200° C within one hour. The automatic electric thermostatic control operates promptly and satisfactorily and within a reasonable degree of accuracy. As 1300 watts are required, this sterilizer cannot be heated from an ordinary light socket, and connection must be made to main supplying 12 amperes. Inside dimensions 10 inches high by 18 inches wide by 10 inches deep. With 6 ft. of heatproof cord, snap switch and pilot Mamapst Mor tl OsvOlts atte exe cicee yen eccecoe een Gates Selig eased en el ceive Rua id eae nm REDS aay a a 125.00 7775. ditto, but for 220 volts..... pve InVobn Ue Rear s Bhan ee eA eR Cn te tts Ror mectec rete DAE ean EN gE 125.00 7776. Heating Unit, for above Sterilizer, canciteing of a lava stone 23 inches long by ? inches diameter, wound with nichrome wire kept in ‘place by fireproof cement. For 1} amperes on 110 volts........ 2.25 T7177. ditto mbut;-fors22 0 VioltSisss kc cencs soni tcoe © ee Seo coud deena alsa ute oves dae Anite ate Ace ak arc render Nd tonal 2.25 1645 1655 1663 AUTOCLAVES OR PRESSURE STERILIZERS 1640. Autoclave—P. C. Pressure Sterilizer, of cast aluminum. This is a household “‘pressure cooker’. For laboratory use, it is furnished with a thermometer holder in addition to the pressure gauge, petcock and safety valve. It can be operated safely to 20 lbs. steam pressure, and dimensions are 73 inches diameter of lid by 93 inches high inside. It can be used on any kind of burner such as Fletcher Radial, ete. With 150° C Thermometer, but without burner................... 21.00 1644. Autoclave—N. I. Pressure Sterilizer, of cast aluminum, 12 inches diameter by 11 inches high; with pres- sure gauge, safety valve and petcock. Equipped with a copper tray inside for convenient handling of test tube baskets. This sterilizer is not furnished with a thermometer tubulation, and the pressure gauge should, therefore, be frequently checked against a reliable thermometer. Sterilizer OMI pee eae nee tern a ame tenia oe ee iti A Ser mie ee nla AAD Dente aE ety behead Pe tre As Say aaieal rend TON AE TA 45.00 1645. ditto, for gas heating, complete with Burner and Enclosed Base as shown in the illustration .. .. 53.25 1646. ditto, but for kerosene heating, with Khotal Kerosene Burner and Enclosed Base.......... . 60.50 1647. Enclosed Base, of sheet iron, 10 inches high, for use with No. 1644 Autoclave................... 7.60 AMERICAN STANDARD AUTOCLAVES—Vertical Pressure Sterilizers, the most widely used and thoroughly satisfactory bacteriological autoclaves, of heavy polished copper tinned inside. Lids of heavy cast bronze, nickel plated, and fitted with steam-tight, ground-in bevel joint, entirely obviating the use of washers. Each autoclave is tested and guaranteed to stand a pressure of 35 lbs. to the square inch, and is provided with a reliable pressure gauge and thermometer reading in both temperature degrees and pounds pressure, and also with a safety valve. Each autoclave is provided with a removable rack or tray to support the test tube baskets at a convenient height above the water. While the hinged lid device is a convenience, we recommend the use of the removable lid on the smaller sizes, as a tight joint can be easily secured when setting the lid by giving it aslight rotary motion with the hands before clamping. This procedure is not possible with the hinged lid. The auto- claves are mounted on an enclosed sheet iron base to protect the burner from drafts. Those listed for gas heating are provided with low form Bunsen burners, and those for oil heating with Khotal Kerosene Burner. The electrically heated autoclaves are supplied with a spiral resistance placed directly in the water. The usual sterilizing pressure of 15 lbs. requires a current intake of 2000 watts for 30 minutes. On this account, these electrically heated autoclaves cannot be used on a lamp socket but must be connected with a main of suitable ca- acity. re For cylindrical test tube baskets of convenient size for use with these autoclaves, see No. 9475. Height Diameter Equipment Price 1655. Autoclave, American Standard, Vertical, as described above, removable lid 12 x 8inches Gas 60.75 ey ee Oil 65.50 Tene ““ “e “ce “ce “ce “cc “e “ce “ce 24 xX 11 “ee Gas 87.75 1658. “ce “ce 6“ “ce “ce “ce “se 46 oe oe “ac ae Oil 92.00 1659. “ “ec be “ec “ce “se “ce “ce oe “ce “ce oe Elec.110 v.139.00 1660. ““ “ce “ce “ “ce “ce “cs ? “cc : “ce ac “ce “cc “cc 220 v.139.00 1661. Autoclave, American Standard, Vertical, as described above, hinged lid Tex 28% Ges oe oe “cs ac “cc “ce “ce oe “a 6e “cs “ce ““ i i in ““ ““ ““ ““ oc oe “ce “ee “ce 24 xX 11 “cc Gas 94.50 1664. “cc “cc “c“ “cc “cc “se “ce “ “cc ““ “ce ““c Oil 98.85 1665. “ce “ “ce ““ “ca “c “ce “ce “ec “se 4“ 6c Elec.110 v.145.75 1666. “cc “c“ “cc 6c 6c “ce “ce “e “6 “ce “oe “a “ 220 v.145.75 1667. ““ ““ “ce oe “ee 6c “ec “a “a 26 xX 14 6“ Gas 121.50 1668. “ac “cc 4c “ce “cc “ce “ce “se “cc 46 “cc “e Oil 126.00 1669. oc“ “ac “ce “ce “es “ce “cc “ce - 46 - Elec.110 v.189.00 1670. “ce “ae “cs “e “cc “cc oe “cb ‘ “ ‘ ‘ “ac 220 v.189.00 A Ss C O M P A N _ Y 1684 1691 S. D. AUTOCLAVES—Heorizontal Pressure Sterilizers. No mechanical fastenings are used to secure the door, and no packing or gasket to make a tight joint, as the steam pressure from within seals the door absolutely. The apparatus is made of heavy polished copper. The steam for sterilizing is generated below the body of the autoclave, and the generator can be heated by any kind of gas, or with steam coil. Where steam coil heating is utilized, the generator must be connected with steam line of at least 20 lbs. pressure. The steam from the line is not introduced into the sterilizing chamber, but is used only in the steam coil as a source of heat for the generator. Length Diameter Diameter of Door Heating Price 1680. Autoclave, S. D. Horizontal, as above described 24 x 21 inches 12 inches Gas 240.00 1681. e i “ te? tek c tee ce re ie Sra 252.00 1682. “ce “cc ce oe “é 4c 28 x 23 “cc 14 oe Gas 340.00 1683. ee “ “ te a xt “ “ “ “ ti Stearn 355.00 1684. ee “ es do 28x26 “ 16 Gas 450.00 1685. “cc “cc “e “ec “cc 6c “ce “cs “cs “sé oe Steam 472.50 Cc. D. AUTOCLAVES—Horizontal Pressure Sterilizers. In this type the door clamps from the outside by rotation of a wheel in front, and on this account is preferred by some to the simpler form described under the preceding numbers. Two shelves are provided, running the entire length of the cylinder, each divided in half so that vessels of different sizes can be readily accommodated. A mercurial thermometer is supplied, this being a particular feature of the autoclaves as arranged for laboratory work. The illustration shows the outfit with gas heated steam generator, which is omitted when the apparatus is furnished for direct steam connection; in which latter arrangement the steam from the line is introduced directly into the sterilizing chamber through a suitable reducing valve furnished as part of the regular equipment. The use of a steam trap in the line is recommended for the purpose of keeping the steam entering the chamber free from dirt, oil, ete., when a direct steam connection is made. This trap is not supplied with the sterilizer and should be furnished by the steam fitter as part of the steam line. 1691. Autoclave, C. D. Horizontal, 30 inches long by 16 inches diameter, as above described, with generator for gas heating.................. seceded tava esas nee RAC reh real ae panne ola i 450.00 1692. ditto, but for direct steam connection, 7. e., with reducing valve, etc., in place of gas gener- DE Ty gachecie erste diet ods date SL Os ere tat oahs a beste ic ctneo aie Tame mea Sees Ie aephneans cone esta dalene le SU aE pans elie dy 425.00 Note—These autoclaves should not be confused with dressing sterilizers of similar appearance, usually made with double-wall construction—necessary in order to keep the dressings dry, a requirement not essential in the sterilizing of culture media, where it is the prac- tice to insure the dryness of the contents of the sterilizer by cutting off the steam a little time before sterilizer is opened. 38 1706 __ ARNOLD STEAM STERILIZERS. Arnold Steam Sterilizers are made of heavy polished copper with a quick steaming base which is automatically supplied with water from an open reservoir above. The water in this reservoir never boils, is always in view, and can be replenished without any interruption of the steaming process. From the reservoir the water passes through small apertures into the quick steaming base, to which the heat is applied. As the base will contain only a thin layer of water, steam is produced very rapidly, and rising through a funnel in the center of the apparatus passes to the sterilizing chamber. Here it accumulates under slight pressure at an unvarying temperature of 100° C, and this temperature can be maintained indefinitely without any attention to the apparatus except an occasional replenishing of the water in the reservoir. The excess of steam in the sterilizing chamber escapes around the cover and is confined under a hood, thus forming a steam jacket around the outside of the sterilizing chamber which very effectually aids in the maitenance of a uniform temperature within the chamber. As the steam is finally forced down from above and comes in con- tact with the air, it condenses and drips back into the reservoir. The rectangular, or so-called Boston Board of Health Form, offered in three single and one double door size, was first suggested by Prof. W. T. Sedgwick, of the Massachusetts Institute of Technology, and has been widely used in bacteriological laboratories for many years. While these sterilizers can be heated by any kind of burner for source of heat, we recommend for labora- tories where gas is available the enclosed sheet iron support, or stand, and Fletcher Radial Burner. The cylindrical forms, or so-called General Purpose Sterilizers, are also used as dressing sterilizers in hospital laboratories. We stock them only in copper because of the dissatisfaction which has resulted from the tin construction because of the early corrosion and rusting in laboratory work. No special stand or burner is regularly supplied with these sterilizers because of their adaptability for any form of heating. Both forms are supplied with two removable trays or shelves. Height Width Depth Door Equipment Price 1700. Sterilizer, Arnold, Rectangular 133x 9 x 9 inches Single Stand and burner 75.00 1701. “cc “cc “ee “cc “ce “ee oe “se None 67.50 1702. i a x 154x124x12} “ ie Stand and burner 81.00 1703. me as is ee 2 2 ee SS None 73.00 1704. fe ." a 194 x163x144 “ a Stand and burner 129.00 1705. os a0 if ee Sa i = None 121.50 1706. < - 154x 244x123} “ Double Stand and burner 154.50 1707. ue a 2 a % os None 144.00 Dimensions Equipment Price 1710. Sterilizer, Arnold, Cylindrical, of copper, as described above 114 x 103 inches None 31.50 1711. <3 3 oy ne s ee e “ 124x103; “ e 33.25 | | We attend carefully to the accurate preparation of invoices and other export documents as required | by Customs regulations in foreign countries, and pack the merchandise in strong and rugged iron- | bound cases. No claim of consequence for breakage or loss in transit in export shipments has ever been received by us. Many foreign scientists engaged in laboratory work unfamiliar in pre-war years with our facilities | for exportation have expressed appreciation of our services and satisfaction with the quality of our | goods, and have shown an increasing tendency to purchase in the U. S. since the close of the war. 39 A R T H U_ R H. T H O M A §S Cc O M P A N Y A SEROLOGICAL APPARATUS | 4 1720 1723 1720. Serological Bath, for Inactivations at 56° to 60°C. With thermometer, thermo-regulator, Koch safety _ burner, and necessary stoppers and UDINE se aun eatisece res re ele ae ae ann Seah eae hats 31.50 1721. ditto, but without thermometer, thermo-regulator, burner, stoppers or tubing.............. 19.50 1723. Serological Bath, Kolmer, for Incubations at 373° to 40°C; of polished copper, on enclosed sheet iron base, outside dimensions 32} inches long by 14} inches high, with bath proper 5 inches deep. Very constant temperatures can be maintained in this bath without the use of any form of thermo- regulator. In the author’s technique there are used three special galvanized wire baskets as shown in illustration and listed below. Without racks, but with two thermometers, two low form Bunsen burners, necessary stoppers and tubing and removable cover of polished copper not shown in its brAGLON= Cac aa chee ee ede cate ea eal ees gt He OOM ae aes amen ee mec GU wae Sonus ne gehen 49.05 1724. ditto, but without thermometers, burners, stoppers or tUbING 25 A eee 44.55 1725. Test Tube Rack, Kolmer, of galvanized wire, 93 x 33x 23 inches; takes 48 tubes up to about 16 mm ALLTEL CEA. coe: eect ees pd. Gott athe SSS PND NEUEN pie Blcoe Heaters t etiein lars Seger Shs 1.00 1726. ditto, 93 x 5! x 23 inches; takes 72 tubes up to about 16 mm diameter .................... 1.20 1727. ditto, 91 x 91 x 23 inches; takes 144 tubes up to about 16 mm diameter................... 1.50 1728 1730 1728. Serological Bath, for incubation or agglutination, double wall, of heavy copper tinned inside. The glass doors are set at an angle, preventing the dripping of condensed moisture into the tubes during haemolysis, and also for convenient observation. With four Test Tube Supports; but without thermometer, thermo-regulator or burner........ 00.0.0... ccc ete ee 87.75 1729. ditto, but complete with Thermometer, 100° C, Thermo-regulator and Burner............... 91.35 1730. Combined Serological Unit, for simultaneous inactivation and incubation. The upper compartment operates at 56° C for inactivation, and the lower compartment at 373° C for incubation or agglu- tination; both connections being to the same cord and plug. Each compartment is supplied with independent regulator and heating units. A small paraffine bath “B” with inset “D” is supplied for use in the inactivating chamber as in the method of the U. S. Army Medical School. One thermometer can be inserted directly into the paraffine. The outfit is regularly furnished with three Thermometers, Paraffine Bath, and eight Test Tube Racks, as shown in the illustration. The inside dimensions of the incubating chamber are 15 by 12 by 10 inches, and of the inactivating compartment 9 by 7 by 7 inches. For use on either 110 or 220 volt circuits by the simple inter- Ghang@evOl PUGS: ..iosons eee pede vii te Seen das anu He A cle oes ao ate ated ia See nie Ne eee neem 133.80 1731. ditto, but without Paraffine Bath and Test Tube Racks. With three thermometers.... .. . 99.00 1732. Paraffine Bath, for inactivations, consisting of bath ““B”’ with removable inset “D”............. 12.40 40 1737 1738 SEROLOGICAL BATHS, C. 8S. & E. GABLE TYPE, for Electric, Oil and Gas Heating. Of heavy tinned copper on the inside and insulated on the outside with a thick wall of transite. The gable type covers have been found a very satisfactory means of preventing the dripping of condensed moisture into the tubes during haemolysis. A Pencil Type Thermostat is used for the regulation of the electrically heated baths, and a pilot lamp indicates when the current is on or off. A snap switch controls part of the heating units for the purpose of changing the temperature of the bath from 373° C, as required for incubation and agglutination, to 56° C if bath is to be used for inactivation. In the oil heated baths a thermostatic capsule is employed for control, and this can only be used for tem- peratures in the neighborhood of 373° C. The illustration shows the oil heated attachment, the gas heated being identical with the exception that a gas burner is installed in place of the oil lamp. The 10-rack bath can be furnished with oil or gas heating on special order, but is not so carried in stock. The test tube racks supplied are our No. 9493 U. S. Army Medical Dept. Model, with a capacity of 20 tubes, and with each pair of holes numbered from 1 to 10. The holes in these racks are 14 mm diametér. Length Width Depth Equipment Racks Price 1736. Serological Bath, C. S. & E. No. 97 13 x 10x 6 inches Gas 4 80.00 1737. « ‘6 "OF « 7 eta Oil 4 80.00 1738. % x “ 93 ‘ Steen Ae Elect. 110 v. 4 85.00 1739. “ee “ce oe “ee 84 33 x 103 x 6 “ce “cc 6“ 10 140.00 1742. Serological Bath, Hearson Gable Type, for Gas Heating, with Hearson Patent Capsule control, exactly as used on Hearson Incubators. Of heavy copper construction throughout. The racks hold 36 tubes, with three rows of holes 12 mm diameter, numbered consecutively from 1 to 36. The racks are specially made for this bath and are not carried in stock among our test tube racks. With Expan- sion Capsule 35° C. Because of the great satisfaction derived from the Hearson capsule, this type of Wassermann Bath is in wide and satisfactory use in laboratories throughout the U. S. Inside dimensions 14 by llinches. Capacity 4racks. Complete with four No. 1745 Racks. 141.75 1743. ditto, but with inside dimensions 21 by 11 inches. Capacity 6 racks. Complete with six No. SL Fi PCIE ase oe atc ste ars ia PN nee rere edocs SONAE SeP IN calcd es ce stated Bs floes Wea secant eat vad eel 178.50 1744. Capsules, Hearson Patent Expansion, 1} inch square, for use with Hearson Serological Baths. 374° Range ©entigraden tcc ccrnire waists: «.sethart teh iis 4 okteue abeaera diac etbeanermenararalmar es eas a 373 55° Bea Bio ces is ocsce eea ehcbig elie ese ted ates otis Res Needy talents Bases Ties . 1.50 1.50 1745. Test Tube Rack, for Hearson Serological Baths, with 36 holes in three rows. Each hole is 12 mm diam- eter and numbered consecutively from 1 to 36............. 00.00. cee ee 8.25 41 1756 In use for oil heating. 1750 Showing Paraffine Embedding Bath and Test Tube Rack removed. SEROLOGICAL BATH, U. S. Army Laboratory Model. This is the most recent modification of the large Wassermann Bath originally described in Bulletin 8, Surgeon General’s Office, ‘“‘The Prevalence of Syphilis in the Army,” by Captain Edward B. Vedder, and embodies all of the modifications developed during the war. It has a capacity of twenty No. 9493 U.S. Army Wassermann Racks, and is intended for work where a great many re- actions are to be handled. The water bath proper measures 30 by 23 by 12 inches deep, and provides for the use of a very large volume of water with the resulting ease of temperature control. When the utensil is gas heated, two micro burners are sufficient to keep it at the incubating temperature of 373° C. A Roux Bimetallic Regulator is used for control. The electric heating equipment is controlled by a C. S. & E. Regulator No. 9662, and is supplied with necessary connections to operate on either 110 or 220 volts by connecting the resistance either in series or multiple. The bath proper is of tinned copper and is encased in sheet iron. The lids are double walled, the top being flat with the inner surface slanting to the rear in order to carry off the condensation and prevent it from dripping into the tubes during haemolysis. A constant water level device is provided which controls the water level when connected to the water supply—the use of this feature, however, is optional. 1750. Serological Bath, U. S. Army Laboratory Model, with equipment for both gas and electric heating. Complete with Thermometer, 100° C, Thermo-regulator, two Micro Gas Burners, twenty No. 9493 Wassermann Racks, and electric attachments. ..........0.0 000000000 cece eee 242.00 1756. Serological Bath, U. S. Army Field Model, ‘or Oil Heating; designed for use with the American Expeditionary Forces in France. The bath, fitted with a thermo capsule for 874° C, may be used for agglutination tests, Wassermann tests, etc., or with capsule for 56° C, for inactivating sera, meningococcus agglutinations, etc., and for use with No. 1758 Paraffine Embedding Bath for histo- pathology. The capsules can be changed ina moment. A small gas burner may be used too with the bath in lieu of the oil lamp, where gas is available. Complete with oil lamp, two capsules, thermo-regulator and eight No. 9494 Test Tube Racks, but without Paraffine Embedding Bete liga sak a axe scars Pa nya ced SON reall ronan renga atemeat a deta Ue reac lea a Mims a) clone, Cae eg RGA Pe 100.00 1758. Paraffine Embedding Bath, U.S. Army Field Model, for use in No. 1756 Serological Water Bath. Designed for use with the American Expeditionary Forces in France to meet the need for a bath in which a constant temperature of 58° to 59° C could be maintained without adding a separate thermo- regulating device. It is inserted in the serological water bath with the end distal to the thermo- regulating device, and consists of a square copper bath containing nine copper buckets filled with paraffine for embedding. As this bath is inserted directly over the lamp heating the water bath, and as the water in it does not circulate with that of the water bath, a constant temperature of 3° higher than that of the main bath is maintained. This gives a temperature of 58° or 59° in the paraffine bath while the remainder of the water bath stays at 56°, and can be used synchron- ously for agglutination tests, inactivating sera, or accomplishing other serological work requiring a temperature of 56° C. With nine nickel-plated embedding cups..................... 92.00 9494. Test Tube Support, or Wassermann Rack, of copper, with. 20 openings in two parallel rows of 10 each, to take tubes up to 13 mm diameter. The front openings are numbered from 1 to 10, and the racks are numbered serially from 1 to 8. As used in No. 1756 Serological Water Bath............. 2.50 42 A 1760. 9495. 1762. 1764. 1766. 1760 1762 1764 1766 Serological Bath, Electric, C. S. & E. No. 51, for incubation and agglutination, also inactivation. Of heavy copper tinned on the inside and insulated on the outside with a thick layer of transite. The heating units are in a metal box in the bottom of the bath, and a No. 9656 Pencil Type Thermostat is installed parallel with the heating units for regulation of the temperature. A pilot lamp indicates when the current is on or off, and a snap switch controls part of the heating units for the purpose of changing the temperature of the bath from 373° C to 56° C, if such change should be desired. Inside dimensions 9 by 9 by 5 inches. Price includes two adjustable metallic Test Tube Racks, each rack having a capacity of 48 test tubes 75 by 11mm. With cord and plug; for 110 volts. 65.00 Test Tube Rack, Wassermann, of nickel-plated brass with adjustable supports for suspension in water bath. Capacity 48 test tubes 75 by 11mm. Dimensions of rack 9 by 4 by 2} inches high; height OVER al Sin Ches ek: oi ease Sask occ a cree ar oto se we a ee ae ah nad Sea ae ne EN a GAG Pe Bice 5.50 Combination Serological Bath, Electric, C. S. & E. No. 76, for simultaneous incubation and inactivation, consisting of two compartments carefully insulated from each other, each with its own heating and regulating equipment, so that when connected on the same socket the incubating compart- ment operates at 374°C., and the inactivating compartment at 56°C. The large compartment for incubations is 14 x 103 x 5 inches deep, and takes six No. 9493 Test Tube Racks; and the small compartment for inactivations is 43 x 103 x 5 inches deep, and takes two of the same racks. A pilot lamp is supplied for each compartment to indicate when the current is on or off. Complete with support, two thermometers, eight test tube racks and cord and plug. For 110 volts.. 150.00 Serological Bath, Porcelain. This electrically heated and controlled water bath operates at 373° or 56° C, for either inactivation or incubation. Either temperature is secured by a simple turn of the controlling snap switch. An electric heater entirely surrounded by water, and extending the full length of the bath, is used. The control thermostat is of the multiple contact type, capable of repeated heating and cooling without changing the adjustment. An adjustment screw permits change to other temperatures, if desired. The inside dimensions are 123 x 6 x 5 inches. With one wire shelf on which Wassermann Racks such as No. 9493, or other test tube racks are supported in the water immediately above the heating unit. The glazed porcelain has been found economical, rugged and of pleasing appearance when used for this purpose. Without Wassermann Racks, test tubes or thermometer; for use on 110 volt a.c. or d.c. circuit..................0000. 60.00 Paraffine Compartment Tray, for Wassermann Inactivations, U. S. Army Medical School Model. This is the latest development of the paraffine bath described in Bulletin 8, Surgeon General’s Office, “The Prevalence of Syphilis in The Army,’ Captain Edward B. Vedder; and designed for use in an incubator or other constant temperature apparatus of suitable size. Dimensions 10 by 10 by 4 inches deep, with 21 compartments 2 inches square, and 2 compartments 2 by 4 inches; with dividing wall between the compartments continued only to within } inch of the bottom so that paraffine may flow readily from one compartment to the other and maintain a constant temperature at the same level in all compartments. Of heavy polished copper, with two handles and device for lifting out test tubes. The tray containing the compartments is removable, so that bath may be-1sed for other Purposes ssi.) 5 scene aia dceecord tusks Gore eanee Soe wre eR ecer ee a na a) ge natan ee Seay aa 24.20 1780 =. ‘ i , a | Ii t 1790 (Described on page 45) PARAFFINE EMBEDDING OVENS, Double Wall. Of heavy polished sheet copper, on enclosed sheet iron base 8 inches high, with an extra sheet iron bottom to prevent burning out, and with asbestos mat. These ovens have tubulations for thermometer and gas regulator, and two perforated, removable shelves. The gas heating equipment consists of No. 2562 Burner, 7 inch, No. 9525 Thermometer, 100° C, and No. 9636 Thermo-regulator. Height Width Depth Equipment Concentric Rings Price 1770. Paraffine Embedding Oven, as above described, 8x 10x 9 inches None None 26.40 1771. “ “ peeaey i Pe Beet ee Tee mice Gas heating cs 30.40 1772. oe “ce oe sé oe 6c “cc “ce “ce “ce None With 29.60 1773. “e “e “ec oe oe ce “ce “e “ce 6e Gas heating oe 33.60 1774. a net a 10 x12x10 “ None None 32.00 1775. “ és ti, He i “ raise ae Gas heating ee 36.00 1776. “cc “cc “cc “e oc “ec “ce “cc “cc “ée None With 35.20 1777. oe ce 6é “ce “ “ “ z9 “ce “cr Gas heating “cc 39.25 PARAFFINE EMBEDDING OVENS, Hearson. These utensils are identical with Hearson Bacterio- logical Incubators No. 1440, with the addition of Expansion Capsule “E,” 55° C, and two extra shelves, the latter being supplied because of the smaller receptacles used for paraffine. The utensil purchased as a Paraffine Embedding Oven can be used equally well as a bacteriological incubator by substituting the lower temperature capsule, which is also suitable for work with lower melting paraffines. Width Depth Height Equipment Shelves Price 1780. Paraffine Embedding Oven, Hearson, as above described, 9 x 9 x 12 inches Gas 3 90.40 1781. ie “ te es dae ieee “ Ge tas eae et Oil 3 90.40 1782. 3 pe = a cee is ea dati as Electric 110v. 3 100.65 Note—Where larger ovens are desired, it is only necessary to use Incubators with higher temperature capsules. PARAFFINE EMBEDDING OVENS, Electric, C. S. & E., identical with Nos. 1515 and 1470 Incubators, except that they are furnished with Nos. 9675 and 9673 Heating Plates respectively, in order to secure tempera- tures in the interior compartment up to 60° C, for hard paraffines, and that they have two shelves instead of one, because of the smaller size of the paraffine receptacles. 1786. Paraffine Embedding Oven, CG. S. & E, as above described, 15 x 12 x 103 inches, for 110 volts... 69.00 1787. s 26x18x18 “ SOTO.) .106.50 1790. Paraffine Receptacle, C.S. & E. No. 38. This is the metallic inset particularly designed for use in C. S.& E. Paraffine Oven No. 1787, but suitable for use in any incubator or other constant temperature device with sufficient internal space to accommodate the receptacle, which is 13 inches high by 14 inches wide by 14 inches deep. The three legs are removable and the top and bottom are of transite 3 inehes thick. The five shelves of perforated metal are provided with nine holes 2; inches diameter, taking metallic cups 1} inches deep, 45 of which are supplied with each receptacle.. .50.00 7766. Embedding Oven, Sargent Patent Electric, as more fully described on page 463. Found in practice to be very convenient for embedding because of the range of the automatic temperature control which is from room temperature to 160° C. With cord, plug and thermometer, for 110 volts......... 35.00 44 1806 1804 1791. Embedding Oven Vacuum, Hearson, for Gas Heating (illustrated on preceding page) consisting of a water bath with a heavy copper paraffine bath 7 by 43 inches, with thick plate glass lid made air-tight by means of a rubber ring. The apparatus may be used as an ordinary embedding bath, 7. e., with- out exhaustion, or the paraffine bath proper may be exhausted by a few strokes of the air pump. The removal of all volatile reagents in which tissues have been soaked preparatory to embedding is very much hastened by the use of this method. The control of the water bath is by Hearson Capsule No. 1792, 46° C. Air Pump No. 1015 is suitable for use with this outfit, but is not included in the price. Price includes thermometer, flexible metallic tubing and burner.... 50.00 1792. Capsule, Hearson Patent Expansion, 14 inches square, for use with preceding Vacuum Embedding Oven; /PFange: 465 Ce..c 2 8s.5 gale boat he ied Sede a Geode wales be Sabre inen es Sch van plane see ae 1.50 Paraffine Embedding Oven, Lillie, of polished copper, triple wall construction, with eight drawers 10x 4 x 3} inches with sides and back of perforated zinc. Two paraffine receptacles are provided with screw tops and stopcocks; also 12 perforated trays for drying and fixing. The enclosed base is 15 inches high and total outside dimensions 23 inches wide, 25 inches high, 153 inches deep. The gas heated equipment consists of Greenman burner, Greenman thermo-regulator and a thermometer. Oil heating equipment and electric heating equipment are as supplied with American Standard Incubators. 1794. Paraffine Embedding Oven, Lillie, as above described, without equipment.................... 209.00 1795. ditto, with gas heating equipment.............. fe ee eee ee ; 240.50 1796 2 “oil a Re da yA wee eee ; De kh fee .. 276.75 1797. ue “electric “ Ss Fea ene the sere eh tet ales Phatis Don x es PLR eee . 304.75 1800. Embedding Table, Ransom, Electric. For heating slides to a temperature just below the melting point of paraffine, which gives maximum flattening without damage to the section. Consists of a tran- site block 24 inches long by 6 inches wide mounted on a brass frame 3 inches high, with electric heating and control. With paraffine of 55° melting point, the thermometer should read 43°C, as the thermometer is mounted below the transite block and registers a temperature somewhat lower than that on the upper surface. Will accommodate 40 slides at one time. With cover to protect the slides from dust, and cord and plug. For 110 volts................... 40.00 1801. GiGbOMsWItH OU COVER 2a reste cen eesvetio cies tyes Senta ae tthe once Aste Maytea. aunt det encdsee Amma aera Homen Gee Pons _... 35.00 1802. Pilot Lamp, only, for use with preceding Paraffine Embedding Table............ bei wie ees acai -90 1803. Thermometer, Angle, range 0 to 100° C, for use with preceding Paraffine Embedding Table....... 1.75 1804. Embedding Table, Electric. Sufficient heat is given off at the warm end of the table to melt paraffine of the highest melting point used for embedding. By moving the dish away from this end any desired temperature is available. A separate cold table disconnected from the heating plate is provided for the final setting. Mounted on a substantial base, 16 by 63 inches, with leveling screws, and with cord and plug. For 110 volts............0 0000.22 15.60 1805. Embedding Table, Huber, with top of heavy copper 14 x 4 inches wide, for drying micro sections, etc. Also used as a warming table for fixing blood films, etc.................000...000000...0000, 2.15 1806. Embedding Table, consisting of a triangular copper plate 16 inches long by 72 inches wide at the large end, with small copper box for containing the paraffine. By heating the plate at the acute end, varying degrees of temperature are readily obtained throughout the length of the table...... 3.50 45 1818. 1820. 1822. 1824. ae ff re | i , J Ice Chest, made of galvanized sheet steel, finished in white enamel inside and outside, with walls insulated with a layer of sanitary quilt. The ice chamber is easily removable without disturbing the other compartment in order to empty the water. A perfect circulation of air keeps the contents dry and evenly cold. Dimensions, 24 by 14 by 14 inches deep. Ice capacity, 25 lbs............. 17.00 Refrigerator, Biological, constructed of galvanized steel and finished in white enamel inside and outside. The ice chamber is 13 by 133 by 14 inches, with an ice capacity of 65 lbs. The storage chamber is 20 by 13 by 17% inches, and the over-all outside dimensions are 44 by 164 by 21 inches wide. Under ordinary working conditions a temperature of from 7° to 10° C is readily maintained in the reirigerating-Comparcment ye vcs ueee eee is ae eee thet aps ones es eas eS Be ta A NR Chain ep ne a nee 36.50 Refrigerator, Biological, especially designed to meet laboratory requirements. Made of hot galvanized steel with baked-on white enamel finish both inside and outside. The ice chamber at top, on one side, has a capacity of 100 lbs. Underneath the ice box is a compartment 19} by 15 by 113 inches. The compartment opposite the ice chamber is 15 by 1234 by 18 inches; beneath which are two drawers each 183 by 12} inches, each drawer divided into two compartments. Under ordinary working conditions a temperature of from 7° to 10° C is readily maintained in the refrigerating COMPATCIMEN Gas see el is a Peres ine ethene eM aes la See ee ane wee eae Soa unl Sh Ame A eA ou nee toy Freezing Closet, for operation at temperatures as low as —12° C, by means of freezing mixture of salt and cracked ice. This freezing closet is not to be confused with ordinary refrigerators in which such low temperatures are not obtainable. The inside compartment is of heavily tinned copper, as is the inside lining of the outer box, which is constructed of heavy galvanized sheet iron with aluminum finish on the outside, and tinned copper on the inside, with cork insulation between. A 6-inch space is provided on top of the interior compartment for the salt and ice mixture, and a 2-inch space around the other sides and on the bottom. A brass draw-off spigot is provided. The interior compartment is 12 by 12 by 14 inches high, and is provided with two shelves. On angle iron:standOnches hightei. a cqarss cube weve aan verre ta tae ate oe doa anh n bese lacyin aerate 90.00 TROEMNER ANALYTICAL BALANCE NO. 35 MADE BY HENRY TROEMNER EXCLUSIVELY FOR ARTHUR H. THOMAS COMPANY Engraved with the names of, and guaranteed by both maker and dealer 1840—Troemner No. 35 TROEMNER ANALYTICAL BALANCE No. 35; a balance of rugged and robust construction and of simple design, intended primarily to meet the requirements of educational laboratories in quantitative analysis in competition with low-priced balances hitherto imported from Europe. The simple and durable construction has so commended this balance to industrial chemists as to make our sales to industrial laboratories equal those to educa- tional laboratories. There is no analytical balance of equal merit obtainable at the present time at so low a price. In the sale of over 1500 of these balances, most of which are in daily use, we have never met with a single expres- sion of disapproval or dissatisfaction on the part of the purchaser or user, and in many instances we have received continued repeat orders from the same laboratory. 1840. Sensitivity—1/5 milligram with full load, 7. e., a change of weight of 1 milligram on the beam deflects the pointer on the scale a least 1 division and, without load, a change of weight of 1 milligram on the beam shows a deflection of the pointer of a least 2 divisions. This is a practical working sensitivity; some variation in this adjustment may be effected in the labora tory by shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system. Capacity—200 grams in each pan. Case—Of seasoned mahogany with counterpoised front door. Baseboard of case is without drawer but the unusual roominess of the case permits ample space for manipulation of both charge and weights and for the convenient storage of the latter. Outside dimensions over all, 17 inches wide, 16 inches high, 9 inches deep; inside dimensions 1434 inches wide, 1234 inches high, 614 inches deep. Central Pillar—Of brass, oxidized black, with two vial levels in base. These are unleakable and much superior to the round form of spirit level. Beam—Of Bint 634 inches long, with oxidized black finish. Graduated on right-hand side from 0 to 10 mg in 1/5-mg divi- sions, the graduations being in white on black background. Rider Carrier—Of simple and effective construction, which has proved free from any possibility of derangement. Knife Edges and Planes—Of agate throughout. Release and Arrest—The beam and hangers are released by an improved single action device making the contact of the center knife edge simultaneous with the contact of the end knife edges and bearings. This construction is simple and rugged, engaging and supporting the beam and hangers free of any contact with the knife edges and bearings, thus preventing any possible injury while loading and unloading the pan. 7 Pointer Scale—Of ivory, recessed so that the end of the pointer moves in the offset in the same vertical plane as the division on the scale, thus avoiding errors of parallax. Pan Arrest—Of the self-locking, adjustable push-button type. Pans—Of polished German silver, 2/4 inches diameter. _ Arches—Of hard drawn polished German silver wire with a 4-inch spread. Riders—Each balance is furnished with two 10-mg riders. Balance, Analytical, Troemner No. 35, as above described, without weights but with two 10 mg riders 50.00 47 A RT -He UL eR H. T H O M A _ S Cc O M P A N Y TROEMNER ANALYTICAL BALANCE NO. 50 MADE BY HENRY TROEMNER EXCLUSIVELY FOR ARTHUR H. THOMAS COMPANY Engraved with the names of, and guaranteed by both maker and dealer a Som w oat 1842—Troemner No. 50 TROEMNER ANALYTICAL BALANCE No. 50; a balance designed particularly to meet the require- ments of industrial chemists which, by its rigid and robust construction, has been found to stand the wear and tear in a works laboratory in a remarkable manner, and which has become the standard American moderate- priced analytical balance. In the sale of over one thousand of these balances, most of which are in daily use, we have never met with a single expression of disapproval or dissatisfaction on the part of the purchaser or user, and in many instances we have received continued repeat orders from the same laboratory. Our deliveries of this balance have been limited only by the productive capacity of the maker rather than by the demand, which has always been in excess of our stock. 1842. Sensitivity—1/10 milligram with full load, 7. e., a change of weight of 1 milligram on the beam deflects the pointer on the scale at least 2/4 divisions and, without load, a change of weight of 1 milligram on the beam shows a deflection of the pointer of at least 319 divisions. This is a practical working sensitivity; some variation in this adjustment may be effected in the laboratory by shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system Capacity—200 grams in each pan. ‘ Case—Of French polished mahogany with counterpoised front door. The base is fitted with a drawer and with four leveling screws. Outside dimensions over all 17 inches wide, 1815 inches high, 834 inches deep; inside dimensions 1434 inches wide, 1214 inches high, 6 inches deep. a : Central ee ees brass, with two vial levels in base. These are unbreakable and much superior to the round form of spirit level. Beam—Of aluminum alloy, 7 inches long, with oxidized black finish. Graduated on right-hand si i @ divisions, the graduations being in white on black background. . de from 0 to 5 mg in 1/10-mg Rider Carrier—Of simple and effective construction, which has proved free from any possibility of derangement. Knife Edges and Planes—Of agate throughout. Release and Arrest—The beam is supported by a three-point rigid beam arrest that has a fall-away action and releases the beam so that the contact at the center knife edge is coincident with the contact at the end knife edge, thereby avoiding all jarring and possible injury to the knife edge by a sudden shock. Pointer Scale—Of ivory, recessed so that the end of the pointer moves in the offset in the same vertical plane as the division on the scale, thus avoiding errors of parallax. Pan Arrest—Of the self-locking, adjustable push-button type. Pans—Of polished German silver, 2! inches diameter. Arches—Of hard drawn polished German silver wire with a 334-inch spread. Riders—Each balance is furnished with two 5-mg riders. Balance, Analytical, Troemner No.5), as above described, without weights but with two 5 mg riders 85.00 48 A R T H U_ R H. T H -O M A Ss CO M PP A N ¥ TROEMNER ANALYTICAL BALANCE NO. 65 MADE BY HENRY TROEMNER EXCLUSIVELY FOR ARTHUR H. THOMAS COMPANY Engraved with the names of, and guaranteed by both maker and dealer 1844—Troemner No. 65 TROEMNER ANALYTICAL BALANCE No. 65; a balance identical with Troemner No. 50 in every way with the exception of the beam, which is divided on both sides of the central knife edge from 0 to 5 mg in 1/10 mg divisions instead of on the right-hand side only as in the No. 50, and with the addition of a polished black plate glass base inside of the case. Sensitivity—1/10 milligram with full load, 7. e., a change of weight of 1 milligram on the beam deflects the pointer on the scale at least 214 divisions and, without load, a change of weight of 1 milligram on the beam shows a deflection of the pointer of at least 314 divisions. This is a practical working sensitivity; some variations in this adjustment may be effected in the laboratory of shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system. Capacity—200 grams in each pan. Case—Of French polished mahogany with counterpoised front door and with a polished black plate glass base inside of the case. The base is fitted with a drawer and with four leveling screws. Outside dimensions 17 inches wide, 181% inches high, 834 inches deep; inside dimensions 1434 inches wide, 1214 inches high, 6 inches deep. Central Pillar—Of lacquered brass, with two vial levels in base. These are unbreakable and much superior to the round form of spirit level. Beam—Of aluminum alloy, 7 inches long, with oxidized black finish. Graduated on each side of the central knife edge from 0 to 5 mg in 1/10-mg divisions, the graduations being in white on black background. Rider Carrier—Of simple and effective construction, which has proved free from any possibility of derangement. Knife Edges and Planes—Of agate throughout. Release and Arrest—The beam is supported by a three-point rigid beam arrest that has a fall-away action and releases the beam so that the contact at the center knife edge is coincident with the contact at the end knife edge, thereby avoiding all jarring and possible injury to the knife edge by a sudden shock. Pointer Scale—Of ivory, recessed so that the end of the pointer moves in the offset in the same vertical plane as the division on the scale, thus avoiding errors of parallax. Pan Arrest—Of the self-locking, adjustable push-button type. Pans—Of polished German silver, 24 inches diameter. Arches—Of hard drawn polished German silver wire with a 334-inch spread. Riders—Each balance is furnished with two 5-mg riders. Balance, Analytical, Troemner No. 65, as above described, without weights but with two 5 mg riders 105.00 49 1844. A R T H UR H. T H O M A 5S Cc O M P A N _ Y TROEMNER ANALYTICAL BALANCE NO. 10 For twenty-five years the leading American balance for continuous and precise analytical work; over 5,000 in actual use inl iat BE wists 1846—Troemner No. 10 TROEMNER ANALYTICAL BALANCE No. 10; a world-famous balance of a construction original with Henry Troemner, Philadelphia, on designs suggested by Mr. A. A. Blair, and for twenty-five years perhaps the most widely used high-grade analytical balance in many industrial laboratories, particularly in the iron and steel industry. From the standpoint of sensitivity, simple construction and durability, we recommend this balance for continuous and precise analytical work. Sensitivity—1/20 milligram with full load, 7. e., a change of weight of 1 milligram on the beam deflects the pointer on the scale at least 5 divisions and, without load, at least 6 divisions. This is a practical working sensitivity; some variation in this adjustment may be effected in the laboratory by shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system. Capacity—200 grams in each pan. Case—Of old, well-seasoned mahogany, French polished; the top of base is covered with a black plate glass; the front sash is counter- poised, and the rear sash also slides up, allowing the weighing of long objects extending beyond the outside lines of the case; outside dimensions 19 inches wide, 19 inches high, 11 inches deep; inside dimensions 1614 inches wide, 13 inches high, 634 inches deep. Central Pillar—Of brass, gold plated Beam—Of aluminum alloy, cold rolled, and having more than three times the tensile strength of pure aluminum. The rolling is done under high pressure, eliminating all invisible defects in the mass and providing uniform density throughout the sheet This beam will maintain its adjustment over a wide range of temperature change. It is 7 inches long, is finished in a non-corrosive black with white divisions in 1/20 milligram on each side of the central knife edge. Rider Carrier—Of simple and effective construction, which has proved free from any possibility of derangement. Knife Edges and Planes—Of Russian agate throughout. Release and Arrest—Releasing arms are of the simplest construction, there being but three principal parts. These swing up to hold the beam and down to release it, being operated by turn button in front of the case. They are so constructed as to bring their axis coincident with the contact line at the center knife edge and hold the beam firm and secure when the balance is being loaded and unloaded. This is a distinct and distinguishing feature of this balance. Pan Arrest—Of the self-locking, adjustable push-button type. Pans—Of aluminum, 3 inches diameter, adjustable on the arches. Arches—Of cold drawn nickel silver, gold plated, with a 5-inch spread. Riders—Each balance is furnished with three 5-mg riders. Finish—All brass parts are heavily gold plated as a protection against all possibility of corrosion. Balance, Analytical, Troemner No. 10, as above described, without weights but with three 5 mgriders 198.00 50 A R T H U_ R H. TH O M A Ss CO M P A NY TROEMNER ANALYTICAL BALANCE NO. 6 Specifications identical with Troemner No. 10 except as to length of beam, dimensions of case, and other points involved in the larger capacity a 1848—Troemner No. 6 TROEMNER ANALYTICAL BALANCE No. 6. The frequent requirement of a heavy load and great sensitivity is met most satisfactorily in this balance up to its capacity of 500 grams. As will be noted below, the general specifications are identical with the Troemner No. 10 balance except as to the length of beam, dimensions of case and other points involved in the larger capacity. Sensitivity—1/10 milligram with full load, 7. e., a change of weight of 1 milligram on the beam deflects the pointer on the scale at least 2 divisions and, without load, at least 2!4 divisions. This is a practical working sensitivity; some variation in this adjustment may be effected in the laboratory by shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system. Capacity—500 grams in each pan. Case—Of old, well-seasoned mahogany, French polished; the front sash is counterpoised, and the rear sash also slides up, allowing the weighing of long objects extending beyond the outside lines of the case; outside dimensions 24 inches long, 23 inches high, 1114 inches deep; inside dimensions 21 inches long, 17 inches high, 7!2 inches deep. Central Pillar—Of brass, gold plated. Beam—Of aluminum alloy, cold rolled, and having more than three times the tensile strength of pure aluminum. This beam will maintain its adjustment over a wide range of temperature change. It is 12 inches long, is finished in a non-corrosive black, and graduated in white divisions from 0 to 10 mg in 1/10-mg divisions on each side of the central knife edge. Rider Carrier—Of the double pattern, worked from either side of the case, and of simple and effective construction, which has proved free from any possibility of derangement. Knife Edges and Planes—Of Russian agate throughout. Release and Arrest—Of the simplest construction, the axis of the swinging arms is always coincident with the contact line at the center knife, making the action free and effective and holding firm and secure when the balance is being loaded or un- loaded, as the lift is just sufficient to raise the knife off the bearings and so protect their edges. Pan Arrest—Of the self-locking, adjustable push-button type. Pans—Of aluminum, 3 }4 inches diameter. Arches—Of cold drawn nickel silver, gold plated, with a 5-inch spread. Riders—Each balance is furnished with two 10-mg riders. _ : Finish—All brass parts are heavily gold plated as a protection against all possibility of corrosion. 1848. Balance, Analytical, Troemner No. 6, as above described, without weights but with two 10 mg TCL OT ae cre Ce Ty a Ronen edd Arab eRe eer rh ore de de eo ig he ecg Arab a ted Remon Baas cen oh ot RAMS Ac 232.25 R T H UR H. T H O M A SS © -O- —Mi PAs CN: CY TROEMNER ANALYTICAL BALANCE NO. 00 1 kilo capacity 1/10th milligram sensitivity 1850—Troemner No. 00 TROEMNER ANALYTICAL BALANCE No. 00; designed to meet the requirements for a balance of large capacity with highest possible sensitivitv. Recommended especially for the preparation of stand solutions where the weighing of 1 liter of solutiun with the greatest possible precision is ele. syrean 1850. Sensitivity—1/10 milligram with full load, 7. e., a change of weight of 1 milligram on the beam deflects the poi least 134 divisions and, without load, at least 314 divisions. This is a practical working Conciiviey comosinianiinin ats adjustment may be effected in the laboratory by shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system. i beh ena As Lae in each pan a : Case f mahogany, French polished, with counterpoised front sash and with end sashes hinged to permi i i from the ends; the back door also slides up making it possible to weigh long objects SMA act the case. Outside dimensions 26 inches long, 25 inches high, 12! inches deep; inside dimensions 23 inches long, 1814 inches high, 734 inches deep. se re Central Pillar—Of double pattern, made of aluminum with brass parts gold plated; in the base are fitted vial levels of extreme ac- curacy. Beam—Of cold rolled special aluminum alloy, having great tensile strength, and maintaining its adjustment over a wide range of temperature change. It is 12 inches long, is finished in a non-corrosive black, and graduated in white divisions from 0 to 10 mg in 1/10 divisions on each side of the central knife edge. Rider Carrier—Of the double pattern, worked from either side of the case, and of simple and effective construction, which has proved free from any possibility of derangement. re P Knife Edges and Planes—Of Russian agate throughout. Release and Arrest—Of the simplest construction, the axes of the swinging arms are always coincident with the contact line of the center knife, making the release easy and effective and holding firm and secure when loading or unloading. Pan Arrest—Of the self-locking, adjustable push-button type. Pans—Of aluminum, 4} inches diameter. Arches—Of cold drawn nickel silver, gold plated, with a 5!4-inch spread. Riders—Each balance is furnished with two 10-mg riders. Finish—All brass parts are heavily gold plated as a protection against all possibility of corrosion. Balance, Analytical, Troemner No. 00, as above described, without weights but with two 10 mg riders 307.75 Note—This balance can also be supplied on special order in 2 kilos capacity with a sensitivity of 1/10 milligram, and in 5 kilos capacity with a sensitivity of 1/2 milligram, at an additional price. i 52 A R T H U_R EA: T H OF M A 8S G O° M P AON, ¥ NEWTON ANALYTICAL BALANCE NO. 210 MADE BY NEWTON BALANCE CORPORATION EXCLUSIVELY FOR ARTHUR H. THOMAS COMPANY Engraved with the names of, and guaranteed by both maker and dealer 1860—Newton No. 210 A NEWTON ANALYTICAL BALANCE No. 210; a balance of similar design to several of various makes now in wide use; an improvement in our construction, however, tends toward greater stability than in many similar balances. This feature permits a greater variation in position of the charge on the pans without in- troduction of error. Errors due to such lack of stability in balance construction cannot be remedied readily in the laboratory. This balance is of exquisite workmanship and appearance. Sensitivity—1/10 milligram with full load, i. e., a change of weight of 1 milligram on the beam deflects the pointer on the scale at least 214 divisions and without load, a change of weight of 1 milligram on the beam shows a deflection of the pointer of at least 314 divisions. This is a practical working sensitivity; some variation in this adjustment may be effected in the laboratory by shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system. Capacity—200 grams in each pan. Case—Of French polished natural mahogany with counterpoised front door and with removable sash at back. A polished black glass plate is used as a base for the balance and extends outside the case proper. Provided with drawer, two leveling screws and foot. Outside dimensions over all, 1614 inches wide, 20 inches high, 93 inches deep; inside dimensions 12}4 inches wide, 1334 inches high, 7 inches deep. Central Pillar—Of lacquered brass, with circular spirit level mounted in base. Beam—Of cold rolled aluminum, 634 inches long, graduated on each side of the central knife edge from 0 to 5 mg in 1/10-mg divi- sions, the graduations being in white on a black non-corrosive oxidized background. Rider Carrier—Slides in support attached to back of central pillar. Knife Edges and Planes—Of agate throughout and with knife edges permanently set in the beam. Release and Arrest—The beam and hangers are released by a single action arrangement, making simultaneous contact with both the central and end knife edges. When the knife edges are raised from the planes, correct alignment of the beam is auto- matically maintained. The lift is just sufficient to raise the knife edges clear of the planes and is not enough to permit injury to the knife edges should the beam be carelessly released. The lifting mechanism is provided with a long bearing surface which insures permanency of adjustment. Pan Arrest—Of self-locking, adjustable push-button type. Pans—Of dull finish aluminum, 234 inches diameter. Arches—Of hard drawn polished German silver wire, with 414-inch spread. Riders—Each balance is furnished with two 5-mg riders. 1860. Balance, Analytical, Newton No. 210, as above described, without weights but with two 5 mg riders 100.00 53 Av RT Ht UL ER H. T H O M A 5 Cc O M P A N Y NEWTON ANALYTICAL BALANCE NO. 220 MADE BY NEWTON BALANCE CORPORATION EXCLUSIVELY FOR ARTHUR H. THOMAS COMPANY Engraved with the names of, and guaranteed by both maker and dealer A.H.T. Co. PHIL 1862—Newton No. 220 NEWTON ANALYTICAL BALANCE No. 220; a new balance designed and built to meet the most ex- acting needs of the analyst. This balance is made in accordance with our own specifications, and is equal in performance and finish to any analytical balance of similar specifications as to load and sensitivity ever made. The low price is made possible by some simplification and, we believe, improvement in the arresting device and by the quantity production for which we have accepted responsibility. 1862. Sensitivity—1/20 milligram with full load, i. e., a change of weight of 1 milligram on the beam deflects the pointer cn the scale at least 5 divisions and, without load, at least 6 divisions. This is a practical working sensitivity; some variation in this adjustment may be effected in the laboratory by shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system. Capacity—200 grams in each pan. Case—Of French polished natural mahogany with counterpoised front door and with removable sash at back. A polished black giass plate is used as a base for the balance and extends outside the case proper. Provided with draw i 7 and foot. Outside dimensions over all 1714 inches wide, 20 inches high, 93g inches deep; heide deaeone ae qnehee wide, 1334 inches high, 7inches deep. Through error in engraving the case shown in above illustration appears somewhat narrower than the cases actually used. Central eet Fn ae ae level mounted in base. Beam—Of aluminum, specially cold rolled under high pressure to increase its density and homogeneity; 734 i on each side of the central knife edge from 0 to 5 mg in 1/10-mg divisions, the pradaations ee ee eee non-corrosive oxidized background. The design of this beam provides maximum rigidity under full load. Rider Carrier—Slides in support attached to back of central pillar. Knife Edges and Planes—Of agate throughout and with knife edges permanently set in the beam. Release and Arrest—The beam and hangers are released by a single action arrangement, making simultaneous contact with both the central and end knife edges. When the knife edges are raised from the planes, correct alignment of the beam is auto- matically maintained. The lift is just sufficient to raise the knife edges clear of the planes and is not enough to permit injury to the knife edges should the beam be carelessly released. The lifting mechanism is provided with a long bearing surface which insures permanency of adjustment. Pan Arrest—Of self-locking, adjustable push-button type. Pans—Of dull finish aluminum, 234 inches diameter. Arches—Of hard drawn polished German silver wire, with 4}4-inch spread. Riders—Each balance is furnished with two 5-mg riders. Balance, Analytical, Newton No. 220, as above described, without weights but with two 5 mg riders 125.00 54 A R T H U R H. T H O M A § Cc O M P A N _ Y CHRISTIAN BECKER ANALYTICAL BALANCES NO. 8-A AND NO. 15 1870 1872 " CHRISTIAN BECKER ANALYTICAL BALANCE No. 8-A; an American-made balance of high reputation and in wide use. Christian Becker balances have been made in America since 1875, and the No. 8-A balance has for years been popular in educational, industrial and Government laboratories. Sensitivity—1/20 milligram with full load, 2. e., a change of weight of 1 milligram on the beam deflects the pointer on the scale at least 5 divisions and, without load, at least 6 divisions. This is a practical working sensitivity; some variation in this adjustment may be effected in the laboratory by shifting the sliding weight on the pointer, thereby altering the center of gravity of the moving system. Capacity—200 grams in each pan. Case—Of polished mahogany, with glass sides and top and with front sliding frame counterpoised, and with a polished black plate glass base inside of the case. Outside dimensions 1614 inches long, 18% inches high, 9 inches deep; inside dimensions 13 inches long, 13 inches high, 634 inches deep. With specific gravity support and holder for weighing test tubes, with counterpoise. Beam—Of bronze of great density and tensile strength, 7 inches long with graduations in black from 0 to 5 mg in 1/10ths on both sides of the central knife edge. Knife Edges and Planes—Of agate throughout. Release and Arrest—Independent arrest for pans with automatic stop. Pans—Of polished German silver, 234 inches diameter. Arches—Of polished German silver wire, with 4-inch spread. Riders—Each balance is furnished with three 6-mg riders. 1870. Balance, Analytical, Christian Becker No. 8-A, as above described, without weights, but with three 6 mg TLC OTS oe oesehire saute SUD SEASIDE Sis acd g atsnaneea eat ASP EGS SHE IM GEE BNMD RE Le een ae el Os tae ry ne ae Tate Heaney 150.00 CHRISTIAN BECKER ANALYTICAL BALANCE No. 15. This is a high-grade analytical balance at moderate price. but which meets all ordinary needs of analytical work. Sensitivity—1/10 milligram with full load, i. e., a change of weight of 1 milligram on the beam deflects the pointer on the scal« at least 214 divisions and, without load, at least 3/4 divisions. Capacity—200 grams in each pan. : a Case—Of polished mahogany, with glass sides and top and with front sliding frame counterpoised, and with a polished black plate glass base inside of the case. Outside dimensions 16 !4 inches long, 18!4 inches high, 9 inches deep; inside dimensions 13 inches long, 13 inches high, 634 inches deep. : Beam—Of aluminum, oxidized black, 6 inches long, with white graduations from 0 to 5 mg in 1/10ths on both sides of the central knife edge. Knife Edges and Planes—Of agate throughout. : ; Release and Arrest—Independent arrest for pans with automatic stop. Pans— Of polished German silver, 214 inches diameter. Arches—Of polished German silver wire, with 4-inch spread. Riders—Each balance is furnished with three 5-mg riders. 1872. Balance, Analytical, Christian Becker No. 15, as above described, without weights, but with three 5 mg TL OLS cena cooess cot ec vrnt B ace ctiane ake Seno tien date one Seca a a bete innit Rpt Ld fee ay Se RelA ent ge 110.00 We maintain classified information and prices of many items required for laboratory work and not listed in this catalogue. This information is always available to our patrons upon request. Where it seems more desirable to purchase directly from the original source rather than through our medium, such recommendation is promptly offered. ae 55 A RK YF HU R H. T H O M A _S Cr Or ME" PEA Ne: CHRISTIAN BECKER CHAINOMATIC ANALYTICAL BALANCES NO. 8-A AND NO. 15 1880 CHRISTIAN BECKER CHAINOMATIC ANALYTICAL BALANCES No. 8-A AND No. 15 are of the same general construction as the corresponding No. 8-A and No. 15 balances as far as knife edges, bearings, ete., are concerned, with the exception that there is no rider and consequently no graduations on the beam. One end of the weighing chain is hung from an arm of the scale beam, and the other end from a slide-block which is moved up and down on a vertical graduated scale. As this block is raised, more of the weight of the chain is taken from the beam and hangs from the slide-block which forms a stationary support for holding the ee part of the chain. As the slide is lowered a greater proportion of the weight of the chain is transferred to the beam. To read the effective weight of the chain the vertical guide is provided with graduations according to any desired denominations representing, for instance, milligrams, so that when the zero mark on the slide regis- ters with any of these graduations the weight of the object being weighed may be directly read off. For finer readings this construction lends itself readily to the application of the vernier. For this purpose both the slide- block as well as the vertical scale are graduated, their respective graduations differing by one unit, that is to say, for 10 graduations on the guide there will be 9 on the slide; consequently each of the vernier divisions is read as 1/10 of a milligram. The links of the gold-filled chain are practically all uniform in weight, hence the gradu- ations are uniformly spaced. A thumb-wheel is provided at the right-hand of the base of the case. This manipulates the spiral drive— the feature which has made this invention practical. By turning the thumb-wheel the slide-block is raised or lowered and remains in any position in which it is left. After all the necessary large weights up to 50 milligrams are placed on the pan, the weighing from 50 milligrams to 1/10 of a milligram can be concluded without opening the balance or using the arrest, eliminating the necessity of reading and replacing all small weights or the handling of a rider with a consequent saving of time. 1880. Balance, Analytical, Christian Becker Chainomatic No. 8-A; this is the regular No. 8-A Balance as described on preceding page, but equipped with chain (detailed description of which is given above) giving direct rapid readings without riders or small weights. Without weights.... 190.00 1882. Balance, Analytical, Christian Becker Chainomatic No. 15, exactly same as the regular No. 15, but with chain, giving direct rapid readings without riders or small weights. Without weights..... 150.00 The merchandise listed in this catalogue originates in some 1200 different establishments. The selection is based upon thirty years of experience in the supply of apparatus and reagents to chemical, metallurgical and biological laboratories and has been made with painstaking care. 56 A R T H U R H. T H O M A S Cc O M P A N _ Y mm AAA TT Morn i) : Troemner Assay Balance No. 30, designed to meet the demand for a low-priced, short-arm balance, with a sensitivity of 1/100 milligram and of quick action. It requires but 13 seconds for one complete oscillation. Sensitivity—1/100 milligram. Case—Of old, well-seasoned mahogany, French polished, with glass sides and top and counterpoised sliding front door. With polished black plate glass base inside of the case and with reading glass for the ivory index. Outside dimensions 18 inches long, 18 inches high, 914 inches deep. Beam—Of hard rolled aluminum alloy of great tensile strength and oxidized black, graduated in white divisions on both sides of the central knife edge into 50 divisions. The beam is unobstructed on top so that the rider can be placed at any division on the beam from 0 at the center to the last division on the beam, which is directly over the end knife edge and represents the full weight of the rider used. With a one milligram rider on one-half divisions, or a one-half milligram rider on the full divisions, the balance shows 1/100 milligram for each division on the ivory index. Rider Carrier—Of single double-hook pattern, operated from the right hand side of the case, giving full, clear sweep across beam. The rider, either single or double, can be placed at any division on the beam. Knife Edges and Planes—Of Russian agate, accurately ground. Finish—All brass parts are covered with an impervious lacquer. Riders—Each balance is furnished with two 1-mg riders. 1890. Balance, Assay, Troemner No. 30, as above described, without weights but with two 1 mg riders 198.00 1892. Balance, Assay, Pocket. Improved form with eccentric lift for beam. Size when closed is 6 x 23 x 1} inches. Capacity, 10 grams; _sensitivity, + mg. Complete with set of weights. A half assay ton weight is usually supplied in place of the 10-gram piece..........................00. 13.50 cea 1894 = 1894. Balance, Laboratory, recommended for a great variety of laboratory work other than analytical. With , steel knife edges and planes, in polished mahogany case with glass sides and top, counterpoised, sliding front door, leveling screws and spirit level. Capacity, 100 grams; sensitivity, 3 milli- : , 75 mm diameter, and nickel-plated beam 8 inches long. Without weights. ... 30.00 1895 dice hut Tike agate knife edges and planes of steel. Recommended for use in the tropics. Without yA SWESD se deph mieos aera eA TIA I NOP Dre teins NPM EAS EN TVS NO EN BES 36.00 i _ This balance is made entirely of aluminum alloy, and will, therefore, be found to Meee Peete an ceasnylly resist the corrosive action of acid fumes than do balances made of brass, etc. The knife bearings are of agate and the beam is divided to facilitate the use of a rider. Capacity: Beatin: toa seen Nere eta ne CREE era ST ee EY ete ny 250 Sensitivity; milligrams... .cycqnes43 eet eee tee RE eT aaa ae Bach “Without weigntssys cen ease eun eee A Pe Aine eee Gets 32.40 37.80 A: RO IT Hy Uo OR aan T HO M AS Gc © M PA N Y pombe nas ATATUTTOTANTY = O ge E oh—AOA TO TTOATIT : = = = = 1900 1901 1902 1900. Balance, Prescription, of brass with nickel-plated pans 3 inches in diameter. Beam 9 inches long with adjusting screws. Sensitivity 2 mg, without weights. ............. 6. cece eee eee eee eee 12.00 1901. Balance, Prescription, of brass, on wooden base, with drawer. Beam 6 inches long, pans 3 inches diameter. Without adjusting screws at end of beam. A useful balance at a low price, without weights.. 9.00 1902. Balance, Staudinger School, with agate knife edges and planes, improved beam and hanger arresting device, on heavy wooden base with leveling screws; with removable pans. Recommended as the most accurate and satisfactory school laboratory balance, of its type. Capacity 100 grams, sensi- tivity 1 milligram; without welghts:....... 229. tse h. deew we en Ae ee ee 25.00 1903. Balance, Lecture Table. A short beam balance with arrestinz device for both beam and hangers, brush pan stops and removable scale pans. A very convenient balance for weighing large flasks and other containers either on the lecture or laboratory table. The beam is of aluminum and the column of iron, heavily black enameled. Both the central and end knife edges are adjustable, and the bal- ance is mounted on a substantial wooden base with spirit level and leveling screws. This balance may be used up to twice the capacity indicated. Capacity, 3 kilos; sensitivity under full load, 20mg without -welghts sci acessories dyoicee bp sennsd ae hee lee Seeeaie tea logan ones a antenes eee te aes 80.00 BALANCE, LECTURE TABLE, capacity 5 kilos, sensitivity 10 milligrams; a large capacity balance of un- usual sensitivity and rugged construction, designed primarily for lecture table experiments but which, because of its capacity and sensitivity, has found no little application to other laboratory work where large loads are to be weighed, particularly in flasks or containers, with an accuracy not possible in the ordinary balance of this type. The beam is divided in 100 equal divisions with zero at the left so that a 500 mg rider can be used with a value of 1000 mg at the right-hand end of the beam, thus giving each division a value of 10 mg. This arrangement prac- tically obviates the use of fractional weights and greatly increases rapid and con- (Continued on following page) 58 A N Y OQ M P UR H T H OF M A 5S Cc A R T H z vermin rev ererenepye erp mre RT NTO eapeennrengy ery x a peerree yA ten ( “ill i ig oe ee aan i ai TMM Bale I t I oniinue: rom receding page) alance, ued fi Dp / ance ecture able (C niin tainer carriers, vy knife edges of agate. Con ee ee Fact ae penta io beam, hangers and pans. 3 . The beam is 0 rons and an arresting devic venient operation. djustment of sensitivity, Baas . justm' sliding weight for a 904 Balance, Lecture Table, as above described, capacity 5 kilos, sensitivity illi d on highly j itivi 0 milligrams, mounte olished mahogany base wi h a ng ec S a tee aaa weights............ Ley : ‘ hed gan ee Ahoean : ae Syithout WOIBIES: fi. Aan wetecneatien tees 235.00 it lis with glass case eaunted in mahogany fr , i but with g 1905. ditto, aos nd for a more sensi- alance aboratory, for students i meet the demand fo: 2 : 1907 B Lal tud ’ and lecture table use. Deeuee to ik be : vided ‘ i F ng we "3 an xed scale Grade ed to 10 grams in 1/10-gram divis ons. re | | aring 3 a e ue a pans are 0 = d 5 oof = ee enameled steel, 140 ae Pate Tota ° 5 +dj 1 oe : ite ¢ 10 n be ae 0 ses 17 nches Can 2 idle: sensitivity, 20 mers. me eee pee ane 1 i Ree Cae One eet, 2 h at ane ‘but without weights sewer y' 0.00 i i ick arrestment, : ing device for quick ne ’ and lecture table use. ae soe Bae ae Diels: sensitivity, tory, for students’ an ble shelf for specific gravity i i 1908. Balance, Labora f steel, and an te of open construction, fe, end devising 2 es ai Io a bearings es with full load. Wit 10 grams by 1/10-gram divisio re ee bea vindicate - oa on ae With leveling screws, p pean inum, 140 mm : Pans are of alumi sates np 25.00 but without weights..............-- Ay ORS SF Uno WU &R H. EL 1910 1911 BALANCES, PULP, New Standardized Model. The column is made of a single piece of aluminum, com- bining lightness and rigidity, and reducing the possibility of the balance getting out of order under severe working conditions as compared with the old construction of cylindrical brass column. The planes are of agate with steel knife edges. The pans are nickel plated and removable. The lifting mechanism for the beam is the standard eccentric movement used on modern Analytical Balances. Adjustment screws for equilibrium of beam are supplied as are also spirit level and leveling screws on the base. The Balances are mounted on French polished mahogany base with drawer, and in French polished mahogany and glass case with front, counterpoised sliding door. These Balances are used for a variety of laboratory purposes, such as weighing prescriptions, sugar, pulp, etc., and will give satisfactory and accurate results in other work requiring an even beam, knife-edge Balance. The 300-gram size in glass case is usually known as the ‘Sugar Balance,’ because of its wide use in sugar labora- tories for weighing out of normal weights of sugar for the Saccharimeter, for which purpose an Analytical Balance should not be used because of the time required. 1910. Balances, Pulp, New Standardized Model, as above described, on mahogany base with drawer. With- out weights. Capacitys Qramsicnicrs nites tock kgs ae ea eens et ees 150 300 600 1500 Sensitivity; Merve eae anes a ae and ies APG 2 5 5 10 Diameter of pans,mm...................0.0.0005- 82 102 127 152 Length of beam, mm......................0..0200. 178 235 267 286 BMG rs ke ak ices oar a cea ed fect me ee po sea Gees 21.60 27.00 36.00 45.00 1911. ditto, but in mahogany and glass case with front, counterpoised glass door. Without weights. Capacity; Prams occ ns ee in ence wee nice heed aloe ee 150 300 600 1500 Sensi tivity eM gt 0) ete aeraegs 2G Vind 4s eens aww Gere che ee 1 2 5 10 Diameter of pans,mm.................. 00.0.0 0005 82 102 127 152 Length of beam, mm.........................00200. 178 235 267 286 a Chics ee hee ae -0 oes Be se GEOR e are A 34.20 45.00 54.00 72.00 1914. Balance, Tropical Sugar. This is the 300-gram capacity Balance No. 1910, but with agate knife edges as well as agate planes. While the use of the agate knife edges requires careful use to avoid chip- ping of the edge, the difficulty in the moist atmosphere of tropical countries because of the rusting and corroding of the steel knife edges makes a Balance with both agate knife edges and planes seem necessary. Capacity, 300 grams; sensitivity, 5 mgr.; diameter of pans, 102 mm; length of beam, 235mm. Mounted on French polished mahogany base with drawer. Without weights 31.50 1915. ditto, but with 2 mgr. sensitivity, and mounted in French polished mahogany and glass case with front counterpoised glass door. Without weights............ 0.0.0... cece cece eee eee 49.50 1918. Balance, Harvard Trip, with 6 inch square porcelain plates. Capacity 1 kilo, beam graduated up to 5 grams in 1/10 gram. Without weights..........00000 0002000 9.00 1919. ditto, but with agate bearings. Without weights.................. 0000000 12.75 1920. Porcelain Plate, only, 6 inches square, for Harvard Trip Balances, sold only in pairs, Per pair... .. 1.20 1922. Balance, Robervahl, with heavy brass pans, upright indicator and graduated ivory index scale. Capacity, IDS ice saison tc plant me seats. 1 Sdeon tices aur tiaens camaunats 1 2 5 Sensitivity, nals $< oc aes acasucs sacar wa eacutue: Gur iace se elec pudleGuecoand wae 10 15 20 FE a Cn eset cers Syst emery oe de ees Rico ap Tey eid en eh “10.80 12.00 14.40 1923. 1924. 1925. 1930. 1931. 1932. 1933. Balance, Counter, in ebony box with marble top and heavily nickel-plated pans. Diameter-of- pans;inches.:-. sae) bckee seek dered hs hia aes 7 8 9 GCapacitys bse. alts. ci o7 saan uth SAmlpie Oe REIS Romtrels tot wate ne Mes e 5 8 10 Bach-withoutoweights, adic, oss irer a0 exes Me eral payee eR! = 21.60 25.00 28.35 Balance, Trip. A very substantial and reliable scale, with one heavy, brass pan which is removable. Diameter of. pans; INCHES so. onan ke salam beans rau auan) balarwaebeh ua ae 9 12 Ga pacity Usha: sa rsceds te nenrscawe. ead so nays ort eam tanh vse reece Perna 2 6 10 Each-without weights <.cs.c2 saree atic eere se ne ek ays A 14.40 16.20 17.50 Balance, Prescription. Very convenient in laboratory and pharmaceutical work. With nickel-plated pans 6 inches diameter, capacity 310 grams in each pan, sensitivity 1/10 gram. Price includes set of brass weights from 200 grams to 1/10 gram fitted in base......................... 15.30 Balance, Moisture, for determining the percentage of moisture in ores, etc. Beam is divided on the top into ounces and on the bottom into percentage of 100 to 0. Including a set of iron weights from D lbs: tO OF; AVOIGUPOIS eax ae nia ced, cc Siren PS metas sealan Re Ne Kanaan eaten eae 3 16.20 Balance, Solution. With two weighing beams and sliding poises, one divided into 100 parts, each repre- senting 1 gram, the other into 10 parts, each representing 100 grams. A bar with a sliding poise is placed under the weighing beams to balance the empty bottle or container, which is quickly done by sliding the poise along the bar. Total capacity 20 kilos, sensitivity 1 gram. Complete WET SELIG WELD US eens 2 ey cab ita aoc tom clause sneaniiagir snestha tate milage aye dau aleaau Nanaueniyn aaeten Vo Mawes aos 67.50 Balance, New Dispensing. Very convenient for rough prescription or laboratory weighing, with pans 32 inches diameter, heavily nickel plated. Upper edge of beam is divided in 120 one-grain divisions and lower edge to eight grams in 1/10-gram divisions. Capacity 110 grams. Including set of brass weights from 50 grams to 1 cgm, fitted into base............... 6.00. e eee eee 13.50 Balance, Extra Large Dispensing, similar in appearance to No. 1932, but of larger capacity. With steel bearings and with side beam graduated from 1/10 gram to 5 grams in 1/10-gram divisions. Capa- city 210 grams, with a sensitivity of 1/10 gram. Pans are 5 inches in diameter. With set of brass metric weights 100, 50, 20, 20, 10 and 5 grams..................... 000000005. ... 16.20 61 1936. 1937. 1938. 1940. 1941. Balance, Torsion, with glass and metal case and cover, and slide beam with rider carrier operating from outside. Capacity 120 grams in each pan, with beam reading to 500 milligrams by 5 milligrams. Pans are 3 inches in diameter; sensitivity 2 milligrams................ 000000000. cece ace 60.00 Balance, Torsion, with mechanism entirely closed in glass and metal case, with nickel-plated base, nickel- plated brass pans 9 inches in diameter. Capacity 4.5 kilos in each pan. Beam reads to 100 grams by 1 gram, sensitivity 1/5 gram. Rider on beam is manipulated from outside the case. With slide beam inside the case controlled by weight moved from the outside...................... 60.00 Balance, Torsion, with arresting device and nickel-plated pans. Sensitivity 1/3 gram. Capacity: inveachspan’. Kiloss 22sec ce aeatin Weta een Sean gee ean Mea a ee TO 2 43 Diameter or pansy inches... 2:5 34 5 aoe acs sas ac ces ess See eo By BN 6 9° Lengthof- beam inches: <2) 10 eyes ae ete ee eget ete tale Siebel eeloes 9 12 Slidesbeams-Oramee te conn cca weaeee rs canst aneripac ahd tes nhiaicesie ns Dees zua ie mute, 100 500 Slideibeam/ divisions; OramMsinc cues ie. e May cots ticle ee Ricks dee id deeghncenerg ee weit ae 1 5 BAC Hisense 8 eae eee nee ohe eee sete ime el trainer ee eens tay A Site mae ae 28.00 31.00 Balance, Torsion, with tare weight. Bottles, dishes or other containers can be tared by sliding tare weight on upper beam, facilitating weighing and avoiding errors. With nickel-plated brass pans, and with arresting device. Capacity-inseach pan, Ads. .3 2 asses eis seaikiockloaidan Nani vuhett tw arn aed ore eeee an 2 4i Sensitivity; ChamMsy «ie aciacd. desde dha Ales Dantican din ant -qdoschaiea tet aeda a aud Seren pace 1/8 1/4” Diameter of pans, inches................. 000.0000 eens EEO eee ee 6 9 ‘Bength of beam;nchese rs. cox guie ssc hie eae oe Greet ales ae atone oh atone 9 12 Slide: beat OTAamS sien ses, wieeuas Sees te Fs Saeed Fh Momeni kde saee etend 100 500 Slide: beam: GivislOns; @TamS. 6:55 2 45226h 2-2 & asians ee Gok ey SU ee ea atin namin cn Ses 1 5 BNA Ciena 9 cece ieee cece Sones beet ey tics Bek Mant a tah eae hte ne hell 32.00 35.00 Balance, Torsion, as recommended for soil analysis and as used in the U. S. Department of Agriculture. With slide beam divided in 10 grams by 1/10 gram. Capacity 1 kilo in each pan, sensitivity 1/15 gram. With 6 inch diameter porcelain plates, high poise, indicator and arrest............. 35.00 62 1944 1942. Balance, Torsion, Moisture. Enclosed in white enameled case with leveling screws and index; four beams with sliding weights; two upper beams graduated for tare or counterpoise; lower beams graduated to 10% by 1/10, and 20% by 2/10, so that from 1/10 of 1% to 30% of moisture in 10-gram samples can be determined without calculation. Especially valuable for moisture in butter. The pans are brass, nickel plated, 3 inches diameter. Capacity 120 grams in each pan, sensitivity 13 milligrams. Dimensions 10 by 54 by 93 inches over all.................... 35.00 1944. Balance, Solution, Metric, for rapidly making accurate reagents or other kind of composite solutions. With two movable brass pans. With slide beam in front, undivided, for balancing the bottle_or containers. Price includes weights of solid brass. Capacity inceach” pany kalos's 554.45 arc neste aikeeh a Sian bce ae Ma tas abet ett 1 5 Diameter.ot pans; 1m Ch Os 197 c.0< c3 A te person tietsnnres wesern se tebe e Nel ease anes eiele ge 5k 9 ara le Pane uh anh alr egg oaial faethe oem a icracepa nein aie Oca aR iw en A nen nic Ca 36.00 42.00 1948 1950 1954 a 1 e, Jolly Spiral Spring, with new patent reading scale. The inner tube can be adjusted up or down ee sage ent the milled head and is graduated in millimeters with vernier reading to 1/10 mm. This balance has been found very convenient in many industrial laboratories, such as in rubber works, for taking specific gravities........... 02.0. cece eens 50.00 iB , Specific Gravity, Westphal. For the determination of the specific gravity of liquids up to the ey Dee decimal place. With jar, riders and Reimann Plummet, complete................. 30.00 1951. Reimann’s Plummet, only, for use with ADOVE:DAlANCOsesteeet cerca ee hain ty WanerymAa Las rane eet eeY & 6.00 1952. Set of Riders, for use with above TB etl tn CO cs Sess eee pee tet see ic no escola eG acces 40,00 Su aout es 3.00 4390. Jar, 150 x 25 mm, for use with above balance............- 0.6.6 cece 18 , Specific Gravity, Precision, for both solids and liquids. This is a superior balance reading ce le to the fourth decimal place. With plummet for liquids, pan for solids, special double compartment jar as shown in illustration and thermometer for convenient hanging on the side of CHE FALE css ny Gases Pere tok Gah nated see EN ee Eau Genre ee gis nara inne eS 37.50 1955. Plummet, only, for above...... 606 eens 2.00 1956. Set of Riders, only, for above... . 2.2... 6.6 eens 1.50 1957. Thermometer, only, for above... 2... 6-6. e eee eect treet ee oy 1958. Jar, only, for above... 0.0... cee tenner ete teen tenes 2: ’ CIFIC GRAVITY CHAINOMATIC BALANCE FOR LIQUIDS, with graduated scale giv- ing see Deaac gravity to the third or fourth decimal place without the use of riders or weights. Determinations are quickly and accurately made by adding weight to the beam by means of the chain. The plum- met is immersed in the liquid to be tested. The rotation of the handle placed at the right of base manipulates a spiral drive which raises or lowers the chain, one end of which is hung free from the beam and the other end from a slide block which is moved up and down on a vertical graduated scale. This scale is provided with vernier and 63 1960 BECKER SPECIFIC GRAVITY CHAINOMATIC BALANCE—Continued. is graduated to give direct readings in specific gravity with an accuracy equal to a high-grade analytical balance. The plummet displaces exactly 2 grams of distilled water at 15° C, and the enclosed thermometer ranges to 30° C. The case is of special design with glass front and adjustable sides which, while reducing the air disturbances to a minimum, insure freedom in operating the balance. 1960. 1961. 1962. 1963. 1964. 1965. 1966. 1970. Balance, Becker Specific Gravity Chainomatic No. 103, as described on page 63, ranging to 3.500, to third decimaliplace:\ With case veut ote Set cit: Atanas ty kinastitare Ngan Atk ele Oe 100.00 dittoybut.withouticasee ce oul sk cogent SL tne on eR ie ie aera coit tole Mes 85.00 Balance, Becker Specific Gravity Chainomatic No. 100, ranging to 2.000, to fourth decimal place. WAL NCASC ren ctr Aon eto Wears hie tha rota toctta we Mek eee Eph ta Pata cane Syne Sa erent ee aot 100.00 1966 1970 Balance, Triple Beam. The three beams”are placed in the same horizontal plane, thus conforming to scientific principles involved, which is not true of other styles of triple beam balances. Weighings are obtained by movement of the riders along the beams. These riders are easily handled and quickly placed ‘n the notches, but cannot be removed from the beams. An adjustable support is provided for a jar or other receptacle for experiments in specific gravity. Provided with a stable base neatly japanned, and with sensitive spirit level and leveling screw. Balance neatly finished in nickel plate and japan. Capacity of middle beam 100 grams by 10-gram divisions: back beam 10 grams by 1-gram divisions; front beam 100 centigrams by 1-centigram divisions. Total capacity 111 grams; sensitivity with or without full load, guaranteed to 1 centigram. Actual tests, however, give a sensitivity of from 4 to 8 milligrams. Diameter of pan 9.5 cm; width of bow 10.5 cm; height of bow 22 cm. Features easily recognized are: rapid weighing, constant sensitivity, accuracy, freedom from loss of weights, no interference or breaking of weights..................... 26.50 Balances, Hand, with polished brass beam, steel knife edge and horn pans suspended by cords. Then oth: of earns AMIN. jie csdatecs suis Seceieestuaratp ce Seer dane, « waaependucnss sania peters mllateintan 150 200 Diameter of pansy minis 6 205k oa wed oo enc eas tye ties es eeemsctie deen cede test : 60 80 Ba Cleo ates en agian act abies uaa aes gaa omen eten coe em eects ne Beas A Ta 2.00 2.75 Ay RT EP Ur YR: H. T H O M A § Cc OQ M P A N Y ANALYTICAL WEIGHTS 1972 1986 : ANALYTICAL WEIGHTS, A. H. T. Co. Double Checked. As suitable for all ordinary analytical weigh- ings, we offer this series of weights made under our direction and in accordance with our specifications. The weights are all checked upon completion, and again after lapse of a considerable time in order to detect the small changes in value which sometimes occur. No weights are put into our stock with errors greater than those given in the tolerance table, but chemists are reminded that slight changes in value occur both while the weights are in stock and after they are put into laboratory use. The tolerance to within which these weights are adjusted are as follows: Denomination Tolerance Denomination Tolerance Denomination Tolerance Denomination Tolerance 100 grams = 0.5 mg. 5 grams = 0.15 mg. 200 mg. + 0.05 mg. 10 mg. + 0.03 mg. 50 0.3 * 2k + 0.15 “ 100 “ = 0.05 “ Doe + 0.03 “ 20 * HQ22ie ce a ee + 0.10 “ 50“ + 0.04 “ Qian’ + 0.02 “ 10S =02 500 mg. + 0.10 “ 20 “ + 0.04 “ Tes + 0.02 “ The weights are supplied in a velvet-lined, polished mahogany box, with fractionals and riders under plate glass cover, and with ivory-tipped forceps. The fractionals from 1 to 20 mg are of aluminum, and from 50 to 500 mg are of palladium and gold alloy or platinum, as may be the more readily obtainable. The fractional pieces have one edge turned in a vertical position for convenience in handling with forceps. One each 5 and 10 mg riders are furnished with each set. 1972. Balance Weights, Analytical, A. H. T. Co., Double Checked, as above described, with gram pieces heavily gold plated. Sets from 1 mg to grams.................... 20 50 100 200 Per Sette ia sueh ed Satta ang eres ois 21.75 23.50 26.75 33.75 1974. ditto, but with gram pieces carefully lacquered instead of gold plated. Sets from 1 mg to grams.................... 20 50 100 200 ROE (SCbies a sei seatists ous laters doo tana Rene ee dete eee etoe 19.25 20.50 22.75 29.25 1976. Balance Weights, Analytical, Imported. These sets are identical in general appearance and tolerances to those immediately preceding. The gram pieces are heavily gold plated and the fractionals are of pure nickel and aluminum. Under prevailing conditions of foreign exchange, these sets are relatively very low in price. Sets irom: Lame CoveTams ie kon ire ch eieee acs ey na eens yee een nel eh ue toad tens 50 100 POR SOU eee es hic en cei ba ecepeh Sma tas oetap SAGA gg tig ema ra saaiyy Ci ach cise many aoseh sis cuese ema ses 13.00 16.25 1980. Balance Weights, Analytical, Oertling, N. P. L. Certified. These weights are similar in appearance to our No. 1972, except that the gram pieces are of heavily polished brass, for which greater durability is claimed than gold plated. The larger fractionals are of gold and the smaller fractionals of aluminum. Three riders are furnished with each set and the fractionals are in separate compartments under a plate glass cover. Each set is furnished with certificate of the National Physical Laboratory, Teddington, London, on which is stated the actual value of each piece to within + 0.0001 gram for weights of one gram and upwards, and + 0.00001 gram for the fractional weights. Setstfrom@el me tor grams sco, eto ensuites oe cannes Ganle haNains Gottenles tl saath ae esas 50 100 Grete rscersccay seas es eee genes eels vp ae ER gL Ae Ola gn eden oS 49.00 53.50 1984. Balance Weights, Analytical, Troemner, in velvet-lined, polished mahogany box, with fractionals and riders under plate glass cover, and with ivory-tipped forceps. Gram pieces are heavily gold plated, and fractionals from 1 to 20 mg are of aluminum, and from 50 to 500 mg of palladium and gold alloy, or platinum, with three 10 mg riders. The fractional pieces have one entire edge turned in a vertical position for convenience in handling with forceps. Sots from: Um tOr rams «tac ce a saceoa see he anerneeen hele hae, waitin doa detect dnohn, Sas outs 50 100 PER SEL Spies seca ead ett as tes Uh te head op rath Sind He sia ay node Moret esate as zaps 45.50 50.40 1985. ditto, with Bureau of Standards certificate for Class S...............0--20000- 54.65 60.00 1986. Balance Weights, Analytical, Troemner, in mahogany block with removable cover. Gram pieces are carefully lacquered, and fractionals are exactly same as supplied with No. 1984. With ivory-tipped forceps. Sets from: l-me-to eramsiey Sse aaenes ee een ae ae 50 100 200 PGT. SOUS aan ee eT a act ease nce Va Lectanr 39.00 40.00 43.25 1987. ditto, with Bureau of Standards certificate for Class S.............. 48.35 50.10 65 A OR. 7 Ve oO CR. Fl ot ET Oe IM Ac eS Gc © M PAN ¥ snc) a] a rT W i a a fo J ea 2000 2004, 2005 2010, 2011 2000. Balance Weights, Fractionals, in wooden compartment block with hinged lid. The pieces from 1 to 20 mg are of aluminum, and from 50 to 500 mg of palladium and gold alloy, or platinum. Each set contains two pieces each of the 1 mg, 2 mg, 10 mg and 100 mg weights. Sets from 1 mg to DO OTN OF Sn ale rnin piace Strand tacarniwe ot hn Sem Shek Teh one eere a hiaey 1a, edie ore thie nit a eek ear oh re 15.00 2001. Balance Weights, Fractionals, separate pieces only of aluminum. SIZE IMO ac oh ek Perse hoe NA Plot A hier ty ot teeta Bite Soin nhnind irre 1 2 5 10 20 aC nce cae Ba eek ta as he ea saln ON eer toe iced -20 -20 .20 .20 .20 2002. Balance Weights, Fractionals, separate pieces only of palladium and gold alloy, or platinum. SIZES INO or carta tier Daten er ieee mare UR fi epth oe cas Ch Ganin feet ota 50 100 200 500 IESG Hs ae capt uit osu eeu Cada tiated ok emena Rae el A ele -65 1.00 2.00 5.00 2004. Balance Weights, separate gram pieces only, of brass, gold plated. Size, grams.......... eel 5 10 20 50 100 ACH tia ei tact eles .80 90 1.00 1.30 1.60 2.10 2.90 2005. ditto, but carefully lacquered instead of oe plated. Size, OPRAMS 6 416k soca ow 1 5 10 20 50 100 a Cleats or sie aan ttere 50 60 -75 -90 1.00 1.20 1.90 2010. Riders, of aluminum, carefully adjusted. Size, milligrams . Sec Bele 1 2 5 6 10 12 Each: cosck hot oae -20 -20 -20 -20 .20 .20 .20 2011. Riders, of platinum, carefully adjusted. Sigex milligrams. se caewe ven ce good ie Meee a reste eee 5 6 10 12 Baie en aren at Se Ai sin tia Mae, St eee Ry woe EOLA ae han ee -40 -40 -40 -40 Note—In ordering Riders, please specify make‘and_type of balance on which they are to be used and they will be sent of proper shape to fit beam without bending. 2020 2021 STUDENTS’ ANALYTICAL WEIGHTS These weights are guaranteed to be within the tolerances given below, which are deemed suitable for the purpose intended. Where they are to be used in precise quantitative analysis, it is recommended that they be checked in the laboratory against a certified set of weights. Where a number of sets are provided for,students’ use, the checking may be conveniently done against a few single certified pieces. Denomination Tolerance Denomination Tolerance 100 grams + 2.5 mg. 500 mg. + 0.25 mg. 50 +15 “ 200 +0.25 “ 20: ** +10 “ 100 “ +025 “ 10: +0.75 “ 50“ +015 “ 5: +0.75 “ 20“ +015 “ Dee ESS +0.50 “ LO: <* +0.10 “ Lior +050 “ 5 +0.10 “ 22a +05 “ ees +05 “ 2020. Balance Weights, Analytical, designed especially for use with the Troemner No. 35 Balance. The block is of a size to be conveniently stored in front of the ivory scale, but must be removed from this position when the balance is in use. The single pieces are of brass, carefully lacquered, and the fractionals are of aluminum. Setsrirom: lsmg tocorams cua vnciioni es tate Ie. Ss eee 20 50 100 Cr By oo 4 ino ea athels os wee eda ee at a Aen haa orn Pu era ea 7.25 8.75 10.50 2021. Balance Weights, Analytical, as above, in case with velvet-lined lid. Set from JomgCov grams v6. eve tas ee ee es AS as 20 50 100 200 PERSO bee becky We sueene ces bsg ahaa eres coat chistes ciety essa 9.00 10.25 12.50 17.50 A UR Tn oR H. TE O° Me Ac :S C O M P A N Y 2029 2031 2034 SPECIAL WEIGHTS 2028. Balance Weights, Normal Sugar, Cylindrical, brass, gold plated, for use in making solutions based on the Mohr sugar ce. RIZE seaman antares Wi eae arc paceaaiesner eer Nea oneM id ore Romsey ean CT Onde Half Normal Normal Weight; cramsi sit acd yosocn Wa Wire evias x Gate nied nea Mantua len sa toenrte henetreneraletie 13.024 26.048 a CH eee ie eee a eel yh crn eT NMA CU eur i Gee etl ye ate RAT me Ct 1.50 2.00 2029. ditto, set of two, as listed above, i.e., half normal and normal, in hardwood block with hinged lid.... 5.25 2030. Balance Weights, Normal Sugar, Rectangular, of brass, for use in making solutions based on the metric or true milliliter. WGI GIG PAIS s my stiercat cine dosti a wine Act US enact eran rane at bac a oi AE eet Me Set RS Ne 13 26 Ba Ina eh rate Oxon 8 ath peek oe ie MP teat Mies Mn AR ant bei wet Ries ERO rea s hotlt eras atsAl Cuore 2.00 2.50 2031. ditto, set of two, as listed above, 7. e., 13 and 26 grams, in wooden case with lid............... 6.50 2032. Weights, Factor, of lacquered brass with the exception of the 1/10 silicon, which is of platinum. As used in iron and steel analysis. SUVleias aint aie Ran Carbon 3 Carbon } Silicon Phosphorus 1/10 Silicon Weight, grams............. 2.7273 1.3636 1.1755 1.63 0.4702 Hache5.8. oc Se. a thas OO be 1.75 1.75 1.75 1.75 8.00 2034. Balance Weights, Assay Ton, Troemner, of brass, polished and lacquered, with screw knobs, in mahogany block with forceps. The Assay Ton Weight is (according to Prof. C. F. Chandler, who introduced it) of the value of 29.1666 grams; it, therefore, contains as many milligrams as there are Troy ounces in an Avoirdupois ton (2000 lbs.). If, therefore, one A. T. of ore assays 1 mg, the ore con- tains 1 Troy ounce to the ton. Setss 1/20: eA COs ee cote leds ak ate Ste ek ete ty a a ned he cae eels a 1A. T. 4A. T. POLS OU cen rid artis es cet aaa ct rhe eT ESO AUS SLED Co EE Raa Ab et eee MS 10.00 13.00 2036. Weights, Assay or Button, accurate within the tolerance + 0.01 milligram. Set from 1 gram to 0.1 gram, in ebony compartment block with hinged lid. Set consists of platinum pieces 1 gram, 500, 200, 100 and 50 milligram; aluminum pieces 20, 10, 5, 2 and 1 milligram; pieces of aluminum wire 0.5, 0.2, and 0.1 milligram. Duplicates are supplied of the 100, 10, 2 and 0.2 milligram pieces. 45.00 AAT .CO, 2050 2044 2046 WEIGHTS OF MEDIUM ACCURACY 2044. Balance Weights. Of solid brass down to 1 gram inclusive; 500 milligram to 10 milligram pieces inclusive ay are Be aluminum or nickel. In block with hinged lidand compartment for fractionals and pair of steel forceps. Sets, 10 milligrams to grams............... 20 50 100 200 500 1000 Per Seb. hb Aly es 3.75 4.50 5.50 7.00 9.00 12.00 2046. Balance Weights. Pieces down to 1 gram inclusive of brass, while the fractionals from 500 milligrams to 10 milligrams are of aluminum. In open wood block with covered compartment for the small pieces. Sets, 10 milligrams to grams....... 20 50 100 200 500 1000 2000 Per Seb eka dole Ao eee ei Sa 2.25 2.50 3.00 5.00 7.00 10.00 15.00 Weights, single pieces of brass, as supplied with sets No. 2044 and 2046. a Bete ‘ E ‘ c ... 2000 1000 500 200 100 50 20 10 5 2 1 Beh. eeore kage 4.50 3.75 2.00 1.25 1.00 60 50 .40 35 35 .30 2050. Balance Weights, single fractional pieces of aluminum. The 10 to 500 milligram pieces are identical with lied in sets No. 2046. pr | fine ae Ce ee 500 200 100 50 2 10 5 2 1 Beles re tenia eee ees Ws ie A ee ae ee 67 2052. 2054. 2058. 2060. 2066. 2068. 2070. 2072. 2074. 2076. 2052 2054 Balance Weights, of brass, nickel plated, with fractionals of aluminum in compartment under glass plate. A very reliable set for ordinary laboratory routine. With forceps, in polished wooden box with lid. Séts;..1 milligram) to: grams... 2 se) does eek eee eae 50 100 200 500 1000 ORES Ob ae ifare tani eaitaraas aesess oases os tor nd ode usetis re etaora Neyer 3.50 4.00 5.75 7.25 10.00 Balance Weights, of brass, without fractionals. A convenient set for use with trip scales, torsion scales, etc. In polished block without forceps. Sets era COweramM ss 5) soo hs ackavie othe ose vamshorebetw Robes ete Yoo 100 200 500 1000 Per SOtts cs pins Leis, aces whe asec Ah Sti he eae ua ial Sere eo 1.35 2.35 3.75 5.75 Balance Weights, Metric, Fractional, of German silver and aluminum. Set of 1 to 500 milligrams, with duplicates of 2, 20 and 200 milligram pieces, in hardwood box with sliding cover, each weight in a separate compartment, with brass forceps. Per set............0 00000 ccc eee nee 2.00 FD a= 5 — Tn | FP) ao 2068 2072 Balance Weights, Metric, for coarse weighing. Of iron, enameled black, with 5 gram weight of brass. Sets; 10: grams: to Istlosien unis sea 2 yaks eae ea eas 1 2 5 10 Total weight; kilos:...c203 ksee nace eater eens ones 2 4 10 20 POR SOE ein ons pagstand hs Re BE RUE Pa a BE OU A RN e Re 4.10 5.50 10.20 16.50 Balance Weights, Avoirdupois, of sealed iron, enameled black. For coarse weighing. Sets, 1/2-02:t0 MSs .0 a dene ae cin ee Rae oe he 1 2 4 T Total sweightsillbsusersne ey an Wei seh dtie eae ot sh ance 2 4 8 15 PGE SCE a2 ele re eo in Srraclnn don a ea come aoe es 2.00 2.50 3.75 6.50 Balance Weights, Avoirdupois, fractionals, of nickel silver. Set from } oz. to 1/128 oz............ 3.15 Balance Weights, Troy Prescription, fractionals, concave, of aluminum. Set from } grain to 10 grains, AN DASLCWOANG NOOK Cs navy ever Msg. ee akeesy cae Reece ava Cats eke NACh ain nse teeta acca ep aces untae .80 Balance Covers, of rubber sheeting. Recommended as a convenient and satisfactory protection to the analytical balance in the laboratory. Size No. 1 is intended for use on Troemner No. 35 Balance, and size No. 2 will fit Troemner No. 50 or No. 65, Newton No. 210 and No. 220, as well as Christian Becker No. 8A and No. 15. Supplied in other sizes on special order only. So arn eA ss a oe eaten SE ee ons Danese aan hes 1 2 Tnside dimensions; InChess¢ 2.2. agave eae eared awe ee anaes 16x 941x171 18 x 914x171 Bae Hg iaa ee a Catecera Nad eatincec tal a la en eral ee 3.50 3.50 Balance Pans, of glass with handle. Diameter. inchesy s-cs0se saan tian ours es maui eee so man Aa eae eects 2 3 Ree pain sce: d ests wie a Seat hice WON eee eas Rabe nue a ane OSE eae 1.00 1.00 Balance Rests, of glass, for use under the leveling screws of balances. HEach...................... 18 10% discount in cartons containing 12. 20% in lots of 144. 68 2084. 2085. 2086. 2087. 2088. 2090. 2091. 2092. | SI : | | l ise WO HN Ae | A 2083 2085 2086 2092 2091 Barometer, Bunsen. Tube only, without mercury, for filling in the laboratory. Graduated in milli- TIVO LOTS the tae seem aU Ree ete acceure tatraprer S Nee ncen aes haat ny Ses Ec RCH Ciera Teta ox cieaegs sem me aoa mes eye oe 6.00 Barometer, Observatory, U. S. Weather Bureau Pattern. Furnished with scale divided in millimeters and reading by vernier to 1/10 mm. Mounted on polished mahogany board with white glass cy | | background to facilitate accurate reading. With thermometer.......................... 46.00 ditto, but with both millimeter and inch scales. On mahogany board.................... 51.75 Barometer Tube, bent, with bulb, closed at one end............. 02.0. e eee eee 3.00 se “straight, closed at one end. nis ke. een eeiia og pee ee ee Gea eee ae eee .80 Barometer, Aneroid, with open porcelain dial showing internal arrangement, 5 inches in diameter, in DiS GNC ASO pe saose eek a ert sap eGie ee Aare Paynes arise dent nce ot acne Beh ein A aes tinted SHE ded stn Re ote 13.50 Barometer, Aneroid, pocket form, as used with Flash Point Testers.......................... 15.00 Barometers, Recording (Barographs), are supplied on special order only, at manufacturer’s prices. Battery, Dry, Burgess Super-Six. A new and entirely different type of dry cell containing over twice the electrical energy of ordinary dry cells of the same size. As the voltage of the dry cell drops during the first period of discharge, an adjustable rheostat should be connected in series where the main- tenance of constant current is important. The Super-Six operates most efficiently at a current drain of not more than 0.35 amperes, and where more than this is required more cells should be connected in parallel so that each cell is not drawn on for more than this amount of current. The operating voltage at 0.35 ampere current drain per cell is under 1.2 volts and the batteries are useful to a minimum voltage of 0.75 volts per cell. Size of battery 6 inches high, 23 inches diameter. 1.00 Battery, Storage, 6 volts, with 5 ampere discharge rate for 16 hours. Dimensions 7; by 74 by 8 inches. Weight 40 lbs. This is the usual lighting and ignition battery which has been found suitable for a great variety of laboratory work, particularly electrolytic analysis, where only alternating eiirrenteiss AVAIIADIO® chen cacy wai ore aa eee ee met aeemates te ad ey wenn ara erent Ghat 30.00 Battery, Storage, 2 volt, 10 ampere hour capacity, suitable for a great variety of laboratory work, but recommended particularly for use with No. 4790 Potentiometer in H-ion determinations in order to secure an unvarying fall of potential, for which purpose it is more suitable than a primary Pat tery nccen con senbawe tee seecises Stee Pen OA Maney cre inl Sas, Weenies Aler Malahat Cigrak atest stsayare mlaas bustapeata 6.00 Note—Both above Storage Batteries can be conveniently charged where only alternating current lines are available by use of Motor Generator Set No. 7390, or Tungar Rectifier No. 8592. 69 2094. 2095. 2096. 2097. 2098. 2100. 2102. 2104. 2106. =—_ MrT sre HLH un ti A.H..Co. lt uniting A 2097 Battery Binding Posts, of brass. Style RC Soke eg See erred 2 aes ere a asain oe evar ca ain oe eben Sone ly Radel -20 25 25 35 10% discount in carton of 12. Battery Connectors: Stylésnc sanction 4 oe ddh eee oh eelnae ae adel as BEAT B C a Chet esta otc teva es aN rene ae eee Oo usta Re ee 20. «2525 10% discount in carton of 12. Battery Connector, a U-shaped, nickel-plated terminal screwed into hard rubber handle; specially made for the connection of precision electrical measuring instruments such as supplied for conductivity and potential measuring outfits. For satisfactory use in such work they should be soldered to single conductor silk fixture cord as listed on page 619. Each............ 0.0.0.0 0000 cece eee .40 Battery Jars, cylindrical, white glass, hand made. Diameter, inches...............000 ee eee 4 3 4 5 6 9 9 Height: inches: sc¢ Re Te A Uo: H. T H O M AS GO M P A N Y¥ BEAKERS Pyrex Glass G-702EJ is a low expansion borosilicate glass of simple chemical composition containing no metals of the magnesia-lime-zine group and no heavy metals. It does not begin to soften below approximately 800°C and the average solubility toward distilled water of an exposed area of 100 square centimeters is 0.00015 gram. The linear expansion coefficient is 0.0000032. Because of the above physical properties of Pyrex glass, beakers made of it are superior to any hereto- fore made in Europe or America in resistance to heat shock, resistance to mechanical shock and in stability (sta- bility toward distilled water being accepted as an index of this important characteristic). These superiorities result in so little breakage in actual use as to make Pyrex beakers lowest in final cost to the user. For data regarding the comparative tests made at the Bureau of Standards see, ‘“‘Comparative Tests of eo Glassware’, by Percy H. Walker and F. W. Smither, Journal of Industrial and Engineering Chemistry, ecember, 1917. Our stock of from 2,500 to 3,000 cases of Pyrex ware, ready for immediate shipment, is said to be the most extensive in existence and we have maintained our position as the largest distributor of this ware since the first announcement of it in our advertisements of October, 1915. 2110—(‘th actual size) 2110. Beakers, Pyrex ee Griffin low form, with spout. Capacity, ml. . pe eo) 50 100 150 250 400 600 800 Wale Aten nce ee ee 18 18 19 21 25 .30 .35 -40 10% discount in case of. . 312 216 156 156 168 84 G2 48 Capacity, HN Pa cicigaen ered te unences 1000 1300 1500 2000 2500 3000 4000 CN oye Feat shoal kesh) aed acces xe 54 .65 73 -98 1.20 1.40 1.80 10% discount in case of....... 48 24 24 12 12 10 10 2116—(! ith actual size) 2116. Beakers, Nonsol Glass, Griffin low form, with spout. Gapacitysemlls,, ccc areen awe ae 30 60 90 120 150 180 250 300 aC Gosh eens en aes ais 15 15 16 18 19 19 21 23 5% discount in case containing.... 144 144 144 360 288 288 144 144 Capacity ml vee aes eae Sees 350 500 600 700 1000 1400 2000 Chics e vice eee ane au maine eae ae MeO: .32 3D 38 57 -79 1.04 5° discount in case containing........ . 144 144 144 72 72 36 36 2122—('th actual size) 2122. Beakers, Pyrex glass, usual or Berzelius form, with spout. Capacity, ml..........--.- 100 150 200 300 400 500 600 800 1000 Bach coe seis airtel eaten 9 21 23 26 30 32 35 .38 54 10% discount in case of.... 156 120 168 144 60 60 60 48 36 71 Ay RE UA 2128—(} actual size) 2134 2128. Beakers, Pyrex glass, usual or Berzelius form, without spout. Capacity, ml.............. 100 150 200 300 400 500 600 800 1000 Bae hiss conc eens nieoeeres 19 21 .23 .26 .30 32 .35 38 54 10% discount in case of.... 156 120 168 144 60 60 60 48 36 2134. Beakers, (Dye Pots), Pyrex Glass, high form without spout. Specially made for use as dye pots, but suitable for many other laboratory purposes. The 400 ml beaker fits Dye Baths Nos. 4740 to 4750, while the 600 ml beaker fits Dye Baths Nos. 4754 to 4760. DAI ECS a team MMMM een cee. lehentsirc ae ae atk meets d eraak at cbeeatclsg tothe ane sleet Ghieenece palates 85 90 ne OL DOs STINT beat face tiers hid en yatta k ec Mraat ogy a IR a Ag I As ote oa eel 65 80 ROTO GMs 208 eck Ay ani na eaien esa ati ora ys oR ache clasece wie une cae Ga Raa eae 150 150 Wapacl b yar re cee ee atari e Ae aaa tat ta er aca Aten ont ewan MUO mr saan teins mine RINE 3 hos 400 600 PCN Sere css dakn Ried Ne Oh he Sahin Nes Be aL Meath Nad nace cogiih dnd eh ath .60 -70 | | | {| Ajeet wl | , nen Wl eee Hl amrce. 2138 2139 2140 ; 2142 2148 2138. Beakers, Conical, with wide flaring lip, without pourout. Sometimes designated as Phillips Beakers or Assay Flasks. Capacity; nls aisreiusies yeas poses ek Meet 60 120 250 500 1000 Bache. es35% SB EMRE A Sate A GSA NUAN Ree bah Pveutg 25 30 .35 45 75 10% discount in case containing................ 144 144 144 60 36 2139. ditto, but with pourout. Gapacity my 2 ees ob rie ete aets cern nia mua § 60 120 250 500 1000 2 Sea ee ee Skene oe ncnie tat 20 25 35 40 55 10% discount in case containing................. 144 144 144 60 36 2140. Beakers, tumbler form, of heavy molded glass, with pourout. Capacity 7 ounces. Will not stand heating over flame because of weight of glass......00 0.000 18 2142. Beakers, of heavy glass, high form, with flaring lip and pourout. Will not stand heating over flame because of weight of glass, but is found useful in many laboratory operations such as sugar filtration and other purposes for which precipitating jars are used. Capacity; OUNCeSas. cso haat eee Senta a 2 4 8 16 382 Bach. ens ele icee ans SAG i ee cae eee 16 .25 35 .40 -60 10% discount in case containing................. 420 240 120 60 36 2143. Beakers, heavy glass, with wide flaring lip and pourout. Sometimes referred to as “Sugar Flasks.” Will not stand heating over flame because of weight of glass. Capacity, ounces 32 85 48 2146. Beakers, Opaque Silica, Glazed, low form, with lip. Eapachtysemalviay nison duces wneud Ceae ere nee Rcd aint Mevcen cedars ea) ae oon 50 100 150 a Chi ssenceer aioe es Ae eae ead a Nia eae ceed tat hee A eieed ON Un Tht hcl as ante yaaa 2.50 2.75 3.05 2147. Beakers, Transparent Silica, low form, with lip. Capacity, Wale a ibe Nee cok gta teee uate Ren cun anata lvoe aioe cnt 50 100 150 RAC Hess pect interpre e fy cs CNA cede lve or eoree anmeeah eet als 21.6 seca eacteaeae ie Nova tk one te 4 9.75 15.75 18.00 A R T H U_ R we HAN) Tr 2150 2153 2150. Bell Glasses, low form, with groundrim. Very convenient in the laboratory for covering small dissections, prepared slides, fecal preparations, etc. Insidecherghtsin chess hate cactlek citar aie Sa ete Deel heaton ra ata gu R ohias 28 24 Insidediametens in ches, o/c H ccalesanee ah gdtcer i nari ugh ais delta Pa shoe i aes 4 5} LOY: UR rey Wee a ase a enor tira tra Ate Berean Renee aM er men monies aad Ps eee ay PPE Pee .65 95 20% discount in case containing.......0 00.000 e eee e eens 96 72 2152. Bell Glasses, low form with ground flange. Heights in Chessg 40.6200 2st ed) an aaete eae eX 4 5 8 10 at Diameter, inchest aso Snsiaceretens A reer cs 6 8 10 12 16 Each. Re each teers a varie ia tren ete Asetee eens Sey SNe AAR 2.80 3.70 6.00 8.50 12.80 _ 20°% discount in case containing............. 36 15 8 6 2 2153. ditto, but high form. Size 15 x 8}-inches is suitable for use on Microscopes F, FF, FS, FFS, etc., while size 18 x 9 inches is suitable for use on the larger stands, such as CAE, CAS and DDS. Height, inches.................. 9 11 14 15 18 18 Diameter, inches................ 5 6 63 84 9 10 AGI oe Ose oe et Ge eat eee 2.50 3.40 3.70 6.40 8.75 16.65 20% discount in case containing... . 18 12 9 4 2 2 2154. Bell Glasses, high form, with more or less square top, suitable for covering microscopes, etc.; flange not ground. VOLS G S10 CCS scat Ps bocce et lets ees Oe IE MTA ee CSER iy ad TOS Hote ss oT 13 15 Diameter anChess 15 eae ota tenet N Cae heath ie Sener ROE RAN Ch he de een toh 8 9 EC ager ae ee she eg en eart hn et ent anak ATER Ty Seas iar thin vetted wa Race ne 3.90 6.00 IMENT 0 9) A.H.T,CO- 2156 2157 2159 2156. Bell Glasses, high form, with open tubulated top for stoppering, with ground flange, and without stopper. Height, 1ichesic. sats Sek ie ed eo cee hatin eee eral wane Anite ea aed Oa A 11 15 18 DIBME LEH ID Cesta s be cad erase tuner Meee enced ia eae ea ocd Geta 3 83 10 EC ghee oA Ride) aren oictcee eae cles sealed een os a itanlape rast Sena oe enantio 3.40 6.30 17.50 20% ee dn. CaSe°CONGAININ Beco ert hrcatde ales wees THE OS BS 12 4 2 . itto, but with glass stopper. mn Height, aehes eee oe SA RUNG tava AMS eauet PEMA Pato ES 9 11 15 18 Diameter; Inches); 24 sosausiee es ca eeer ck eee eee bans 5 6 83 10 | DEV (Renate anes ERNE enn ee eH Ere PCN CR er anes eee at ane ate e ee Rear ar aa 2.80 3.50 7.85 18.00 20% discount in case containing....................00, 18 12 4 2 2158. Bell Glasses, high form, with wide opening at top and ground flange. HCIG HES IN CMOS cer seipaste elves, haste cs maestro tat ceeecceasvocne strat tienes 9 11 15 18 Diameters In Chests mx weve cicesice wich wise sere Sa Sioa den aud acal 5 6 83 10 AGIA ool ears Se a eet aaa aanst aks 2.50 3.30 6.30 16.65 20% discount in case containing...................008. 18 12 4 2 2159. Bell Glass, open top and ground flange, for use in making dialyzers, 5 inches diameter by 8 inches high. 2.50 73 Ayu ni oll = AMT co. 2160. Bell Glasses, with open top, tubulation near bottom and wide, well-ground flange. Suitable for use on an air-pump plate. Height. min 26. oet rcs sh ee era ek Bt Rea oot, No ane oe Be Che oe ae cece 3800 300 PPTATST ET WTI, a4 feles eat soe Sis ch eet seo eesesteie Sig acne Runa cabtidel cok ene teAl Say penton ma Sine d ayn gestalt Bee _150 200 ACN etre te cusn neh Coon te ee ide te Reins Altes aN oC Be he chide ogee OP evan gre Ratatat 4.40 6.00 2162. Bell Glass, double walled, with ground-in glass stopper. The jar may be filled with colored fluid acting as a ray filter for determining the effect of various rays on plant functions, ete. Heights os xorgs weno: are eee yas Ses aad eee Be BN idee tds sce ak 300 400 Diameter minis Gacy 5 n2u eae Be as ee ee St el ER Ve het arth oo 120 150 VC ea rae aden set cSt fe eed re eo ee Nae eT ye EE 2a Oe SE ET iP GAY gre ee RE 7.00 8.50 2166. Bladders, Animal, dried, assorted sizes. Per dozen............... 00... c ccc cece cece e teens 2.40 2168. Blocks, Embedding, for celloidin sections. Of hard vulcanized fibre, and of such weight to sink the specimen in the jar in an upright position. The fibre is reddish in color, which permits legible writing with lead pencil. Each block is slotted to provide firm hold for the celloidin. SIZE IMCHESE, saree ee cuba aise tenant $x3xi 3x23x3 xix? lx1ilx#? Per M00 ek Adee ta eres Oo ieee bce 3.50 4.00 5.00 7.50 2170. Blowers, Foot Power. These blowers produce a powerful and continuous blast, the pressure of which may be increased by adding one or more rubber discs to the air reservoir. Diameter of air reservoir, inches.....................0.0.00.0.0.. Tt 9 11 PCa a Nees ng aug mee ety ai eet Gidles dha ate Bren Aare oeke aray pie ae 9.50 12.50 17.25 2171. ditto, but-mounted on legs. Eachi...3 0... cee ret cee een a acess 10.75 14.25 19.50 2172. Rubber Discs for above Foot Blowers. These discs are cut from steam-cured sheet rubber which is made of the best Up-River Para and contains no other ingredients than the necessary sulphur for curing. Will last much longer than discs cut from ordinary rubber sheeting. Diameter inches: 2.3 acs. sae Nstaereh el savin eaeiacu re eae ten eee = 114 143 Ba iter seared ee eee ayers teeta eee rey rennet ee 50 15 1.00 2173. Nets for above Foot Blowers. Each.................................. .40 .50 .60 2176. Blowpipe, of brass. Terie blastn so ces eee eaten een re a eae ep eee sey anege Sar Sacteees ON RAE Rel ate ara 200 250 3800 ACH des cao se etayat eS es ee te er Poth tao Veg 8 ca Neo Tee aaa 18 20 22 10% discount in lots of 12. 25% discount in lots of 144. 2177. Blowpipe, Blacks’, of japanned tin, with removable IDEASS TUN ys osha deeds dihabe th sce wea es Soe ee Deeg. g -15 2178. ee “of brass, with screwed-on tip, and wooden mouth-piece...................0 00. -70 2179. Mouth-piece for Blowpipes, of hard rubber, new form, to fit blowpipe, inside diameter, mm. 6 7 8 Te et ert re ye eal en eee th een Oe ens es cba eee Aka e Dy alee Cink anna eset Mn oe 2h5 NN -40 .40 .40 2180. GittO, DUtcOb WOO so kt coat windilneen eee atc wetness aa mis ween rens Tansy conn teats Nemeth a.) 12 12 .12 74 2181. Blowpipe, Plattner, with hard rubber mouth-piece but without platinum tip..................... 1.90 2182. Platinum Tips, detachable, to fit Plattner Blowpipe. Market price of platinum. 2183. Blowpipe, Berzelius form, of brass, extra fine finish, with hard rubber mouth-piece and platinum plate placed on end of jet. A very satisfactory form........0.00 0000 ccc eee 3.00 Blowpipe, Charcoal, American, willow, of fine uniform grain, 4x 1x } inches. Perdozen......... .95 i SET OF | PIPE APP, | oo ARary . We ian thy) 4 BTEO. 2188 2193 2188. Blowpipe Set of Apparatus and Reagents, as designed by Prof. Butler of the Colorado School of Mines for use in the laboratory and in the field. Each piece is so arranged as to prevent any breakage; outside dimensions 112 x 64 x 2% inches. Complete including wet and dry fluxes and alcohol BIG. OLA: LAMM PSes ieee sess cee poe veo ee GR in ees aM Stele ead er MA aint ds oe pee 30.00 The outfit consists of the following:— Blowpipe Anvil Cobalt Nitrate Bismuth Flux Platinum Wires and Holder 3 Arsenic Tubes Hydrochloric Acid Borax Combination Charcoal Borer, 2 sticks Charcoal Sulphuric Acid Potassium Bisulphate Magnet and Chisel 6 open Tubes Nitric Acid Oil Lamp, brass Streak Plate Large Test Tube Tin Alcohol Lamp, brass Blue Litmus Small Test Tube Microcosmic Salt Hammer Red Litmus Ammonium Hydrate Sodium Carbonate Platinum-Tipped Forceps 2189. Pocket Handbook of Blowpipe Analysis, by G. Montague Butler, E. M......................... 1.00 2192. Boilers, or saucepan, white enamel ware, blue trimmed. These goods are made of seamless steel and the enamel is both acid and fire-proof and distinctly superior to the ware usually sold for household purposes. Very convenient for use in the preparation of culture media, etc. With cover. Size; iN CHES) 574 ows eh cee egtens rr atarsyste oaetine eu aimlat& Saad darn ied we aatotnsates weap Aan 61x 4} 83 x6 Capacity, Quarts... 3.5, ocean es oa ane aren ee Coe ee eg S 2 53 Bac hisomesahaecre hark Rio cores sas ee ep tae aire So oeSa hemes peel aae a Sarah rate dae ere 1.20 2.30 2193. Boilers, or saucepans, double, same quality as No. 2192. The capacities given are for the inside boilers. Gapacitys quarts, 67 ccs suGe coin cia nea enema sa nae ares ie 23 38 Bea Chie esis essa ESR et Se AE A eek ca Shee AoA Gooch Baek ES 2.30 2.90 4.00 Bolting Cloth, Standard Silk, as used in making sieves; 40 inches wide. Not carried in stock, obtained on special order only. Mesh per lineal } inch must be specified when ordering. Bomb, Parr Sulphur, see page 561. 15 bl Ua H. TE Oo IMP Ae US Cc oO” M —-P A UN: —Y¥ i i Hl ANH.T.CO- BOTTLES, COMMERCIAL ik i aff om | Aira oc ll 2200 2202 2200. Bottles, Narrow Mouth, flint glass, for cork stoppers. Capacity, ounces................ 3 1 2 3 4 6 er COZON Es heh nh-c vse a eres ees 59 63 .70 85 97 1.10 25% discount in case containing... 864 864 720 576 432 360 Capacity, ounces................ _ 8 10 12 16 382 64 Per dozens iii hc ecds Act A et 1.32 1.44 1.68 1.80 2.76 3.60 25% discount in case containing... 288 216 216 144 96 48 2201. ditto, but of amber glass. Gapacity; OUNCES! as 2s eeder ee tect a Se 1 i, 4 6 8 EAs) gat (OVAc) 1 Leeemrete Riere tire Pe ieee Rants emia er cree ence, Sa .63 -70 97 1.10 1.32 25% discount in case containing............. 864 720 432 360 288 Capacity; OUNCES: 2 nni ee Aiea eee ue oR BSG eealane eS 12 16 32 PP ORDO ZOMG ho) crc BS Saye tect op geese eet ial aa a sarge ge alg cacao 1.68 1.80 2.76 25% discount: in case containing. ».... 006 has be ca cee cee eee ee 216 144 96 2202. ditto, but green glass. OapaClty sc: ais hes ot eed eee ed 8 oz. 16 oz. 1 qt. 3 gal. 1 gal. 2 gal. 5 gal. ACh a covet open erie een eee 10 14 .20 .33 55 1.35 2.30 25% discount in case containing.. 288 144 96 48 36 12 6 2204. Bottles, Wide Mouth, flint glass, for cork pie Capacity, ounces................ 1 2 8 4 6 PeriGOZEMe 6.0 ch oes hk ca a ae 60 65 ahi 88 1.00 1.15 25% discount in case containing... 864 864 720 576 432 360 Capacity, ounces................ 8 12 16 24 32 64 Perdozen isc ee ee es es ees 1.32 1.68 1.92 2.64 2.88 3.72 25% discount in case containing... 288 216 144 120 96 48 2205. ditto, but amber glass. Capacity, ounces............... 1 2 4 8 16 82 PEE GOZEN ic ets ens ee es -65 72 1.00 1.30 1.90 2.85 25% discount in case containing.. 864 720 432 288 144 96 2206. ditto, but green glass. Capacity .4.0 ene taWeharneere o& 8oz. 1602. 1 qt. 3 gal. 1 gal. 2gal. 5gal. Bachinshnaieaex ances ee 10 14 .22 33 55 1.35 2.30 25% discount in case containing.... 288 144 96 48 36 12 6 2208. Bottles, Wide Mouth, Square, flint glass. For cork stoppers. The 1-oz. bottle is the shape and size used in the standard acid test for aromatic hydro-carbons. Capacity, ounces......... 1 2 4 6 8 12 16 82 Per dozen............... 65 75 1.00 1.15 1.20 1.68 1.96 3.00 25% discount in case con- CAINING oss See aoe 864 720 432 360 288 216 144 96 2209. Bottles, Wide Mouth, Rectangular, flint glass, for cork stopper; 8 oz. capacity. As used in many labora- tories for growing mass cultivations of bacteria. Per dozen................. i sapaite sh Mesudey ae ucbes aoa nec NO ANC vei Neto t av uel a amen Sue tes ita 1.10 20% discount in carton containing 72. 25% discount in case containing 288. Note—Corks are not supplied with Bottles Nos. 2200 to 2209 at the prices given. A suitable selection of corks is to be found on pages 191 and 192. 2212. Bottles, Acid, Narrow Mouth, green glass, with vertical glass stopper. Capacity arciy eka een ate setae 3 pt. 1 pt. 1 qt. 3 gal. 1 gal. 2 gal. Bache onic swt han eames Siete ees ett .27 34 -46 75 1.05 2.15 25°% discount in case containing......... 144 144 96 48 36 12 A 2220. 2221. 2222. 2223. Reo oe UR H. T H O M A > BOTTLES, LABORATORY 2221 Bottles, Laboratory, Narrow Mouth, with flat glass stopper. nh tui 222 Go hes i 2, 2224 M P A 4000ml ~ uy hi i tly 2223, 2225 These bottles are made in our own private moulds of a new formula lime glass, developed under our direction, and which, while not equal to Pyrex, Nonsol, or similar glass in stability, is far superior in this respect to the ordinary flint glass mostly used in the manufacture of bottles. They were the first bottles to be made in the U. S. of the squat shape, heretofore available only in imported bottles. They hold the full capacity indicated, and are of excellent appearance and suitable in every way for use as reagent bottles where labeling is done in the laboratory. Capacity Mls cwaseclscoe cause emit 125 250 500 1000 2000 4000 ACHR sec taeoaeorath aor se dy oak hee -26 .33 43 .60 1.25 2.00 25% discount in case containing..... 100 100 100 50 30 15 ditto, but wide mouth. Capacity; mls ke sen aie te aed ae 125 250 500 1000 2000 4000 ache 5 ee vnceotace cen ocr ven A cet eee .30 34 .45 65 1.35 2.15 25% discount in case containing..... 100 100 100 50 30 15 Bottles, Narrow Mouth, of flint glass, with high, ground mushroom glass stopper. This bottle has a fine fire polished finish approaching shop furniture ware and is much superior in appearance to iron mould finish. Capacityeo tna penec aca d enamine 6 oz. 8 oz. 12 oz. 1 pt. 1 qt. PACH nets othe ft cusce ohn oak Bok 45 -50 -60 -70 .80 5% discount in case containing....... 72 72 72 72 36 GAapacibyecmern ike cae Ay earns Hee Ox euirns Aue eneaneae 2 qt. 1 gal. 2 gal. 3 gal. PIA CHS .sioeel se hts crue n cgameee ct mi reheat, Saar MG Rental peace Nt 1.50 2.15 4.35 7.00 25% discount in case containing.................. 12 12 6 4 ditto, but wide mouth. CAMA Ciiy as nurs Aca cones uenaehon atone yee sae 6 oz. 8 oz. 12 oz. 1 pt. 1 qt. Ha chiven suet elke aes anes 48 .60 .65 75 1.00 25% discount in case containing....... 72 2 Wz 72 36 CAPAC Yes larg a Sens hake Baan Satsonnatlns wasn pecoupedenon 2 qt. 1 gal. 2 gal. 3 gal. Bach 2 Se poe eh Le he ee a 1.70 2.25 5.00 8.40 25% discount in case containing.................. 2 12 6 4 ACR -F Ho PUP oR H. T =H © «M A $s Ce Os uM Ro A INE oe 2224. Bottles, Narrow Mouth, of flint glass, with high, ground mushroom glass stopper; identical in shape to No. 2222. These bottles are made in iron moulds and are, therefore, without the high polish and finish of bottles No. 2222, but are recommended as a thoroughly satisfactory bottle for all ordinary laboratory purposes. (GADACIEY cee teak antes ares atin mutex GRO 4 02. 1 oz. 2 oz. 4 oz. 6 oz. Per dozen so. kei ve wy en eee 1.70 1.85 2.00 2.45 2.85 25% discount in case containing....... 864 864 720 432 360 Capacity Bi Ys Aare elas eactth wan baacwa kB ha Me hates 8 oz. 12 oz. 16 oz. 32 oz. NEVO) epee aed ay eeha aedy ects tana gmt se nen ns terra rt renee ive esa 3.00 3.72 4.20 5.76 25% discount in case containing.................. 288 216 144 72 2225. ditto, but wide mouth. The # oz. size of this series is that used in mailing blood cultures in Was- sermann Mailing Case No. 6360. Gap acity.a5 estar a eins oe ta ene 4 oz. 1 oz. 2 oz. 4 oz. 6 oz. ORO ZEN Jobe ch on ec gS cei ao 1.80 1.90 2.15 2.55 2.90 25% discount in case containing....... 864 864 720 432 360 CAPACI Yes Lincs. (54x cece eeclacs daeel oh teases abn es Mec uiead 8 oz. 12 oz. 16 oz. 32 oz. aC lipase ee ee oe rayne ea caked noes ae eee 3.12 3.84 4.20 6.12 25% discount in case containing.................. 288 216 144 72 2226. ditto, but of amber glass, wide mouth, Capacity, OUNCES hs 9 ki bo ces A Al eseciee dan © eatgesnvn gdh Sua aun mane aeeaty URNS at oaseowans 1 4 POP OZ M65 oko aaa ee eee ae ad oy a had ees dctegl cd de oe eGo ee BBR AIGA UN A 1.90 2.50 20.75 discount in: case UM EP Ar IN OF. 2302. Reagent Bottles, Narrow Mouth, 250 ml capacity, as above described, with labels as follows: Wachteur oan lteter es dO) Per dozen............... SP on 11.88 No. Name Symbol No. Name Symbol 652. Acetic Acid HC2H;02 687. Magnesia Mixture........... 653. Alcohol. . C»H;OH 688. Magnesium Sulphate... MgSO, 654. Alcohol Absolute C.H;OH 689. Mercuric Chloride..... HgClz 655. Ammonium Carbonate....... (NH4)2COs 690. Mercurous Nitrate. . Hg2(NOs3)2 656. Ammonium Chloride......... NH.Cl 691. Methyl] Alcohol. CH;0H 657. Ammonium Citrate.......... (NH,4)3CcH;0, 692. Nessler’s Solution............ 658. Ammonium Hydroxide . NH;sOH 693. Nitric Acid........ : .. HNO: 659. Ammonium Molybdate....... (NH4)sMo7O24 694. Nitric Acid, Con............. HNO; 660. Ammonium Oxalate ...(NH4)2C204 695. Nitric Acid, Dil............. HNO; 661. Ammonium Phosphate.......(NHa)2HPO1 696. Oxalic Acid...............5- H2C204 662. Ammonium Sodium Phosphate.NaNHsHPOs 697. Phosphotungstic Acid........ (P205.24WO3.xH20) 663. Ammonium Sulphide (amber)..(NH4)2S 698. Picric Acid.................CeH2OH(NO2)s 664. Barium Carbonate........... BaCO;3 699. Potassium Carbonate........ K:CO3 665. Barium Chloride. ...BaClh 700. Potassium Chromate......... K2CrO4 666. Barium Hydroxide ...Ba(OH)2 701. Potassium Cyanide ...KCN 667. Barium Nitrate... ... ...Ba(NOs)2 “702. Potassium Dichromate.......K2Cr207 668. Calcium Chloride pease CaCle 703. Potassium Ferricyanide.......KsFe(CN)s 669. Calcium Hydroxide. .........Ca(OH): 704. Potassium Ferrocyanide......KsFe(CN)s 670. Calcium Hypochlorite. .......Ca(ClO)2 705. Potassium Hydroxide........ KOH 671. Calcium Sulphate............ CaSO4 706. Potassium Iodide............ KI 672. Carbon Disulphide........... CS2 707. Potassium Sulphate. . . -K2SO4 673. Chloroform ee CHCl; 708. Potassium Thiocyanate....... KCNS 674. Cupric Sulphate. ... . CuSO 709. Silver Nitrate............... AgNO: 675. Ether... .. Cenc fA Slees (C2H5)20 710. Sodium Acetate.............NaC2H:02 676. Fehling’s Solution....... ne 711. Sodium Carbonate...... Na2CO3 677. Ferric Ammonium Sulphate... FeNH:(SOs)2 712. Sodium Hydroxide........... NaOH 678. Ferric Chloride.......... ...FeCls 713. Sodium Phosphate........... NasHPO, 679. Ferrous Sulphate............ FeSO, 714. Sodium Tungstate........... Na2WO. 680. Hydrochloric Acid........... HCl 715. Stannous Chloride........... SnCle 681. Hydrochloric Acid, Con.......HCl 716. Sulphanilic Acid... CoHs(NH2) (SO3H) 682. Hydrochloric Acid, Dil....... HCl 717. Sulphuric Acid......... .-H2SO1 683. Hydrogen Sulphide (amber) ...H2S 718. Sulphuric Acid, Con.........-H2SO4 684. Hydrogen Sulphide Water..... 719. Sulphuric Acid, Dil...........H2SO4 685. Lead Acetate...............- Pb(C2H302)2 720. Blank 686. Lead Subacetate. _.....Pb20(C2H302)2 2303. Reagent Bottles, Narrow Mouth, 500 ml capacity, as above described, with labels as follows: Haehiie ae iid iad etenerrs 25 cies 2 ate 1. Per dozen ies cco ce Saeco Hh hea RE ee 14.04 No. Name Symbol No. Name Symbol 721. Acetic Acid. ....... ai caaro eet HC2H;02 748. Sodium Phosphate. ..... ...-Na2HPO, 722. Ammonium Carbonate.......(NH1)2CO3 749. Blank 723. Ammonium Chloride......... NH,Cl 750. Solution Acid Arsenious N/ 724. Ammonium Hydroxide.......NH:OH 751. Solution Acid Nitric N/ 725. Ammonium Hydroxide, Con...NH:OH 752. Solution Acid Oxalic N/ 726. Ammonium Hydroxide, Dil....NH:OH 753. Solution Acid Hydrochloric N/ 727. Ammonium Sulphide, Dil... ..(NH4)2S +Aq 754. Solution Acid Sulphurie N/ 728. Ammonium Sulphide (Amber) . (NH3)2S 755. Solution Ammonium Hydroxide N/ 729. Barium Chloride............BaClz 756. Solution Barium Chloride N/ 730. Calcium Hydroxide ...Ca(OH)2 757. Solution Barium Hydroxide N/ 731. Calcium Sulphate. . ..CaSOs 758. Solution Iodine N/ 732. Ether..... slat oh (C2H5)20 759. Solution Potassium Bichromate N/ 733. Ferrous Sulphate... .. FeSO. 760. Solution Potassium Hydroxide N/ 734. Hydrochloric Acid... . HCl 761. Solution Potassium Permanganate N/ (Amber) 735. Hydrochloric Acid, Con...... HCl 762. Solution Sodium Carbonate N/ 736. Hydrochloric Acid, Dil. HCl 763. Solution Sodium Chloride N/ 737. Nitric Acid.......... : HNO; 764. Solution Sodium Hydroxide N/ 738. Nitric Acid, Con........ HNOs 765. Solution Sodium Thiosulphate N/ 739. Nitric Acid, Dil. . ° HNO; 766. Solution Silver Nitrate N/ (Amber) 740. Potassium Chromate. . ....KeCrO. 767. Standard Solution Uranium Acetate 741. Potassium Dichromate.......K2Cr20;7 768. Standard Solution Uranium Nitrate 742. Potassium Hydroxide........ KOH 769. Standard Soap Solution 743. Sodium Carbonate.... Na2COs3 770. Starch Solution 744. Sodium Hydroxide. . NaOH 771. Molybdate Solution 745. Sulphuric Acid............-. HSO; 772. Fehling’s Copper Solution 746. Sulphuric Acid, Con.......... HoSOs 773. Fehling’s Alkaline Tartrate Solution 747. Sulphuric Acid, Dil..........H»:SOs 2304. Reagent Bottles, Narrow Mouth, 1000 ml capacity, as above described, with labels as follows: Bachys esc a hate inck cro eee 1.58 Per: dozen ies i cin tol dain saa mee ES 7.06 No. Name Symbol No. Name 774. Ammonium Hydroxide, Con...NH:OH 789. Solution Barium Chloride N/ 775. Ammonium Hydroxide, Dil. ..NHsOH 790. Solution Barium Hydroxide N/ 776. Hydrochloric Acid, Con.. HCl 791. Solution Iodine N/ 777. Hydrochloric Acid, Dil....... HCl 792. Solution Potassium Bichromate N/ 778. Nitric Acid, Con.... HNO; 793. Solution Potassium Hydroxide N/ 779. Nitric Acid, Dil. peau bak LINO s 794. Solution Potassium Permanganate N/ (Amber) 780. Sulphuric Acid, Con.......... H2S04 795. Solution Sodium Carbonate N/ 781. Sulphuric Acid, Dil..... ‘ H2SOs 796. Solution Sodium Chloride N/ 782. Blank 797. Solution Sodium Hydroxide N/ 783. Solution Acid Arsenious N/ 798. Solution Sodium Thiosulphate N/ 784. Solution Acid Nitric N/ 799. Solution Silver Nitrate N/ (Amber) 785. Solution Acid Oxalic N/ | 800. Standard Solution Uranium Acetate 786. Solution Acid Hydrochloric N/ 801. Standard Solution Uranium Nitrate 787. Solution Acid Sulphuric N/ 802. Starch Solution 788. Solution Amonium Hydroxide N/ 803. Standard Soap Solution 2305. Reagent Bottles, Narrow Mouth, as above described but entirely blank, 7. e., without enameled shield and label, for labeling in the laboratory. Capacity; ml. acc: 5.0508 saci eee 50 125 250 500 1000 Ha Che rah ose aye cooatt less ennqcnaericlies ita iad any senenede 35 42 .60 70 95 Per:dozen’. 2 ieee an eee HE ee ae 3.78 4.54 6.48 7.56 10.26 2306. Reagent Bottles, Wide Mouth, 125 ml capacity, as above described, with labels as follows: Bachitasts can esol lecctnat ieee 1.00 Per dozeniyk4 iis oy en te ee eee Wien aes 10.80 No. Name Symbol No. Name Symbol 804. Ammonium Chloride.......... NH:Cl 813. Potassium Iodide............ <1 805. Ammonium Sulphate........(NH4)2SOs 814. Potassium Nitrate........... KNO; 806: BOLaks 6 tieauesethd aan eeee Na2Bs07.10H20 815. Sodium Ammonium Hydrogen 807. Cupric Sulphate............. CuSO1.5H:0 Phosphate..........+-20+5+ Na(NH)HPO;+4H20 808. Eschka’s Mixture 816. Sodium Carbonate. ....Na2COs3 809. Ferrous Sulphate....... .-FeSOs.7H20 817. Sodium Nitrate. NaNO; 810. Picric Acid.............. CeH2OH(NO2)3 818. Sodium Nitrite.............. NaNO2z 811. Potassium Chlorate KC103 819. Blank 812. Potassium Cyanide.......... A €---- 50 MIM--- > —_> | sin 4 a LT 3 an ' 1 5 ' hs M S : Lie a a | i ai Mi | Mi La es 7 ml l. ae Tl H ‘ 30cc so -ce 100 ce 2321 Bottles, Specimen, wide mouth, of flint glass, for cork stoppers. Ca aclty7-OUNCOSR rigs ae on 8 Septet are mee Baan nena yk Soraiournaud ay ale ee ae 3 25 34 Take Corks No. 4054, size number....................0.0.0.000. 11 13 18 Per dozen; ‘without: corks 3:46 vee Leis eo besos wha s sivas -70 .80 92 20% discount in carton containing 86. 25% discount in case containing 144. Bottles, Specimen, of flint glass, with extra wide mouth for cork stopper; made exclusively for us in our own private moulds and packed in cases of convenient size. These bottles are of a shape designed especially for the convenient storing of histological and other specimens for section cutting, ete. There is no regular stock bottle of the same shape and dimensions in the same series OPISIZES» CAD ACI LYS IM irene mas oecer eh nr eae ila gt te tony nn asin 30 50 100 Perl0....... cults Sat ahaa hte bine aN a tear eae ope etntces 80 90 1.50 25% discount in case containing 100. Corks, for use with No. 2321 Specimen Bottles. Catalogue numbers..... 4056 4056 4058 Diameteriattop; Inches is cache nolo: onc tes eek men cde eee ene tree Ga $ 13 13 POT ANOO 2 cs torre cme tnete iii cattle pester kG Ne here ip ap ee ck cer Ge 1.42 1.74 3.33 2329. 2330. 2332. 2334. 2335. 2336. 2337. 2338. 2339. 2340. 2341. 2332 2336 2340 Bottle, Specimen, with extra wide mouth for cork stoppers. Capacity 4ounces. Each........... 10 20% discount in carton containing 36. 25% discount in case containing 144. Bottles, Sputum. A heavy green glass bottle, 2 inches high by 1 inch diameter; for mailing sputum and other samples inside of mailing tubes, as required by the U. S. Post Office Department. Widely used in Board of Health work. Without corks. Per gross............................. 5.50 15°; discount in case containing 7 gross. ditto, but; with-corks:to:fiti tight: “Per gross%. scien Sead he es Ea ee 7.25 15% discount in case containing 7 gross. Bottle, Sputum square, 10 ml capacity, with extra long cork; as used in Trunnion Cup No. 3103 on Size 2 Centrifuge, and in Shaker Heads No. 3046 and 3099. Perdozen....................... 85 PER GEOSS#) 0 eich on nega ie steele 9.25 Bottle, Vaccine, of glass of low alkali content, with special red rubber stopper. This stopper is perforated to within about 1 mm of top for puncture with the syringe needle at time of withdrawal of con- tents. The puncture in the stopper seals itself hermetically after withdrawal of the dose, so that contents may be used for as many doses as necessary until bottle is empty. Complete with special rubber stopper: Capacity; ml... 2.2 6004s eso 5 ca bade key Shee a hes 30 60 Per dozen, in carton of 1 dozen... 1.1.0... cece nee nes 1.90 2.00 20% discount in case containing 144. ditto, but without special rubber stopper. Capacity ili. is Sa ae igen pet 2s Mor cn ays sya raln a Mager a tina ines de ats 30 60 Per dozen, in carton of 1 dozen... 1... ee eens 1.25 1.30 20% discount in case containing 144. i Special Rubber Stopper, only, as supplied with above Vaccine Bottle. Perdozen................ .60 Bottle, Water Sample, with patent stopper; 12-ounce capacity. So-called ‘‘Citrate Magnesia”’ NOE ESS se At on tne teti eA Pe cages cca tapos ca na a et oa A a se wat Cw enedecrnu ive Ratan RGA mcs i aetna 15 10% discount in case containing 144. Bottle, Water Sample, wide mouth, with flat ground in stopper, 2 oz. capacity; a turned mould bottle of special shape and high finish, widely used in filtration and health laboratories. Each...... .40 20% discount in gross lots. . , : ditto, but furnished with wheel-cut numbers, one to three figures, inclusive, as desired. Each.. .60 20% discount in gross lots. Bottle, Water Sample, wide mouth, with flat ground in stopper, 2 oz. capacity; an iron mould bottle not so finely finished as the preceding but made in our private mould of a new formula lime glass very superior in stability to the ordinary flint glass mostly used in the manufacture of bottles and, therefore, especially suitable for water samples. Each............................0.045. -20 25% discount in cases containing 3 gross. s : ; ditto, but furnished with wheel-cut numbers, one to three figures, inclusive, as desired. Each.. .40 25% discount in case containing 3 gross. Bottles, Woulff, with two necks. Capacity, ml......... 125 250 500 1000 2000 4000 8000 Path cearsungesaawens 1.25 1.40 1.50 1.90. 3.00 3.75 6.00 ditto, but with bottom tubulation. ‘ Capatitya mln er oo eho pee dae ee tet 500 1000 2000 4000 Bache Scns fdas esa cece de ei eee nee oe Teka 1.80 2.50 3.80 5.00 Bottles, Woulff, with three necks. Capacity; -mlci as ostten tee 250 500 1000 2000 4000 8000 Bigcheese ae tenet 1.60 1.70 2.50 3.50 4.00 6.50 ditto, but with bottom tubulation. Capacity: Wilt. 2 seen sen whey cai Sent ee ea peer tee tha 500 1000 2000 4000 Hach es aa ny ihe een oa eee ctan 2.20 3.30 4.75 5.50 2350. 2352. 2354. 2356. 2357. 2358. 2360. 2361. 2362. 2363. 2364. 2365. 2366. isn i my 2352 | rua { Boxes, of pasteboard, so-called “pill boxes.’’ Covered with fine glazed paper, carmine colored. 3 cou DVAMeter IN Ghese es ees een arn che erate arenes Sina ren mene eae a 1 13 DD Spthinin Cheshse pakeeav ues ved cham iaevan ts suacnante eae Aer me aiat neers) 3 a6 z Per gross, in carton containing 144............ 0.0.0... 0.00 e eee -6U 1.20 1.40 Boxes, of pasteboard, sliding form; covered with fine, white, glazed paper. WOT PG ATC CS ore sass pccrt tes ce stee setiesctnch lace ped ont rapes aiticaent a eiidieueor at tat ne oe eset a oes 24 22 Wald hi, Sia CHES ie pacts d tr es tomesig ss Avion 2 vere cat toca trad Petites ete end See SAA Ni gee Ti Re ereenoen te 11 13 Ae py bhny Wai CH eS eiceescs Sacer strike was m ee Goa aA eR crete ak Oe wie tht ants Niet iy eons neenaraeta ne 3 g Per dozen, in carton containing 36............0. 0. cc cece ee ene eee ene eeee 25 .25 Boxes, of seamless tin, round form. Convenient for samples and specimens. Capacity; Oun CES. catia haseta hs kine altars neh or eR aoe 3 1 2 4 Diameter cin Chess eras Wyle cache aecta am nicte ee oc ce 13 1i 23 3 Height, 7in Chess giskcttet sac ckee Soha, odes acre om ie aoa 4 2 z 13 Pr dozen. seen Aili ies Behe Ata ee eta ented .20 25 -40 .60 10% discount in carton containing.................... 72 "2. 72 48 Box, of seamless tin, deep form with rounded bottom. Approximate capacity 3 ounces; 2,%5 inches diameter by 1;$; inch high over all. Perdozen.............. 000.002 cece cette eee .60 10% discount i in carton containing 36. Box, of seamless tin, tall form, especially recommended for cement samples. Capacity 4 ounces; dimen- sions 23 inches diameter by 1? inches high. Per dozen...................0 000 c eee eeeeeee .65 10% discount in carton containing 36. Box, of turned wood. Convenient for samples and specimens. Capacity 4 ounce, 13 inches diameter by 13 inches high. IRE COZEM aarti lis SUS he a AA n hear ne oe ch ese lteietind deh a eae Lie haan MENA Rane Bede Sala) eleasuarauene ates .35 10% discount in carton containing 48. 20% in carton containing 144. 2363 2364 2361 2366 Brush, of black horsehair; 9 inches long, with wooden handle. For cleaning small cylinders, etc.... .25 10% discount in package containing 12. 20% in lots of 144. Brush, of black bristle, -onical shape, with tuft on end; 12 inches long. For cleaning cylinders, etc. .35 10% discount in package contiining 12. 20% in lots of 144. Brush, of black bristle, conical shape with tufted end and four rows of bristles. For cleaning large cylin- toe JAMS O LCE Be nic cihe ace eRe a ea eas eg mae nia ern LAR eed erat nad Rl OEE eral ees ahah doe -50 % discount in package containing 12. 20% in lots of 144. Brush, of ae bristle; 12 inches long. For cleaning beakers, cylinders, etc...................0-. .27 10% discount in package containing 12. 20% in lots of 144. Brush, of black and white bristle, on wooden handle, with four rows of bristles. For cleaning large jars, 505; BA cee aeed eRe nla PR We GAN PUPL RTECS MORIN Ae vn ews we Ghar PE Boe He a Na ae ge Re Ae ee wld p wee eh ER 45 %, discount in package containing 12. 20% in lots of 144. Brush, of black and white bristle, with two tufts on end for reaching corners of large cylinders, jars, etc. With four rows of bristles................... Ry cies Avetices ch Gnatec una aantea i hint etn oii Gao 50 0% discount in package containing 12. 20% in lots of 144. Brush, for beakers, with long handle of wood........ Brat ee oh ee chal iane s aaa wl set amok aes -40 10% discount in package containing 12. 20% in lots of 144. 86 2370. 2371. 2374. 2375. 2376. 2377. 2378. 2379. 2380. SE) Up eR H. T H O M A § C O M P A N _Y 2376 Brush, ah with pliable end, particularly recommended for convenient cleaning of flasks because of SIVA DC ose sean hash Ona ne ts xls A Euan a ap EAU n nL lle Laren eatin sundaes n ea cae Risse aaa ata ace ana ea ae oe hee 35 10% discount in package containing 12. 20% discount in lots of 144. Brushes, for volumetric flasks, with flexible steel spring enabling the brush to reach every part of the flask: “Total length; nChess 210.2 sett soe oak Oe phate ck cals gcucct ements week 1 8 Por flasks, capaclty smal. is, og eatin esterace si beowa nee hi tes, ange th he albledeveelg os 250 500 1000 De isa escheat ae Sale yale lO nt 8 SLA ater bd oor alte few gee vas AR ee ae ch Oe 37 -40 42 10% discount in carton containing 36. 20% discount in lots of 144. Brushes, of bristle, in wooden handle, flat. Convenient for pasting labels, etc. Width: of bristles, inches... veces esac eet ealles euler 1 13 2 4 ACH cee raters tne, con Senet ort or wore spree Bs, Lad Gees ab es Senn Ege ERE ea 18 -20 .30 -40 10% discount in package containing 12. 20% discount in lots of 144. Brushes, of camel’s hair, flat, with wooden handle. For dusting scale pans. a2 Width of hair, inchesic3 44 ocves es deg shaded Yew cad tae oe aes : 1 13 2 BC Tica atta tinal se eec Me ene ee tenths eth nen each Ma Sen Sc 25 .40 50 -65 20% discount in carton containing........................ 24 24 12 12 Brush, of camel’s hair, round with wooden handle, } inch diameter. For dusting scale pans, etc..... .85 20% discount in carton containing 12. Brush, Camel’s Hair. A split quill brush of convenient size for dusting balance pans and other parts of delicate apparatus. The hairs are about 1} inches long.....................00..00 000000, .60 10% discount in carton containing 12. Brushes, of camel’s hair, bound in quill handle. Length of hair,mm........ 14 18 22 Per dozen ...2 366 3 ei es eb eri eactsl tian Creme ey is Pett meses 1.50 1.68 2.16 20% discount in carton containing....................... 00.2.2 0 ee 72 96 144 Brushes, of camel’s hair, bound in quill, so-called “‘camel hair pencils.” INA TIDOTes ss nieie cee cocoate any ses ee eh eels Ot a oh 3 5 7 ree eae arse eee ae es EN ae Nene See eas ae as en aren eh ana) eae eee Small Medium Large Length of haireminy<.cucte pqseeiwrans en Ree ORE OS 14 16 18 GEA O ZOTAR aA ca RE ee TE ee .20 -40 .55 20% discount in carton containing......................... 36 144 144 Brush;.of bristle; for assay buttons '.c: BABBOCK TRUNNION CUP METAL TUBES RUBBER CUSHION Ri R HION BER CUSHION / t f 'UBBER CUSHIO’ RUBBER CUSHI 3109, 3110, 3111 3057, 3058 3053, 3054, 3055 3109. Trunnion Ring, for 100 ml metal tube, for use on Heads Nos. 3042, 3044 and 3093.............. 50 3110. Metal Tube, with rubber cushion, for 100 ml glass tubes No. 3131........___. Reyne: ... 1.00 3111. Rubber Cushion, for 100 ml metal tube. Perdozen...............0000.00000000000000000 03 1.92 3057. | Babcock Milk Test Trunnion Cup, for 6-inch bottle, with rubber pad; for use on Heads Nos. 3042, 3044, BOOZ an dr0I 3 het jn Mattila Aue ats eke nae ehy yates oo dink Ce ale meted hl her y Nade .80 3058. Rubber Pad, for Babcock Trunnion Cup No. 3057. Perdozen.............. -60 3053. Trunnion Carrier, 3 Place, for Metal Tube No. 3054, for use on Heads Nos. 3042, 3044, 3092 and 3093 1.25 3054. Metal Tube, for Agglutination Tube No. 3128 for Trunnion Carrier No.3053...................... 3055. Rubber Cushion, for Metal Agglutination Tube No. 3054. Perdozen.....__ pase neh ed sie 45 126 3112. 3113. 3058. 3114. 3115. 3116. 2993. 2994. 2996. 2997. 3117. 3004. 3006. 3118. 3119. BABCOCK BOTTLE \ > OL TUBE | | as RING | TRUNNION RING ~~~ BABCOCK BOTTLE AHTCo TRUNNION RING —BABCOCK CUP ' Ae METAL TUBE BAGSCOCK CUP \ | = RUBBER CUSHIUN = _ — RUBBER CUSHION S RUBBER CUSHION 3112, 3113, 3058 3114, 3112, 3058 3115, 3116, 3112 Trunnion Ring, for use with 9-inch Babcock Metal Cup No. 3113, and metal Oil Tube No. 3115, on Heads Nos. 3042, 3044, 3093, and with Babcock metal Cup No. 3114 on Head No. 3092 On] Yes cas eae 55 Babcock Test Metal Cup, for 9-inch bottle, with rubber pad, used with Trunnion Ring No. 3112, for use OneE Ca de NO3 092 ep canons aretha vidio Maree Lk Rae) Otis at dR ee cee aan PG on ee ee 1.05 Rubber Pad, for Babcock Test Metal Cup No. 3113. Perdozen.............................. -60 Babcock Test Metal Cup, slightly longer than No. 3113, for 9-inch bottle, with rubber pad, used with Trunnion Ring No. 3112; for use on Heads Nos. 3042, 3044 and Bet eiunre hans 1.45 Metal Oil Tube, 100 ml, with No. 3116 Rubber Cushion, for use with Trunnion ae No. 3112 on Heads INOS: 30423044 and 30985, crear sad Stee Nap ot ope uh ree Od alate eta a ice nus ieog aie nad anes ne 1.75 Rubber Cushion, for 100 ml Oil Tube No. 3115. Each..... ek ee ene DEpoay ice eee ores -60 =“ || : 2 41 ; | | Na J 2993, 2994 2996, 2997 3004 3006 3118 GLASSWARE AND RUBBER CAPS FOR USE WITH SIZE 1 AND SIZE 2 INTERNATIONAL CENTRIFUGES Glass Tubes, Ungraduated, 15 ml capacity, for use in No. 3051 Metal Tube 50 ml, with No. 3056 Reducing Cap; and in No. 3008 Metal Tube 15 ml. Perdozen.........................00 0.0.0... 1.25 20°; discount in carton containing 144. ditto, but of Pyrex Glass. Perdozen............... eT ee ee eee .... 3.00 206; discount in carton containing 144. Glass Tubes, Graduated, 15 ml capacity; graduated in 1/10ths up to 10 ml and in 1 ml divisions from 19 to 15 ml. For use in No. 3051 Metal Tube 50 ml, with No. 3056 Reducing Cap, and in No. 3008 Metal Mabe: toilet Ba Chics scs ayn caine ie the oe ase ioe eo hese come cL wee at cide Reet aR IL wea <45 10% discount in carton containing 12. 20% discount in case containing 1 gross. ditto; butiot. Pyrex:elassy. (Hachi...« aw 3131, 3132 3133, 3134 3135 3136 2204 3131. Glass Tube, 100 ml capacity, with pourout and round bottom; for use in No. 3110 Metal Tube. Each .25 3132. ditto \ " i. ie ny p oo 3269. 3270. 3272. 3273. 3274. 3276. 3278. 3280. 3282. 8025. 8026. 8027. (ou fio r 4 a = bo nD wm 8025, 8026 Clamp and Extension pit BOE Rod in position on 3280 No. 8024 Support Clamps, Hoffman, for rubber tubing, nickel plated, so-called ‘‘screw compressor.’”’ Dimensions given are for maximum diameter of tubing for which clamp is available. SIZE INCHES! 15a ae Pires ahs a Pee EN naa Phae bn ata Ue meet ess dtomus 2 NES AY, Shyu say CRS 7 Sy f ° 2 na we Slate 10°; discount in lots of 25. Clamps, Hoffman, for rubber tubing, nickel peien with one swinging jaw. For maximum diameter of tubing, inches. . Lite PUishang taints AeA Gh He Soran TB eA CMU rset aia fonts, Gi) ace NA cla eve ook stncth aieeyMaektmtias oc a x fae eee AN ted ake ede ose RLS Joos, 322 22 10°; discount in lots of 25. Clamps, Hoffman, for rubber tubing, nickel Bees with open jaw. For maximum diameter of tubing, a Ico inches... ages . BRU Rep 4 ent RE ieee enieneae, 3 3 BACH ese an valoprari cevel wecale woes OR rea ee conte GR ah dg Secunia ae ar anole mean ana eRe p eae see 22 30 10% discount in lots of 25. Clamps, for rubber tubing. A modification of Hoffman clamp, permitting attachment to rubber tubing without disconnecting apparatus. For tubing up to, inches................... fs 3 HC es eroea hones hes eee wet pata seals eh en Van pees a eas ib agnaciee Se ics Hele shinaG aie ceo .30 ditto, but extra heavy for use on pressure tubing up to l-inch diameter...................... -50 Clamp, for rubber tubing, of brass, nickel-plated, extra heavy, } by 1} inches................... .36 10°7 discount in packages containing 25. Clamp, for rubber tubing. A precision clamp for rubber tubing originally designed for work in physiology. The jaws move exactly parallel throughout their whole length and with great precision, and are so constructed as to make an absolutely airtight clamp on heavy wall rubber tubing. Will take rubber tubing up to 13 mm outside diameter. For the range of rubber tubing intended, this clamp is far superior to the usualforms. Of brass, nickel plated...........0..00. 00.0... 000 2.00005. 1.25 Clamp, Mohr’s Pinchcock, of flat wire, length 23 inches over all................0.0....0002..0.. 12 10° discount in lots of 25. Clamps, Mohr’s Pinchcock, for rubber tubing; of nickel-plated spring wire. Length of clamp, 3 « LETC See a eet estrella Dat alban Ae Dre an ita are t ae tl de ew OA : 2,70 ER Each. eRe a goes ae Mies aR or Une der is cease ei re teh ate rae 45 16 18 10% discount in lots of 25. 15! 4% discount in lots of 100. Clamp, Day’s Pinchcock, Patented, for attaching to or removing from rubber tubing without disconnect- ing the apparatus. Convenient and serviceable, of stout spring brass wire, plated white. a De inches* fOr tubing UP CO:6 IN CMS rece necro meses ees doh Sea eee pp ete gas e78 y larry anes metro Clamp, Right Angle, as used with No. 8024 Support ................ eb aSe nck tee Moe ete Jo... 1.00 Extension Rod only, as used with No. 8025 Clamp.................. saaendeitire See acre ae nthe -70 Clamp, Slow Motion, specially designed for use with recording apparatus, etc. Suitable for use on No. 8024 corso ther SuppOrtisvenscnpcles ste 5s Meche SGA ts Nake Shakin Rl? cs BR ARN Narco ulcer ce 4.10 3286. Clamp, of wood, for holding wire connections on 8 mm support...............00 000 e eee eee 50 3287. Clamp, nickel plated, for attachment to 6 mm support rod, with wing nut adjustment........... 2.30 3288. Clamps, of spring brass, heavily nickel plated, for thermometers, burettes, conductivity and electrode vessels, etc. The same spring which clamps the articles to be held in a vertical position serves also to clamp the support, thus obviating the use of any screws; will take articles from 10 to 25 mm diameter. To fit: support rod,mmdiameétér..s a. ka adage nner eaeonee es 6 8 10 12 Poa Chis Sag Se oe ae eee a std hee ora Ra MS ener uC ace sh eae a Dee 80 -80 -80 .80 3289. ditto, but larger and heavier; particularly designed for calomel and hydrogen electrode vessels, etc. Will take articles from 20 to 45 mm diameter. To fit support rod, mm diameter.......................0-5.- 6 8 10 12) GACH aire Oks ae Ren ee hcl Ab reat icete kg oe tie ps Mw abe ieee niet AR 1.00 1.00 1.00 1.00 3290. Extension Holder, consisting of a 6 mm nickel-plated rod, bent at right angle for holding either No. 3287 or No. 3288 Clamps. Tun VOLO C VANS tcsn ks oP kee yes ak ett harper ue ae Cars hee EA OE EN Le eRe pated feb 1 2 BCH ap ccerretes eee shee sc ea tops DA GE beard ta heelete eis is ak eaaee tert Me cet ePe de eee atte dee pine oes eee emg -45 45 3291. Extension Holder, consisting of a straight, nickel-plated rod, 6 mm diameter and 150 mm long..... 60 3292. Clamp Holder, nickel plated, for use in attaching a 6 mm extension rod toa 6 mm supportrod...... 40 3293. Clamp, nickel plated, for use with a 6 mm extension holder such as No. 3291 and No. 3292 clamp on a support for conductivity cells for attachment to the side of a constant temperature bath when cells are ammersed Incthe-bathn cn. 45 2:0 = wc a cece aad bis Saud ees ao ae een ave aie geelele 3.40 Packages of Laboratory Apparatus in our shipping room destined to ten foreign countries, showing our method of packing and marking export cases 136 A R T H U_ R Fi a ET eO™ OM « 3400 BLOOD DILUTING PIPETTES FOR HAEMACYTOMETERS. These pipettes are made in general accord with the original Thoma design. The Bureau of Standards on May 1, 1917, established a tolerance for the principal interval of the pipettes of + 3%, and all our pipettes are guaranteed to be within this tolerance. The Bureau of Standards no longer supplies a certificate for those sent to them for test stating the exact error, as this error has been found in practice to be negligible. The Bureau engraves all pipettes which come within their specifications and within their tolerances with the mark U. S. 1920, thus: which certifies to the user that the pipette is within the Bureau’s specifications in every way, and that the actual error is negli- gible. All our pipettes are regularly supplied with a suitable piece of rubber (us) tubing and a bone mouth- piece. 3390. Blood Diluting Pipette, Thoma, as above described, diluting 1 to 100 and 1 to 200, for red corpuscles 2.00 3391. ditto, but tested by the Bureau of Standards and engraved with official mark of certification... 3.25 3392. Blood Diluting Pipette, Thoma, as above described, diluting 1 to 10 and 1 to 20, for white corpuscles 2.00 3393. ditto, but tested by the Bureau of Standards and engraved with official mark of certification... 3.25 3396. Mouthpiece, only, of bone, for above diluting pipettes...................... 0. 10 8848. Rubber Tubing, 3 mm bore, 1; mm wall, for use with above diluting pipettes. Per foot........ 10 3400. Blood Diluting Pipette, Rieder, for diluting 1 to 20; with rubber tube and mouthpiece........... 3.00 3401. Blood Diluting Pipette, Miescher, for diluting 1 to 100, 1 to 150, and 1 to 200; with rubber tube and MOUtHPICCO sre tsar ees oegnnae De FeRAM ore MURMUR Ch Mee geht Aa 4.00 3402. Blood Diluting Pipette, Miescher, for diluting 1 to 200, 1 to 300, and 1 to 400; with rubber tube and TM OUCH PIECE: systeviesd. ea sha eureeces earned gee otic oat eee ORG. Men Ag AGN oeh yhomals con ead teaelochely 4.00 3410. Cases, of leather, velvet lined, for Counting Chambers only. To fit Counting Chamber........... Levy Single Levy Double Hausser Interchangeable Bachteticcs. Hee ne es 1.50 1.50 1.50 3411. Cases, of leather, velvet lined, for complete Haemacytometers. To fit Counting Chamber......... . Levy Single Levy Double Hausser Interchangeable Bagels ke a ee Pee a 5.00 5.00 5.00 141 sees Sees} \ So os Ss oS it (RX Ha : NN ai 3453 Plain Opal 3441 DARE HAEMOGLOBINOMETER. The application of this instrument depends upon the principle that the color of a thin film of undiluted blood, illuminated by a standard light, may be compared with a graduated color scale. It has the advantage over other methods employed for a similar purpose, that while but_a small drop of fluid is needed for its application, this consists of pure blood undiluted with artificial serum. |The tech- nique and possible errors of measuring, dilution and color diffusion are thereby entirely eliminated. ay Leukocytosis, which is a frequent source of error in haemoglobin estimations, imparting as it does a turbidity to mixtures of blood and water, becomes invisible when viewed by transmitted light against white background. The epaettys due to increase in the number of leukocytes, is imperceptible and only the red color of the haemoglobin is visible. Furthermore, the shades of color to be compared are very decided, even in blood markedly deficient in haemoglobin, and this facilitates accurate comparison. Besides the colorimetric principle there is an element of density, due to concentration of coloring matter present in the blood film, that renders the definition of shade more pronounced, giving a wider range between points indicated by the scale, insures more uniform comparison and greatly reduces the ‘‘ personal equation”’ of estimation existing in different individuals. The technique of the examination consists in collecting the blood and measuring the percentage of hae- moglobin, by turning the color scale until its color is identical with the blood contained in the pipette, brought close beside it. The indicated percentage is then read off, the plane surfaces of the blood pipette are washed and replaced in the pipette clamp. The entire examination can be completed in two minutes. The percentage scale is invisible while making comparisons and cannot be forced. A dark room is unnecessary, as the yellow light employed for illumination absorbs the violet rays of the solar spectrum. A recent improvement consists of an electric illuminating device to replace the candle used on the original form. The small electric light can be operated on any 110-volt circuit with suitable resistance which is furnished with it, or by means of a primary battery attached to the instrument in the form of a handle, as shown in illus- tration. A contact key is supplied so that the illumination only occurs through pressure of the key, thereby greatly extending the life of the primary battery. In both electric devices the bulb is entirely enclosed, absolutely excluding daylight except where the eye covers the tube. 3440. Haemoglobinometer, Dare, as above described, for candle illumination only. In leather case..... 30.00 3441. ditto, but for electric illumination, operating on 110-volt circuit. With resistance, connecting cord LTT GURU a are erreurs caotecicat irae ek Ae tose eM end eles ite shee ces VR Batt totaal pkey abet ose 39.00 3442. ditto, but for electric illumination from primary battery supplied in the handle _... 39.00 3443. Incandescent Lamp Bulb, only, for Dare Haemoglobinometer........... cette: ea sieee 50 3444. Battery, only, for insertion in handle.................... bclines Sages See ; 4 -60 3445. Automatic Collecting Pipette, only, for Dare Haemoglobinometer........ ; ae 5 ewe web 3446. Opal Glass, only, for automatic collecting pipette............... é A rth egies thes Be 1.00 3447. Plain Glass, only, for automatic collecting pipette... 0.0.00. ee -50 3448. Haemometer, Sahli, for determining the percentage of haemoglobin in the blood. A measured quantity of blood is mixed with ten times the quantity of dilute hydrochloric acid of a definite concentration. The mixture is then poured into a graduated glass tube and diluted with distilled water until it is of the same color as the tinted tube provided, when the percentage is read off the scale. Accurate to within 5% or 10%. With latest modification for use either by day or night............... 8.00 3449. Graduated Pipette, only, 20 cmm, for Sahli Haemometer................... eased h MAN ce ... 1.50 3450. Graduated Tube, only, for SahliHaemometer......... 5 Bede ade area ; : .... 1.00 3451. Dropping Pipette, plain, for Sahli Haemometer. ; ay a St horns easels mere: ee!) 3452. Color Tube, only, for Sahli Haemometer Dee nro Teer on eno vekvteniey AEbO 3453. Haemoglobin Scale, Tallquist. A color scale of ten tints, ranging from 10% to 100%, bound in book form, pocket size, complete with 50 sheets of standard filter paper sufficient for 150 tests, and directions POT USC Moira tek ai teat ok Reece tes cs a 2 en gel eh eine tee nat rep tary a elas Re ac due hfe acon ac 1.75 3449 3466 Cross-section of Boggs Coagulometer - TRENT TTT gy 3! i7' bs eb bk lo Se weer To oe i a 2 ( 3468 A B 3471 3472 C 3473 w 3460. Haemoglobin Attachment, Newcomer, for the clinical estimation of oxy-haemoglobin in the blood in Haldane scale percentages, consisting of a plate of a certain high transmission yellow glass 22 mm square, accurately ground and polished, for insertion in Duboscq Colorimeters, either original French or Bausch & Lomb make, in the light path of one of the cells—at the top of the plunger. This attachment may also be used in the Bock-Benedict Colorimeter, placing it below the mirror FM (see illustration on page 159). The light fields should first be balanced with water in the cup C and the cell S removed. Each glass plate is calibrated and engraved with exact thickness and a correction table is furnished with each attachment. Readings should be taken through Daylite glass, such as is provided in our Colorimetry Lamp No. 3746. The Mazda ‘“‘Daylite’’ bulbs provide a fairly satisfactory and inexpensive illumination for this purpose. See Dr. H.S. Newcomer, Journal of Biological Chemistry, March, 1919... 0000 occ ccc cece cece ees 3.50 3449. Pipette, Capillary, graduated at 20 cubic millimeter, for diluting blood in the use of Newcomer Haemoglobin: Attachments 25... Asc geen nt a conanck oie lncsre inerobud cine a eat aed rence re kee gh 1.50 COAGULATION TIME, SURFACE TENSION AND VISCOSITY OF THE BLOOD. The physio- logical and clinical significance of these @haracteristics of the blood and other body fluids have assumed more importance as a result of recent investigations. The Boggs Coagulometer, a modification of the original form of Russell and Brodie, is perhaps the most convenient method for determination of coagulation time. In this instrument, the coagulation time is determined by the observation of the movement of the blood corpuscles under a low power of the microscope while subjected to a current of air in a moist chamber. In common with all other methods that involve getting the blood from puncture of the skin, this method is subject to errors because of contact of the blood with tissue juices. A more reliable method for determining coagulation time (Howell’s prothrombin time) is that for the clotting time of recalcified oxalated plasma, which requires no special apparatus. In the Hess Viscosimeter, we offer a reasonably accurate method for the clinical determination of blood viscosity, utilizing only a small amount of fluid. The measuring tubes are conveniently mounted on a graduated opal glass plate, which carries also a thermometer. A new laboratory form has recently been announced, by which accurate temperature control can be obtained and more accurate readings taken. Both models of this in- strument are tested in Prof. Hess’ laboratory before shipment, so that results with different instruments are al- ways on a comparable basis. See Austrian, Bulletin of Johns Hopkins Hospital, XXII: 9, 1911, and Matsuo, Deutsch. Arch. klin. Med., CVI, p. 433, 1912. For the determination of surface tension of blood and similar fluids by the number of drops formed by a given volume in a given time, we offer the Traube Stalagmometer. It has been used for the so-called ‘‘small drop reaction” in the study of typhoid vaccines, and similar investigations in immunity. See Biochem. z. Marz, 1910, Miuinch. med. W., 5762, 1910, and Journal of the American Medical Association, May 28th, 1910. For an apparatus for the more precise determination of surface tension of fluids, see the du Noiiy Surface Tension Apparatus, page 568. 3466. Coagulometer, Brodie-Russell-Boggs, for determining the coagulation time of the blood on the stage of the microscope. With rubber bulb. Incase ......................................... 15.00 3468. Viscosimeter, Hess, Clinical Model, as above described, for determining the viscosity of the blood, colloidal and other solutions. Complete in case with reserve tubes, two small bottles for distilled water and ammonia, rubber bulb and directions for use........................... .. 15.00 3469. ditto, Laboratory Model. A larger apparatus operating on the same principle but with water jacket for: temperature*control, Cbs 66 .cciae wn wed race eon aaa eae bee be Sieh Reta .. 30.00 3470. Stalagmometer, Traube, as above described, for determining the surface tension of blood and other fluids, consisting of three accurately calibrated glass tubes, being one each for small quantities of thin liquids, for large quantities of thin liquids, and one specially designed for blood and other MOLE: VISCOUS SOlUtIONSs: ALN CASC isis 2-28 lee nao goes ee on ee nagar el Ws a eels 9 eh .. 30.00 3471. Stalagmometer Tube ‘‘A”’ for small quantities of thin liquids, as furnished in above outfit. In case 13.50 3472. ditto “B”’ for large quantities of thin liquids. In case................. She AS) BNE tea ah ANNs 13.50 3473. “«< «C” * blood and other viscous solutions. In case.... ©. ........... 0 ...04.. Wunetae Oo eDO. 143 AUR or Oe ER Fe T H O M A S Cc O M P A N Y 3480 3484 3476. Alkali Reserve Outfit for Blood Plasma, Marriott, consisting of a set of nine sealed insoluble glass tubes containing standardized phosphate solutions colored with phenolsulphonephthalein, numbered as follows: 7.0, 7.2, 7.4, 7.6, 7.8, 8.0, 8.2, 8.4, 8.6; also one insoluble dialyzing tube, one tube for making sacs, one tube for aeration, one capillary nozzle tube and 100 ml of phenolsulphonephthalein in 0.8% sodium chloride indicator solution. See Dr. W. McKim Marriott, The Archives of Internal Medicine, June, 1916. Complete, with pamphlet of directions.......................... 6.50 Directions for Use of Marriott Alkali Reserve Outfit. Exactly 0.5 ml of the specimen serum is dialyzed seven minutes through a collodion sac into 2 ml of the indicator solution contained in the small dialyzing tube. The dialysate is trans- ferred to the long tube and a current of air passed through it for three minutes by means of the capillary tube attached to the atomizer bulb. The air current should be as rapid as possible without blowing the liquid out of the tube. The color in the tube is then compared with the standard color tubes, interpolating when necessary. Readings should be made at temperatures between 20° and 25° C. 3478. Alveolar Air Testing Outfit, Marriott, consisting of one set of eight insoluble glass tubes with standardized phosphate solutions colored with phenolsulphonephthalein and numbered as follows: 10, 15, 20, 25, 30, 35, 40 and 45 mm; also one long insoluble glass test tube, one insoluble glass capillary nozzle, one metallic comparison box arranged to hold the specimen and two color tubes, one 1000 ml rubber bag, one rubber bulb, one pinchcock, one glass mouthpiece, and 100 ml of standardized sodium bicarbonate indicator solution. See Dr. W. McKim Marriott, The Journal of the American Medical Association, May 20, 1916. Complete, with pamphlet of directions.............. 8.50 Directions for Use of Marriott Alveolar Air Testing Outfit. Fill the test tube one-fourth full with standard bicar- bonate indicator solution. Then place the capillary nozzle tube into the outlet tube of the bag containing the alveolar air and, by releasing the pinchcock, allow the air to pass rapidly through the solution in the test tube for about one minute or until no further color changes occur. The tube is then stoppered and the color immediately compared with that of the standard solutions most nearly approaching its color on either side. Examination should be made, if possible, at temperatures from 20° to 25° C. If the room temperature is above or below this, the specimen should be immersed in water at about 25° C, while being saturated with the gas under examination. 3480. Acidosis Combination Outfit, Marriott, consisting of Alkali Reserve Outfit for Blood Plasma, No. 3476, and Alveolar Air CO, Testing Outfit, No. 3478; in one case and with but one metallic comparison DOK sey ety R AS atl 3 he Ka roa dae red Ba cere Seen aera ae Olean 5 Vaan ite yy knee Een eM, cal i ak ca 12.50 3484. Colorimetric Outfit for Determining H-ion Concentration of the Blood, Levy, Rowntree and Marriott, consisting of a series of standard colored liquids for comparison with the specimen contained in sealed glass tubes and marked as follows: 6.6, 6.8, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 8.0, 8.2, 8.4, 8.6. That they may be quickly selected, they are placed in a wooden holder, which, together with the examination box, is carried in a polished wood case 13 by 4 by 113 inches. The stability of the colors is believed to be reasonably permanent, but if there is any evidence of fading the appara- tus should be returned for examination and adjustment after six months. The glass tubing of which the ampoules are made is non-soluble and especially selected as to uniformity of diameter. See Drs. R. L. Levy, L. G. Rowntree and W. McKim Marriott, The Archives of Internal Medicine, SOMLCM DERE LO LO eae tht conta nhl Si dW ape telet gran arn De nO Oe Wi ac DS ot ae gE cpa ew dy A vere 8.50 Directions for Use of Levy-Rowntree-Marriott Colorimetric Outfit for Determining H-ion Concentrations of the Blood. Comparison of Tubes with Standards. For this a good light (natural or artificial) and the white glass back- ground of the examination box are requisites. Readings must be made immediately after the dialyzation. The two tubes most nearly approximating the color of the specimen are selected and one placed on each side of the specimen. These are critically inspected against the white background. If the relative position of the tubes is changed the dif- ferences in the colors are made more apparent at times. It must be borne in mind that in comparing the dialysate with the standard colors, it is the matching of the quality, not the intensity of color, as in ordinary colorimetry. 144 ne aR EI. T H O M AS Cc O M P A N _ Y 3486. 3490. 3491. 3492. 3493. 3494, 3495. 3496. 3500 3502 3500. 3502. 3504. 3505. 3508. 3510. APS Peeled 3490 Colorimeter, Dunning, for estimating the quantity of phenolsulphonephthalein excreted when applying the Rowntree and Geraghty Renal Functional test. Complete in polished wooden case....... 6.00 Sterile Ampoules of Phenolsulphonephthalein, 10 in a box...... 0.0.00... ccc ccc cee eee eee 1.25 Micro-Saccharimeter, Eppstein, for the rapid clinical determination of sugar in the blood. A small scale adaptation of the method of Lewis and Benedict, using small quantities, 7. ¢., 0.2 ml, of blood, and obviating the use of an expensive colorimeter. The outfit consists of color standards A and B, accurately graduated color tube for the unknown, support with opaque glass for the color tubes, one pipette 1 ml graduated in 1/10ths, one pipette graduated at 0.1 and 0.2 ml, one tube graduated at 1 ml and 2.5 ml, two boiling tubes with suitable holder, filtering funnel, dropper, and set of three solutions: Picric Acid, Sodium Carbonate and Sodium Fluoride. Comipletesin:caser. sien teen ioc aaeaht Uccohe tip katty goat sent ait Shoah Oe al a atah ee Ay ong a Aiea uae aE 16.00 Color Standardt Ayre coy siete el eek a dln Lae reals cee! Bim AW bal GaN a pleat Goo IG ced weil tec ce a gas as ae ass 1.25 ColorStandardi Bisse ecrser ons ea ee ate emineteks Wine en eam sa ene eth Picea ase er eto 1.25 Graduated Color Tube, accurately calibrated. ... 2.0.0.0... 000 cee 1.25 Boiling Bub es rte eRe sor ch nhemciae Mtiren ete eI Sect ace ch ico atom aR AE pea eee Ae ae eA neces cern aerate -10 Tube; graduated ati mand! 253ml sie oe iets ae peed Wien Be cer aee a ah rcetenuenty gluvash SoA eel A 2g : -40 Pipette, graduated at 0.1 ml and 0.2 ml, with rubber tube and mouthpiece.................. pink 75 TT OGRAMMES ° Tope 2 eS 90:3) AuT.C On 3503 3510 Albuminometer, for the quantitative determination of albumen in urine by the Esbach or Pfeifter method, consisting of a graduated tube with rubber stopper and removable white enameled base. In carton WICH CUPECEIOTIS oe x5 vy a peusen tre ache, Bente se eee com er mn dei ee eles elib Ma Bd Soon, Ry 75 Acidometer, for urine analysis, graduated to read directly in percentage of acidity (Na,,OH) as follows: 5 ml and 10 ml from 10 ml upwards at intervals of 2% to 100% for NaOH solution. With white enameled base, in carton with directions.... 0.0.0... 2 eee 75 Fermentation Saccharometer, Einhorn. An improved design with filling arm of cylindrical construction, making the filling of the tube easier than in the older models. The graduation is to 75% of sugar with the total range of 1%. Put up in set consisting of two saccharometers, one test tube grad- uated to 10 ml, and two white enamel bases. In carton with directions................... 2225 Graduated Test Tube, only, for Einhorn Fermentation Saccharometer.......................0.. 15 Indicanometer, for testing for the presence of indican in urine by Obermayer’s method. For accuracy in determining the degree of color in the reaction, a white background is provided on the tube. In carton; with white enameled base and directions................ 2.0... epee eee eee oy ol Ureometer, Doremus-Hinds. A new design permitting rapid cleaning and filling. The bulb has been replaced by a long filling arm set at such an angle that when filled and inclined until the long arm is horizontal the fluid readily flows into and completely fills same without manipulation to displace the air or avoid spilling. Graduated to read to 0.03 gram in 0.001 gram of urea to the cubic centi- meter of urine. The small urine arm is graduated in 1/10 ml to 2 ml. In carton; with white enameled base'and directions... 4... usinseee el aha yeas Boe ee eRe SUS 2.75 NAN 3543 3532 3530 3540 3512. Urinometer, Squibb, reading from 1.000 to 1.600; length 120 mm. These urinometers are mercury bal- anced and individually calibrated with hand-written scales. They are specially made for us and are much more accurate than the ordinary instrument sold under this desienatle: In case; with cylinder, but without thermometer...... PRPS hay Mirae Dae S : Rodent hs enn taeda iee te 1.10 3513. Hydrometer, only, for use with Squibb Urinometer. : ua an mae nn ei -80 3514. Cylinder, only, for use with Squibb Urinometer..............020 00000 ee .30 3515. Thermometer, 5 inches long, engraved on stem, range 32° to 110° F, in 1° divisions, for use with Squibb NIFINOMECE Ry 2 oe seks nd in is al REE welt oa pork a Raker aslhs aaa drs Py etl, Ul Rad oR lh, hae anne 1.00 3516. ditto, but range-0" to:50° Cy ini divisions: 5 eok 2c he eae Oe Wines ee ee eA eh 1.00 3518. Urinometer, Vogel, for the accurate determination of specific gravity of urine, consisting of two spindles approximately 43 inches long, graduated respectively from 1.000 to 1.025 and from 1.025 to 1.050. These instruments are individually calibrated and ee with hand-written scale. With grad- Uatedseylind Grits wr. CNAs Meee ween aust nal UNRe RRP ca as Spek? Gels bade wea aN AB CORN ARI Ear ae tencee 3. oe 3514. Cylinder, only, as supplied with Vogel Urinometer.... . ; ceri ohies © cee hae een ed here De eden dey 3519. Spindles, only, as supplied with Vogel Urinometer. Graduated ..... 1.000 to 1.025 1.025 to 1. 660 EAC Tay eee cee earn TUN AA cet ORS oN pe 1.30 1.30 SPECIAL APPARATUS FOR THE NEWER METHODS OF BLOOD AND URINE CHEMISTRY after Folin, Marshall, Van Slyke and Cullen, Myers and Bailey, Lewis and Benedict and others. The special apparatus as developed by Dr. Folin and his associates, and as first described in Journal of Biological Chemistry, XI, 5, (June) 1912, and subsequent articles, is listed below. 35008 SGlass: rap for Amm Onis. 2.252 Seaey Bue lh athe fon do eens SA a es a KTS, As HP Aa tata eens -70 3531. Fume Absorption Tube, furnished straight for bending at desired angle in the laboratory............. 75 3532. Connecting Tube, for use with Fume Absorption Tubes. Numberof arms...... 4 5 6 FG a ee ag eu eg cos td ee ea the Se ders ee ee ~ LAS 1.50 1.75 3534. Condenser Tube for urea, 250x15mm............00 0000000 ccc tence neneeaee 20 3536. Ammonia Absorption Tube, Folin, 265 mm long by 8 mm diameter, with one end sealed and perforated with small holes. See Otto Folin and Chester J. Farmer, Journal of Bealoaieal Chenvielrys 21, oe (June) £912. occas ca 3537. Ammonia Apparatus, Folin, eeinicte: eee of dacciat Reese iaicanion Tube Ne: 3538, Se drying tube, bottle, connecting tube and rubber stoppers............0. 0000.0 cc cece eee eeee 3.25 3538. Ammonia Absorption Tube, Folin, consisting of a glass tube 480 mm long bent at right angle 100 mm from top, with lower end sealed and perforated with small holes and with perforated bell sealed OTN es Aired th enc ome asian tc arc at nines A CPA chek esta tan 38 Mirae el Meta acts it ae DO Nant Aer Be hon acts te Pe Sah Ad AEE 1.50 3540. Temperature Bulb, filled with mercury chlorideiodide... oo en .50 3542. Urea Bulb, Folin, for determination of urea... 0... eens 1.50 3543. Urea Apparatus, Folin, complete, consisting of Folin Urea Bulb, flask and rubber stopper............ 2.00 146 SS} ‘ov LAY = 8200. 8201. 8202. 8204. 3550. 3552. 3554, 3555. 9448. 3556. 3558. 3560. 3562. RTE r= | | | “4 ml | i L_25 4 | vq i | —i2.5 8200 8204 3550 3552-3554 3558 3560 3562 Pipettes, Ostwald-Folin. Capacity indicated is from tip to mark, and, as in other volume or transfer pipettes, is to deliver. These pipettes are adjusted within a tolerance + 1/10 of 1%, when volume 1s adjusted by the methods of the Bureau of Standards. As used in Folin’s methods for the deter- mination of total nitrogen, urea and ammonia in urine; Van Slyke’s method for the determination of carbon dioxide and carbonates in the blood and other solutions; for the determination of sugar in the blood iY the Lewis-Benedict method, in addition to a great variety of other uses. Lovde livers aman ateat) sey esi adn ek eee a 1 2 3 5 10 7 ia Gls ketone Wa a eeu etd ee cas .80 .85 .90 1.10 1.30 ditto, but graduated to contain, ml.......... ; 1 2 3 5 10 j AACH hos ob AA Ge Bie Aye Ogle cael On Game nal cele .80 .85 .90 1.10 1.30 ditto, but without graduation, or adjustment for volume, i. e., for calibration in the laboratory. Suitable for capacities,ml....................... 1 2 3 5 10 Ba We i-oss Sanceshn canis ees dia ran art aytad a enh einaidentes -40 45 -50 -60 -70 Pipette, Folin and Wu, 15 ml capacity, graduated from long tip in 1 ml divisions, for use in the preparation of protein-free blood filtrates. See O. Folin and H. Wu, Journal of f Biological Seen 38: 81 CVE VAT DRO ctor ak ae Mea Nee PIN re eA gt A eh ey os eC ont Na eee cient Ae toe Re edo ua Manis ote 50 Digestion Tube, Folin, for use in the micro- eWGeldahl Mosciiencs of load filtraten! in small quantities in the determination of non-protein nitrogen in the blood; also used for the determination of urea in the blood by means of urease and aeration and by the method of autoclave decomposition. Of heavy Pyrex glass with graduations at 35 and 50 ml. The graduation provides for the convenient Ness- lerization in the Cescrae tube. See O. Folin and H. Wu, Journal of pee ee 38: 87 (May) 1919.. eae, : 75 Receiving Tube, Folin, for he deicnnieneen ae urea and urease Dae ctetant and distillation ie the micro-Kjeldahl method. Medium heavy wall, without lip, with graduation at 12.5and25ml. See O. Folin and H. Wu, Journal of Biological Chemistry, 38 : 87 (May) 1919; also used as an amino acid:tube-:inFolin’snewer method. 7.% gives va alas cen seeped Beech dy Man concede peri re eee ees .30 Blood Sugar Tube, Folin, improved in accordance with author’s latest specifications; graduated to 25 ml and with the bulb of such capacity that the surface of the alkaline mixture of sugar in copper falls on the lower half of the parallel constriction. Also used for the determination of creatine plus creatinine. See O. Folin and H. Wu, Journal of Biological Chemistry, L882: Mt GOON os ws cas -60 ditto, but without graduation mark at 25 ml, i.e., for calibration in the laboratory. . : bons apes GAO Test Tube, Pyrex Glass, medium wall, with slight lip, size200x 25mm. Perl0................... 2.50 Blood Sugar Tube, Myers-Bailey, similar to No. 3560, but with dimensions 200 x 13 mm, and graduated at 3, 4, 10, 15 and 20 ml. See Myers and Bailey, Journal of Biological Chemistry, 24 : 147, (1916), and Victor C. Myers, Journal of Laboratory and Clinical Medicine, V : 559, (1920).......... .50 Blood Sugar Tube, Lewis-Benedict, graduated at 12.5 and 25 ml, for use in sugar determination. Of resistance glass with heavy wall and slight lip; dimensions 160 x25mm................0.04 .50 10% discount in carton containing 12. Blood Sugar Tube, Gradwohl-Blaivas, graduated at 1, 4, 10, 15 and 20 ml, for determination of sugar in blood. Of resistance glass with heavy wall but without lip; dimensions 150x18mm........... 50 10% discount in carton containing 12. Distilling Tube, Watson and White, for use in distilling over ammonia in the Folin and Wu method for determination of urea in the blood. The large bubbles of foam, in passing through the numerous small holes, are broken up and the bulb in the tube further safeguards any possibility of liquid being carried over into the receiver. See Thomas Watson and H. L. White, The Journal of Biological ChEMistTy Lb 8 (PCOTUOTY Ys LOOT kai ea Roe pa pecan pital we gy eg Ne MERA AON .. 1.50 200= 26mm 8577 3579 3566. Apparatus for the Determination of Urea in the Blood, Marshall. Complete outfit as shown in the illus- tration consists of two calcium chloride tubes, two Erlenmeyer flasks, two cylinders, one gas washing bottle, two rubber stoppers to fit cylinders, one Chapman filter pump, three special Folin tubes with perforations in bulb, three glass bulb connecting tubes, tubes for connecting flasks and tubes to reach to the bottom of the cylinders with necessary hose, etc. See Journal of Biological Chemistry, XV, No. 3, September, 1913. Complete outfit..................00. 00 cee eee 9.75 3567. Folin Tube, with perforated bulb, for above ........ 00... ccc cece ccc ccc ccc v bbb v ere beees 50 3568. Bulb Connecting Tube, for above. ... 0.0.00... 0c ccc ccc beet c tte e ete eeteeeeey 40 3569. Connecting Tube, short, for connecting flasks, formaboves 6%. iki cee eB ee id wg Sanit wantin ees 10 3570. Connecting Tube, long, to reach bottom of cylinders, for above................ 0000 ccc ee eee ee ee 10 UREA APPARATUS, VAN SLYKE AND CULLEN, for four simultaneous determinations of urea; a modification of Marshall’s enzyme method with Folin’s aeration technique which, with the use of a permanent preparation of urease, permits the completion of a series of four analyses in about thirty minutes. Suitable for use in the determination of urea in urine, blood, spinal fluid and tissue extracts and also for the determination of ammonia nitrogen alone in the urine. See Van Slyke and Cullen, Journal of Biological Chemistry, 19 : 211, (Oct.) 1914. Consisting of a wooden block with four pairs of tubes and one extra tube at the end for dilute acid and which serves as a wash bottle to prevent the entrance of atmospheric ammonia into the system during aera- tion. Each tube is fitted with two-hole rubber stopper, inlet and outlet aeration tubes and with the necessary tubing for connection in series. 3576. Urea Apparatus, Van Slyke and Cullen, as above described, complete with glassware, rubber stoppers and rubber tubing suitable for connection to filter pump, or other sources of suction, but without ACETS PUM D lala eager uate iret anne oNe oy et fave saint at neha ect Akon oo eh Bai BRN nee sats 12.00 3577. Urea Tube, only, 200 x 26 mm inside dimensions. Takes a two-hole rubber stopper size No.6. Without SCOPPEM OF ACTALIOM HUD ES cacao. ene asue nen coer ete cole da aire = cae Seed shea ie etn ed ed hat sok staked ate ean -30 3578. Outlet Aeration Tube, only, 150 mm long with 15 mm bulb in center..............--0000 2-2 eee .30 3579. Inlet Aeration Tube, only, 300 mm long, 6 mm outside diameter, with a bulb at lower end 10 mm diameter, filled withismall perforations-ys.sc'eon eee fatale oe og, God Wesabe ae etd en a ea a .30 SIS). “Wood eniBLOcCk onl yasiics aaa re erence Natit nce tens, Cele bide ewer ovate, Aol Hetecapeleadeeaert Nee 2.00 5286. Filter Pump, of brass, 44 inches long, suitable for use with Van Slyke and Cullen Urea Apparatus..... 1.80 5288. Coupling, for above Filter Pump, } inch, with thread for attachment to ordinary faucet.......... .35 Urease, Squibb, in soluble tablets, 0.1 gram each; for the rapid determination of urea in urine, blood, spinal fluid or other body tissues. This is the soluble enzyme of the Jack Bean (Canavalia ensiformis) and converts urea quantitatively into ammonium carbonate by its own enzymatic activity without the aid of other agents. See J. G. Mateer and E. K. Marshall, Journal of Biological Chemistry, June, 1916. Recommended for use with No. 3576 Urea Apparatus. Per 10 grm. cork-stoppered bottle................................2.- 42. 1.50 Urease, Dunning, for the estimation of urea in urine and blood. Estimations of urea in urine are quickly and accurately made by titrating the ammonium carbonate formed in the original fluid without aerating; aeration is necessary for blood. Marketed only in 25 mg tablets. Per box of 40 tablets References for use of Van Slyke Blood Gas Apparatus. For determination of CO. in plasma or whole blood as a test for acidosis, see Van Slyke and Cullen, Journal of Biological Chemistry, 30 : 289, 1917. For determination of the venous oxygen to detect retarded circulation, see Lundsgaard, Journal of Biological Chemistry, 33 :133, 1918; Journal of Experimental Medicine, 27 :179, 1918; Stadie, Journal of Experimental Medicine, 30: 215, 1919. For determination of the oxygen capacity of the blood as the most accurate means for estimating haemoglobin, see Van Slyke, Journal of Biological Chemistry, 33 :127, 1918. For preparation of standardized blood solutions to be used as standards in colori- metric methods for haemoglobin determination, see Palmer, Journal of Biological Chem- istry, 33 7119, 1918 ; Cohen and Smith. Journal of Biological Chemistry, 39 : 489, 1919. For determination of carbon monoxide in carbon monoxide poisoning, see Van Slyke and Salvesen, Journal of Biological Chemistry, 40 : 103, 1919. For estimation of the blood volume by Haldane’s carbon monoxide method, see Salvesen, Journal of Biological Chemistry, 40 : 109, 1919. BLOOD GAS APPARATUS, VAN SLYKE, for the Determination of Carbon Dioxide, Carbonates, Carbon Monoxide and Oxygen, and Other Gases in the Blood and Other Solutions. The concentration of the plasma bicarbonate affords the most direct and certain warning of conditions of acidosis and can be accurately determined with this apparatus. An accurate determination of any of the blood gases requires only 2 ml of blood and may be completed in a few minutes. See Journal of Biological Chemistry, 30 : 347, 1917. 3590. Blood Gas Apparatus, Van Slyke, complete as per illustration which shows the author’s working arrange- ment, including support, clamps, rings, rubber tubing, leveling bulb, thistle tube, etc. The author’s technique requires the use of one No. 5619 separatory funnel, 250 ml, two Ostwald-Folin Pipettes, 1 ml, and approximately three pounds of mercury. These, however, are not included in the out- FG sccez ne cae hdies bt BAN Saye ey Nott tat enna ed ook gene nae te AIibs sarah tain Ail antag aa ate alg, 21.50 3591. Blood Gas Apparatus, Van Slyke, principal glass part OTA ya abe cet Pidgin ell ie ese Pte we ch ee 15.00 3591a. ditto, but mounted in wooden frame with special clamp for attachment to support rod to reduce danger of breakage: \(not illustrated) sys. tec gs fie a how hah Sea hosed Bak 3 Sakoh lente a ce laenepe .... 17.50 3592. Blood Gas Apparatus, Van Slyke, Precision Model, in which the diameter of the graduated measuring tube is reduced and graduated into 100 instead of 50 parts. In this model volumes can be estimated to an accuracy of 0.001 ml. This device does not replace No. 3590, and is only recommended for certain kinds of work, particularly for estimation of CO, and Oy, in the same blood sample. Complete with support, clamps, and other accessories as supplied with No. 3590................... 24.50 3593. Blood Gas Apparatus, Van Slyke, Precision Model, principal glass part only..................... 18.00 5953. Leveling Bulb, only, 23 inches diameter, 130 ml capacity .........00...0 0.000 1.00 3595. Thistle Tube, with stem 75 mm long, for use with above outfit........0.0000.0.0000.0..0 00000... .20 3609. Apparatus, Barcroft & Roberts, for determining the differential pressure of blood gases. See Journal OPP YSTOLO GY XAT, OL Oe oo eset a. hss 404 RR ates ATO, Mies Tet, antes ss ced Peete ora eats ete ae 24.00 . Apparatus for Determining the Differential Pressure of Blood Gases, Barcroft, for the use of very small ue a caianeties of blood, i. e., 0.1 ml. As used in the systematic determination of the haemoglobin worth or dissociation curves of human beings...............00.0 0.00. c cece eee eee 20.00 ioxide Apparatus, Fridericia, for the clinical determination of CO, percentage in alveolar air es SS ae acidosis of the blood; a simple and practical device for both the collection of alveolar air and the estimation of the CO, percentage without the use of the more elaborate gas analysis apparatus. See L. S. Fridericia, Berl. Klin. Wochenschrift 51 : 1268, 1914, and J. R. MacLeod, Journal of Laboratory and Clinical Medicine, April, 1916. Glass part only, mounted on a black VtAl CAML GOLD AC Kise sates eta ah clecaly 9m lees VR ns Sara ttre Vc te DAL aac cia cas RP Ee Cah ese he ec I 12) 3610 JAQUET PORTABLE POLYGRAPH, New Model, an instrument of great precision and_ convenience, by many considered the most sensitive mechanical device for the graphic study of the circulation. The clockwork runs for 25 minutes at the lowest speed of 1 em per second. Tracings can be made of any desired length from a continuous roll of paper, and at any speed from 2 mm to 50 mm per second. The clockwork is of the highest precision, marking time in either 1 or 1/5th second. A recent improvement in the sphygmograph attachment for radial pulse permits the attachment of the wrist-band with the receiving tambour removed in order to con- veniently locate the radial pulse exactly in the open space of the wrist-band, after which the receiving tambour of the sphygmograph can be quickly attached in exactly the correct position. The workmanship and finish are such as are embodied in no other instrument for similar purposes. 3610. Polygraph, Jaquet Portable, as above described, for recording three simultaneous tracings, either in ink or on smoked paper, i.e., radial pulse, apex beat, and one other, such as carotid, jugular, etc., in addi- tion to time tracing. With set of pens for both ink and smoked paper tracings, sphygmograph for radial pulse, cardiograph for apex beat, receiver for carotid, jugular, etc., and one roll each of glazed AITAGSINO SSE PoP sera he ed a raed vise ee tee ees eters on al aoa escort dch das Micrapraoelociceh 2 ee eC sth RM RA ENGR ROCESS Bear 204.00 3611. Smoked Paper, for use with Jaquet Polygraph. In roll containing approximately 80 ft., packed in cylin- drical paper'carton:..Perroll), $252) eo a ag ie eee ae ee ee le eee wae a ecterlde as 2.00 3612. Glazed Paper, for use with Jaquet Polygraph in making ink tracings. In roll containing approximately 200 ft., packed in cylindrical paper carton. Perroll............0. 0.0.0.0. c cee -90 10% discount in lots of 25 rolls. 25% discount in lots of 100 rolls. 3613. Pen, Ink Writing, short, for use on time marker............... ; a ron . 1.65 3613a. ditto, long, for use on tambour...... eae : F ae . 1.75 3614. Stylus, for Smoked Paper, short, for use on time marker selhaw leas . 65 3615. ditto, long, for use on tambour.................... z Grek tebe fae 85 3616. Ink, of a special grade, for use with Jaquet Polygraph. Perloz.bottle... cee ee ee eer) 3617. Sphygmograph, only, for radial pulse, as shown in above illustration with three straps for attachment POW CINE WES Uae stereos con ee SAR Fe meer an taser aah cee eon dlr a ee heir DAM Ohag tere hee TOTP LAOS ER 14.00 3618. Pneumograph, Marey-Jaquet, for taking respiratory movements. Suitable for use with Jaquet Poly- graph; butmotancluded! with thisoutht:. 2.2 wees ie as od one at ee ee de Gre es Gig BUS 33.75 3619. Cardiograph Attachment, for apex beat, with girdle, etc., assupplied with Jaquet Polygraph... ..... 26.50 ERLANGER CAPSULE, for use in connection with a polygraph and sphygmomanometer for recording vee in intra-arterial pressure, as suggested by Dr. Robert H. Halsey. See Archives of Internal Medicine, April, 1916. The attachment consists of the enclosed capsule devised by Erlanger and as used in the Erlanger Sphyg- momanometer. In the use suggested by Dr. Halsey a recording tambour of any polygraph is connected with the glass bulb at A by a tube in which there may be an equalizing valve. The tube B is connected with an inelastic leather covered armlet, 12 cm wide (usually a part of the sphygmomanometer outfit), while the tube C is connected with the sphygmomanometer. The inlet tube D with three-way stopcock controls the supply of air to the closed system, which consists of the rubber capsule in the glass chamber, armlet and the sphygmomanometer. This cock permits the pumping of the air with an ordinary atomizer bulb into the tube when set at ‘“‘On”’ and retained with cock set at ‘‘Off,”” but allowed to escape with cock set at ‘‘Out.”’ It is necessary to use the sphygmomanometer in order to determine the systolic and diastolic pressure, which must be known if it is desired to obtain tracings indicating variations in the arterial pressure, for the pressure in the re- cording system should be maintained at a constant point above the diastolic, usually at a point about one-third of the difference between systolic and diastolic pressure. With this attachment and the use of a sphygmomanometer any polygraph is easily applied to an artery, retained in adjustment without atten- rae and used to record the variations due to pulsus alternans and vasomotor changes. 3624. Erlanger Capsule, as above described, consisting of red rubber bulb enclosed in glass bulb, mounted on brass base, } inch square and 8 inches long, with three-way stopcock ............... 18.35 3625. Rubber Bulb, only, for use with Erlanger Capsule.............. 1.50 NotE—We do not sell Sphygmomanometers. These are to be had from any surgical instrument dealer. 150 S 3630 3630. 3632. 3634. 3635. 3636. 3637. 3640. 3641. 3642. 3643. 3644. 3650. 3651. 3652. sarco y ) 3636 3640 3641 j 3644 Blood Capsules, Wright, of soft glass, 2} inches long. PerlO.............0..0 00.0000 cece cece .70 Blood Pipette, Wright, of soft glass with end rounded for convenient application of rubber tube, and care- fully drawn point. Length over all 7}inches. Perl0.............. 0.0.00. c cece ee -70 Blood Collector, Vacuum, Keidel, for collection of blood for Wassermann and other tests; consisting of an ampoule of 5 ml capacity from which the air has been exhausted, a piece of rubber tubing, a syringe needle and a glass tube to protect needle after sterilization. Perdozen..................... 1.80 ditto, but without rubber tubing, needle or glasstube. Perdozen............................ 1.30 Directions for Use. Select a prominent vein in the forearm and cleanse the place at which puncture is to be made with soap and water followed with alcohol. A tourniquet may be applied to the arm above the elbow if necessary to make the vein more prominent. Remove the needle cover and draw the wire from the needle. Feel carefully the ampoule tip through the rubber tube to make sure that it is not broken. Grasp the hub of the needle with the thumb and two fingers of the right hand. Thrust the needle obliquely into the lumen of the vein while making traction on the skin with the left hand to fix the vessel. Then with the thumb and index finger of each hand grasp the tip of the ampoule (within the rubber tube) and break by bending sharply. If the vein has been entered, a sufficient amount of blood will be drawn into the ampoule. If no blood is obtained at the first trial, the vacuum may be held by clamping the rubber tube just back of the hub with haemostatic forceps before the needle is withdrawn. Another attempt may then be made. Before withdrawing the needle, the tourniquet must be loosened to prevent extravasation from the vein. No sealing of the ampoule is required. Simply replace the needle cover before packing for shipment. Blood Culture Tube, Vacuum, Keidel. A 5U ml tube of conical shape to fit centrifuge holders, operating on the principle of the Keidel Blood Collector, and as suggested by Judd and Simon, The Journal of the American Medical Association, March 6th, 1915, Vol. LXIV, p. 822. With protecting tube, rubber connection and a No. 24 needle. Each...... Raining Reveals aes Sy tse 45 ditto, but containing 15 to 25 ml of glucose bouillon with 1.5% of sodium citrate added to prevent coagulation, and exhausted ready for use. Each................. Hasty Ange aia t Leas aa 50 Note—The usual practice in the use of unfilled tubes is to draw out the neck of the tube to a fine caliber without seriously weakening the glass. The tube is the1 connected with a suction pump and vacuum established. The connecting rubber tube leading to the pump is then clamped, slipped off and plunged into the culture media, and again connected with the suction pump. When the desired degree of vacuum is established the neck is sealed where it was previously drawn out. The entire apparatus is then sterilized for 5 minutes in an autoclave at 20 lbs. pressure, when the tubes are ready for storage or use at any time. The culture media recommended by the author is 15 to 25 ml of glucose bouillon, with 1.5% of sodium citrate to prevent coagulation, for each tube. ‘0 Blood Letting Needle, or N. Y. State Board of Health type Wassermann needle.................. . 10 Blood Lancet, Swan, for drawing blood. ...........0.0 0.0 cc cece eee eae: . 50 Blood Lancet, English form, single end, with guard screw to regulate the depth of stab........ . 1.10 Blood Lancet, English form, double end, with both points protected for carrying in the pocket........ 1.75 Blood Lancet, Spring, with lever release and adjustment to regulate the depth of stab; as used in the U.S. Army Medical Department 2.50 3650 Clock, (Victor Interval Timer). May be set for any period from a quarter minute to two hours. Keeps good time, and is well made andreliable.. 6... 2... eee sagen “4305 ditto, but with automatic electric time switch, as used with Spencer Ovens............ ....... 15.00 Clock, (Wizard Interval Timer). A high-grade clock in nickel-plated case, with precision alarm adjustable for loud or soft tone, and with computing bezel, setting from the face to signal any interval of time from one minute to sixty, and from one hour to twelve. With radium dial and illuminated hands and numerals, making reading clearly discernible in the dark. Has been found invaluable in lab- oratory work for all time experiments... 0.0... ene 7.50 Fy Be wR H. ‘THe (MAYS Ge SOy sMp Pr SAc EN) =Y: = > iifoubirhihlintoatesbodet Vaadoadeateatent gt ahasbanbcnsbcadteedadtebeatoctatt lehytoterbadiabetenhiobalatha 3656. 3657. 3658. 3659. 3660. 3661. 3662. 3663. 3664. 3665. 3666. 3667. 3670. 3671. 3672. 3676. Stand, for Nessler Tubes, circular, revolving form, of wood. For twelve 50 ml tubes ‘OOLHY (Ls wo aD D> bo COLOR TESTING APPARATUS Color Comparison Tubes, Eggertz, for the estimation of carbon and manganese in steel by the colorimetric method. Gapacityccil crawunrshe once e cbt ayysyh Sham oreae 8 od) cami ameAsed Semeur coy eeertyh ety creirhee 30 50 Graduatedamcmi sin Sac.ac- he nce ninsnwanien lade ah cinereus ene aan aid mal bide del) ve ty POE SCUOL TWO ain ds Nets oss ee tran Sep are ro cee Lo ee hea Ue at gate enciat 3.80 4.50 Per Seb Of LO Ur 2 etait A ie a raha a he A ee ent ng es eel Creo fe ct a cong ae ele 7.60 9.00 Color Comparison Tubes, Julian, same as No. 3656 but with bent ends. The bent end permits the mixing of the contents without the use of a stopper in the tube. The lower portion of the tube is ungrad- uated. Graduated irom ,smili.234.2.24 nade eos a bik aioe ea aie has Oo PA ee 5 to 30 10 to 50 Gradua tediiny rally wes ieGe canta eee ieee theeles\ere Sid pteetiaen eat ae teat Scheel etb acu nada te to POE SCUOLA W.O2e.5 5 ooo ee ip eS REA NS SAO ote Fy Bb Net BY 4.00 4.00 Ber setof four cory eens 1 ee a 8.00 8.00 Color Comparison Tubes, Nessler, low form. Height of 50 ml mark in 50 ml tubes 120 mm; height of 100 ml mark in 100 ml tubes 150 mm. Graduations ls. ic tex y cto okra ere ea recs Be scree eS ai anoint iae OER ae cee abel 50 100 50 and 100 Bek Cle asctiecer8 sent an te eae te, ne cael an Oy tebe noe wanaatare sia eh ede see tone 280 1.00 1.20 POF SCUOL SIX oo err Skee Boe Nae OM ae he I eee TAS a ar ae Re yo 4.80 6.00 7.20 Color Comparison Tubes, Nessler, American Public Health Association. With polished bottoms and 50 ml mark 210 mm high on 50 ml tube, and 100 ml mark 325 mm high on 100 ml tubes. Tubes in selected sets of six or twelve guaranteed to have either 50 ml or 100 ml marks within 6 mm of same height. See American Public Health Association ‘Standard Methods of Water Analysis,” 1920. Graduatlonsemles ers eel 4 sateen. eee eR Ce en te Bowes 50 100 50 and 100 ACH ecg ete en clad Sl ghia ana ad Cree et Merl era ne aS gy mg 85 1.20 1.45 PP CTSOU OL SEX pst eect eee ee se RA eran tein Lopes eet . 5.10 7.70 9.30 (Per SetOltwelvV eric... cos aban ates eons nesses de rites hea hee k g Goer estos . 10.65 16.00 19.50 Color Comparison Tubes, Nessler, with polished plate glass bottoms. These tubes are made of ordinary glass not entirely colorless, but with a polished circular disc of colorless glass cemented on in an electric furnace. The dimensions and capacities are identical with those established by the Ameri- can Public Health Association and listed under the preceding number. The selected sets are guaranteed to have the 50 and 100 ml marks within 6 mm of the same height. Graduation: cls 6:4 duals ce Mutonute 4 hose ha Boek Bees & thee rote gr evn actcloeeoaeela oes 50 100 50 and 100 Each oi: 2004s PRED eae oe eed tren em eae see ee gsi .. 2.00 2.40 2.90 (Per SCUOL SIMS iter ents hy AR OR Ba A ee ET ee RR .... 14.40 17.40 21.00 Perset.of twelve es -c48 cick tee ents eee cea donc een el oe en 33.60 40.80 49.20 Nessler Tube Support, of wood finished in dull black, with opal glass reflector set at an angle. The tubes are supported by a metallic ledge under the lower deck so that the bottoms of the tubes do not come in contact with the opal glass reflector. Supporting the tubes above the inclined reflector prevents the errors due to shadows in the old form. With twelve holes 34 mm in diameter for 100-ml Nessler tubes of the low form. Without tubes...........................---0 00 2.40 ditto, with twelve holes for tubes of the tall or A. P. H. A. form. Ror (2A. Po As Neéssler Pubes: Sizes. 6.5 cines pacndceicn ds oc amoets va ehh weaned: 50 ml 100 ml Bach withowtstubes soc cot ccna aeets hove h bneiania th Ge Rpg eet ees Me See 2.40 2.40 Camera, for comparing color comparison tubes such as No. 3662, etc. Improved form, with blue and TOU GCL ASS veers aa tete sts ee ten Pe tes Hk a eet tae Gina Ah cosa eRe lice a Reig hoon nase ek yt hear tat 10.00 A R T H U_ R H. T H O M A § Cc © M PA. NY COLORIMETERS : _ The fact that color is one of the most constant qualities of substances, and that any variation of color is an index of variation of other qualities, has made possible a convenient means of laboratory determination of relative value as in the case of the plunger type of colorimeters, or in reference to an absolute index of color value as in the case of the Lovibond Tintometers, or by absolute analysis in terms of wavelength of dominant hue or its complementary and the percentage of white, i. e., monochromatic analysis as in the Nutting Colorimeter. Colorim- eters of the plunger type with the two halves of the field of view illuminated by the light passing through the standard and unknown solutions respectively, were first made by Duboscg, of Paris, in 1854, and have been con- tinuously made since that time by the Duboscq firm and its successors, and are now also manufactured in the U. 8. : Special forms of Colorimeters for specific uses have been developed and are in wide use, e. g., the Schreiner Colorimeter for soil work, the Kennicott-Campbell-Hurley for water analysis, steel analysis, color variations of dyestuffs, etc., the Saybolt Chromometer for oil testing, and various applications of the Lovibond Tintometer Standard Glasses for oil testing and other purposes. A further wide use of the colorimetric method has been developed by means of standard indicator solutions for specific tests, such as the Rowntree and Geraghty renal functional test, Marriott’s blood plasma alkali reserve and alveolar air tests, and the Levy-Rowntree-Marriott H-ion concentration of the blood test; and also the Clark and Lubs indicator set for the determination of H-ion concentration, particularly in culture media. ; In the past fifteen years very sensitive colorimetric methods have been developed for quantitative determi- nations in the analysis of blood and urine, following the pioneer work of Folin in 1904, when his colorimetric method for the estimation of creatinine in the urine was announced. For accuracy and rapidity in these methods, colorimeters of the plunger type are recommended, such as the Duboseq, Bausch & Lomb-Duboscq, Kober and Bock-Benedict. Colorimeters of the wedge type offer the advantage of the individual wedge for permanent standards with the disadvantage that these individual wedges must be empirically standardized and that few of them are really permanent, and careful calibration of each wedge by the individual using the instrument is often omitted. Where the volume of liquid is so large that the addition of one or two drops of fluid more or less does not impair the accuracy of the test, a dilution or test tube type of Colorimeter yields very satisfactory results, especially for occasional estimation. A large bibliography is now available in connection with the use of colorimetric methods in blood and urine chemistry. During 1920 a series of articles by Victor C. Myers under the title, “Chemical Changes in the Blood in Disease,”’ was published in the Journal of Laboratory and Clinical Medicine. These are now published in book form under the title, “Practical Chemical Analysis of Blood’ (C. V. Mosby Co., 1921). Recent investigations have developed some limitations which must be recognized in the colorimetric comparison of solutions of substances the colors of which are visually alike due to different absorption spectra. For instance, Newcomer, Journal of Biological Chemistry, 37 : 486, 1919, states, ‘‘It is thus essential in order that a color match be satisfactory under varying conditions that the absorption curves of the two substances composing the match be as nearly alike as possible.”; and K. G. Falk and H. M. Noyes, Journal of Biological Chemistry, 42 :129, 1920, ‘‘In order to be certain of quantitative results, the standard and unknown solutions, containing two colored substances, would be very nearly alike in composition and concentrations. The errors introduced otherwise may be considerable.” 3680 3684 3680. Colorimeter, Schreiner, as used in the U. S. Bureau of Soils. All working parts coming in contact with the sample or standard are of glass. Broken parts are easily replaceable. See Journal of the American Chemical Society, Sept. 9, 1905, and Bulletin No. 31 of the U. S. Department of Agriculture, Bureau Of SOUS oe erctiek eaebieliswra tous 2 eae roeniey cries tics Ca eaten hone is rie aS Alea ceveeeee es. 34,00 3681. Graduated Tubes, for Schreiner Colorimeter. Please give size of opening when ordering. Per pair. 3.75 3682. Plain Tubes, for Schreiner Colorimeter. Please give size of opening when ordering. Per pair.... 1.00 ° lorimeter, Kennicott-Campbell-Hurley. This instrument is used in the analysis of water, determination an ee of carbon in steel, titanium metal, etc., and for the color variations of dye stuffs. See Journal of the American Chemical Society, July 1912.00... 0.0.00 cee eee tenet teens 28.00 3685. Graduated Tube, only, for above Colorimeter........ no nina esenyang cuaan arnt etsnaatinasadtaaa EM ea Craters 1.75 3686. Graduated Tube, with leveling system, for above Colorimeter..........- 06-00-00 eee e este e eee ees 6.00 153 AU GR TSH CUS _ UR HH. T H ©O M A 5 Cc -O0 M P A N Y COLORIMETER, BAUSCH & LOMB-DUBOSCQ. While the original Duboscq design as to the optical arrangement has been followed, notable improvements in the design of the cups and other mechanical features, the result of suggestions of Dr. Otto Folin, are embodied in the Bausch & Lomb model. The movable cups for holding the liquids under examination, consist of thick-walled cylinders of glass. These cylinders fit into tubes of brass, threaded at the lower end so that by means of a metal screw cap, a plane glass plate may be forced firmly against the glass cylinders, the ends of which are finely ground in such a manner as to secure a water-tight joint. A rubber washer is placed between the glass plate and the shoulder of the metal screw cap for the purpose of equalizing the pressure and preventing the possibility of breakage. The plate which forms the bottom of the cup is made of optical glass having plane parallel surfaces. The metal sleeves, which surround the glass cylinders, are slotted so that the height of the liquid in the cups may be observed readily. All parts of the cups are interchangeable. The tube may conveniently be shaded by turning the single slot to the rear. They can be thoroughly and easily cleaned, and in the event of breakage of glass parts replacements can be made without inconvenience or delay. The pinions and operating heads are always in a fixed location, so the observer’s readings are controlled only by observation and not by the position of the pinion heads, thus tending to eliminate the personal equation in this detail. Two solid glass plungers of optical glass, matched for color and having optically plane and parallel ends, are attached to the frame of the instrument by means of metal adapters into which they are firmly cemented. They are located in a fixed position in the axis of the instrument, which passes through the centers of the cups. Any injury to cups or plungers which might be caused by bringing them violently together is prevented by means of two adjustable stops which determine the highest position to which the movable cups can be raised. The scales are graduated in millimeters and are provided with verniers to indicate the depth of liquid between the lower surfaces of the plungers and the bottom of the cups to within 0.1 mm. When the stops are so adjusted that the plungers and cup bottoms can just come in contact, the scale should read zero. This can be brought about by moving the verniers, which are adjustable, into the proper position. The dividing line separating the halves of the field of the instrument as viewed through the observing microscope is formed by adjacent ends of the rhombohedral prisms, on which two narrow surfaces have been polished in order to obtain close contact and a thin smooth line. The field of view of the observing microscope appears as a circle, divided into halves by the dividing line. On account of the inversion caused by this microscope, the light which illuminates the right semicircle thus formed has passed through the left beaker, plunger and prism, while that illuminating the left semicircle has passed in a like manner through the right beaker, plunger and prism. In this manner is formed what is essentially a photometric field, by means of which comparisons of intensities may be accurately made, the principle of the instrument being based on the adjustment of the depth of the liquids in the cups, so that the appearance of the two adjacent halves of the field is identical. In other words, when the two halves are matched, the concentrations of the two solutions in the beakers are inversely proportional to the depth, read directly from scales in rear of instrument, of the liquids between the lower surface ‘of the plungers and the bottom of the cups. The observing microscope consists of an eyepiece and an erecting system. The purpose of the erecting system is to permit the introduction of diaphragms to act as limiting apertures, by means of which a correct passage of light rays through the instrument, an evenly illuminated field and an absence of disturbing reflections are brought about. A hinged cover is provided for the purpose of shutting off all extraneous light which might in some cases affect the settings. The purpose of the ray filters is to permit, when necessary, a modification in tint of the liquids to be studied, so that a match of intensities may be obtained more rapidly. The ground glass discs, when placed in the light path at the same point as the ray filters, will effect a reduction in intensity, and a very thorough diffusion of the light entering the system. Directions for Use. While each instrument is carefully adjusted and passes detailed inspection before being packed for shipment, to test the adjustment of the instrument make sure that the bottoms of the caps are in contact with the lower ends of the plungers at the zero position of the scales. If this condition has not been fulfilled, make the necessary adjustment of the stops as well as of the verniers. It is to be noted in this connection that the position of the bottom of the cylinder with respect to the lower surface of the plunger may be slightly varied by tightening or loosening the screw cap which forces the rubber washer against it. Care should be exercised not to scratch the lower surface of the plunger by rubbing the cover glass against it under pressure. In order to obviate all danger of damage to the surfaces of both, it is advisable to place a thin piece of tissue paper between them while this adjustment is being made. Rack the cups down to their lowest position, and remove them from the instrument, taking care that they do not strike the glass plungers. Turn the entire instrument toward an even, ample source of light, preferably diffuse daylight, or very white artificial light, and, while looking through the eyepiece, adjust the instrument and the mirror so that the two halves of the field appear of the same color and of equal brightness. In this connection we recommend consideration of our electric colorimeter lamp, No. 3746. Pour a small quantity of ‘‘known”’ solution into one of the cups, and into the other cup some of the “unknown” solution. The cups should be not more than half filled with liquid, to avoid the danger of forcing some of the liquid over the top of the cup and causing it to spill on to the mirror or into the working parts of the instrument. If it should appear desirable to use a greater depth of liquid on account of faint coloration, care should be taken not to force liquid over the top of the cup. Replace the cups in the instrument, and raise them by means of the racks and pinions until the lower ends of the glass plungers are well immersed within the liquids. Air bubbles, which in many instances are formed under the ends of the plunger, may easily be removed by slightly tilting the instrument. Now, while looking through the eyepiece, adjust the heights of the cups until an approximate balance is obtained on both sides of the field. It is now convenient to set the ‘“‘unknown” liquid so that its depth, as shown on the scale, is an exact number of millimeters, and then to raise or lower the ‘‘known”’ liquid until a match is secured, i. e., when both halves of the field appear equally bright and identical in color. Readings are now taken by means of the verniers on the scale and recorded. To secure results of the greatest accuracy it is necessary to take the average of a number of independent readings. When the two halves of the field are of the same brightness, the color intensities of the two solutions are inversely proportioned to the depths of the columns of the two solutions. Let C; =color intensity of the known solution; D, =depth of the known liquid, as read on the scale, S; C2 =color intensity of the unknown solution; D».=depth of the unknown solution. Cy Dy 2. Then—Cy De=C, “D, and Cy = Let us suppose that our known solution contains 80 ccm of coloring matter per liter of liquid, in which case C, = 80, and that observa- tions have been made as follows: Readings Cy D, Dz, Computations I 80 10.1 18.0 ee SOOT 89 Il 80 14.0 25.0 Cy 4-9 = 44.80 HI 80 18.5 33.0 C= 8 =44.85 154 3690 Front view. Side and rear view COLORIMETER, Bausch & Lomb-Duboscg (continued) 3690. Colorimeters, B. & L.-Duboscq, as described on preceding page, in case. Height of tube, Cis i.a.cc ac canna bier Mic cemaiaten. ; aa Eat a 5 10 Wate ht) Ges tt eee ite reser Sahstsee ea ere eed ma Tes Bok teehee Mae te deere nan cele ete ah ara mtn Ak Se 125.00 165.00 3691. Glass Cups, complete. Each... pie akon : Re eee raes 5.50 8.00 3692; ‘Glass: Cylinders, only. Bae ince occ, see .ntelas Glog wos hls Buea D toads GEA an Shabana 1.65 1.85 3693. Glass Plungers, only, octagonal, with threaded metallic adapter. As correct readings require that these plungers be accurately matched, they are sold in pairs. For height of tube, cm. 5 10 POT DAMN eosin csi acse a toes nae Sa GPG ty ee A Ek TH ecg oO ee Ree oe deh Greene) 15.00 20.00 3694. Discs, of plane glass, to form bottom of cup. The same size is used for each instrument. Per dozen... 4.00 NEPHELOMETER ATTACHMENT for Bausch & Lomb-Duboscq Colorimeters. The colorimeter can readily be converted into a nephelometer or turbidimeter by means of an attachment consisting of a light source, a pair of condensers, two vials for holding the liquids to be measured and two tubular metal light shields which surround the vials in such a manner that the depth of the liquids illuminated by the light source can be varied. Two glass tubes in the form of the ordinary tube vials are attached at their upper ends to metal adapters by means of circular spring clips, which exert sufficient pressure to hold them securely in position when they are filled with liquid. Glass stoppers with plane and parallel optical surfaces are inserted through the metal adapters, so that their lower surfaces extend into the liquids in the vials. These glass stoppers have shoulders which, resting on the upper end of the adapters, hold them in position. The position of the lower surface of the stopper coincides with the lower edge of the metal ring, which is a part of the adapter and serves as a light shield for the upper end of the vial. The stoppers serve a two-fold purpose; first, to remove the meniscus from the surface of the liquid column; second, to determine the upper limit of the liquid so as to obviate the necessity of filling the vials to a definite point. The metal adapter carrying the vial and the stopper is threaded so that it can be attached to the colorimeter in place of the plunger. The two tubular, metal light-shields, consisting of lacquered brass cylinders mounted on metal bases in such a manner that they may be adjusted in height for the purpose of obtaining the correct zero setting, take the place of the cups or beakers of the colorimeter. By means of the racks and pinions these tubes may be raised and lowered precisely as in the colorimeter so that light directed horizontally towards the vials may be partly or entirely cut off, 7. ¢., so that the height of the column of liquid illuminated, and therefore reflecting light into the optical system of the instrument, may be varied. Illumination is obtained by means of a 250-watt Mazda lamp mounted in the focus of a pair of condensers, which project a beam of parallel rays horizontally into the vials containing the liquids under examination. The lamp and condensers are mounted in a well ventilated, light-proof lamphouse. Extending from the lamphouse is a metal light shield so constructed that, when the colorimeter is placed in position in front of it, all extraneous light is shut out. ee ; From the above description of the nephelometer it will be evident that some of the light which strikes the particles suspended in the liquids will be reflected into the coincidence prism of the instrument and will consequently reach the eye, and that the brightness of the field will be determined by the number of particles reflecting light, so that quantitative measurements of turbidity may be made by matching the field of the “unknown” liquid with that of a standard or “known” liquid of given concentration in the same manner in which this is done in colorimetric measurements. It is supplied in two sizes: one for the 50 mm, and the other for the 100 mm colorimeter. 155 3702 NEPHELOMETER ATTACHMENT (Continued) 3696. Nephelometer Attachment, B. & L., as described on preceding page, with 250-watt Mazda lamp, for use with 5 cm Bausch & Lomb-Dubosceq Colorimeter. With cord and plug for 110-volt circuit.. 75.00 3697. ditto, but for use with 10 cm Bausch & Lomb-Duboscq Colorimeter. With cord and plug for 110-volt CUCU biags acceso crore ees ue aap telat es ey cel OR AMIR sey nod Aa nana Ree UC een oe Meat ee 90.00 3698.) ‘Lampobulb,.250'watts) only sa... ag eneacee peasants omnia le ny ee deers Rend e aes ARAN enn ft 3.50 3699. Nephelometer Tubes, only, of glass, as supplied with the Nephelometer Attachment for 5 cm pelos Per pair.............. Becgie tbat Maras eniine AAMT Ahr ton peeps) RENE eg NTT Mets Nate tO 3790. Raines Tubes, complete with metal light shields, as supplied with the Nephelometer nee it Per Dall Stoel ere ttt ee Ee En hate Meg entrn A ech Canc tel cy ene ote un EAS Seer ee R 3701. Glass Poe 40 mm, with threaded adapter, as supplied with the Nephelometer Attachment. POL DAIGY evs so a Aa naaek GRAIN cree aie ck penal emery MemNN (re AIG NAGS fad stpte ane DAs ae Wel Bee 11.00 3702. Colorimeter-Nephelometer Outfit, B. & L., consisting of No. 3690 Colorimeter 5 cm and No. 3696 Nephelometer Attachment, with cord and plug for 110-volt circuit..................... 200.00 3703. Colorimeter-Nephelometer Outfit, B. & L., consisting of No. 3690 Colorimeter 10 cm and No. 3697 Nephelometer Attachment, with cord and plug for 110-volt circuit..................... 255.00 Directions for Use. Remove the hinged cover, plungers and cylinders from the colorimeter. Attach the metal adapters carrying the glass stoppers to the instrument in place of the plungers. Pour the known and unknown liquids into their respective vials, filling them to within about 6 mm of the top. Place the vials into position in the spring clamps of the adapters so that the lower surface of each stopper is immersed in the liquid. Air bubbles, which are likely to form as this is being done, and which result in inaccurate readings if allowed to remain, may be easily removed by tilting the instrument from its horizontal position. Place the tubular light shields on the projecting plates, which carry the beakers, and rack them up until the scale reading is zero. Adjust the height of the metal tubes by means of the set screws, which hold them in the bases, until the top ends of the tubes coincide with the lower ends of the adapters, which function as light shields for the upper ends of the vials. The accuracy of this zero adjustment may be determined by placing the instrument into position in front of the light source. If both halves of the field appear entirely dark, but begin to brighten up at the slightest downward motion of the tubular light shields, the adjustment may be considered satisfactory. If, however, either or both halves of the field appear illuminated at the zero position of the scale, the corresponding light shields wil! have to be raised. If a shield has been raised too far, that half of the field will appear dark, but an appreciable downward motion will be necessary before light is transmitted. 2 Now make sure that the instrument fits properly against the lamphouse. A height adjustment of the lamphouse may be obtained by loosening the thumb screw which fastens it to the standard. Measurements may now be made in pre- cisely the same manner as described in connection with the directions for use of the Duboseq Colorimeter. 3706. Colorimeter, Bausch & Lomb-Duboscgq, Small or Biological Model, similar in general construction to the larger B. & L.-Duboscq instruments, but with cups 4 cm deep. The position of both cups is read by means of vernier to 0.1 mm, but only the right-hand cup to contain the unknown is furnished with rack and pin- ion. A convenient model for use in bio-chemistry. Withoutscase 5: ica Rela vg vente, oe ile 60.00 3707. Case, only for No. 3706 Colorimeter.............. 3.00 3708. Glass Cups, complete. Each................... 5.00 3709. Glass Cylinders, only. Each.................... 1.50 ) 3710. Glass Plungers, only, octagonal, with threaded adapter. As correct readings require that these plungers be accurately matched, they are sold in pairs. Peripaitiss «Michi. cust er wad cel icale eee eenvantabtout stint 11.00 156 3712 Front view. Side and rear view. COLORIMETER, DUBOSCQ-PELLIN. This is an improved form of the original colorimeter announced by Jules Duboseq in 1854 and still made in the factory of his successors. With the great revival of interest in colorimetry, particularly in its application to physiological chemistry as a result of the pioneer work of Otto Folin in connection with the determination of total nitrogen in urine, non-protein nitrogen, urea and ammonia in blood, urea in urine, etc., in 1904, this particular instrument assumed an importance in clinical and biological investigations equalled perhaps only by the microscope. The construction of the original Duboscq Colorimeter is in general similar to that of American make described on preceding pages, and the discussion of underlying theory and directions for use there given are equally applicable to the French instrument. This instrument is more widely used throughout the world than any of the other plunger type colorimeters and is preferred by many investigators to any other make. 3712. Colorimeters, Duboscq-Pellin, as above described, with scale divided in millimeters reading by vernier to 0.1 millimeter. With set of eight tinted and two ground glasses for modification of tint. HMCIgh Hob GUDeS CMe sai x sce ease eon aves ans alder en te ven ater otras oe Ry hee eA 5 10 Each 92.00 149.00 B7is. (Glass Cups, only. Per want. cecs cache vues beds ga ee ae earn ieeeeece. . Oe 9.60 3714. Glass Plungers, only, octagonal, for Duboscq-Pellin Colorimeters. As correct readings require that these plungers be accurately matched, they are sold only in pairs. Heightiof tube; ccimiys sce) 8 see i onthe rey lapel euin e wie Mer au pula 5 10 | Ee) sh: Sener eee pr arner de Eres trape h Re er ieeae AOE HOO Pr Self ERNE tre se EMEY rR Relea RN ore 11.50 15.00 3715. Case, only, of polished wood. For Colorimeter, sizecm....................0.00.. 5 10 Bac ete te eave a trope cis Oo ntra nats oat ses nrntrgl len oead ak Gene eet Ota Sater Mes 7.50 8.50 3716. Colorimeter, Duboscq-Pellin, Biological. A small size instrument similar in principle to the 5 cm and 10 em Duboscq Colorimeters, but designed for use where only very small quantities of solution are available, as in certain investigations of blood, sera, etc. Determinations can be made with less than 1 ml of solution. The maximum movement of the plunger is 20 mm, with vernier reading to 0.1mm. The capacity of each cup is 2 ml and the diameter of the glass plunger is 7 mm. This model has been improved in that the metallic cups previously furnished are now made of glass, as are also the plungers; and separate racks are provided for each tube as in the larger models. 62.00 3717. Glass Cups, only, for Duboseq-Pellin Biological Colorimeter. Per pair........................ 5.50 3718. Glass Plungers, only, for Duboscq-Pellin Biological Colorimeter. Per pair....................-. 5.00 3719. Case, only, of polished wood, for No. 8716 Colorimeter.........00..0 000 ccc eee 6.00 3460. Colorimeter Attachment, Newcomer, for the clinical estimation of oxy-haemoglobin in the blood in Haldane scale percentages, consisting of a plate of a certain high transmission yellow glass 22 mm square, accurately ground and polished, for insertion in Duboscq Colorimeters, in the light path of one of the cells—at the top of the plunger. This attachment may also be used in the Bock- Benedict Colorimeter, placing it below the mirror FM (see diagram on page 159). The light fields should first be balanced with water in the cup C and the cell S removed. Each glass plate is calibrated and engraved with exact thickness and a correction table is furnished with each attach- ment. Readings should be taken through Daylite glass, such as is provided in our Colorimetry Lamp No. 3746. The Mazda ‘‘Daylite’’ bulbs provide a fairly satisfactory and inexpensive illumi- nation for this purpose. See Dr. H.S. Newcomer, Journal of Biological Chemistry, March, 1919 3.50 3449. Pipette, Capillary, graduated at 20 cubic millimeter, for diluting blood in the use of Newcomer Colorimeter sterol rng ra 6 ose Soie cost see oo ne ess wo es egw HO AE RNS Asus BGS BE HEE SEIS LES 1.50 3725. Fig. 1 3726. Fig. 2 KOBER NEPHELOMETER-COLORIMETER. A convenient combination of the plunger type for the measurement of absorbed light, and of a nephelometer for the estimation of the light reflected by substances in suspension. The cups are entirely separated from each other by a metal division, thus eliminating the spatter- ing of solutions from one cup into the other. The parallelopipeds are attached to a separate plate and can be easily removed for cleansing. The mirrors work independently for each tube. The plungers and cups have fused on bottoms resistant to all acids, alkalies and heat. Movement of the cups is provided by the convenient turning of the threaded rods on which they are supported. The colorimeter cups are of opaque black glass with transparent bottoms, while the nephelometer cups are of transparent glass with opaque black glass bottoms. The instrument may be conveniently changed from a colorimeter to a nephelometer by a change of cups and attachment of the illuminating device, which also serves as a convenient colorimetric lamp where artificial illumination for the reflecting mirror is desired. In Fig. 2 is shown the colorimeter with the lamphouse and colorimeter mounted on base. See Journal of Biological Chemistry, March, 1917, ‘‘An Improved Nephelometer-Colorimeter;’’ Journal of Industrial and Engi- neering Chemistry, July, 1918, “Technical Applications of Nephelometry,” by Philip Adolph Kober; and Journal of Biological Chemistry, June, 1921, ‘Further Improvements in the Nephelometer-Colorimeter,”’ by Paul A. Kober and Robt. E. Klett. For use of this instrument for turbidity in certain bio-chemical methods of analysis, see W. Denis, Journal of Biological Chemistry, June, 1921. 3724. Colorimeter, Kober, Improved Model, with Klett Top Reader, whereby the scale is conveniently read through a lens by reflection without removing the eye from the vicinity of the eyepiece proper, thereby avoiding stooping down for the scale reading. This feature is not shown in illustration, but the instruments are otherwise identical.............00000. 000000 eee 90.00 3725. Colorimeter, Kober, Original Model, as shown in Fig. 1, with one pair of 65 mm colorimeter cups, 7. é., black opaque glass with transparent bottoms, and plungers......................2..0--. 75.00 3726. Nephelometer-Colorimeter, Kober, Original Model, consisting of Colorimeter proper as listed under No. 3725, with the addition of lamphouse as shown in Fig. 2, and with one pair of 65 mm and one pair of 115 mm colorimeter cups, i. e., black opaque glass with transparent bottoms; one pair of 65 mm and one pair of 115 mm nephelometer cups, 7. e., transparent glass with black opaque glass bottoms; incandescent lamp with cord and plug, mounted on black polished board with switch. For 110- ViOlGICIE CUI crares pecicne Ghee ene De ye A PS BEN ESS Su GS Skee eA IE ABE. dhs ns pte moe 120.00 3727. Nephelometer-Colorimeter, Kober, Improved Model, consisting of Colorimeter proper of the improved type with Klett Top Reader and Lamp House, and accessories .......................-0 00 135.00 3728. Colorimeter Cups, of black opaque glass with transparent bottom, for use with daylight. Height, mm............. ESF eh Ags eR SAA ANE Die eda: ior At aie al es 5; 65 115 _ Per pair........ Hi Riek come ae pe aaa ee CETTE eee ee ae oe ee 4.50 4.50 3729. ditto, but of black glass with blue bottom, for use with artificial light. Height, mm.... eet redeeas ce GeO EES A Fag RC OMIT GAS 65 115 _ Per pair Soaked Pe ee ee re BING A TESA A ie ei ene acne ate eciiaeth wed ae ee 5.00 5.00 3730. ditto, but of transparent glass with transparent bottom, for use with daylight or artificial light. These are used for solutions that require no screening. Height, mm.... Ouray yd pues ser sae er os aC PEt tee cle a watemncehy BAW ik 65 115 Per pair......... ae ees Sanches OE Ee eee eee ee ee ee a 3.50 3.50 3731. Nephelometer Cups, of transparent glass with black bottom, suitable for nephelometer work only. PU CTO ING, SIMI jepson ras ee wi gma oennadeenent eee eit capt Sete te Mee net ween Sakae tte 65 115 Per paiti: ace wen kadar si WAN rc raat Bayveeh Re ce ah ae EOE SI A ee goat ks ue al 4.50 4.50 3732. Plungers, only, for Kober Colorimeter. As correct readings require that these plungers be accurately matched, they are sold only in pairs. Per pair...................................-..22, 4.50 3733. Incandescent Lamp, for 110-volt circuit............. Ns 3736 3736 Diagram showing path of the re- Diagram show- flected beams of light. ing mirror ar- rangement. 3736. Colorimeter, Bock-Benedict. A new form of colorimeter of simple construction and moderate price, designed particularly for bio-chemistry. The expensive pair of parallelopipeds forming the main part of the optical system in the Duboscq Colorimeters is replaced by two mirrors HM and FM of the above diagrams, one of which (HM) reflects the light from the unknown solution, and the other (FM) the light from the standard solution into the observation tube. The division of the field is accomplished by the relative arrangement of these mirrors, as shown in diagram. See Dr. Joseph C. Bock and Dr. Stanley R. Benedict, Journal of Biological Chemistry, August, 1918, “A New Form of Colorimeter.’’ Complete with one cell for the standard, 15x 20 mm...... 40.00 3737. Cells, only, for Bock-Benedict Colorimeter. Sizemm....................-..0.00- 8 x 10 15 x 20 AC a eeiseere ee eee ea eae SONS MEA cote ea areertrsranay hea ra arc Ace ee 2.30 2.30 ESOS. VRP G CPSs OT yas IAC Utes overs ey oe ek eH ate nea or lash Pa tae CW a chen aA See An Net eel ardds TA Re nS 1.15 37395) Cups; onlys 9 "Hae tence eta oem eee tye Gteln an dee htt aa sag Maaaa yeasie geliiuar a eddale 1.15 Directions for use of Bock-Benedict Colorimeter. Run up cup C until the bottom of cup and bottom of plunger P meet. See if the vernier on scale reads Zero. If not, run the cup down again and then loosen the set screw SC. Pull plunger down a few millimeters and run the cup slowly up again, while closely watching the vernier and scale. As soon as the vernier has met the Zero point, tighten the set screw of the plunger and the instrument is properly set. It is always advisable whenever work is started or a new cup is used to check the instrument in the above manner to insure absolute accuracy. In order to use the Colorimeter, put square dry cell in place filled with water. Attach the housing and fill the cup with water, raising it to meet the plunger. Looking through the telescope, move the large reflector until both fields are exactly equal. Now put standard solution in the cell and unknown solution in the cup. Move cup slowly up and down by means of pinion wheel until fields appear even. Read scale. By turning the cell 90° another depth of standard color is obtained. All readings must be taken with housing in place. Colorimeter, Universal, after Autenrieth and Koenigsberger, now manufactured in the U. S. under license of U. S. Patent No. 998,091. This is a colorimeter of the wedge type, particularly valuable where only small quantities of the unknown are available. The hollow glass wedge for the standard solution and the trough for the unknown, together with scale and prism, are conveniently mounted in a small wooden housing. When used with phenolsulphonephthalein solution as standard, this colorimeter is satisfactory for the Rowntree and Geraghty test for functional ability of the kidneys, and for the determination of the relative efficiency of each kidney. A description of convenient methods for preparing standard solutions for clinical and physiological work as suggested by various authorities is to be found in “‘The Newer Methods of Blood and Urine Chemistry,’’ by Gradwohl and Blaivas. 3742. Colorimeter, Universal, Autenrieth and Koenigsberger, as above described. Without wedge, trough, GT sVSLV Ota CG CAS Coir cost 3 ce lec oeccde ear tetera Ice i oan ach oa cl, anal Bele ots cand AA aa eee eyo ie 40.00 3743. Wedge, only, empty, hollow glass with ground stopper............0.0 0.0.0 ccc cee 9.00 3744. Glass Trough, only, for unknown solution.............0.00.00 000000 ee 4.50 3449. Pipette; eraduated ZOvCMmM ea cecgace no otto mesma ttedocomtiavats ch iseceh sea esceibe daeut fe Ahan equtide Se ecereaRee tate ade eh 1.50 COLORIMETER LAMP, Bausch & Lomb. The Chalet form suggested by Prof. S. H. Gage (see Science October 15th, 1915, pp. 534-6) has been modified in accordance with suggestions of Dr. H. S. Newcomer; see Journal of Biological Chemistry, March, 1919, in order to suit the requirements of colorimetry work. The illumi- nant consists of a 100-watt, 110-volt Mazda lamp in a light-tight housing, with projecting eaves to shade the eyes of the worker, and with a window equipped with Corning Daylite glass, 82 x 82 mm, giving an almost pure white light. The ventilation is arranged to allow sufficient light for making notes, but no direct light reaches the eye. A spherical glass mirror of strong curvature reflects the light from the bulb, which is mounted in an adjustable plate for focusing and adjusting the filament with reference to the reflector. 3746. Colorimeter Lamp, Chalet Form, B. & L., as above de- scribed, with cord, switch and plug for 110-volt cir- CCUG eet der ial Takei a shed hen Rone ac SR cee eae 19.50 3747. ditto, but with resistance for use on 220-volt cir- CUI Ge ersk e eamn eam Ataris ute tiath eke Mire eRe 2 3748. Resistance, only, for use with 100-watt, 110-volt Mazda 3 lamp, on 220-volt circuit.................. 8.00 3746 3749. Lamp Bulb, only, 100-watt, 110-volt Mazda bulb.. 1.35. 159 Ay GR. AI da Wh uR HH: T tH oO Mm As €. ~O.. M "RP A N —¥ 3760. Fig. 1 MYERS COLORIMETER. A small and relatively accurate dilution form of colorimeter as suggested by Dr. Victor C. Myers for the clinical estimation of urea, uric acid, creatinine, blood sugar, renal functional test, etc. See, The Journal of Laboratory and Clinical Medicine, 5 : pp. 343 and 418, 1920, and 1: 760, 1916. Consisting of two tubes of identical bore graduated in 1/10 ml from 5 to 25 ml. The tubes are placed side by side in the colorimeter and comparison made through an opening 1 x 2 em against a white glass background. It is best to employ solutions of the substance to be determined, e. g., phenolsulphonephthalein, uric acid, nitrogen in the form of ammonium sulphate or chloride, creatinine in saturated picric acid solution and glucose in saturated picric acid solution, developing the color in the standard simultaneously with the unknown. No standards are quite as satisfactory as those prepared from the substance to be determined and treated in the same way as the unknown. The calculations with the instrument are very simple. If, for example, a blood sugar estimation is being made and the standard glucose solution is the equivalent of 0.1% blood sugar for the conditions used, then a dilution of the unknown to 15 ml represents 0.15% blood sugar. 3756. Colorimeter, Myers, as described above, complete........ 0.0... 00.000 cee eee 12.00 Stat “Gradtiated EUbeSs GRei Wain sce cio x08 news a6 cots rae sch tecurs in ee nerseaties orapesiceedeemn aint rca alo nc yeves SL fds NE Rn RES adh 3.20 SUD SPU le rac ia semen ks ysea ala kctah a tet estes ommetn pletie Mace i hele ekd oats id ahd heh ok Fone ne dlc dy Py daca ea rll 75 NUTTING COLORIMETER, Hilger New Model. The main purpose for which the Nutting Colorimeter has been designed is the analysis and specification of colors, for instance, those of papers, powders, liquids, textile fabrics, color screens, or light sources. It is also an efficient instrument for photometry (including spectropho- tometry), visual sensibility determinations, hue sensitivity determinations and purity sensibility determinations. With this instrument, then, it is possible to measure and record numerically a color so that at any future time, and with a different instrument if desired, it can be accurately reproduced from the record. Obviously, too, determinations of color blindness and lesser abnormalities of color sensibility come within its scope. It is well known that any color may be analyzed and specified in either of two different ways: (1) in terms of three primary components, red, green, and blue (trichromatic analysis); or (2) in terms of wavelength of dominant hue or its complementary and the percentage of white (monochromatic analysis). Of the three elements of color, hue, tone, and luminosity, hue and tone are determined with a colorimeter, luminosity with a photometer or a photometric part of the colorimeter. In the present form of colorimeter the photometer is an integral part of the apparatus. Colors to be analyzed consist of light, either emitted from some source, transmitted through some selective screen, or reflected from some mat or semi-mat surface. Any one of these colors to be analyzed may be either spectral or purple, according to whether or not its dominant hue lies in the visible spectrum. Any analyzing colorimeter should then be applicable to emitted, transmitted or reflected light of either spectral or purple dominant hue. The advantage of monochromatic analysis lies in the elimination of the arbitrary reference standards (red, green and blue), readings being given in wavelength and per cent white. Both methods give readings varying somewhat with the observer, involving in some cases correction to the absolute color scale based on the average properties of a number of normal eyes. The Nutting Colorimeter utilizes the method of monochromatic analysis. Color measurement with this instrument is effected by mixing white light with light of a pure spectral hue. The hue, and the proportion of white are varied until the mixture matches the color to be analyzed. Finally the wave- length of the dominant hue and the percentage of white admixed are determined, and these two qualities (hue and purity) recorded as specifying the color determined. This procedure suffices for analyzing all colors except the purples. For these, light of a pure hue is mixed with light of the unknown color in such a proportion that the mixture is pure white, and the specifications of the color follow in an analogous manner. The Nutting Colorimeter is essentially a spectroscope with two additional arms, one to admit standard white light, the other the light to be analyzed. The instrument has been modified considerably from the original model; the latest form, which has been approved by Dr. Nutting, embodies many points which his experience has shown to be desirable. See Bulletin 9, Bureau of Standards, 1913, pp. 1-5, and Physical Review, 4, 2nd Ser., pp. 454-456. 160 A R T H U_ R H. T H O M A_§ Cc O M P A N_ Y LICHT FROM SUN ! , a ee R Ll ea ep L N ~V~ r= _ £ 3760 Fig. 2 NUTTING COLORIMETER (Continued) ; A general view of the latest form is shown in Fig. 1, and a sketch plan in Fig. 2. Cj, is the spectral collimator to admit light to be spread into a spectrum. The dispersing prism P is of the constant deviation type, thus permitting a fixed arm form of spectroscope to be used. The prism is rotated by a fine screw motion actuated by the drum D, on which the wavelength of the line under observation is read off direct in wavelengths. The intensity of the spectrum is variable at will by adjustment of the bi-lateral slit S, or by rotation of one of the polarizing prisms A. In this way a great range of intensity can be obtained in the spectral beam. In making measurements the rotation of the polarizing prism should be adopted, the relative brightness I! being determined in the usual way from the formula: mi I A being the reading on the circular scale attached to the outer polarizing prism, and J being the intensity when A=O. In what follows the brightness of the spectral component, as thus determined, is represented by Is. Cz is the white light collimator to admit the standard white light. This beam can also be altered in intensity by means of the polarizing prisms A». C3 is a collimator to admit the light to be analyzed, also with polarizing prisms Az for altering the intensity. C4is the observing tube. WM isa plate of glass, of which two sectors of 90° are silvered on the back, thus forming mirrors, the remaining two sectors of 90° being clear glass. The mirror axle has a pulley by means of which the mirror can be rotated, in its own plane, by a small motor. The light beams from colli- mators C, and Cy are brought by the Lummer-Brodhun cube B into favorable juxta- position with that from the collimator C3, so that an accurate judgment of match can be made. = cos? A 3760. Colorimeter, Nutting, Hilger New Model, as above described, with 14-inch diameter V groove pulley, to be run at 100 to 200 r.p.m., 1/50 h.p. motor isrequired. Without source of light or motor, as shown in illustration, but with complete set of directions.....................0..4.. 1711.00 3762. Chromometer, Saybolt Universal, for determining color shades of refined petro- leum. With two upright removable glass tubes, one of which has a transparent crown glass, oil tight bottom and draw-off cock. The oil to be tested is filled into this graduated tube. The other tube is similar but without graduations and has an open bottom, into which the stand- ard color glass or the two color glasses are adjusted. A prismatic eyepiece brings the two tubes into single eye vision, one tube containing the color glass standard and the other tube containing the oil under examination. Inasmuch as the density of color in a quid depends upon the height of a column of that liquid, an excess of oil is filled into the graduated tube and gradually drawn off until it coincides in color with the standard glass. At that point, the height of the oil column is noted by reading the graduations on the tube, which height determines the color shade. Complete directions for use are included with each instrument. Two glass color discs are supplied, and by the use of one or both together color shades can be determined between below zero to+25, zero being standard white and +21 water white. Complete, in case....... 80.00 161 A RR YT A U R 3770 3778 3770. Tintometer, Lovibond, for standardizing merchantable petroleums, and including the monocular optical instrument, box with stand and reflector, 18-inch cell and four special standard petroleum glasses, _ t.¢., water white, standard white, superfine white and prime white...................... 55.75 3771. ditto, but with the addition of a jg-inch cell and five additional standards, i. e., 1.5, 3, 4, 5 and 7, which cover the additional classifications for Intermediate, Russian and Lubricating Oils... 94.35 3772. 3773. 3774. 3775. 3778. 3779. 3780. 3788. 3789. 3788 Set of Four Tintometer Standard Glasses, only, for merchantable petroleums, as supplied with No. 3770, i. e., water white, standard white, superfine white and. prime whites ..0 écccnyisaias dao 5 aurde Kurd Gey ben nieanes 13.75 Set of Five Tintometer Standard Glasses, only, as supplied with No. 3771, and covering the classifications Intermediate, Russian and Lubricating OU Sra mee naeasks errtne wanes hana nk, a a ned airs eae eter area eta 17.50 Tintometer Cell only, 18-inch, as required for merchantable petroleums, and as ‘supplied: with: Now 3010 oid ae ato.c6 ogou Gey tog cin bund hele ee an bo 24.00 Tintometer Cell only, 75-inch, as required for Intermediate, Russian and Lubricating Oils, and as supplied with No. 3771.............. 7.50 Tintometer, Wesson, for Cotton Seed Oil, consisting of metallic observation instrument on tripod, with three glass tubes 6 x 7<-inch diameter for containing sample for test, and 27 Lovibond Standard Glasses as fol- lows: one each Red .1, .2, .3, .4, .5, .6, .7, .8, .9, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, and one each Yellow 1, 2, 4, 6, 8, 10, 20 and 35...... 62.75 Note—In the improved instrument the centers of the color discs are approximately only }-inch apart, permitting much closer readings, and by the use of special 6-inch tubes made of very thin glass, the errors due to thickness of bottles and variations in the color of bottle glass are entirely eliminated. Set of 27 Lovibond Standard Glasses, as supplied with Wesson Tinto- TRC UCD 5) cs Roath cca a tented eyhlery PONS Seedy ahs hoe prrecestiad 2 GU ue nod bk deere 47.75 Glass Tube only, 6 x 7¢-inch, as supplied with Wesson Tintometer.... 90 Colorimeter, Stammer, with metallic tubes and plungers 260 mm high as used in sugar analysis for grading syrups, and estimating the decolorizing power of bone black and other clarifying agents, and for many other purposes for which the degree of color, and not determination of color- producing substance, is desired. With four standardized colored glass plates. A solution which matches a standard plate for a scale reading of 1 mm is given a color value of 100, so that the color value of any liquid is found by dividing 100 by the reading on the scale in milli- MMOUCTS 8g hick wrckth ely ae ee Nt os fe ye eens en eka slides us 125.00 Set of Standardized Colored Glass Plates, only, for use with Stammer Colori- meters (Pen SEUOE LOUN, «4 :cncscssacemie atelier 1s cua Aoecomys ene ent 10.00 162 OM” (Po As ON) -Y THE COLORIMETRIC DETERMINATION OF HYDROGEN-ION CONCENTRATIONS (For the electrometric method, see page 243) _ The convenience and Telative precision with which the Hydrogen-ion concentration of solutions can be colorimetrically determined with the use of certain indicators and standard buffer solutions has led to wide use in laboratory work in the study of many physiological processes, of the activation of enzymes and of the growth of bacteria. : In this latter field, the method has already become standard for the control of the true reaction of culture media. See Clark and Lubs, Journal of Bacteriology, 2: 1, 2, 3 (1917). A recent and comprehensive discussion of the whole subject from both the theoretical and practical standpoint is to be found in “The Determination of Hydrogen-ions,” Dr. W. M. Clark, Baltimore, 1920. REGS \ wt \ me T_T (itt) (hit iin) (nn METHYL| | BROM-| PHENOL] |CRESOL| [THYMOll |PHENOL RED | |CRESOL| RED | | RED | | BLUE|| |PHTHA- BLUE | |PURPLE (alkali) | | LEIN [ART.CO Laut co. | AH.T.CO, || AHT co._| AH.T CO. | | AH.T CO f AH.T.CO. |) luni om i} oD CHU TT TTT LMT CILMI. CITT DB} Eo ni Set of Clark and Lubs Indicators, standardized dry powders INDICATORS, CLARK AND LUBS. A set of indicators covering the important zones of pH, carefully selected for their brilliancy, and which are relatively unaffected by conditions other than Hydrogen-ion concentration. such as salt and protein errors. The Thymol Blue of this series is a three-color indicator, recommended for differential titrations; see Clark and Lubs, Journal of the American Chemical Society, Vol. 50 (1918). The Brom Cresol Purple covers prac- tically the same range as litmus, and is more brilliant and reliable. The author’s technique for the preparation of stock and test solutions from these dry powders is as follows: ‘“‘For the preparation of these stock solutions one decigram (0.1 gram) of the dry powder is ground in an agate mortar with the following quantities of N/20 NaOH. When solution is complete, dilute to 25 ml. N/20 NaOH | N/20 NaOH Molecular Weight Indicator per decigram Molecular Weight Indicator per decigram 354.17 Phenol Red 5.7 ml 466.30 Thymol Blue 4.3 ml 669.82 Brom Phenol Blue 3.0 “ 624.12 Brom Thymol Blue See 382.17 Cresol Red 5.3 “ 269.12 Methy] Red Cea 540.01 Brom Cresol Purple Bet If there be no particular reason to maintain exact equivalents, it may be found easier to dissolve the dyes in 1.1 equivalent of alkali instead of one equivalent as indicated above. When made up to 25 ml, as noted above, there is obtained in each case a 0.4 per cent. solution of the original dye itself. For tests they should be diluted further. For use in testing 10 ml of a solution with five drops of indicator solution good concentrations are 0.04 per cent. for thymol blue, brom thymol blue, brom phenol blue, and brom cresol purple; and 0.02 per cent. for cresol red, phenol red and methy] red. Methyl red may be more conveniently prepared for the tests by dissolving one decigram in 300 ml alcohol, and diluting to 500 ml with distilled water. Ortho cresol phthalein and phenol phthalein are used in a 0.02 per cent. solution in 95% alcohol. (Clark, “*The Determination of Hydrogen-ions,” p. 66.) Other indicators are listed in the Reagent Section of this catalog. STANDARDIZED DRY POWDERS (Hynson, Westcott & Dunning and Lamotte) Common Name pH range Chemical Name Per 0.1 gram Per 1 gram Thymol Blue—acid range 1.2—2.8 Thymolsulphonephthalein...................... .25 2.00 Brom Phenol Blue 2.8—4.6 Tetrabromphenolsulphonephthalein.............. 25 2.00 Methyl Red 4.4—6.0 Orthocarboxybenzeneazodimethylaniline.......... .20 85 Brom Cresol Purple 5.2—6.8 Dibromocresolsulphonephthalein................ 25 2.00 Brom Thymol Blue 6.0—7.6 Dibromthymolsulphonephthalein............ .25 2.00 Phenol Red 6.8—8.4 Phenolsulphonephthalein....... f .25 2.00 Cresol Red 7.2—8.8 o-Cresolsulphonephthalein...................... .25 2.00 Thymol Blue—alkaline range 8.0—9.6 Thymolsulphonephthalein............ .25 2.00 Phenol Phthalein 8.4—9.2 Phenol Phthalein...... Sr rink aero aan .20 .70 Cresol Phthalein —_——— Cresol Phthalein........ .25 .70 LAMOTTE STANDARDIZED INDICATOR SOLUTIONS. We also offer the test solutions, ready for use, prepared in the concentrations and by the methods recommended by the authors. They are distributed in sterile, sealed ampoules and in sterile, sealed, glass-stoppered bottles, and are ready for immediate use either with the standard buffer solutions as listed below, or for use in the determination of Hydrogen-ion concentration by methods other than such as require the use of buffer solutions, for example, by the method of Louis J. Gillespie, Journal of the American Chemical Society, 42: 4 (April), 1920; in the study of soil reactions, KE. T. Wherry, Journal of the Washington Academy of Science, April, 1920; and for the determination of the Hydrogen-ion concentration of culture media, Clark and Lubs, Journal of Infectious Diseases, 117 (1915). 163 if i BUFFER SOLUTION It STANDARDIZED i KCL-HCL . BROMTHYMOL BLUE | lr STANDARDIZED ! i SOLUTION 0.04 Percent itll SS ARTHUR H.THOMAS Co. ee Plain Ampoule Tubulated Ampoule Standardized Indicator Standardized Buffer Solution Solution LAMOTTE STANDARDIZED INDICATOR SOLUTIONS (Continued) Per 10 ml Per 10m! Per 500 ml Common Name Concentration plain ampoule tubul. ampoule g-s-b. Thymol Blue (acid range) 0.04% aqueous..................0-. Pea 50 .60 3.10 Brom Phenol Blue 0.04% Fa eee Setb cH AG Be VEE AAS Poh IOE ak. a a RES 55 65 3.15 Methyl Red 0.02% et hanes thei BGA hea anes iad oes eS 45 55 3.05 Brom Cresol Purple 0.04% RES BAD) site tba ate Aa fe ev TOI Saar arate : 55 .65 3.15 Brom Thymol Blue 0.04% hich e get fol Se Oe MEIN SEN Oe BATS .60 .70 3.20 Phenol Red 0.02% e StS ES CUE ane ecg Ae ES eae 50 .60 3.10 Cresol Red 0.04% = 2S eke eae ea aha Ard ahh ies A ea 50 .60 3.10 Thymol Blue (alkalirange) 0.04% Spee eek aie Lemay tao ery as wa RU tea 50 .60 3.10 Phenol Phthalein OO 2G AVGOWOL) a 5ash oe 8 Pek aiedeln chia We teaehe ees -40 -50 3.00 LAMOTTE STANDARDIZED BUFFER SOLUTIONS, NORMALITY M/5 Standardized Buffer Solutions, Clark and Lubs. These standardized solutions are of such well- defined compositions that they can be accurately reproduced, and with pH values accurately defined by hydrogen electrode measurements. They consist of mixtures of some acid and its alkali salt. The care and accuracy required in the preparation of these standardized solutions in the laboratory has developed a demand for dependable solutions ready for immediate use. They are supplied in sterile, sealed, glass-stoppered bottles. For precise directions as to preparation of these solutions in the laboratory, we refer to Clark and Lubs, Journal of Biological Chemistry, 25: 3 (1916); and Journal of Bacteriology, Vol. 2, p. 25 (1917); and ‘‘The Deter- mination of Hydrogen-ions,” by Dr. W. M. Clark, Baltimore, 1920. Suitable reagents for the preparation of these and other buffer solutions are listed in the Reagent Section of this catalogue. For mixtures Per 500 ml Per 1000 ml Name of pH range g.s-b. g.s.b. Potassium Chloride Solution oa ORD. vas iy wee pauls ae Wee Eee ee 3.75 5.25 Acid Potassium Phthalate Solution DDE ONO an soi Rah coy haps Saeco Dae a 4.20 5.75 Acid Potassium Phosphate Solution OBO eth oewety Bins bah apiNd dak Gantaeae Gea 3.80 5.40 Boric Acid Potassium Chloride Solution CON O oe tole oooh ondes Secs eta 4 see gape menes 4.00 5.50 Sodium Hydroxide Solution (CO, free) eee 4.00 5.00 Hydrochloric Acid Solution eee 3.25 4.50 Boric Acid Solution sh ea RNS OA OES Soe ee, A pr aoe 3.25 4.50 Disodium Phosphate Solution 2 eee 3.75 5.25 LAMOTTE STANDARDIZED BUFFER MIXTURES Standardized Buffer Mixtures, Clark and Lubs. These are the mixtures prepared by adjusting a standard buffer solution to any desired pH from 1.2 to 10, in increments of 0.2 pH, by the addition of the required acid or alkaline salt, as given in Table 6, p. 75, “The Determination of Hydrogen-ions,’ Dr. W. M. Clark, Baltimore, 1920. These mixtures become color standards by the addition of the necessary indicator solution. We offer them in sterile, sealed ampoules of 10-ml capacity, both plain and tubulated, in sets of not less than 10 ampoules covering any specified pH range; or in sterile, glass-stoppered bottles of any desired pH. The range mostly used in bacteriology is from pH 6.8 to pH 8.4. In sets of ten plain ampoules, 10 ml each (pH range must be specified with order). Per 10 ampoules In sets of ten tubulated ampoules, 10 ml each (pH range must be specified with order). Per 10 ampoules. 3.50 In 1000-ml glass-stoppered bottles (pH range must be specified with order). Per bottle................ 8.60 LAMOTTE COLOR STANDARDS Color Standards. These are made of the standardized buffer mixtures with the addition of the necessary indicator of the Clark and Lubs set, to show the standard color at any desired pH from 1 to 10 in increments of 0.2 pH. These standards are in sealed, plain ampoules of 10-ml capacity and about 15-mm diameter, for con- venient use in any ordinary color comparator, and particularly with the Lamotte Hydrogen-ion Outfit as listed under No. 3797. They are supplied in sets of not less than ten ampoules, covering any range desired; the set mostly used in bacteriology being Phenol Red pH 6.8 to 8.4. In sets of ten plain ampoules, 10 ml each (pH range must be specified with order). Per10 ampoules 4.05 164 A R T H U_R H. T H O M A _S Cr SO EM RP. A ON UY : THE SPOT METHOD for Determination of Hydrogen-ion Concentration of Culture Media and Other Solu- tions. The tubulated ampoules listed on preceding page, in which the delivery tip is slightly curved and a tubu- lation is provided with rubber bulb with which to control accurate drop by drop delivery, were specially designed for convenient use in the ‘‘spot”” method, which has been found invaluable when only a small amount of the solution is available, as, for example, the study of tissue cultures, in vitro; or when highly colored solutions are to be roughly checked. The principle involves the direct comparison of the color produced by mixing a drop of the “‘unknown”’ solution and a drop of the proper indicator, with the colors resulting from mixing a drop of the standard buffer solution with a drop of the same indicator. The actual examination is carried out as follows: a drop of the solution to be examined is mixed with a drop of the proper indicator on a piece of opal glass. Around this are placed drops of the standard buffer solutions and with each drop of buffer solution is mixed a drop of the same indicator used with the ‘‘unknown.” The spots thus produced will exhibit colors varying in shade with their H-ion concentrations, and by carefully matching the color of the unknown solution with the known buffer spots, the pH value may be directly ascertained. Because of the rapidity and simplicity in operation, it is possible with this method to make a large number of determinations in a minimum of time. Using ampoules which give drops of nearly uniform size, the accuracy then depends upon the operator’s ability to differentiate between the grading colors on the plate. See Lloyd D. Felton, A Colorimetric Method for Determining the Hydrogen-ion Concentration of Small Amounts of Fluid, The Journal of Biological Chemistry, 46: 2 (April), 1921. 3792. Opal Glass Plate, with neatly ground edges. Convenient for use as a background in colorimetric comparisons, and for the spot method of determining hydrogen-ion concentration. IS1ZEss IM CHES fo re te RIAN) oe ea Ns eae ee Ne ONS caret Oth ect an Goad ea Ae apes Aka Ber tte 4x8 12x12 Ria eRe a tee cots fone Reta tint Ae dened Ur pede -50 1.00 jis: it | tl i | | | it I | eau 3797 3793. Color Comparator, Army Medical School Model, for use with ampoules or test tubes of not over 15-mm diameter in the colorimetric determination of hydrogen-ion concentration. Of hard wood, fin- ished in dull black. With two observation holes....... Re CN eat eae get 50 3794. ditto, Clark Model, with three observation holes............0..0 0.0000 cece eee ete eee nee 75 3795. ditto, Gillespie Model, with two observation holes, but for the use of paired (acid and alkali) color standards. See Journal of the American Chemical Society, 42: 4 (April), 1920...... 75 3796. Indicator Field Set, Lamotte, for determining the acidity and alkalinity of soils, as used and described by E. T. Wherry, Journal of Washington Academy of Science, April, 1920, and Rhodora 22-1920. Pocket size case containing six indicator solutions (pH 3.0 to 9.8), with droppers, two extra empty vials without droppers, directions for use and table showing classification of soil reactions and indicators in terms of specific reactions, pH values, and descriptive terms for typical soils. The six indicators furnished are brom pheno! blue, methyl] red, brom cresol purple, brom thymol blue, phenol red and cresol phthalein.......... 0.00. eens 4.10 3797. Hydrogen-ion Set, Lamotte, consisting of a Lamotte comparator and tube rack of wood, ten standardized color tubes (plain sealed ampoules as listed on preceding page), two extra graduated test tubes of the same diameter as the ampoules, approximately 15 mm, for examination of the unknown solution; one 1-ml pipette for measuring the indicator solution, one ampoule standardized indicator solution and one ampoule of distilled water. This set can be furnished with the ten standard color tubes cover- ing any desired pH range, or with any desired standardized indicator solution, if specifications are supplied with order. For bacteriological work, the set is mostly supplied with the ten standard color tubes of phenol red, pH range 6.8 to 8.4, and with one tube phenol red standardized indi- cator solution for addition to the unknown. The special 1-ml pipette is conveniently provided for in the lid of the comparator, and the opening in the block permits simultaneous observation of three tubes. Complete with directions for use............ edt ria rue See Cire PA pena regs 8.75 3798. Graduated Pipette, only, | ml, for use in above set. eigen Sees. Pm Steet ee .80 3799. ee Test Tube, only, for use in above set............ ; pas he 5 165 STANDARD WITH INDICATOR WATER jaan Lo t t cofenea aso \ RACK FOR /STANDARDS d ! wl ' UNKNOWN WITHOUT, eo UNKNOWN WITH INDICATOR Tetee ok INDICATOR EYE 3800. Fig. 1 3800. Fig. 2 COLOR COMPARATOR, Cooledge, for the convenient comparison of a series of unknowns with a graduated series of liquid color standards, as used in the colorimetric determination of H-ion concentrations with Clark & Lubs Indicator Set. The comparator consists essentially of two hardwood test tube racks, mounted in a track in a hardwood support block which contains the operating devices. The arrangement of the standard and unknown tubes at the time of comparison is the same as in the comparator described by Hurwitz, Meyer and Ostenberg (Bulletin, Johns Hopkins Hospital, 27: 16, 1917) with holes for the Walpole (Biochemistry Journal, 5: 207, 1910) combination for use when dealing with turbid or highly colored solutions where color comparison is impossible without special equipment. The test tube racks are 24 inches long and contain 12 holes each 74-inch diameter for holding test tubes containing the standard and unknown liquids. As the rear rack is used for the standards, it has a cord arrangement with which it may be rapidly moved to the correct standard. The front rack holds the unknowns, which are moved the distance of only one tube each observation by means of a hardwood knob on the back of the instrument. The racks are provided with a catch system so that the tubes are always brought exactly opposite their proper observation window. The comparator may be directly illuminated by an electric lamp at the rear of the device, or by light reflected from a white object appropriately placed. With trestle support, on which to use the comparator for the purpose of supporting the instrument at a suitable height above table (about 12 inches) for convenient observation. 3800. Color Comparator, Cooledge, as above described, on trestle support but without test tubes....... 12.50 3801. ditto, but without trestle support, on small feet.......00.0.00 00000. ee ... 10.00 3802. Trestle Support, only, for above comparator.............. on ont inh inst ARs ween nh alata yn here 2.50 3803. Braided Silk Cord, for replacement. Percard.................... een SURO ane Gurr Rate Seen ante -50 Parcel post shipments are made three times daily. Above illustration shows parcel post packages as prepared for domestic shipment. 166 A R T H U R H. T H O M AS Cc O M P A N_Y COMBUSTION TRAINS FOR THE DETERMINATION OF CARBON IN STEEL BY THE DIRECT COMBUSTION METHOD. One of the most important analyses in steel work is the determination of carbon and this, until recent years, was done by the Eggertz or color method. This has now been practically discontinued on account of the time required to make the test, liability of error, ete., and has in most laboratories been superseded by the more accurate, rapid and convenient method by direct combustion. In direct combustion the sample, preferably in the milled form, is ignited in a current of oxygen, usually by means of an electric tube furnace, the carbon is oxidized forming CO» which is absorbed in a suitable container, the container being weighed before and after the ignition. By using a factor weight for the sample, computation can be made rapidly and results are accurate. As the principle and method used in all trains is practically the same, the following important points should be considered: Pure oxygen in high-pressure cylinders should be used. A suitable reducing valve is necessary and while some chemists consider the reducing valve only as sufficient, others prefer to use the reducing valve with a gas holder or aspirator bottle (see illustration of Stetser and Norton Train). The Linde Oxygen has been found to be free from CO, and while some do not consider it necessary to use any purifying vessel, driving the gas directly into the train, it is recommended that for accuracy a drying tube and absorption vessel be used. If a gas washing Polls filled with 50°, Potassium Hydrate Solution is used, the bubbling of the gas passing through will indicate the flow. A Mercury Pressure Gauge such as used in the Fleming Train, or a Mercury Gauge and Safety such as used in the Vanier Train, should be placed ahead of the purifying vessels to serve as a guide during the com- bustion, as it is essential that a free flow of oxygen at a constant pressure be fed to the train. A Mercury Valve is used directly in front of the combustion tube as an additional precaution to insure an atmosphere of pure oxygen reaching the sample. Combustion Tubes of silica and clay are mostly used. It is essential for the complete oxidation of the 40-mesh sieve have been found to work very satisfactorily. The container for the sample is a combustion boat of clay, nickel, alundum, porcelain or platinum, those of alundum and clay being in principal demand because they are inexpensive, and many combustions can be made before they become useless. The boat is protected from the sample by means of a layer of alundum or some other similar material,—the RR Alundum, alkali free and free from carbonaceous matter, being recom- mended. It is necessary, however, to ignite both the boat and protection material for some time prior to the test to be sure that they are free from carbon. Electric Furnaces, either of Hoskins or Multiple Unit manufacture, as described hereafter, are recom- mended, as these have a safe working temperature of 1000° C, which is the correct temperature for the ignition. A rheostat should be used as the temperature should be kept constant at 1000° C, and not be permitted to fall below 960° C. For the exact regulation of the temperature, a Pyrometer is found convenient although a practiced eye can approximately estimate the temperature. Some loosely packed asbestos, preferably preceded by a small amount of platinized asbestos, is placed in the exit end of the combustion tube to serve two purposes; in the hot zone it acts as a catalyzer and insures com- plete oxidation of carbon monoxide to carbon dioxide, while at the extreme end of the tube it prevents radiation of heat. At the exit end of the train it is the usual custom to have three vessels, one containing a small quantity of granulated zinc, either 20 or 30 mesh, to be used as a filter and to remove oxidized sulphur, a drying vessel containing either sulphuric acid or phosphorus pentoxide and the absorption vessel for absorbing the CQ». General Method of Operation. A depression in the shape of a ‘‘V” about one inch long is made in the refractory material contained in the combustion boat, and one gram or a convenient factor weight of the sample, depending upon the manner of absorbing the carbon dioxide, is placed therein. To protect the silica tube from spattering when the sample is ignited, some chemists cover the drillings slightly with the refractory. The furnace having been brought to the required temperature, the boat is inserted halfway in the tube and all precautions having been taken that the connections are gas tight, the oxygen is admitted at a uniform rate, depending upon the judgment of the operator and depending upon the absorbent used—if a liquid absorbent, a continuous bubbling is observed. In the course of a minute, the steel will begin to oxidize and the rate of bubbling in the absorption vessel will decrease. When the steel is completely oxidized a sudden acceleration of the bubbling will occur. At this point, in order to completely expel the carbon dioxide from the combustion tube, the rate of flow of oxygen is regulated, depending upon the absorbent used. The absorption vessel is then disconnected, the current of oxygen discontinued and the analysis concluded by the weighing of the absorption bulb and computing the result by the gain in weight. The absorption tube is then replaced on the train, a current of oxygen is passed through to complete expulsion of air, the bulb is then re-weighed and is ready for the next analysis, or if determinations are made in rapid succession, this is unnecessary, as the final weight of the last combustion can be taken as the initial weight of the succeeding. VANIER COMBUSTION TRAIN. The train illustrated on page 168 is. with some modification, the original equipment introduced_by Mr. George P. Vanier, Chief Chemist, Steelton Plant, Bethlehem Steel Com- pany. The absorption bulbs E, F and G were designed especially by Mr. Vanier for this train. The paramount feature of the outfit is the Vanier Combined Potash Bulb and Drying Tube G, (patented July 30, 1912, No. 1,034,170) which is used in many prominent steel works laboratories throughout the country. This outfit only includes glassware which is considered absolutely necessary, and with this train determinations can be made with results are accurate. seis te Oubae consists of the following: Hoke-Phoenix Gas Pressure Regulator; Mercury Gauge and Safety A to allow measuring the pressure up to two inches of mercury (any excess pressure allows the oxygen to escape without blowing the mercury out of the gauge); Calcium Chloride Tube T, filled three-quarters full with finely divided calcium chloride, about 12 mesh, with a layer of asbestos over the calcium chloride and the remaining space filled with soda lime; Mercury Valve V, to prevent recessions; Electric Combustion Tube Furnace C, Com- bustion Tube D; Zinc Tube E for acid fumes, Sulphuric Acid Bulb F, and Potash Bulb and Drying Tube G for absorbing the CO>. Method of Operation. Open the stopcocks on bulbs #, F and G, and start a rather rapid flow of oxygen through the apparatus. The flow should then be gradually reduced by means of the stopcock on the Sulphuric Acid Bulb, so that 1 liter of gas passes in from 15 to 20 minutes. The Mercury Gauge should now show 1} inch pressure, or a slight excess of oxygen bubbling through the gauge. If the pressure is below 1{ inches, increase the flow of oxygen. If the oxygen is escaping through the gauge, decrease the flow of oxygen until the gauge shows 167 3820 Vanier Combustion Train VANIER COMBUSTION TRAIN (Continued) 13 inches pressure. Having adjusted the stopcock on the Sulphuric Acid Bulb so the above conditions prevail, it is to remain adjusted and not disturbed. The oxygen can now be shut off at the Hoke-Phoenix Regulator, or at the tank, and all is ready for the combustion. Place 2.7273 grams of steel in the combustion boat, having partly filled same with alundum, and cover with a slight sprinkling of alundum. The boat is then inserted into the tube, the stopper inserted and the oxygen turned on until the gauge shows 1 inches pressure. As soon as the steel begins to burn, the gauge will begin to show less pressure and the flow of oxygen should be increased, keeping the gauge pressure at 12 inches, or have the oxygen bubbling slowly through the gauge. After the steel is burned (in from 3 to 5 minutes) the flow of oxygen should be decreased so that the gauge shows 1# inches pressure, or in other words, during the combustion manipulate the flow of oxygen so the mercury gauge and safety always show a constant pressure of 13 inches. In 15 or 20 minutes shut off the oxygen and close the stopcock on the Combined Potash Bulb and Drying Tube. Remove and weigh this bulb. Each milligram represents 0.01% carbon. After weighing connect the Combined Potash Bulb and Drying Tube to the train, and all is ready for another combustion. The apparatus is entirely automatic and requires no attention while the combustion is going on. For instructions regarding the filling of the Vanier Combined Potash Bulb and Drying Tube, see page 172. The Vanier Combustion Train, as above illustrated, consists of the following (all listed elsewhere in the catalogue): 5977. Gas Pressure Regulator, Hoke-Phoenix 9336. Support, with rectangular base, 4 x 6 inches 3898. Mercury Gauge and Safety A 3220. Clamp, with double jaws 9756. Glass Y-tube, 5 mm bore 6068. Glass Rod, 12 by 3-inch diameter 2714. Calcium Chloride Jar T, size 315 x 45 mm 8810. Rubber Stoppers, for mercury valve and safety Bent Glass Tube for connecting calcium chloride jar calcium chloride jar and combustion tube to mercury valve 8834. Rubber Tubing, ;;-inch bore, for connections 3895. Mercury Valve V 5798. Combustion Tube Furnace, Multiple Unit Electric, 3896. Vanier Zinc Tube E Type 77, with selective winding for 110 or 220 volt 3897. Vanier Sulphuric Acid Bulb F current, without rheostat 3840. Vanier Combined Potash Bulb and Drying Tube G 5800. Rheostat for 110-volt current 3888. Johnson Vitrified Clay Combustion Tube D, 23} inches long by 3-inch bore 3820. Combustion Train, Vanier, complete as illustrated and described above, with rubber stoppers, glass tubing and rod, and with Multiple Unit Electric Combustion Tube Furnace and Rheostat for ASO VigltS pastes ers 43 aie ne pos mteelin st baci a a pik SM ome he tee ass hh bay ate megs tcp cn a ay le ae aan oebiae ... 92.50 3821. ditto; but‘ with Rheostattor 220 Voltst. eos. sao .2 cho ca dita gue gh sed oe ugeeen as ned nonaalinle sh gee ees 92.50 3822. ditto, but with Hoskins Electric Combustion Tube Furnace, Type FDH 302, and Rheostat for MSL OUVOLES anes eee rants bts curs se Wale deere pena: Samia mel ela MR Ml Eten g dete arts emcees Aas oan ... 92.50 3823. ditt, but with Rheostat for: 220 VOlts ng ws deh oe cea a. 2 Mat eS Eon ahs dk bens Fak oh os 92.50 FLEMING COMBUSTION TRAIN, designed by Mr. Wm. R. Fleming, Chief Chemist, Andrews Steel Company, Newport, Ky., was originally described in an article entitled “Rapid Determination of Carbon in Steel,’’ in The Iron Age, January 2, 1913, and a more detailed description of the outfit published in The Iron Age, Janu- ary 1,1914. For particulars not mentioned below, we refer to these articles. The feature of this train and the method used is the rapidity with which combustions can be made, the author having in six hours made 42 determinations on a standard steel containing 1.025% carbon. Only one combustion train and one absorption bulb were used. The item of principal interest is the special absorption bulb W of the illustration. In this bulb soda lime and phosphoric anhydride are used (for further details regarding the bulb see page 172). : : ; The Fleming Train consists of the following parts; oxygen being delivered from a high pressure cylinder by means of the regulating valve: K is a mercury pressure gauge, which serves as a guide during the combustion and is an essential piece of apparatus. The graduated column is 6 inches high, and is divided into 3-inch divisions. P is a washing bottle containing 50% potassium hydroxide solution. One filling will last for at least 1000 combustions. It is used to indicate the flow of gas. T is a calcium chloride jar filled approximately two-thirds full with finely divided calcium chloride about pea size, a layer of asbestos over this, and the remaining space filled with soda lime. The glass tube leading 168 3824—Fleming Combustion Train FLEMING COMBUSTION TRAIN (Continued) from this jar to the mercury valve V should be packed loosely with asbestos for several inches to prevent any soda lime dust from being carried into the combustion tube. M is a mercury valve used to maintain an atmosphere of pure oxygen in the tube. It is not used to prevent carbon dioxide backing into the purifying train, of which there is not the remotest possibility. D is a glazed vitreosil combustion tube—a tube 30 inches long by 72-inch bore being recommended. This is packed with asbestos for a distance of 6 inches at the exit end, and projects 3 inches from the furnace. During the first 100 combustions the boat is pushed close against the asbestos. The portion of the tube immediately above this will become coated with iron oxide. The asbestos is then moved up so that it covers this portion of the tube and a fresh area is exposed to the spraying oxide. In this manner, one tube can be made to serve approx- imately 600 combustions or more. F is the combustion furnace, usually the Hoskins or Multiple Unit type, maintaining a temperature of 1000° C. C is a two-way stopcock, which is found convenient when it is not desirable to pass the current through jars Z and O. : Z is a zinc jar filled with 30-mesh zinc, which once filled will last for several thousand combustions. It is intended as a filter and to stop any fumes which might result from a fly getting into the combustion tube. O is a phosphoric anhydride Jar, a little asbestos being placed in the lower part just above the lower stop- per. The remaining space is filled with phosphoric anhydride. The upper stopper is packed tightly enough to prevent any powder being swept into the weighing apparatus. As the anhydride liquifies, it passes down into the lower stopper, where it can be removed conveniently without disturbing the anhydride above it. Likewise, the anhydride can be replenished by removing only the upper stopper. The jar need not be refilled more often than once in 500 combustions. When filled with anhydride, fresh reagent need not be added for at least 150 combus- tions. After each combustion, the jar should be given a few sharp taps to prevent the formation of canals. W is the Fleming Absorption Bulb, which when properly filled will last for at least 70 combustions, oper- ating on 1.5 grams of sample containing 1.03% carbon. The phosphoric anhydride in the upper chamber serves for at least 300 combustions. The soda lime, containing 2% moisture in 20, 40 and 60 mesh, is used in the lower compartment, the material being placed in the tube in alternate layers about s-inch thick, the different meshes having proven to be a very convenient and desirable reagent. The lower stopper is packed loosely with asbestos, also the lower portion of the soda lime chamber just above the stopper. The small diameter of the anhydride chamber is packed with asbestos, and the remaining space filled with phosphoric anhydride. The upper stopper is also packed with asbestos. It is recommended that the bulbs be used in pairs, so one serves as a tare in weighing the other. A pair of bulbs assures the operator of at least 140 combustions. P1 is a bottle filled with potassium hydroxide, and is used to indicate the flow of gas. Clay, alundum or nickel boats may be used; the author recommends nickel boats which should be burned in oxygen before using. Details of the Analysis. The various vessels having been filled and connected properly in their place, and the furnace being brought up to the required temperature, i. e., 1000° C, two freshly prepared absorption bulbs are placed in the train and oxygen run through at the rate of 300 ml per minute for 15 minutes. This insures the displacement of all air from the purifying train, as well as the absorption bulbs. One absorption bulb is then removed, and the oxygen is turned on until the mercury stands at about 2 inches. The rate of current is then measured by inverting a graduated cylinder filled with water. Several trials will establish a rate of about 325 ml per minute. The reading on the mercury column should be noted at this rate, and subsequently, when using the same absorption bulb, maintain the same pressure in the train and the rate of flow will be 325 ml per minute during all combustions. Shut off the oxygen, and when it comes to a slow bubbling through P! close the upper stopper of the absorption tube. Disconnect it from the train, but do not close the lower stopper for about five seconds after disconnection. , fen : ; : Weigh 1.5 grams of the sample, preferably thin curly drillings from a twist drill and spread out in the boat which is half filled with alundum. Place the absorption bulb in the train, and its mate beside it. With the oxygen flowing about 100 ml per minute, the drillings are pushed into the combustion tube. The current is immediately run up to the desired pressure, which gives 325 ml per minute—the regulator will do the rest. It will feed the oxygen automatically to the burning steel. As a rule, the drillings are entirely burned one and one-half minutes after insertion. Continue the flow of oxygen for three and one-half minutes more, making a total of five minutes, and disconnect the absorption bulb as before. Weigh immediately. The result will be accurate and reliable. Whether determining the carbon in standard steel, where the greatest accuracy is required, or in a bath test, the time required for the operation is about five minutes. 169 AY RO A ow oR H. T H O M AS C O M P A N _ Y FLEMING COMBUSTION TRAIN (Continued) The Fleming Combustion Train, as illustrated on preceding page, consists of the following (all listed elsewhere in the catalogue): 3893. Mercury Pressure Gauge, part K 6080. Glass Tubing, 6 mm, for making connections 5992. Gas Washing Bottle, part P 8834. Rubber Tubing, {-inch bore, for making connections 2714. Calcium Chloride Cylinder, 315 x 45 mm, part T 8810. Rubber Stopper, No. 7, one hole, for CaCl cylinder 3895. Mercury Valve, part M 8810. Rubber Stopper, No. 5, one hole, for Zine Jar 3885. Silica Combustion Tube, glazed, 30x { inches, 8810. qupber Stoppers, No. 4, one hole, for Combustion part D ube 3894. Stopcock, part C 5798. Combustion Tube Furnace, Multiple Unit Electric, 3891. Zine Jar, part Z Type 77, with selective winding for either 110 or 3892. Phosphoric Anhydride Jar, part. O 220 volt current, without rheostat 3842. Fleming Absorption Bulb, part WW 5800. Rheostat, for 110-vo!t current 5992. Gas Washing Bottle, part P' 3824. Combustion Train, Fleming, complete as illustrated and described with rubber stoppers, and glass tubing and with Multiple Unit Electric Combustion Tube Furnace and Rheostat, for 110 volts.... 68.50 3825. ditto; but-with. Rheostat for 220: Volts... ind ecg nob Saad men ois wae haeeido Gisek Baga Sede ae eae 68.50 3826. ditto, but with Hoskins Electric Combustion Tube Furnace, type FDH 302, and Rheostat, for TRO MOLES ae ceca ree toa es Se seen eto, eae ew Eide cA ret Ano AA ors RN ea led SoA bc hired 68.50 tmnt | 3828 nh R Stetser and Norton Combustion Train STETSER AND NORTON COMBUSTION TRAIN. The train illustrated above was described in an article entitled ‘‘Combustion Train for Carbon Determinations,” by J. B. Stetser and R. H. Norton, in The Iron Age, Vol. 102, No. 8. Reprint of this article will be sent on request. The special features of this outfit are, rapidity with which combustions can be made, simplicity of the absorption bulb, and the use of ‘“Ascarite,” a special sodium hydroxide asbestos absorbent mixture, according to the formula of Mr. J. B. Stetser. The bulb is a modification of the Midvale Absorption Bulb designed by Mr. H. L. Fevert, of the Midvale Steel Company, and with one filling can be used for at least 400 determinations, using one-half factor weight with carbon 0.50%. The bulb measures 45 mm diameter at its widest portion at the bottom, and 120 mm high over all. It is provided at the top with a capillary tube and rubber stopper (see No. 3851), or if so desired can be supplied with glass stopper (see No. 3852). With this train, the authors report having checked a standard in two minutes actual time, although the usual procedure is to allow three or four minutes for combustion. Results are often reported in six minutes after the sample enters the laboratory; this includes time for drilling, weighing sample, running test, weighing bulb and reporting result. 170 A R T H U R H. T H O M A § Cc O M P A N _ Y STETSER AND NORTON COMBUSTION TRAIN (Continued) The equipment consists of the following parts, the oxygen being delivered from a high-pressure cylinder through the gas pressure regulator (the authors also recommend that bottles as shown in the illustration be used to maintain a constant pressure): A is an aspirator bottle of 8 liter capacity, graduated by the user for each 250 ml. B is a green glass bottle, narrow mouth, 2 gallon capacity. C is a stopcock to prevent the gas from flowing through the train when turned on at the regulator. D is an 8-ounce, wide-mouth bottle which is empty and used as a safety. Eis a similar bottle filled 1/3 full with concentrated sulphuric acid. F is also a similar bottle filled with Ascarite. G is the usual Combustion Tube Furnace. R is the rheostat for controlling the temperature. J_is the Vanier Zine Jar filled with 30-mesh zinc. K is the Vanier Sulphuric Acid Bulb containing sulphuric acid. M is the Stetser & Norton Modification of the Midvale Absorption Bulb, which is filled with Ascarite. : _ Method of Operation. The train being set up and free from leaks, the stopcocks are open with the excep- tion“of the one on the Sulphuric Acid Bulb K. This is open sufficient to allow gas to flow at the rate of 200 to 250 ml{per minute when the absorption bulb is attached. The stopcock C is then closed, the remaining stopcocks being left as adjusted. The train is now ready for operation. Bottle B is filled with water, the gas regulator is opened, allowing oxygen to displace the water in bottle B, which water is driven into bottle 4; when bottle A is filled the regulator is closed and all is ready for the combustion. The exit end of the combustion tube, the usual glazed silica tube being recommended, is packed with some asbestos burned in a current of oxygen prior to using. A sample of one-half factor weight properly prepared and weighed is placed in the alundum boat, RR Alundum protection being used, and is then inserted in the furnace. The stopcock C is opened, and if the furnace is at 1800° F or over, and the sample of drillings fine and uncovered, it should begin to burn in 20 seconds. The burning should take 40 to 60 seconds additional, consuming 500 ml of oxygen. An additional 500 ml of oxygen is turned on to wash out all CO», and the bulb is then ready to be weighed. If the sample is covered by a lid, or RR Alundun,, or if the drillings are coarse, or the furnace is below 1800° F, the combustion may be delayed as much as two minutes. The actual burning will, as before, take from 40 to 60 seconds. In any case, 500 ml of gas must be passed through the apparatus after the steel has ceased burning. The point at which the burning of the sample begins may be determined by the increased rate at which gas passes through the liquid in bottle E, due to the rapid absorption of oxygen by the burning steel. A similar decrease marks the end of the burning period. Standardization of the Stetser & Norton Absorption Bulb. The method of filling the bulb is explained on page173. It should be noted that no dryer is used, the absorbent being its own dryer. A filled bulb should absorb from 10 to 15 grams of carbon dioxide. A freshly filled bulb should be run on the train for an hour and then weighed. It is not necessary to run the gas at a rapid rate during this time. The bulb is again attached and two more liters of gas are run through at the usual rate. The bulb should show neither gain nor loss. Should it do so, gas must be run through for an- other period of an hour. The bulb is then checked with two liters of gas. It should not, however, be necessary to run the bulb a second time. When the bulb has reached a constant weight, the train is checked by running a government standard. A fresh bulb may show slightly low results on the first three carbons. There is no danger of loss of CO. through the Ascarite, as it does not penetrate even at extreme speeds a depth of more than 1} inch, leaving the lower portion untouched. Ascarite, the sodium hydroxide asbestos absorbent used, being its own dryer, possesses advantages over the absorbents needing an extra dryer. It has the same drying power as a freshly filled Vanier Sulphuric Acid Bulb, and has large absorbing powers. A bulb once filled and standardized will last for several weeks, and is sufficient for from three to four hundred determinations. On account of the difference in color between the used and unused portions of the absorbent, it is possible to determine the moment a bulb can be discarded. Owing to the rapidity with which gas may be safely passed through, it prevents formation of carbon monoxide, insures complete combustion of all carbon and allows the accurate combustion of substances otherwise troublesome. It also prevents errors from small leaks. The simplicity of the method of operating the train and the method of measuring the gas used, which gives the exact instant. the bulb is ready to weigh, make this train well fitted for the use of chemists who have had no previous experience ir carbon combustion, besides allowing accurate results to be reported in the least possible time. The Stetser & Norton Combustion Train, as above illustrated, consists of the following (all listed elsewhere in the catalogue): 2202. Bottle, Green Glass, narrow mouth, 2 gallon ca- 6068. Glass Rod, 12 x } inch diameter pacity, with two-hole rubber stopper, B of illustra- 3896. Vanier Zinc Tube, J of illustration tion 3897. Vanier Sulphuric Acid Bulb, K of illustration 2236. Aspirator Bottle, 8 liter capacity, with one-hole 3851. Stetser and Norton Modification of the Midvale rubber stoppers, A of illustration Absorption Bulb, M of illustration 6080. Glass Tubing, 6 mm outside diameter, for connec- 1 Ib. Ascarite, a sodium hydrate asbestos absorbent tions mixture according to Stetser and Norton 9752. Glass T-tube, 3 mm bore 9336. Support, with rectangular base 4 x 6 inches 9287. Glass Stopcock, 2 mm, C of illustration 3220. Clamp, with double jaws 2204. Bottles, wide mouth, 8 oz. capacity, with two-hole 5798. Combustion Tube Furnace, Multiple Unit Electric, rubber stoppers to be used as safety bottles D, E Type 77, with selective winding for either 110 or 220 and F of illustration volts, without rheostat 3885. Silica Combustion Tube, glazed, 30 x { inches 5800. Rheostat, for 110 volts 3828. Combustion Train, Stetser & Norton, complete as illustrated and described above, with rubber stoppers, glass tubing and rod, and with Multiple Unit Electric Combustion Tube Furnace and Rheostat, POLLO VOLES ore. sare eras es er Be rarest Gophers Pos GRITS SE EN SS Gasoinae na Dea cutemneet sO : : 65.00 3829. ditto, but with Rheostat for 220 volts.............. 0... 65.00 3830. ditto, but with Hoskins Electric Combustion Tube Furnace FDH 302 and Rheostat for 110 volts 65.00 3831. ditto, but with Rheostat for 220 volts............ 6.0 eee eee eee ee 65.00 171 Ao Re A eR He. T H O M A 5 C O M P A N Y ABSORPTION BULBS FOR THE DETERMINATION OF CARBON IN STEEL BY THE DIRECT COMBUSTION METHOD = wand 3846 3848 As the essential features of the preceding combustion trains are mostly embodied in the various absorption bulbs required, we list and describe these items below. The other complements of the train are listed throughout the catalogue under their respective headings. Vanier Combined Potash Bulb and Drying Tube, designed by Mr. Geo. P. Vanier, Chief Chemist, Steelton Plant, Bethlehem Steel Company, patented July 30, 1912, No. 1,034,170. Six grams or more of carbonic acid can be absorbed, thus enabling the chemist to make over 100 combustions without refilling. No rubber caps are necessary when weighing with the bulb filled with oxygen, as the glass stopcock closes the inlet and outlet. Having a drying tube attached, they are compact and more easily handled than the ordinary bulbs. They have a smooth outer surface which is easily cleaned, are self-supporting and having a firm base can be conveniently placed on the balance pan when weighing. The drying tube being vertical, the moist gases pass in at the bottom and the drying tube never stops up. As the solid caustic potash deliquesces it forms a pool in the bottom of the drying tube, thus making an extra seal. The gases can be passed at a high rate without loss of CO: or moisture. When gases are passed through rapidly the action is perfectly quiet, without any spraying or jumping of the solution. 3840. Vanier Combined Potash Bulb and Drying Tube, as described above. ..............-..00000 005 6.00 Directions: To fill, remove stopper and glass stopcock. Fill drying tube two-thirds with dry caustic potash, size 5 to 10 mesh, and finish filling with from 10 to 20 mesh, placing a small wad of cotton or glass wool on top. With the aid of a small funnel pour a solution of caustic potash (1 lb. of caustic potash to 600 ml water) through side tubulation until it reaches the top of coil. Grease and replace stopper and stopcock. To empty, remove stopper, stopcock and wad. Slip a piece of }-inch rubber tubing (about 10 inches long) over side. Turn bulb upside down, holding in left hand, and with right hand grasp end of rubber tubing and hold under a faucet of running water, thus allowing bulbs to fill with water, then lower the end of the rubber tubing, allowing the water to run out. Repeat this operation of filling and emptying several times. Drain and dry, and bulbs will be ready for refilling. 3842. Fleming Absorption Bulb, designed by Mr. Wm. K. Fleming, Chief Chemist, Andrews Steel Company, for the absorption of CO, in the determination of carbon in steel by the direct combustion method. With this bulb, gas may be passed through at the rate of 400 ml per minute without any loss of moisture. At least 70 combustions may be made with one charge of soda lime, and when operating on 1.5 gram sample of 0.75% carbon steel, 300 combustions may be made with one charge of phosphoricsarihydrid es i2, sortie nateca wer teen Yar co a ye Ser ht Te eh scet of 0S coe ee bal Bo a 4.50 3844. Fleming Absorption Bulb, Martin’s Modification, with ground joint in the center. This bulb has an advantage over the original Fleming Bulb since it can be more easily manipulated in conjunction with the train and is also much easier to fill. ... 0... eee eee 5.00 Directions: The small diameter portion of the upper chamber as well as the upper stopper is packed with asbestos, and the remaining space is filled with phosphoric anhydride. One filling of phosphoric anhydride will serve for at least 300 combustions. Sodium Calcium Hydrate (Soda Lime) containing 2% moisture, in 20, 40 and 60 mesh size is used in the lower vessel in alternate layers of about } inch. The lower stopper as well as the lower portion of the soda lime chamber are packed loosely with asbestos. The tubes should be used in pairs so that one serves as a tare in weighing the other. A pair of tubes insures the operator of at least 140 combustions. Ascarite can be used in this bulb in place of the soda lime. 3845. Fleming Absorption Tube, Mercury Sealed, Patented. This bulb is automatically sealed and maintains a perfect atmosphere of oxygen. There are no inlet or outlet valves to manipulate as these are automatically operated by the mercury traps. For use with phosphorous pentoxide and soda TTT Coste Toate asta va Set ney entra ioe OS ere anes eae rer thee Be yan Moe UN ew ays kgs Ah an ye eeen ees 7.50 3846. Fleming Absorption Tube, Mercury Sealed, Patented, similar to above but with only one compartment ROP UISCHWILNAAS CATILC rt cea hema haea and ated airs tad oO guCT OE eben ieee fd tule pectin ten Satin wie een aaa gee 7.50 3848. Nesbitt Absorption Bulb, designed by Mr. C. E. Nesbitt, Chief Chemist, Carnegie Steel Company, for the rapid absorption of CO, in carbon determinations. This bulb can be charged in less than 5 minutes and weighs about 135 grams when filled. Using a 1.363 gram sample, more than 400 determinations can be made with one filling. A slight turn of the stopper closes both inlet and outlet-tubess:Sealin get he soul) rx avn wees oer gute wet S te Apes Se py ee peed wiolg Pi ehe me eat ad A 6.00 Directions: To fill, place a layer of glass wool about }-inch thick in the bottom, add about 60 grams of 12-mesh soda lime, 15% moisture, insert ;-inch layer of asbestos fibre, add 10 grams of P.O;, then another thin layer of asbestos and a thin layer of glass wool, filling the bulb to the neck. Fill the hollow stopper with cotton. Connect the charge so that the gas enters at the bottom and leaves at the top. Ascarite can be used in this bulb in place of the soda lime. 172 A 3850. 3851. 3852. 3853. 3856. 3857. 3858. R T H U_ R H. T H O M A S§ Cc O M P A N Y é'. I 3852 é fe Ascarite Midvale Absorption Bulb, designed by Mr. H. L. Frevert, formerly of the Midvale Steel Company. This bulb is very similar to No. 3851, except that it is only 25 mm diameter and is 120 mm high, not including the rubber stopper and inlet tube. Without rubber stopper or capillary inlet tube.. 1.45 Directions: A small amount of absorbent cotton is placed at the bottom of the tube under the capillary tube. This is covered with calcium chloride 20 mesh to a depth of } inch. A thin layer of cotton separates this from the soda lime which is next added until the bulb is nearly full. The top of the soda lime is covered with a small amount of cotton. The tube is closed with a rubber stopper carrying a short length of capillary tubing bent at right angles. The tubes are always weighed filled with oxygen, change of weight by diffusion having been found to be negligible where the tubes are in constant use. New tubes, or with tubes which have been allowed to stand more than 30 minutes, oxygen is used to displace air before weighing. The outlet of the tube is connected with a small bottle containing clear barium hydroxide solution. This serves as a bubble counter to give an indication of the progress of the combustion and to detect complete saturation of the soda lime in the tube. Ascarite, the special Stetser-Norton Sodium Hydrate Asbestos Absorbent can be used in this tube in place of the soda lime. Midvale Absorption Bulb, Stetser and Norton Modification. This is a modification of the original Midvale Absorption Bulb designed by Mr. H. L. Frevert, formerly of the Midvale Steel Co., the changes being suggested by Messrs. Stetser and Norton. It is simple in construction and when filled weighs approximately 100 grams. It can be used for about 400 determinations with a one-half carbon factor weight, carbon .50°%. The bulb measures 45 mm diameter at the widest portion, and 120 mm over all. It is provided at the top with a capillary tube and rubber stopper. . 1.50 Directions: To fill, put in a layer, about } inch, of glass wool to prevent stoppage of outlet tube, then add Ascarite until bulb is almost full. It is suggested that the absorbent be tamped down lightly with a straight piece of wire. j According to the designers, the bulb is used with the outlet end of the Vanier Combustion Train, i. e., with the Vanier Zine Tube and Vanier Sulphuric Acid Bulb;—a dryer, therefore, is not necessary. One bulb should absorb about 10 grams of CO,z. The outlet end of the combustion tube should be filled for about 3 inches with asbestos previously ignited, other- wise the sample will run high. The first three or four samples are apt to run low. With the author’s method, results can be made in from three to four minutes, 20 seconds being required for the start or burning of the steel drillings, one minute for actual burning, and two minutes for washing the gas out of the train. It is recommended that from 1 to 1} liters of oxygen be used with each sample. Reprint by Messrs. Stetser and Norton on “Rapid Combustion,” in The Iron Age, August 22, 1918, describing the combustion train, method of operation, etc., in detail, will be sent upon request. Midvale Absorption Bulb, Stetser and Norton Modification, with glass stopper. The advantage cfthe glass stopper is that it eliminates danger of loss of weight from the rubber stopper.......... 3.00 Midvale Absorption Bulb, Johnson Modification, similar to No. 3851, with rubber stopper and capillary tube, but with moulded base as suggested by Mr. Chas. M. Johnson...................... 2.50 Johnson Absorption Bulb, for the absorption and weighing of CO, in the determination of carbon in iron and steel by the direct combustion method. Designed by Mr. Chas. M. Johnson, Chief Chemist, Park Steel Works, Crucible Steel Company of America. This bulb may be used forty times with one filling of potassium hydroxide solution. Complete with drying tube, rubber stopper and PUD DOR CONMCCEL OME scctnn, cence eed as Saree: SGM NeS Hh BIB EA hua hay veo Detain ie acy Hl oss Ck wh RPA oes 2.50 Drying Tube, only, for Johnson Absorption Bulb.............0.0..00 0000 cen -75 Johnson Absorption Bulb, only, without drying tube, rubber stopper or rubber connection......... 1.75 Directions: Fill the cylindrical portion of the bulb with liquid caustic potash solution (1 gram of caustic potash to 1 ml of water) to a depth of 2} inches. The small bulb of the drying tube on the side is filled with glass wool or ignited asbestos. Next to this is placed a loose layer of soda lime 2} inches deep crushed to the size of a grain of wheat. Following this is a 14-inch layer of dry caustic potash in granules of about the same size. Below this is placed a small wad of asbestos. The tube is then closed with a rubber stopper. ASCARITE. Our trade-marked and proprietary sodium hydrate asbestos absorbent mixture, according to the formula of Mr. J. B. Stetser. For use especially in the Midvale Bulb, Stetser and Norton modification; can also be used equally well in the Fleming and Nesbitt Bulbs. One pound is suf- ficient for approximately 2000 determinations. In use in the most prominent steel works labora- tories:inthescountry.” Perl bint cicecee 5 gate eee sctineca ae ae tom egisds nates ad aces emer 4.50 3860. 3861. 3864. 3865. 3866. 3868. 3869. 3870. 3872. Combustion Boats, S. C. P. Porcelain, glazed throughout. Length,mm......... bey ah ogo a See areca ni on Leet sara 60 75 100 145 Width; MMe rs ysiena etew aha Ratan eos be oe ery eae 10 15 18 14 Bache cies esti heer ne cA eee ca ee Maceo “hae eo .30 57 .70 10% discount in carton containing..... die Path can phates Mis 300) 50 50 50 20% discount in case containing.............-.....-.00005 300 300 300 300 Combustion Boats, Coors Porcelain, glazed throughout with exception of outside bottom surface. Lengthiimm: 2.02 eee ats noel sao ge k 60 60 88 97 100 Width,mm...... elu este p ott enmth hes isan ii 10 12 16 20 Height, mm...... Eats ape eae ers eatery ane: 8 8 8 10 13 EACH guccgayeleseutite-oautineos ns ag, wee BO a Peas. a Ree aL See .26 .26 .30 32 34 Combustion Boats, Opaque Silica, glazed, without handle. Thengthinches'. <0: sore ee gee eae tae meee nts 12 3 3 4 6 Width, inches); guvncpaeda reas eee eee o8 4 > = 3 3 SACHS cores ences Amn otha nea Celene ears 65 1.00 1.15 1.50 2.00 Combustion Boats, Transparent Silica, without handle. Length, inches: cs dnc pe.nedin aes Pe nse 13 3 3 4 6 Width; Inches#s sce2cesc cee ees Pure 4 2 7 3 5 ACI Ae eA cnt ne ce ee re a node are er 1.90 3.45 3.75 4.70 6.90 Combustion Boats, Alundum, Mixture RA84, adaptable to a great variety of work, but particularly designed for the determination of carbon in iron and steel. The boats may be used repeatedly, because the alundum does not react with the iron oxide in the sample. Shapes have been carefully designed by practical chemists. Bengthwinches cs ok i each wom ei haiaiaveh yeas 4 3 475 5 5} Width: inches: \.n..ien.23. sek iee ei eee oe AE: oe 4 2 ie 4 2 Depth; MmCheseas.¢ ais4 ti cds) inn oe hae edhe a 2 ts ie Te AC HU oct cene oah sshs Pea ate ie ese Sotdewsags) aml enero .30 35 4 .40 -40 Combustion Boat, Johnson, vitrified clay, with pourout; 62 inches long by 142 inches wide by }i-inch TI Ste seein cee aber cornet Selo aa aria ie enrneae Saannge Then Sakis Ret Ohee Auer sR ngsin tener eens 1.50 Combustion Boats, Johnson, vitrified clay. Length; inches, .9;4-cccunuka sted eoeek 4 4 4 43 54 5} Width, inches............ Soy eR ae a5 3 3 a 3 u Depth, inches... 0 .4.464¢ a0de seen eas 76 3 ts 2 iG Ts Weal in Chess yoy crtacateyvet eed gisans Lent, nar Te is ds ts ve Ba CH ee aie Ch yest gonads Sus wins a op eo 18 7 20 19 24 .23 Combustion Boats, Pure Nickel. Voenigthisin ches), 2uicssa oer ea es aS Dae a De es 3q5 5 Width re ee LES AS OS, SNe SIM Tit a Aa et Witcriess nae Nc a ees Rew to A Te * 3 BG ieee eee eae ey as SESE AES FES He LE OSS PR Ly ACRE Ep Meg nak VERA -40 1.20 Combustion Boat Shields, of Alundum, Mixture RA84, for the protection of combustion tubes from the spattering of overheated metals during combustion. Tength, inches: 2.056 si08 ce noe Reds cals nen Pee ere Sea ae ee ea 43 55 Inside diameter, inches............ at Res Mea cAwe aie ra Sica treet aa anaes R te Outside diameter, inches................ ere Spee ETN Sonus eiiatay mea Aes 4 g MAC Hise tetera eM ete ea Rg Me ice arn an CR AN glee ee Rare SON eer 3.00 3.00 Combustion Boat Linings of RR Alundum, particularly recommended for use in Alundum combustion boats in protecting them from molten metal, thus increasing their durability and preventing their destruction during combustion. The lining is spread on the bottom of the boat before introducing the sample. The sample may also be covered with a thin layer of the lining, which protects the tubes from the spattering of the burning metal. Consists of pure fused aluminum in granular form, supplied in glass-stoppered bottles. RR Alundum, ye Label, as above described, regular material, free from carbonaceous matter only. Sizeremeshiyys eis otter cen seme ge Pe seed fered cyt sees anata Rer tbs Dottle scars: se so alas oc ee Bes bmi cee 1.16 1.16 1.16 Per 2 lb. bottle Reverie niece Reape ye eee rem pe Tt mes Peagecriin. MGS, 1.65 1.65 Per 5 lb. bottle. ............. SMe a tarr Ah salle eon n Revita ae ada Ae ne Sits on 3.30 3.30 3.30 Per (5 UD Canine ches Sry a 2s ccs ens eae ened Se Ne ch A riage 2.37 2.37 2.37 ry cL A ae ES nine te ee ee siuicn@) RR Alundum 3880 3885 RR Alundum, Blue Label, as described on preceding page, specially treated to remove carbonaceous mat- ter and surface alkali, giving a very satisfactory blank determination for carbon. DIZORIMeshieeeset since eae ear ean ae A Nr eee oak Cel rie ele 46 60 90 Per 1 Ib. bottle. ee ne tis ere mg eters er na . 1.43 1.43 1.43 Per 2:lbi. oe, ees Relea WA ern eet ay eae oe ee dk 2.15 2.15 2.15 Or ce) ses oie Case ee ected re ghee ine ore ea ne ee 4.07 4.07 4.07 3876. Combustion Capsules, Alundum, Mixture RA84, for ashing coal, coke or other inorganic material. Superior to impervious porcelain because of the higher thermal conductivity and because the porosity of the Alundum permits a more rapid oxidation of the sample. Size 13 x 2 inch igs standard A. 8S. T. M. size for coal analysis. DD AMetER) ANCHES* (2 24icaAe eiacee eee ieee ack ew eae ees 14 1 13 12 Height: nchesiniie st foc edi dee ep dthg Hie A voce nines Werle ea ic 3 2 % UCM ere Seah ec ed coe eine hes dy Rash gine Pes oh ts Ny eee ees Wy oe ee .30 -40 -50 -50 3877. Combustion Capsules, S. C. P. Porcelain, glazed throughout with the exception of the outside bottom surface. Without lip, as used in coal analysis. Size 40 x 22 mm is the standard A. S. T. M. size for coal analysis. IB TAWA COR Cinna ete) Oh geese a. Mae ra ware th Mai ate ee a re weal art ee 40 45 50 DDO Pty sia, discs ceases sas ces 2 ev erat Ade ie a eh eodete onucess are apa Mcveries dans wea 22 22 30 Ba CT eee eee aye tela aha ak I acreage eras Een Gh trac Neealny Duce wtp fy BE iD, 26 .30 10% discount in carton containing 24. 20% discount in case containing 288. 3878. Combustion Capsule, Coors Porcelain, without spout, with rounded bottom, glazed throughout with exception of outside bottom surface. Diameterat.top mm. 22 2155 cet ale aeesetcen es tluee saad eee oleh So ds ae hc tek AUB Bs 42 50 JACI NE AMM ses on. cos kp cee ein vse eo dene oN RO Se eR Dt ee eee a 25 30 Capacity; dmlvis, < sa yes as Gin hel ee, Cala 3 GM fs sal anaemia, Udon Mens topa inden fa at 25 50 BOF: Vel | ae peste enn fe te ea en PR ERI Se We Ae ae Rie ae ere a ne PUTED VE PULSER Sh .30 36 3880. Combustion Periscope, Smith-Rudy, for placing in the end of the combustion tube when same is in place in a tube furnace for the observation of sample during combustion and ignition. Designed by Smith, Rudy & Company, of Philadelphia, and used in their laboratory. The device consists of a brass tube, with a gas-tight glass window, side tube for gas exit, and angle mirror on which the image of the interior of the combustion tube can be plainly seen by the operator. The use of this device avoids the necessity of bending down to look directly into the end of the combustion tube for observation of the steel sample during ignition....................0.0.......0.. 6.00 3882. Combustion Tubes, Porcelain, suitable for high temperature work. Glazed on the outside only. Tength in Chess: sci, vg ta nae ee eae ie sa nade Ag seth Rd ot UD ae tad hie 24 30 Imside: diameter inches). s)oce25.5 cite schon wats @ Qiateauk wd phen eis Ra Alea ne z _t BACH ke eee ea eee th areata oo ace ose oe ENR RES EM cee OE aE RAL 6.50 8.00 3884. Combustion Tubes, Opaque Silica, Glazed, with one end reduced for rubber tubing connection. Con- stricted end is }-inch bore by ;;-inch outside diameter by 1-inch long. shotalslen ath scan ChHescrs seus epinedeiny sara ccicaue oeus cst getracitsema seers ge emer ae eee a 25 31 Inside diameter of tube; inches): 2. jyiceebss diet basdivieves caw bis awabohess qt 3 CW 2h eC ea OT eae SRT OU IS ooo Sins MIDIS RON A CURA Gites ramps ene eo e 8.75 10.50 3885. Combustion Tubes, Opaque Silica, glazed inside and unglazed outside; for temperatures up to 1100° C. A tube 24 inches by j inch can be used with Hoskins Combustion Furnace if the ends are water- cooled to prevent deterioration of the stoppers. Water-cooling is not necessary if a tube 30 inches long is used. Length, inches................. 24 24 24 30 30 30 Inside diameter, inches.......... 3 2 1 a 7 1 Ba chien econ ee eo a ae 5.60 6.10 6.70 7.00 7.62 ~ 8.38 3886. Combustion Tubes, Opaque Silica, glazed inside and outside; for temperatures up to 1100° C. Length, inches................. 24 24 24 30 30 30 Inside diameter, inches....... st a 4 1 3 z 1 a chistes ne ce een ee 6.90 7.40 8.70 8.63 9.25 10.88 Notr—Silica Tubing of other diameters is to be had on special order, but it is not carried in stock. 175 de se LR H. T H O M A _S CO M PP A N ¥Y 3888. 3889. 3890. 3891. 3892. 3893. 3894. 3895. 3896. 3897. 3898. 9324. 8450. 2032. 6005. 5977. 4260. SSS oe a A Ge eS Combustion Tubes, Tapered, Johnson, of vitrified clay, of new and improved composition. When used with tapered clay connector, rubber stoppers are unnecessary in carbon combustion work, etc. See Journal of Industrial and Engineering Chemistry, July, 1913. The 23}-inch tube, without rubber sleeve or clay connector, is the one in universal use. Tenable an Chesievc 20. ecteieee ae tas ete ot weed le Getic ia th ania lee en ae ad Sha wae saree ewes 234 274 273 Insidé-diameters inchesis 2.3 Sh na Ase eve oes ah eeu Sa hoes OA aa : 3 i4 2B Each, without rubber sleeve or clay connector.....................000-200-55 5.75 6.25 6.50 Tapered Clay Connectors, only, for No. 3888 Tubes, without rubber sleeves. For tube of inside diameter, inches...... Sy a ree ean en eee eee 3 44 Ta ACHE eee tae Ace tee a RON Eee, PRP EAL ADRS EN cattle ica eid ohh me Ma a oarats 200) 2:25 2:25 Rubber Sleeves, only, for No. 3888 Tubes. Each...........................000.. 1.75 2.00 2.00 Zine Jar, for use with 30-mesh zinc, part Z of Fleming Combustion Train....................... 1.00 Phosphoric Anhydride Jar, part O of Fleming Combustion Train.............................. 2.50 Mercury Pressure Gauge, part K of Fleming Combustion Train..................0............ 1.60 Stopcock, part C of Fleming Combustion Train............0....00.000.0 00000 ee 2.50 Mercury Valve, part V of Vanier Combustion Train and part M of Fleming Combustion Train.... .90 Zinc Tube, Vanier, part E of Vanier Combustion Train..............00.0. 00.0 0.0 .80 Drying Tube, Vanier, for sulphuric acid, part F of Vanier Combustion Train.................... 1.40 Mercury Gauge and Safety Tube, part A of Vanier Combustion Train............ Ga deyth eel aoe 1.50 Meyer Sulphur Bulb, for the determination of carbon in iron and steel by the use of barium hydrate. Waithout-stopcock=: (Wath 0 bulbsa eck a 8 og ea aioe el each nap lth ey ln Anitesh 3.35 INOFris? POtaS IY Bue srage ios od aeestner usec ates Gan) eevee ca ae el ines ed cae to oe en ei eee ee .85 Factor Weights, for use with Combustion Trains in weighing charge of boat, also used in steel works laboratories for analyzing silicons and phosphorus. Of lacquered brass, except the 1/10 silicon, which is of platinum. Style sts oes ie ee ... Carbon 34 Carbon + Silicon Phosphorus 1/10 Silicon Weight, grams..... 2.7273 1.3636 1.1755 1.63 0.4702 POS cea awe 1.75 1.75 1.75 1.50 8.00 Gas Holder, made of leaded iron, painted and mounted on an iron frame, with sliding receiver, pulley and weights, for regulating the oxygen pressure. Capacity, 20 gallons.............. .... 70.00 Gas Pressure Regulator and Reducing Valve, Hoke-Phoenix, for use on high-pressure cylinders of oxygen for reducing the high pressure to the low pressures required in combustion work. The large dial indicates how much gas is in the tank and reads in pounds per square inch from 0 to 3000 lbs. The small gauge shows the. delivery pressure, which is controlled by the regulator, from 1 to 40 Ibs. as desired. With directions for operation.........0.0....0 000.0 e eee. 33.00 Johnson Laboratory Milling Machine, for taking samples of thin sheets, wire, resistance ribbon, nails, steel blades and small samples of all kinds that are irregular in shape for use in carbon determi- mations-invinon ands steel Analysisy: css cnscencyssa earns ithe aes ok eas ues ee dae tay omen made 60.00 3900. 3901. 3902. 3903. 3904. 3905. 3906. 3908. 3910. 3912. 3913. 3915. i | Ae eat = AYN n \ J DWI ON AMA , INN AG 5 \ Soo 3900 3901 3902 3905 3908 3910 3912 3913 3903 3904 3906 Condensers, Liebig, of glass, with condensing tube in form of coil sealed in water jacket. Packed in individual cartons. Length, shoulder to shoulder, mm.................... 200 300 400 600 Each. SR ony hin oat Na Mae ean atte me con tI yan Rene ATE re 2.10 3.10 4.20 6.50 10% discount in case containing 12. Condensers, Liebig, of glass, with rubber connections. Packed in individual cartons. Length, shoulder to shoulder, mm... 250 300 400 500 600 800 1000 ache ste cts paneer tee ee ea 1.20 1.40 1.60 1.80 2.25 3.25 4.00 10°% discount in case containing 12. Condenser Tubes, only, for No. 3901 Condensers. Total length,mm................. 540 590 700 800 900 1100 1425 Outside diameter, lower end, mm... 11 fT 11 11 12 12 14 For condenser, mm long........... 250 300 400 500 600 800 1000 Baehine air ceed acer penne 25 -40 -45 55 -65 .70 -80 10% discount in case containing 12. Condensers, Liebig, of Pyrex glass, with loose inner tube, but without rubber connections. Approximate length of jacket, inches........................ 10 12 20 24 Bac hieess oes pews ee hate ae aed tm ic et re eae OR MAY hh arta 2.40 2.60 3.60 4.00 Condenser Tubes, oniy, of Pyrex glass, with enlarged top. Approximate length InChes 2.) 6 ese Go. ka Awd BS sgs w Soha nao peabenat 18 20 28 32 SACI es ee RA Lea a Ey st est MAY nein SEMAN betas AA: aint ati: Ber eet -50 .60 .80 1.00 Condensers, Liebig, of glass, with inner tube sealed to body. Packed in individual cartons. Length, shoulder to shoulder, mm.................. 250 300 400 500 600 ACT Fy he scotch ns oe a AN lepton a WB Riee POL IEA Ht 1.50 2.00 2.25 2.50 3.75 10% discount in case containing 12. ditto, but of Pyrex glass. Total lengths tin Chess. i705 ce evs cies ist aoe Sets Sas ten teen mieten eat oe 10 12 20 24 ACH ie oretined ih gee ey peng on Mia Siena. eae as 2.80 3.20 4.40 4.80 Condensers, Allihn, of glass, with bulb condensing tube. Packed in individual cartons. Length, shoulder to shoulder, mm.......................... 200 300 400 600 ACI Oe Ge One Mee SON ae a Sra eg SN a en er ame eine eh cca 2.00 2.75 3.00 4.50 10% discount in case containing 12. Condenser, of glass, with bulb condensing tube, as used in No. 4986 Soxhlet Extraction Apparatus. Length of condenser, mm............00.0 0.0 c eects 200 250 250 To fit Extraction Apparatus,mm.............0 0.00.00 c eee eee eee 30 38 50 ACH oes oy ee ik NES ae See Rael Po amc neem mere las eaprera ne sens mt wales 2.00 2.00 2.50 10% discount in cartons containing 12. Condenser, Hopkins, outside jacket shoulder to shoulder 350 mm long. As widely used in Extraction Apparatus. See Journal of American Chemical Society, December, 1908. Packed in individual CAREOIIS eooetc sextet sah ae ernie Sone nitin Arg econns sites su aha hae ore Ruch cists Pitanisbahes ert atinvin oosditan ised ncaa Eo ieratl eaten) sheeted 3.50 10% discount in case containing 12. Condenser, Hopkins, Picard-Law Modification, with the side tube bent upright at right angles, with a funnel top so that the fluid may be poured into the condenser without disconnecting the tube when used in connection with extraction apparatus. Widely used in cotton-seed oil work.... 4.00 Condenser, Sulphurous Acid, Liebig, of glass; with two stopcocks on horizontal tubes............ 3.00 177 3916. 3918. 3931. 3932. 3933. 3934. 3940. 3941. 3931 3920 3930 3940 Condenser, Friedrichs, with ten turns of spiral. Dimensions 200 mm long by 40 mm diameter... 6.50 Condensers, Gockel; may be connected airtight with receiver and used either as a reflux condenser or for the determination of inflammable substances where dangerous gases must be led off from inside. Packed in individual cartons. Length of jacket, shoulder to shoulder, inches............................0... 18 24 RC Hitate oe Seer step Das nett = ee Ponte Sine conte oer AN edhe ea eere Mi RL ae e hai Ot E a TIEY 4.00 5.50 Condenser Tube, for use in the official Brown-Duvel Moisture Tester. Made in accordance with specifications of the U. S. Bureau of Plant Industry, Circular No. 72.......0..0..0 2.000005 Condensers, of brass, with condensing tube of glass and with rubber stoppers. Werte, Amn 5 cs ic deka a coco 4S hua esas eae 300 500 600 750 1000 BCs oes cds ac on cede ao ence Gea ed Lee eS 3.60 4.75 5.25 6.50 7.40 Condenser, Hallock, of copper, with pure block tin condensing worm, 143 inches high by 4 inches diameter. With outlet and inlet tubulations, and two rods for clamping to apparatus support. As used in the determination of ammonia nitrogen in water by the distillation method, etc............ 8.80 Condensers, of zinc, with heavy block tin worm. For use with distilling apparatus such as No. 4700. For still of capacity, gallons RES AEP ea teae es 7 Racca mgt eas ooge Pate eine aro a Naat nee cae: her el a 6.40 8.00 9.60 12.80 16.00 Condenser, Soxhlet, spherical, of copper tinned inside, 4 inches in diameter....................- ditto, but with two bulbs Condenser Support, consisting of Support, extra large, Clamp Holder, 3-inch size, and Clamp, 11-inch. Complete 27 Condenser Support, for condensers up to 60 mm diameter; with double clamp of brass, on iron one The clamps are 12 inches apart, therefore cannot be used with small condensers 178 A R T H U_R Fg T H OF M AS Cc O M P A N_ Y CONDUCTIVITY OF ELECTROLYTES Apparatus for its measurement, particularly selected to meet the requirements of chemical and biological laboratories Since the publication of Kohlrausch and Holborn’s “‘Leitvermoegen der Elektrolyte” there have been marked advances in the practical application of the theory of electrolytic conductivity measurements, such as the devel- opment of better sources of e.m.f., the use of air condensers for balancing out the capacity of the electrolytic cell and connections; new methods of winding resistance coils; improvements in detecting and indicating instruments, in methods of laying up, sheathing and connecting all cables; and the employment of inductive shields. We offer in the following pages a selection of equipment for use in the precise determination of absolute conductivity values, and also for the utilization of such measured values or the indications found therein, in the laboratory control of industrial processes, for the location of end points in reactions where abrupt changes in conductivity take place at the end point, and for a great variety of other work wher: absolute accuracy is less important than relative accuracy. _ Apparatus for educational work is also included, embodying such features as clearly illustrate the methods used in electrolytic conductivity measurements of high precision. The accuracy attainable with some of this less expensive apparatus is such as to invite a considerable use in routine a alytical work. SOURCES OF E.M.F. The induction coil used in the outfits of he pioneer workers in this field has been mostly discarded in favor of more satisfactory sources of e.m.f., such as the Vreeland Oscillator, the Constant Speed 1000-Cycle Motor Generator, the Microphone Hummer, and the ordinary commercial alternating current circuit of 60 cycles. For the most precise determinations of absolute conductivity values, the Vreeland Oscillator is recommended because it delivers a high frequency current, usually 1000 cycles, of symmetrical wave form, without harmonics, and the frequency is not materially affected by changes in load conditions. The Constant Speed 1000-Cycle Motor Generator also yields a current of symmetrical wave form, free from the distortions which characterize the current from induction coils, and while the wave form is not purely sinusoidal like that from the Vreeland Oscillator, it is suitable for many kinds of measurements. It is particularly recommended for use in educational laboratories of physical chemistry as its output is sufficient to operate simultaneously any number of desks up to twenty. The Microphone Hummer now supplied with tuning fork control also yields a frequency of 1000 cycles with a wave form permitting a good minimum to be obtained so that the balance point is easily found. Its power output is sufficient for all purposes, and it is recommended for general laboratory use in conductivity measure- ments. Perhaps more important for routine analysis is the utilization of commercial 60-cycle alternating current by means of an indicating instrument such as the Portable Alternating Current Galvanometer instead of a tele- phone receiver. The surrounding noises in no way interfere with the securing of a satisfactory balance, and in addition the Galvanometer indicates in which direction the bridge is unbalanced. With this Galvanometer is usually supplied a Unit Type Dial Wheatstone Bridge. Where alternating current of 60 cycles is desired, and only d.c. is available, a rotary converter should be utilized from the a.c. side of which 75 volts is obtainable. This can then be stepped up to 110 volts by the use of a small 50-watt transformer. Price of both of these units is submitted on application. CCT TT CCTCCCCCCCTRT TCC NNN BC SUECCCTCCLLCCCCCTCCU XCAR ' i I AA 3946 3946 Vreeland Oscillator, Complete Vreeland Oscillator, Without jar Vreeland Oscillator, L. & N., Simplified Form, producing a pure sine wave alternating current at either 500 or 1000 cycles per second. Either frequency is maintained constant without the use of auxiliary apparatus. With cooling coil for use during long operation. The energy is derived from an ordinary direct current supply circuit and the transformation to sinusoidal alternating current is accomplished by purely electrical means, not involving the use of moving mechanical parts. The oscillations are generated in a tunable oscillating circuit (which is a fixed part of the instrument) containing capacity and inductance, and the frequency is determined by the elec- trical constants of this circuit. By varying the capacity or inductance the frequency may be varied at will, but, once adjusted, it remains practically constant, excepting in so far as very small changes may be produced by overloading of the secondary circuit. The purity of the wave form is such that the most rigid tests have failed to disclose any harmonics whatever and, within the limits of output of the apparatus, the frequency is not ma- terially affected by changes in load conditions. 3946. Vreeland Oscillator, L. & N., Simplified, as above described, for use on 110 volts d.c............. 325.00 179 3947 3948 3947. Constant Speed 1000-Cycle Motor Generator, L. & N., consisting of a laminated toothed wheel driven by an electric motor automatically governed to maintain a constant speed to within }% and with a maximum power output at 1000 cycles of 2.2 watts. This Motor Generator yields a current of symmetrical wave form free from the distortions which characterize the current from induction coils. Although the wave shape is not purely sinusoidal like that from the Vreeland Oscillator, it is suitable for many kinds of measurements and is especially recommended as a source of high frequency in educational laboratories. Its output is sufficient to operate simultaneously any number of desks up to twenty. The Generator should be placed in a sound-proof enclosure, preferably at some distance from the testing bridge in order to avoid confusion in balancing same. With universal motor operating on 110 volts a.c., 60 cycles, or 110 volts d.c.........------- 00 200.00 3948. Microphone Hummer, or “Howler” Set (Audio Oscillator), providing an alternating current with a frequency of 10 0 cycles controlled by a tuning fork attachment, which improvement makes a satisfactory equipment for a great variety of conductivity measurements. Its wave form is such as to permit a sharp minimum to be obtained so that the balance point is easily found, and it is also much superior to the induction coil for electrolytic measurements. Its power output is sufficient for all purposes. Its low cost makes possible its use in educational laboratories where it is advisable to provide students with individual sets. Operates on 6-volt primary or storage battery. The outfit should be placed in a sound-proof enclosure, such as a box with heavy felt packing, to avoid confusion in balancing the bridge.............. 32.00 > ree aE DETECTING AND INDICATING INSTRUMENTS. A telephone receiver properly tuned to the frequency of the exciting source is undoubtedly the best detecting instrument. It is obvious that the fundamental period of the telephone should coincide with that of the alternating current source of power and that it should have a natural period the same as that of the average human ear, which is in the region of 1000 to 1500 cycles per second. The telephone must be designed to avoid the accentuation of the upper partial tones, particularly the third, which is the one most in evidence in an alternating current source of e.m.f. Its use for precise measure- ment demands an absolutely quiet room and, while more or less nervous strain is involved in pushing the tele- phone to its limit of audibility, it is by far the best detector employed at the present time. Ear mufflers should be employed in connection with it as they are of great assistance when attempting to balance closely. The single telephone receiver with headband will be found satisfactory in educational and other work not requiring the greatest accuracy, particularly in connection with the Microphone Hummer. The Leeds & Northrup Portable Alternating Current Galvanometer meets the requirements for an indicating instrument where the ordinary alternating current commercial circuit of 60 cycles is used as a source of power. In this instrument the alternating current through the coils of the field magnet produces an alternating field in the region in which the coil is free to move. The alternating e.m.f. influencing the moving coil by an unbalanced condition of the bridge must at all times be in synchronism with the alternating magnetic field. A steady deflection thus becomes possible, which approaches zero as the balance in the bridge is approached. Three binding posts on one side of the case make it possible to obtain any one of the three values of low voltage alternating current for the bridge circuit. The two binding posts on the other side of the case are the terminals of the galvanometer moving system. 3950. Tunable Double Telephone Receiver, for use with the Vreeland Oscillator, the Constant Speed 1000- Cycle Motor Generator, or the Microphone Hummer. The ordinary diaphragm is replaced by an iron reed tuned to a suitable note, to which a suitable aluminum diaphragm is screwed. A knurled head adjusting screw at the back of the receiver case provides for setting the reed to the position for maximum sensitiveness. Mounted on light aluminum head-band with a double swivel motion to fit the ears, and sliding adjustment for the size of head. The weight of the complete head-gear, without cords, is 10 ounces. Specially constructed for conductivity work; 110 ohms TESIStANCE LOT CAC HERECEIV Clears a ues. vivee, Arise Braye inate Gym eon hells hold ions Bene. te ne Ol ne Posen 8G 20.00 3951. Double Telephone Receiver, with head-band, for use with Microphone Hummer 180 3952. Alternating Current Galvanometer, L. & N., Portable, for use on 110-volt, 60-cycle, alternating current, lighting or power circuit. With interchangeable moving system with voltage values of 3, 6 or 9 for operating low resistance bridges. With lamp cord and plug........................... 60.00 3953. ditto, but with moving system with voltage values of 6, 9, or 15 volts for operating high resistance DIVA OS son eset toa ates arsacaten etior a cpet ls exer extn ttt airoeetre pote emteneat Sap aes cet 15 a eke ean ey Renee 60.00 3954. Moving System, only, for No. 3952 Galvanometer, with voltage values of 3, 6 or 9 for operating low resistance bridges; interchangeable with moving system of No. 3953 Galvanometer........ 20.00 3955. Moving System, only, for No. 3953 Galvanometer, with voltage values of 6, 9 or 15 volts for operating high resistance bridges; interchangeable with moving system of No. 3952 Galvanometer... 20.00 ee Lr 3959 3960 MEASURING BRIDGES. The Leeds & Northrup Kohlrausch Slide Wire Bridge is recommended as a most satisfactory bridge for measurements of both the utmost precision and for those of ordinary accuracy. The simplified form of this bridge meets many requirements as to range and accuracy, and is recommended as superior to the ordinary Meter or Half-Meter Bridges. Where the A.C. Galvanometer is used in connection with 60-cycle a.c. circuit, we recommend the Unit Type Dial Wheatstone Bridge. The Half-Meter Bridge is still preferred for student’s use by some instructors to the enclosed type Slide Wire Bridge of the Kohlrausch form. 3958. Kohlrausch Slide Wire Bridge, L. & N. A circular slide wire bridge with extension coils in its base of such value that the slide wire resistance is but 1/10 the total. It is provided with ten turns of wire on the drum with a resistance of about 27 ohms and each of the extensions has a value of about 122 ohms, making the total 271 ohms. The extension coils are wound for annulment of inductance and capacity at a frequency of 1000 cycles per second. The above choice for resistance of slide wire and extension coils has been found in practice to be a desirable one for general use. The bridge has a scale of 2000 parts, each about 34-inch long, readily subdivided to 1 part in 10,000 of slide wire, or 1 part in 100,000 of ratio arm. The slide wire is sufficiently large to withstand considerable wear and abuse. The position of the contact is read by means of the vertical glass scale which reads complete turns and also by the scale on the periphery of the hood. The latter scale is divided in 100 parts, each division being about 6mm.......................0.. 125.00 3959. Kohlrausch Slide Wire Bridge, L. & N. Simplified Form. All metal parts are enclosed and the binding posts are rubber covered. The slide wire in this bridge has a resistance of 20 ohms, with a scale reading from 0 to 1000. Extension coils are provided, each of which has a resistance of 90 ohms, making a total resistance of 200 ohms. For use with the slide wire we recommend No. 3967 Dial Decade Resistance Box (0-9999 ohms). This permits measurements of resistance up to 10,400 ohms, the slide wire taking care of about 4% either way from a balance at its middle point.. 70.00 3960. Unit Type Dial Wheatstone Bridge, L. & N., for use where the Portable Alternating Current Galva- nometer is used as an indicating instrument in connection with the ordinary commercial 60-cycle alternating current circuits; with ratio multipliers, .001, .01, .1, 1, 10, 100 and 1000. One of the five dials controls the ratio arms, permitting the use of any decimal value of the ratio from .001 to 1000 inclusive. The other four dials control the rheostat arm of the bridge, with a range of 9,999 ohms in steps of 1 ohm. Accuracy of adjustment: ratio coils, 5° ¢; rheostat ;';%... 70.00 181 3961 3961. Half-Meter Bridge, with extension coils .............0. 00. eee eee : . 30.00 3966 3967 RESISTANCE BOXES. It is necessary in precise measurements of electrolytic conductivity to use resistances in which the effective resistance values at the frequency used will not differ from the steady current value by more than the percentage accuracy to which the coils are adjusted. 3966. Resistance Box, Curtis Coils, L. & N., with five dials, 10 (1+10+100+1000+10,000) ohms, for measure- ments in excess of resistance values of 1000 ohms. Curtis Coils must be wound entirely by hand in order to eliminate all inductance and capacity effects. Their adjustment and proper method of aging also require great care. The price, therefore, is very much higher than the plain bifilar wound collstot the: same -Valuesin 2.0.05. c. cote eke Ghicadiee nas pao ee We Casas Ben Y wh Sao eh ee 370.00 3967. Resistance Box, Dial Decade, L. & N., recommended for use with the Simplified Form Kohlrausch Slide Wire Bridge. With four dials and all contacts enclosed. Coils are wound on wooden spools, with accuracy of adjustment to 1/10%. Contains 9 (1+10+100+1000=9999) ohms.......... 55.00 3970 3971 CONDENSERS. In the most precise measurements condensers are used to annul the capacity of the elec- trolyte. They should have a power factor so small as to introduce no appreciable error. Energy lossin a condenser may arise from leakage, plate and lead resistance and absorption. Hence only air condensers should be employed, and they should be so constructed as to have low plate and lead losses and very high insulation resistance, and should be capable of continuous adjustment. The larger valued condensers should have a scale covering an arc of larger radius to facilitate accurate reading in those cases where the values are to be noted, as, for example, when measuring the dielectric constant of liquids. A condenser of similar type, but of very small capacity, is necessary for very fine adjustment and for balancing against low values. These requirements are met in the condensers listed below. 3970. Variable Air Condenser, with capacitance at the zero end of the scale of less than 30 micro-microfarads. The plates are heavier than those of the usual variable condenser of this size, and the end supports are arranged to reduce the usual dielectric losses. The rotary plates are mounted on a steel shaft which runs in two cone brass bearings, permitting of adjustment to any desired degree of turning resistance and of taking up wear. In spun metal case with panel of Bakelite, with engraving in vie figures and small extension handle for accurate adjustment. Maximum capacity 700 BVT haere eee eos cee ween ree ert tater same a are eat hn bath Mee decal Maen denen Ga ean 12.00 3971. Vernier Condenser, for use with Variable Air Condenser to secure very fine adjustment. The spacing of the terminals is so arranged that this condenser can be slipped directly across the binding posts of the Variable Condenser, thus permitting a parallel connection without using connecting wires. The stationary plate may be varied in distance from the moving plate, permitting a variation in maximum capacitance from .5 to 10 micro-microfarads. A hard rubber extension handle is supplied to avoid effects from placing the hand too near the condenser.................--- 8.00 182 AD Rf He Us IR H. T -O- MA. 2S GO. > UML aR A; Ne -¥ CONDUCTIVITY CELLS Washburn Conductivity Cells are recommended for measurement of electrolytic conductivity with the utmost accuracy. They were developed by Dr. E. W. Washburn at the University of Illinois, and described in the Journal of the American Chemical Society, 38 : 2431, 1916. The three types of Washburn Cell cover a range suitable for measurements from that of conductivity water and dilute organic solutions up to sulphuric acid of maximum conductivity. In the design of these cells filling tubes permit the filling of the cell with the minimum exposure of the electrolyte to the action of the air, and at the same time serve to support the cell in the constant temperature bath with the cell proper totally immersed therein. As electrolytes have high temperature coefficients of resistance, these cells are intended for use in a constant temperature bath when measurements of the utmost precision are to be made. For example, in conductivity water with a temperature coefficient exceeding -04 or 4 per cent. per degree C a change of 1/400° C in the temperature of the water results in a change in resistance of .01 or 1 per cent. _. Our Washburn Cells are made either of Pyrex, Jena or Nonsol glass because of the presence of soluble silicates in ordinary lime glass, which renders it unsuitable for this purpose, and the Platinum employed is a special grade free from iron and calcium. Diagram showing convenient arrangement for connecting up Washburn Conductivity Cells A simple and convenient arrangement for connecting up Washburn Conductivity Cells is shown in above diagram. The wires D come from the bridge and dip into the mercury cups A. The connectors C dip into the cups A and also into the mercury cups on the electrolytic cells. By always filling the mercury tubes of the cell to the same height with mercury and maintaining the same leads C, the lead resistances may be kept constant. For accurate resistance measurements, the value of the leads connecting the bridge to the cell must, of course, be known up to the electrodes within the cell. Where a number of cells are interchanged, it is desirable to have the lead correction the same for all cells. This must be done by supplying each cell with its pair of connectors C and marking on each cell the height to which the mercury should come in the tubes. It is convenient to remember that if care is taken to preserve the same lead resistance in both arms of the bridge it will never be necessary to make any correction for lead resistance, provided the distance of the bridge setting from the middle of the bridge fulfills the following condition :— s 5000 R p Rp + 200 R, Where R; is the resistance of each pair of leads, R is the box resistance, p is the allowable percentage of error from this source and 7 is the number of scale divisions between the bridge setting and the middle of the bridge. This assumes that a scale division represents 1/10,000 of the total bridge. n = Conductivity Cells Types LC, MC, and HC, are modifications of some of the earlier forms of cells for the measurement of low, medium and high electrolytic conductivities in a great variety of laboratory work other than that of the utmost precision as provided for in the Washburn Cells. They are especially designed for use without a constant temperature bath and each cell is, therefore, provided with a thermometer reading in 1/10° C, and with an interchangeable glass stopper for use when the thermometer is not required, i. e., when the cell is used in a constant temperature bath. As the cell constant is influenced by the presence of the thermometer in the electrolyte, it should be determined for each cell, both with and without thermometer, if the cell is to be used for both methods. One-tenth of a degree Centigrade corresponds to an average accuracy in measurement of about one-fourth of one per cent, in so far as this accuracy depends upon temperature. The glass tubes in which the wires holding the electrodes terminate are provided with traps to prevent the spilling of the mercury when the cell is inverted during the cleaning process. These cells have practically the same resistance range in reciprocal ohms as the corresponding cells of the Washburn type. For measurement of absolute conductivity values with the utmost accuracy by the fall of potential method, a special Conductivity Cell is recommended. In such work the Type K Potentiometer, as listed on page 244, is required, as is also a set of Standard Resistances NBS type of 10, 100, 1000 and 10,000 ohms; these being more suitable than the Curtis Coils, both because of their more accurate adjustment and the avoidance of a_high fre- quency source of e.m.f. These Standard Resistances and special conductivity cell are supplied on special order. For educational use, as well as for a great variety of conductivity measurements, the modification of the original Ostwald Cell mounted in a vacuum Jacket will be found satisfactory, as for much work it can be used without a constant temperature bath. 183 3974. 3975. 3976. 3978. 3979. 3980. 3981. 3982. 3983. 3984. 3985. 3978 3974 8975 3976 The following prices for Conductivity Cells do not include Platinum, for which extra charge is made at current rate Conductivity Cell, Washburn, Type A, for low conductivities, range in reciprocal ohms 10-* to 2 x 10-". ‘Approximate weight of Platinum 11 grams. Price, exclusive of Platinum................ 17.75 Conductivity Cell, Washburn, Type B, for medium conductivities, range in reciprocal ohms 3 x 10-? to 3 x 10-5. Price, exclusive of Platinum..... 15.50 Conductivity Cell, Washburn, Type C, for high conductivities, range in reciprocal ohms 1 to 10-*. Approxi- mate weight of Platinum 12 grams. Price, exclusive of Platinum 20.00 Approximate weight of Platinum 4.25 grams. =) { \ ff ‘if a do is a5 Re AQ WO fs] err zis} 2% le2| bl 135, Is vc te zal Ing EFI HF res 2NN ) 3980 3982 Conductivity Cell, Type LC, for low conductivities, with thermometer and glass stopper. Approximate weight of Platinum 2.95 grams. Price, exclusive of Platinum 20.00 Glass Cell, only, of above, with glass stopper and Platinum electrodes but without thermometer. Price, eExclusiverotsbla tintin | Aca Cv neineon cape rensaish ose a AMe yatta ROU Rr oid oe ae ee ee 15.00 Conductivity Cell, Type MC, for medium conductivities, with thermometer and glass stopper. Approxi- mate weight of Platinum 2.3 grams. Price, exclusive of Platinum....................... 18.00 Glass Cell, only, of above, with glass stopper and Platinum electrodes but without thermometer. Price, exclusive of Platinum................... 13.00 Conductivity Cell, Type HC, for high conductivities, with thermometer and glass stopper. : : : , Approximate weight of Platinum 2.35 grams. Price, exclusive of Platinum 2 Glass Cell, only, of above, with glass stopper and Platinum electrodes but without thermometer. Price, exclusivesol Platinum c nals pometeteuks au ay tah sedate doesn ede Ore nee eae 19.00 Conductivity Cell, Henry, similar in construction to Conductivity Cell No. 3978 but with 20 mm sepa- ration of electrodes. With thermometer No. 3986 and glass stopper. Approximate weight of Platinum 1.05 grams. Price, exclusive of Platinum 18.00 Conductivity Cell, Henry, similar to No. 3984 but with 2 mm separation of electrodes. With thermometer No. 3986 and glass stopper. Price, exclusive of Platinum 20.00 NotE—Conductivity Cells are supplied on special order with Gold instead of Platinum electrodes at correspondingly less cost. 184 A 3986. 3987. 3988. 3989. 3990. 3992. 3994. 3998. 3999. Ro Ho ur eR H. T H O M AS Gc 0 M P A -N Y eqianie—o in aT Y i a ; |4 a i i it I ‘oo LAM | | 3998 3990 Thermometer, engraved on stem, range 0° to 40° C,in1/5ths. Total length 185 mm, with tapered bulb 70 mm long; made and ground to standard taper for use interchangeably with any Type LC, MC, HC or Henry Conductivity Cell sold by us 5.00 Conductivity Cell, U-type, recommended for educational laboratory work; with adjustable electrodes held in place by means of a hard rubber top and clamping screw. Positions are read by means of the graduations on the arms of the tube. With filling tube and drain cock so that cell can be filled and drained without removing the electrode holders.. A thermometer can be conveniently inserted in the filling tube, but is not included with the cell. Complete with hard rubber top and clamping screws attached to mercury tubes which are provided with Platinum electrodes, approxi- mate weight of Platinum 1.40 grams. Price, exclusive of Platinum, for which extra charge is made AL CUTTOMLGT ALO toaicerva na terior a aes baie ata coe Pes NE se era do Lease dae rt aap ert inch pee ed aires Bigeye oes oot 17.00 Glass Cell, only, without mercury tubes, clamping attachment or Platinum electrodes........... 13.00 Mercury Tube, only, with Platinum disc electrodes, approximate weight of Platinum 1.40 grams. Price, exclusive of Platinum, for which extra charge is made at currentrate..................... 1.00 Conductivity Cell, Pipette form, consisting of a glass pipette of about 25 ml capacity, with glass stop- cock and with Platinum electrodes fused in the sides. The Platinum wire connection is made by means of a vulcanite ring firmly clamped on the outside of the pipette. This cell is adapted for the measurement of medium conductivities and is convenient to use in a beaker or other vessel containing the electrolyte to be measured in which a separate thermometer can be inserted for temperature control. Approximate weight of Platinum 1.25 grams. Price, exclusive of Platinum, for which extra charge is made at current rate..... 0.00.02. ee tees 20.00 Conductivity Cell, Dipping form, with three electrodes which may be separately connected in order to provide lesser and greater distance between them so that both high and low conductivities can be measured. This cell is designed for immersion or dipping into beaker or other vessel containing the electrolyte where it is inconvenient to remove same to a separate conductivity cell during the operation under control, as in following titrations or in the control of industrial processes. Approxi- mate weight of Platinum 1.55 grams. Price, exclusive of Platinum, for which extra charge is made PVG UCU ETA Gal UC ee steeds ash ce slesaus et Ba te g Cacia 8 Ba aslo Utehage accen iat eueuee oat ee Seatny 6 we Silt 20.00 Conductivity Cell, as specially designed for use as an accessory to the Kelley Electrometric Titration Apparatus when used in the measurement of the conductivity of electrolytes. Approximate weight of Platinum 0.95 grams. Price, exclusive of Platinum, for which extra charge is made at CAITR EN Gaal LO ocak ogee eyectssi oes Ge ete An a AS aa eps Dee CaS eae oS oISY Sean ASR se ol 13.00 Conductivity Cell, Ostwald, with vacuum jacket, consisting of cylindrical Dewar Flask, 100 mm long, with close fitting top through which are inserted the two electrodes of 15 mm diameter and 20 mm separation, the terminals of which are fused into glass tubes for mercury contact. An additional opening is provided for thermometer such as No. 3986, but this is not included in the price. The vacuum jacket protects the electrolyte from sudden temperature change and measurements can be readily obtained at the usual temperatures by introducing the electrolyte warmed to a temper- ature slightly in excess of that at which the determination is to be made. With goldelectrodes 6.50 ditto; but-with platinum electrodes. co1. se cektis Bie ieee aes goes en ee pee ee ads 10.00 5386. Flask, Dewar, Unsilvered, tube form, without base; 100 mm long x 45 mm outside diameter x 30 mm G1 OG CLATIO LOM ae redox, cvnencos etn beat to vse oa tees eee ev see a eae coe et arch eae were oe Meme cent at 3.00 AR TH UR H. T H O M A S C O M P A N YY CONSTANT TEMPERATURE BATHS. For precise work with high resistances an oil bath is required. A special kerosene may be used which, while free from moisture, is nearly devoid of odor. For most work, distilled water is satisfactory for a bath liquid. It is customary to make conductivity measurements at four tempera- tures, 2. e., 0° C, 25° C, 50° C and 100° C. The maintenance of 0° C requires an ample supply of cracked ice and distilled water, and 100° C a high boiling liquid at proper temperature. For intermediate temperatures a heating device is required and we recommend the incandescent lamp as its heating capacity is low and it does not have the same tendency to overheat or underheat as a resistance unit. Temperature regulation must be so close that the maximum variation in degrees shall not be greater than one-half of the allowable percentage error from this source. For very small constant temperature baths a Dewar flask is convenient. It is necessary to find the cell constant for each temperature at which it will be used, for this constant changes with the temperature, owing to linear expansion of the platinum wire, surface expansion of the electrodes, and cubical expansion of the containing glass vessel. As far as possible these sources of change should be balanced against one another by properly proportioning the elements of each cell. If the cell constant exhibits temperature hysteresis the cell should be kept constantly at the temperature at which it is used, or frequent determinations of the cell constant should be made. y Because of the difficulties of automatic and precise constant temperature control a simple type of bath without automatic regulation and intended for use with Beckmann Thermometers reading to .01° is recommended. Such a bath is No. 4010, which was developed by Leeds & Northrup Company for use with the Washburn Con- ductivity Cells. ; ; An automatically controlled bath regulating in practical work under fair conditions to within + 0.02° C over a period of five minutes, and to within + 0.05° C for periods of an hour or longer, is provided in the Freas Automatic Constant Temperature Bath, sometimes referred to as the ‘‘Small Sensitive Freas Thermostat.” There are no automatic constant temperature baths other than those described below that we can recom- mend for conductivity work, but we hope later on to announce the results of some experimental work now being done in this direction. 4010 4010 Exterior view. Without metallic jacket, with Washburn cell in position. 4010. Constant Temperature Bath, consisting of a glass jar 9 x 12 inches enclosed in a polished metallic jacket which provides an air insulating space. The removable lid is insulated with cork and carries the thermometer holder, adjustable support for the incandescent lamp and stirring device; holder A for two test tubes is also provided. These tubes are partially filled with mercury and in them are placed the amalgamated ends of the lead wires for connecting to the bridge through the binding posts B. Two insulated connectors run from these tubes to the mercury tubes of the conductivity cell. This method of making connections is convenient and reduces the passage of heat between the cell and the room, as both ends of the connecting wires are at the temperature of the bath. Support for the conductivity cell C is suspended across the top of the jar and the cell is held in place by spring clips. The stirring device is provided with pulley for belt drive, as this method keeps the motor away from the bath vapor and permits regulation of speed by means of cone pulleys. Price includes 110-volt incandescent lamp for heating, with cord and socket plug, but does not include Conductivity Cell, Beckmann Thermometer, Regulating Rheostat or motor for stirring device 100.00 4011. ditto, but with the addition of No. 9567 Beckmann Thermometer, Rheostat, 630 ohms, 1 ampere, for controlling the heating lamp and Cenco Friction Drive Electric Motor, 110 volts d.c., for oper- 1 ALIN G Che ScInRIM ed eVI CC rs a wcryala tes ehanwrrenanntiat c eian if oe uN Map anue ate gs be henge oy 69.50 4012. ditto, but with Cenco Friction Drive Electric Motor, 110 volts, 60 cycle, a. c., for operating the stirring IL OVACE aya Leesa navereresenie morse tony int ase, CRU RR a IR CML DSA mle oe on Kioh fan GPtiy aig 169.50 2097. Glass Jar, only, for above Constant Temperature Bath; 9 inches diameter by 12 inches IGA 8 ie went 4.00 186 A‘ Ri T H U_ R FY T H O M AS C.-3O> MUP A UNE CY. 5 iti G i i d aL i 4014 4014. Constant Temperature Bath, Freas Automatic, consisting of a glass tank 15 inches diameter by 15 inches deep, of about 10 gallons capacity. This tank is covered on the outside with horse-hair felt to a thickness of about one inch and on the outside of this felt is placed a cover of linoleum. A portion of this tank consisting of a strip about three inches wide extending from top to bottom is not covered with insulation and serves as a window through which the operator can observe his work. Reg- ulation is by means of the Freas mercury thermo-regulator, consisting of a Pyrex glass regulator tube filled with mercury working through a thermal relay. Heating is by means of two electric lamps. The stirring device is operated by an electric motor suspended by means of two springs as shown in illustration. This stirring device keeps the water in the tank in constant and thorough agitation. The regulator is sensitive to a range of .01° C, but in practical work under fair conditions a regulation within + 0.02° C over a period of five minutes and within + 0.05° C for periods of an hour or longer is easily attained. Without thermometer, but with Freas mercury thermo-regulator with thermal relay, heating lamps, stirring device and electric motor for 110 volts, 60 cycle, AS Gina he ntio RUAN Nea nye VRC ON nn tes RAO One ay We tie PAP Oi ened Baas ting che ae Neca dll Geren GRU Ac teh 220.00 4015. ditto; but-with motortor: Td 0=volt- dey nic es fades ee A ee eee es Wr ahs a der hs 220.00 4016. Glass Tank, only, for Freas Constant Temperature Bath; 15 inches in diameter by 15 inches deep.. 13.90 CONDUCTIVITY OUTFITS CONDUCTIVITY OUTFIT FOR DETERMINATION OF ABSOLUTE VALUES WITH THE UTMOST ACCURACY. This selection of equipment is largely that described in the Leeds & Northrup Company Catalogue No. 48, developed as a result of the work of Dr. E. W. Washburn, of the University of Illinois, and described by him in the Journal of the American Chemical Society, 38 : 2431, 1916, and consisting of: 3946. Vreeland Oscillator, L. & N. 4011. Constant Temperature Bath for 110-volt lamp 3958. Kohlrausch Bridge, L. & N. circuit, with 110-volt d.c. motor for stirring device, 3950. Tunable Double Telephone Receiver Rheostat for controlling heating lamp, and Beck- 3966. Curtis Coil Resistance Box, 5 dial, L & N. mann Thermometer with Bureau of Standards 3970. Variable Air Condenser certificate 3971. Vernier Condenser 9372. Double Pole Switch, double throw 3974. Washburn Conductivity Cell, Type A 3975. “ “a “ “oR 3976. “ “ “ « &© 4020. Complete Equipment, as above listed, with sheet-iron shielded base, and with two-conductor armored lead wires attached to same................... peters aspect ee Mord 3 AN ea Ot fa 1168.75 4021. ditto, but with 110-volt, 60-cycle, a.c. motor for the stirring device.......................... 1168.75 4022. Shielded Base, only, as supplied with above outfit, consisting of a wooden base with sheet-iron shielding plate to which is attached two-conductor armored lead wires. A considerable part of the expense of this device is incurred by the attachment of these armored leads........................ 85.00 4023. Armored Lead Wire, Two-Conductor, per foot... .......0 00.00. .25 ho RE eR H. dp Ae Os Mor An Si Cc © MP A N Y CONDUCTIVITY OUTFIT FOR PRECISE MEASUREMENTS == To LINE—>— FOR HEATER | To LINE FOR MOTOR 4024 Conductivity Outfit for Precise Measurements, with diagrammatic illustration of connections. CONDUCTIVITY OUTFIT FOR PRECISE MEASUREMENTS. For a great variety of determinations other than those of absolute values with the utmost accuracy, for which the equipment described on preceding page is recommended, it has been found that the high frequency current from the Audio Oscillator, or Micro- phone Hummer, can be substituted for that of the Vreeland Oscillator and that both the Curtis Coils and the Air Condensers can be omitted. The use of a Constant Temperature Bath is required, suitable for measurements at either 0° C, 25° C, 50° C or 100° C. Because of the difficulties of precise automatic temperature control, we recommend a simple type of bath without automatic regulation, for control by means of a Beckmann thermometer reading to 1/100° C. The maintenance of 0° C requires an ample supply of cracked ice and distilled water, and 100° C a high boiling liquid at proper temperature. The intermediate temperatures are attained by means of the incandescent lamp with regulating resistance. Temperature regulation should be so close that the maximum variation in degrees is not greater than one-half of the allowable percentage error from this source. Only one Conductivity Cell, Type B for medium conductivities, is regularly supplied with the outfit and where a variety of work is likely to be undertaken, we recommend the addition of Cells for high and low conduc- tivities, which will be found listed on page 184. The selection of equipment above illustrated is as follows, the component items of which are all listed and sold separately under their respective catalogue numbers: 3948. Audio Oscillator, or Microphone Hummer 4010. Constant Temperature Bath 3958. Kohlrausch Slide Wire Bridge, L. & N. 9567. Beckmann Thermometer 3950. Tunable Double Telephone Receiver 8715. Rheostat, 630 ohms, 1 ampere 3967. Four Dial Resistance, L&N. 4780. Stirring Device, with motor for 110-volt d.c. 3975. Washburn Conductivity Cell, Type B 2090. Burgess Super-six Dry Cells (3) 4024. ‘Complete:Outhit; as:above Nsted.. 0 esc ke hig bee d oedg Sewn iee ea ew se ta bee gh ee eens 324.00 4025. ditto, but with 110-volt, 60-cycle, a.c. motor for the stirring device..............0-..00 000005 324.00 188 | Kh LECOS & NORTHRUP CO. AMT CO PHILA, 4026 Conductivity Outfit for Measurements of Moderate Accuracy, with diagrammatic illustration of connections. : CONDUCTIVITY OUTFIT FOR MEASUREMENTS OF MODERATE ACCURACY. For determina- tions of moderate accuracy a Conductivity Cell with thermometer obviates the use of any constant temperature bath. Conductivity Cells LC, MC and HC are supplied with a thermometer reading in 1/10° C, which corre- sponds to an average accuracy in measurement of about one-fourth of one per cent, insofar as this accuracy depends upon temperature. For work of this kind the Simplified form of Kohlrausch Slide Wire Bridge is satis- factory, and is recommended because of its low cost as compared with No. 3958. The selection of equipment above illustrated is as follows, the component parts of which are all listed and sold separately under their respective catalogue numbers: 3948. Audio Oscillator, or Microphone Hummer 3980. Type MC Conductivity Cell, with thermometer 3959. Simplified Koklrausch Slide Wire Bridge, L. & N. 9356. Support, for conductivity cell, with clamp and con- 3950. Tunable Double Telephone Receiver nection for wires 3967. Four Dial Resistance, L & N. 2090. Burgess Super-six Dry Cells (3) 4026. Complete: Outfit: asiabove listed <.+) oe dieus ee es bl ee eee ete eee cee eee ial weayd eee 201.00 ee | Bit | | | i Unmnmna g3 ay 1y/, Ms 7 Ky " f. 1 - =I N +H.T.Co.PHILA. 4027 Conductivity Outfit for Educational Use, with diagrammatic illustration of connections. CONDUCTIVITY OUTFIT FOR EDUCATIONAL USE. The Conductivity Cell included in this outfit is a modified form of the original Ostwald Cell mounted in a Dewar flask and, therefore, intended for use without a constant temperature bath. For students’ work a Half-Meter Bridge is preferred by many, as is also an independent source of e.m.f. of high frequency such as can be had from the Audio Oscillator. Where it is desirable to operate several stu- dent’s desk outfits from one source of e.m.f. of high frequency, the Audio Oscillator can be omitted and the Constant Speed High Frequency Motor Generator described on page 180 supplied instead, which has sufficient power to supply as many as ten or twenty desk outfits. The selection of equipment above illustrated is as follows, the component parts of which are all listed and sold separately under their respective catalogue numbers: 3948. Audio Oscillator, or Microphone Hummer 3986. Thermometer, 40° C, for Conductivity Cell 3961. Half-Meter Bridge 9357. Support, rectangular Base 3951. Double Telephone Receiver 3286. Clamp, for wire connections 3967. Four Dial Resistance, L. & N. 3288. Clamp, for conductivity cell 4044. Single Contact Key i 2090. Burgess Super-six Dry Cells (3) 3998. Ostwald Conductivity Cell, with vacuum jacket 4027. Complete Outfit, as above listed................. eiume nine fy ney ae Merervonms aerate ees ame ee 150.50 4028. ditto, but without Audio Oscillator; for use as individual desk outfit connected with common source of e.m.f., such as No. 3947 Constant Speed 1000-cycle Motor Generator................. 118.50 189 A RK T HH U R EL. T° SHO. Me Ay oS Cc O M4f4 P A N Y TO LINE 4029 Conductivity Outfit for Measurements of Moderate Accuracy, utilizing a 60-cycle a.c. circuit as source of e.m.f., with diagrammatic illustration of connections. CONDUCTIVITY OUTFIT FOR MEASUREMENTS OF MODERATE ACCURACY UTILIZING A 60-CYCLE A.C. CIRCUIT AS SOURCE OF E.M.F. A great variety of conductivity measurements can be satisfactorily made with the use of an A.C. Galvanometer and a Wheatstone Bridge in connection with the ordi- nary 60-cycle lighting circuit. In much of such work, it is possible to omit the Constant Temperature Bath by the use of a Conductivity Cell with vacuum wall, as included in this outfit. This arrangement has already been applied to important applications of electrolytic conductivity measurements in chemical laboratories. The selection of equipment above illustrated is as follows, the component parts of which are all listed and sold separately under their respective catalogue numbers: 3952. A.C. Galvanometer, L. & N. 3998. Ostwald Conductivity Cell, with vacuum jacket 3960. Five Dial Wheatstone Bridge, L. & N. 3986. Thermometer, 40° C, for Conductivity cell 4044. Single Contact Key 3286. Clamp, for wire connections 9357. Support, rectangular base 3288. Clamp, for conductivity cell A029: «Complete: Outfit; as above listedi.-.... oc candies Sade ts BASd een Goer aeav amen aE eee ee oS 149.25 4030 Conductivity Titration Outfit utilizing a 60-cycle a.c. circuit as source of e.m.f., with diagrammatic illustration of connections. CONDUCTIVITY TITRATION OUTFIT UTILIZING A 60-CYCLE A.C. CIRCUIT AS SOURCE OF E.M.F. There are certain titrations in which the electrical conductivity of the cell suddenly changes when an ion of high mobility has been displaced by one of low mobility, or vice versa. Such a change in conductivity can be made the basis for determining the end point of the reaction. In making a titration of this kind, the operation consists of using the Kohlrausch Slide Wire with its extension coils “plugged out” of the circuit. The usual Wheatstone Bridge connections are used. Readings are taken and recorded of the amounts of titrating solution added and the corresponding reading on the slide wire. These two sets of readings are plotted on rectangular co- ordinate paper. The point at which a maximum or minimum occurs represents the end point of the titration. The selection of equipment above illustrated is as follows, the component parts of which are all listed and sold separately under their respective catalogue numbers: 3959. Simplified Kohlrausch Slide Wire Bridge, L. & N. 2410. Paired Burettes, 50 ml in 1/10ths, for titrating 3952. A.C. Galvanometer, L. & N. 3222. Clamps, for Burettes and Conductivity Cell (3) 3967. Four Dial Resistance, Box L. & N. 9336. Support, large 4044. Single Contact Key 2110. Beaker, Pyrex glass, 600 ml 3994. Conductivity Cell 4030. Complete Outfit, as above listed 4040 4040. 4041. 4044. 4045. 4046. 4050. 4052. Cone, Imhoff (Settling Glass), specially graduated for testing the amount of suspended material in raw and settled sewage, by the Imhoff method. The cone is of 1 liter capacity, graduated at the point to-40) milanyspecialisubGivisiOnss 2s. sa sek Sorseed ee is A See eee WAUEY hl ie Sean ah led OE Al Soll be 4.60 Wooden Support, specially designed to take one Imhoff Cone .. , : Seats penises 3.50 Contact Key, Single.................... PEARL UE AaR e east Pee RA ET CR REL TEE ORE A PRS ae Ea 5.00 Contact and Short Circuiting Key, Single, for use with d’Arsonval Galvanometers used with zero deflec- ET OISINVE G1 OS ee ci Ge sate sae teat apt oa eos iievalin pay Mend teat oe hunch edhe wa Sol Mea. s puaarntbees ag one Pha ene hte 16.00 Contact. Keys Double:s: 053 2 ns ob as 5 Dak eB ee Se Fegan Sail Se saps acu Mos Rese Amarin 9.00 Corks, XXX quality, regular length. INium Det a gaan weaned ae 0 Al 2 3 4 5 6 t Length, inches........... 3 3 rd 3 ard $ co 1 Top diameter, inches...... 2 6 z % 2 Hn 3 Ts Bottom diameter, inches... 4 Ps = i ae 3 % 3 Per 100........ .38 .38 A7 54 65 76 .85 1.00 Per 500... 1.52 1.52 1.88 2.16 2.60 3.04 3.40 4.00 Number...... : 8 9 10 11 12 13 14 15 Length, inches....... lis 1t 1% 135 ie 11 15 13 Top diameter, inches..... . i 3 1 1lys 1} 13 14 14; Bottom diameter, inches. .. B 4 ae - 43 aL 1 14 Per 100......... 1.00 1.07 1.22 1.32 1.46 1.60 1.86 2.13 Per 500.. 4.00 4.28 4.88 5.28 5.84 6.40 7.44 8.52 Numbers 22 ane ds nds 16 17 18 19 20 22 24 26 Length, inches........... 13 13 13 13 13 13 13 13 Top diameter, inches...... 12 1% 13 14 13 13 12 9 Bottom diameter, inches. . . 13 li 1i 1 13 12 1% 124 Per 100......... ORY as 2.64 2.85 3.06 3.30 3.54 4.01 4.50 4.74 Per5003 ee ere ae ee 10.56 11.40 12.24 13.20 14.16 16.04 18.00 18.96 Corks, Special Laboratory Quality, regular length. These corks are made for laboratory use and are not regularly listed or designated in the cork trade, and because of the wide selection necessary to get homogeneous wood are much more expensive than any corks regularly on the market. They are particularly recommended for use with extraction apparatus, etc. Number caanscneewes sovsctinks age 3 4 5 6 7 8 9 beng theta t sates Sere aus an aeney ees ie a z v5 1 135 12 Top diameter, inches..... ts a oe a ag) 1 13 Bottom diameter, inches. . B is 4 or 5 au 3 Per 100..... 1.00 1.00 1.00 1.00 1.17 1.42 1.75 Per 500. . 4.00 4.00 4.00 4.00 468 5.68 7.00 Number . . 3 ewer 10 11 12 13 14 15 16 Then gthe, 6 eNvccdsee Acie van eeae 1x5 1% 11 1 13, 11 14 Top diameter, inches..... ; 1 1% 1i 1,3. 11 135; 13 Bottom diameter, inches.......... Te Z 18 gL 1 135 11 Pee 100: cccn nc da eonensonvinvaws 2.00 220 241 268 3.10 3.56 4.41 Per 500. . oo 8.00 8.80 «9.64 10.72 :12.40 14.24 :17.64 Number .. Eee sent hes penne Senne 17 18 19 20 22 24 26 Wengehsiens othe sul a sternly 251 Nees 14 13 14 ae 14 11 1h Top diameter, inches......... mae lis 13 13, 15 13 12 5 Bottom diameter, inches.......... ra 1} 145 13 13 > 11: Peril0O erent ae 4.75 5.12 5.53 5.94. 6.50 7.00 7.55 Pergo. are See eee: 19.00 20.48 22.12 23.76 26.00 28.00 30.20 Bn Re SE Ee = eR El T HH © M AS Cc O M 4060 4054. Corks, XXX Quality, short taper. INUMDERs peta ctshee Nok, saat 0 1 2 3 4 5 6 7 AGON Sty pe np eeseeth eocee yreecce a 3g 3 oy 3 3 & i Top diameter, inches...... 3 ik Pe is 3 3 i te Bottom diameter, inches... is 44 3 16 2 is 3 tt Per LOO; pater seca nectar: .36 -36 .40 45 51 -63 -67 .83 Per:500) 45 tke Sao ket 1.44 1.44 1.60 1.80 2.04 2.52 2.68 3.32 Num bers s20-3 640s acd ua vk 8 9 10 11 12 18 14 15 Bengt sie eke teen: 3 3 1 1 1 1 il al Top diameter, inches...... a 13 1 12; 14; 135 1} 1y5 Bottom diameter, inches... a i t te te lis 13 li Per 00sec Sate. Ss neue 1.00 1.00 1.05 1.11 1.22 1.35 1.56 1.79 POR 500 coe cesses sce 4.00 4.00 4.20 4.44 4.88 5.40 6.24 7.16 Num bere gaiig a bt ek ae ose 16 17 18 19 20 22 24 26 Ibength. rk cn ey en sae 1 1 1 1 dl 1 1 1 Top diameter, inches...... yan 123 13 1% Ls 13 5 2 Bottom diameter, inches... 1s 14 1 13 lie 15 1 133 Rer00 eis odo se te 1.92 2.07 2.2. 2.43 2.63 3.09 3.45 4.00 Pere 50078 a3 hanes ners 7.68 8.28 8.96 9.72 10.52 12.00 13.80 16.00 4056. Corks, XXX Selected, so-called ‘“‘specie” or jar corks, very slight taper, 3 inch high. Length, inches................. 3 7 3 3 z 2 Top diameter, inches............ 3 z 1 14 1} 13 Bottom diameter, inches......... 2 3 33 1% 14 ly Per lOOie Sik Ae eens tian 1.03 1.03 1.16 1.42 1.74 2.06 POP 15 OO eres, Hauke Sen one te oe 4.12 4.12 4.64 5.68 6.96 8.24 4058. Corks, XXX Selected, flat, with very slight taper, 2 inch high. Length, inches................. 2 2 8 g 3 3 Top diameter, inches............ 3 2 13 13 2 25 Bottom diameter, inches......... 13 3 12 13 1z 276 Bers On cs tiene ete ora ae 27 31 37 -43 -50 57 Per LOO ssc itis paket ee 2.43 2.89 3.33 3.87 4.50 5.13 Length, inches................. 3 & 2 3 2 7 Top diameter, inches............ 2i 23 23 23 23 2t Bottom diameter, inches......... 23 235 25 24 22 23 Perlis hrnisn en heals & elles -65 74 .83 -96 1.08 1.20 Per 100s os veacs ee oe ec eke esas 5.85 6.66 TAT 8.64 9.72 10.80 4060. Corks, XXX Selected, flat, very slight taper, 3 inch high. Toength; anches:: sa.) 2.4% sek ee 3 3 a 3 3 3 Top diameter, inches............ 3 3t 3 33 4 4y Bottom diameter, inches......... 2; 3h 35 33 3t 476 CMS i Oe eh i ing eet ees 15 19 .23 27 31 37 PROF NO isc Faces neessencu corse eitvah ded el 1.35 1.71 2.07 2.43 2.79 3.33 Length, inches....... i a 3 2 3 a 3 Top diameter, inches. . 43 2 5 a 5B 53 6 Bottom diameter, in... 2 4 413 5a 5+ 58 2 Bach. iii. ake She es -43 -49 -55 63 71 .79 .88 Per N08 see oak oer eee 3.87 4.41 4.95 5.67 6.39 7.11 7.92 4062. Cork, Natural, XXX Quality, in sheets 4 by 12 inches, } inch thick....................0 00. cues 27 4064. Cork Borers, of hard brass. Number of borers in set....... 3 6 9 12 15 Diameter of borers, inches..... vs to zs to vs to 4 4; to 3 4 to; POPS brat saber Macs a eiteena 50 1.00 1 2.60 3.50 10% discount in lots of 12 sets. 4066. Cork Borers, of steel tubing, in sets, with individual handles and punch for each set. 7s Inch in diameter. Borers differ by UNWIND ERASE t Sirs te hastens ee tee ton eon eye Hirde a 3 6 9 Diameter of borers;inchess ..cssetensa aus autos. wks tot 3 to to 5 POE SO be pics wistk yee ere Mange anes Rea gn ald eae A, een a 2.00 3.25 3.50 10% discount in lots of 12 sets. 4068. R 4070. 4071. 4072. 4074. 4076. 4078. 4080. 4088. 4090. 4091. 4092. 4093. T H U_ R H. T H OF M AS Go O05 Me PA IN OY 4078 Cork Borers, of hard-drawn brass tubing. Each borer supplied with handle. A very convenient form. INumberin Seber. sso akin air vs Bn ake cue ioe aniae beacetieln esau 6 9 12 Diameter of borers, inches.................-.000 00000. . toi 7; to 3 zs to 3 POP SO b 4 i.) mires cose oop mines toe Mn 1 seating aN cela ct a inca An 1.05 1.75 2.60 Cork Boring Machine, for either wood corks or rubber stoppers. With eight interchangeable steel borers Proms COne Ne -ClamMeteny. hc cesies co aate heelys cot ck 9 a ey ae csichs aed tele ra river wade ed See a ele 23.00 Attachment for use with No. 4070 Cork Boring Machine, with 23 extra cutters from § to 2 inches diameter, with-holdingdevace satire sheen nah ene iia Rong nena tas Rone tects carte wal Pe dati gunna 3.50 Steel Borers, only, for No. 4070 Cork Boring Machine, for replacement. Sold in sets only. Per set OLB chs ea riatey Sch MO Av nteh ake ack euarwh Monts Minn ent ts Bath Smtuiwn osenert aeth hats Genie tew aotectees el lesa 3.40 Cork Borer Sharpener, a brass cone with steel knife.........0.00 20000000000 ee 65 Cork Press, Rotary. For corks up to 32 mm diameter...............0.0 0.000000 cc eee 1.85 Cork Screw, quick acting, in heavy wooden handle................ 20.00 ccc cee ee .20 Cork Screw, self-pulling, with wire cutter. The most simple and practical cork screw made....... .40 4090 Counter, Hand (Tally Register), Veeder, reading up to 9999 inclusive, with quick set-back, for use in counting blood corpuscles, bacteria, etc...... 200.0000 ete 5.00 Counting Apparatus, Stewart, for counting colonies of bacteria, consisting of a hardwood box 12 by 6 by 8 inches, which contains an incandescent lamp for use on 110-volt lighting circuit and an adjust- able platform for a Petri dish which is illuminated by oblique rays from the lamp which do not enter directly into the eyes of the operator. A ruled glass plate is provided on the top of the box and the counting accomplished by viewing the colonies in the Petri dish through the glass plate. See Journal of Medical Research, January, 1906 2... 000 ee 19.00 Reading Lens only, for Stewart Counting Apparatus.....................0005. Theta wetness 3.00 Incandescent Lamp only, 16 c.p., for 110 volts, for Stewart Counting Apparatus... ............. 50 Ruled Counting Plate only, for Stewart Counting Apparatus................... eaves shack: ie O00 193 4095 4097 4100 4094. Counting Apparatus, Wolffhuegel, for counting colonies of bacteria. The glass plate is 165 mm square, and ruled area is 120 mm square. Complete on wooden base with ruled glass plate, and black andvwhite: backproum dep ncetcledus cients nytt ower eke wee sateen unerae iemiemuar aunge thd ace yt tatta ieee aah Se 9.00 4095. Counting Plate only, of glass, ruled, as used with Wolffhuegel Counting Apparatus............... 1.70 4096. Counting Apparatus, Jeffer, for counting colonies of bacteria. The glass plate is 165 mm square, and ruled area is 132 mm diameter. In this ruling the concentric circles are divided into equal areas and are subdivided by radii into smaller integral areas. The numbers refer to the number of equal sections within the area enclosed by the circle just beneath the number. Within the sectors ‘‘a” and ‘‘b”’ the areas enclosed between the three outer circles are further subdivided into half spaces. See Journal of Applied Microscopy and Laboratory Methods,Vol. 1, No.3. Complete on wooden base with ruled glass plate and black and white backgrounds.............-... 0.000 eee ee eres 11.00 4097. Counting Plate only, of glass, ruled, as used with Jeffer Counting Apparatus.................... 3.70 NoteE—Wolffhuegel and Jeffer glass plates are now made in the same dimensions, and can be used interchangeably on the same base. 4098. Counting Card, Jeffer Ruling, for counting colonies of bacteria, of black cardboard ruled in white lines. .10 10% discount in package containing 25. 4099. Counting Card, Frost Ruling, for counting colonies of bacteria, of good quality Bristol board ruled in white lines. The cross lines divide the figure into square centimeters. Four of these, just above the center, are subdivided. The numbers 40, 60 and 80 give the area of the discs bounded by the circles just below them. The area of each sector ‘‘a”’ and ‘‘b”’ is one-tenth of the area enclosed IDEAS Clr C] eine once tte Me vee WES nett bl al libah at Caos IAS brite Rea ns et ein Aenean ty oath se Sinan eaten 10 10% discount in package containing 25. 4100. Counting Chamber, Howard, for molds, yeasts, etc., similar to Thoma haemacytometer counting chamber, i. e., with a depth of 0.1 mm, without ruling, and with central disc 18 mm in diameter. Complete with one each plane parallel cover glasses 0.6 and 1.0 mm thick, but without case.......... 5.50 4101. Cover Glasses only, 33 x 33 mm, for Howard Counting Chamber. CBT Chem essen mice eee kA oe cel acces Whe sen, nat Lies eins ttt | oe po IeLAgn Nth Reh ie en aes 0.6 1.0 Bla CHI 2 ent erect Temi ey ores ce henny Site an eae ROL OTe ene OTs Si None Bag las Soe ua het geek NA oe 1.00 1.00 3304. Counting Chamber, Levy, with single Fuchs-Rosenthal ruling, for cytological investigations, as in cerebro- spinal fluids. Depth of chamber 0.2 mm instead of 0.1 mm as for blood corpuscles. With two coverglasses; but -withouticases .. 20. ance tee l einem, oo dill ye, Sa A OR A aw bs Oe Be Ae 6.00 3314. ditto, but tested by the Bureau of Standards and engraved with official mark of certification.... 9.00 3305. Counting Chamber, Levy, with single Neubauer ruling and with a depth of 0.02 mm instead of 0.1 mm as for blood count. This is the so-called Helber Counting Chamber, originally designed for the count- ing of blood platelettes but now more widely used in bacteriological work in the control of bacterial vaccines by the counting method. With one No. 3382 Reinforced Precision Cover Glass 0.18 mm thick, this cover glass thickness being necessary to provide for the use of a homogeneous immersion objective frequently required. Without case........0.0. 00000 c cece cece eee ee 14.00 3315. ditto, but tested by the Bureau of Standards and engraved with the official mark of certification 18.00 Counting Chambers, Haemacytometer, with illustration and more detailed description of above, see page 137. 6350. Counting Glass, consisting of two plano-convex lenses, 13-inch lens diameter and of power 3.5X, in vulcanized rubber mounting. Recommended in Standard Methods for Both Water and Milk Analysis, A.P.H.A............. 5.25 6350 194 4103 6843 4104 : COUNTING APPARATUS FOR BACTERIA, BREED AND BREW. A convenient method for the direct enumeration of bacteria in the field of the microscope, particularly adapted for routine examination of samples of fresh milk. See: Standard Methods or the Bacterial Examination of Milk, 3rd Ed., A.P.H.A., 1921, Circular No. 58 of the New York Agricultural Experiment Station, ‘Counting Bacteria by Means of the Microscope”’ by Robert S. Breed and James D. Brew, condensed and reprinted from Technical Bulletin No. 49,1916. Circular No. 58 includes an extended bibliography in connection with this method of bacteria counting. 4102. Pipette, Capillary, without bulb, capacity 0.01 ml, calibrated in accordance with the specifications of the authors to deliver 0.01 ml of milk, sp. gr. 1.082 at 20°C... eee 1.20 4103. Micro Slide (Guide Plate), for use in preparing milk smears according to the method of Breed and Brew. Consists of a glass plate 2 x 4} inches with sixteen square-centimeter areas, the remainder of the plate being etched by sand blast. For placing under the slide on which the smear has been TA GO rays Soe eatin nae ale atencccnnte eeu mea A MeN needs C ee enee hss a HE PMS wm nim me are cies Aen eaten ey’ -60 6843. Ocular Micrometer Disc, for use with Bausch & Lomb Ocular 6.4X when count is to be made in the central portion only of the microscope field; with ruled circle 8 mm diameter divided into four quadrants. For counting bacteria according to the method of Breed and Brew; also recommended in Pro- visional Report of the Laboratory Section of the American Public Health Association, Standard Methods of Bacteriological Analysis of Milk, 1916........0 00.00 0000 3.50 6850. Stage Micrometer, for use in measuring the diameter of the field of the microscope. Ruled to 0.1mm ati OOM sama rin eee ale oie nie a eek Eke de er ie earner Ine are a ae Oe aA he Peet et al hoy Wee wn eke ak 5.00 Technique: The technique of this method is briefly as follows: One hundredth of a cubic centimeter of milk or cream is measured in the Capillary Pipette and spread evenly over an area of one square centimeter on a glass slide. In making the preparations the Guide Plate, on which are ruled sixteen square centimeter areas, is placed under the slide upon which the smear is made. After drying, these smears are stained by the method described in detail in the Bulletin, when they are ready for immediate microscopic examination or for filing away. 2 The microscope is standardized by the use of the proper ocular, tube length and objective, so that the area of the microscopic field gives a simple figure for use in computation; thus if the diameter of the field is 0.16 mm measured by use of No. 6850 Stage Microm- eter, the area covered by each field of the microscope is approximately 1/5000 square centimeter (actually 1/4975 square centimeter). Under these conditions, each bacterium seen in a field is equal to 500,000 bacteria per cubic centimeter of milk, or, if the total number of bacteria seen in 100 fields of the microscope are counted, each individual bacterium is equivalent to 5000 per cubic centimeter. Experience has shown that a field giving 300,000 factor is the largest field which can be satisfactorily used. This is secured by ad- justing the draw tube of a Bausch & Lomb microscope to approximately 172 millimeters so that the diameter of the field with a 5X ocular and 1.9 mm objective is 0.205 millimeter. In this case the number of bacteria in a single field of the miscroscope multiplied by 300,000 (actually 302,840) or the total number of bacteria in thirty fields multiplied by 10,000, or the total number of bacteria in 100:fields multiplied by 3000, gives the total number of bacteria per cubic centimeter. When the use of the whole field of the microscope is not satisfactory because of the lack of sharp definition in the periphery (this does not cause serious trouble with the combination above described for the 300,000 factor) the use of the central portion of the field only is provided for by use of the 6.4X ocular and the No. 6843 Ocular Micrometer Dise with a ruled circle 8 mm diameter divided into four quadrants. If, with the use of this ocular, the drawtube is adjusted so that the diameter of the circle becomes 0.146 mm when projected on the slide, the factor necessary for computation becomes 600,000 (actually 597,708). COUNTING APPARATUS FOR BACTERIA, FROST’S MICRO OR LITTLE PLATE METHOD. Counts of bacteria in milk are possible by this method in a few hours and have been found reasonably close to results obtained by the Koch plate method. It has been found that the incubation period can be extended 16 and even 24 hours without affecting the count. It is thus possible to make the cultures one day and leave them in the incubator until a convenient time the next day. The special apparatus needed has recently been standardized, and a portable outfit devised in which a carrying case is combined with an incubator for field use. For latest description of the author’s technique, see “Improved Technique for the Micro or Little Plate Method of Counting Bacteria in Milk,” by Dr. W. D. Frost, Journal of Infectious Diseases, 28, 2 (February), 1921. The specially devised apparatus only is listed below: 4104. Moist Chamber Cabinet, for 48 slides, with water bath at the bottom and room on the sides for the cir- culation of moisture. The slide rack is removable................. 0.0.00 .00 ccc cee 35.00 4105. Warming Table. A metal box with a flat top in which water is kept at or near the boiling point, for drying slides for five minutes, just below the boiling point of water. With tubulation for ther- TM GTTI@ LED ee athe ween ares eee recat ene rs tee i nT AA tp Conca a ars eared oe, Una ah cide ale hen aoe 25.00 5566. Slide Forceps, for convenient handling of the slides......... 00... eee 2.00 4106: ‘Pipette;-graduated to: ae mle seco ose sg drat ce Ay ni ee ek ee wows Se DS ad eee ake .50 4107... Guide; for ruling the-micro plates: | oA Inch Weight Pounds B7) a So | i | sé] 9s ce ee | ARES | RE BRAUN SIMPLEX CRUSHER sé| . esd te sees bree ies aol ea) Boe Cee | He pee Ge Be] ss] | @ | .2g a 6g} a Box Meles| es |elael|s| 2 | ae 4 ae | ES | Or) Se) ee) ie | é am 4246. 4247. 4248. D> cal ow bo es w bo o bo Simplex Crusher, for hand power. 50) 200 16x14 — 18 | 154] 190} 49 | 74.00 ditto, but for hand and power | | GELVIN Gs ieee ey ue sae ee 100) 200 16x23 ditto, but for power driving, with both tight and loose pulleys..| 100) 200 16x22 6x3 2x3) 194] 13 | 18 162} 197] 49 | 78.00 6x3 2x3] 192] 153} 18 195) 245} 49 | 91.00 ble NIH 204 A R T H U_ R H. T H O M AS C O M P A N Y 4251 4251 Revolving Plate Stationary Plate 4254 4250. Pulverizer, Braun, Type UA, power drive, for general laboratory work, taking material 1-inch mesh, or smaller—as obtained from Chipmunk Crusher—and reducing it to any desired mesh in one grinding. The grinding plates are of a special alloy combining strength and toughness. Will pulverize 1 lb. of quartz ore }-inch mesh in 1 minute to 100 mesh in one operation. Total height 14} inches, width 14 inches, length 23 inches; pulleys 9 by 23 inches, speed 850 r.p.m., power required 1 h.p. Weight, packed for shipment, 275 lbs. With one set of grinding plates................... 149.00 4251. Grinding plates, of special alloy, for Braun Type UA Pulverizer. Per set of two................... 9.00 BRAUN CHIPMUNK CRUSHERS. The vibratory jaw is mounted upon an eccentric at its upper end and rests against a toggle at its lower end. The eccentric imparts a circular or gyratory movement to the upper end while the toggle compels the lower end to describe an arc of a small circle. This motion is both forward and downward and impels the discharge. The bearings are lined with the best phosphor bronze split bushings which can be taken up when slightly worn or renewed when needed. All bearings are provided with grease cups. Type VC Nos. 12 and 14 are the smaller size Crushers. When hand-fed, they will reduce rock from about 2! inches down to } inch and smaller at a rate of from 300 to 400 lbs. per hour, and when fed through a hopper, from 400 to 500 lbs. per hour. Type WC, Nos. 16 and 18, the larger sizes, are intended for handling larger quantities of material. When hand fed, their capacity is from 1000 to 1500 lbs. per hour, and when fed through a hopper, from 1500 to 2000 lbs. per hour. Dimensi ra 3 8 be “a < " OversAll: laches Bowids BRAUN CHIPMUNK CRUSHERS ay gee ie Ss ES 2 4 g | i | 3 | Price B 1 As Blo S/B|/ 8/4 S 4254. Type VC No. 12, for power.............| 400] 16x23] 1. 6x3] 21x3 18] 19 | 19 | 185 235 107.00 4255. «oe 14, for power with tight and loose: pulley S:.-2 ci: sone tide ale walls 400) 16x23} 1 6x3) 2}x3 18 | 22 | 19 215 270 125.00 4256. Type WC No. 16, for power............. 400) 20x38} 2 9x4) 2%x4 22 | 22 | 26 380, 460, 190.00 4257. “« «18, for power with tight and | loose pulleys.................--. 400} 20x3} 2 9x4| 2x4 22 | 25 | 26 425 515 220.00 4260. Milling Machine, Laboratory, Johnson, for taking samples of thin Sheets, wire, resistance ribbon, nails, steel blades and small samples of all kinds that are irregular in shape for use in carbon determina- tions in iron and steel analysis. eb sbek 2 asl eOseseta aeope ne ane ayn eM ace Neg meh Toa ate UCIECT sea ACUE ONS et aut 60.00 4261. Cutters, only, for Johnson Milling Machine. Each..............0.. 0000. 4.80 205 4264 4264. 4266. 4267. 4268. 4269. 4270. 4271. 4272. 4273. 4274. 4268 4281 4282 Mill, Porcelain, with grinding surfaces 170 mm diameter of hard acid-proof porcelain, suitable for grinding chemical salts and other material, either wet or dry, to a fine powder. As the funnel is porcelain lined, the material does not come in contact with any metallic surfaces, thereby obviating possi- bility of contamination or color change in ground product.....................0 00000005 40.00 Mill, Laboratory. A compact hand-power mill for laboratory use in grinding chemicals, drugs, gums as well as heavier minerals and metals in the dry state. By the use of a different worm and plates it will grind all kinds of wet and oily substances. Capacity one to 10 lbs. per hour at a speed of 30 to 50 r.p.m. Complete with plates and worms for both wet and dry substances.......... 9.00 Toothed Worm, only, for dry substances, as supplied with No. 4265 Mill. Each................ 1.25 Plain Worm, only, for wet substances, as supplied with No. 4265 Mill. Each.................. 1.25 Mill, Laboratory, Electric, identical with above but with directly connected electric drive; complete with grinding unit consisting of toothed worm for dry material and plain worm for wet and oily material, with movable grinding plates attached. With motor for 110 volt d.c.......... 155.00 ditto, but with motor for 110 volt, 60 cycle, ac... 0... ee 160.00 Grinding Unit, only, for interchangeable use in electric mill; with toothed worm for dry material 8.00 ditto, but with plain worm for wet and oily material....... ee Aen paca ia att wet ey Oh een 8.00 Toothed Worm, only, for dry material; for use on electric mill............... ae kes eee 2.00 Plain Worm, only, for wet and oily material; for use on electric mill......................... 2.00 Grinding Plates, only, consisting of one stationary and one removable plate. Per pair......... 1.50 Granulating and Pulverizing Mills, widely used in leather laboratories, cotton seed oil laboratories, etc., for preparation of laboratory samples. Height 20 inches, length 15 inches, weight 60 lbs., pulleys 10 by 13 inches. Should be operated for granulating at not over 400 r.p.m., for pulverizing at not over 250 r.p.m. Power required for granulating + h.p., for pulverizing + h.p. Can be regulated to grind coarse or fine while running. 4277. 4278. 4279. 4280. 4281. 4282. Mill, as described above, with pulverizing discs......... 0.00000 ene 45.00 at ee beh fy a BPANUlatingGisCsr ic 2 ues Sec segt canna delete Rend as ein Reet elicsda cet 45.00 Grinders, only, pulverizing. Per pair...............0..00.0 0000.00.00. 00 eee eee Rae R A eth 5.50 ss Pgecan Ula tine ACA heh. ale ew phen yee Mae tte, PU ool DE acpi iene S Mane Nee, eal, Athen ei 3.00 Mills, Drug, for grinding drugs, grains, seeds, etc. Can be regulated to grind to various degrees of fineness. ELeI enti CHESt aac whet vnwht ott Lip YAO tn cetlne cao A tena ues AM 123 15 203 Diameter of wheels, inches.................., eee aetna ae 83 83 10% BC Lice teer eg eee cee ea ae an Rae erg ee ese PII roe outed 8 creed 9.00 11.00 18.00 Grinder, or Meat Chopper, as used in bacteriological laboratories in grinding meat for the preparation of culture media, and in beet sugar laboratories for grinding samples. Capacity, lbs............ SEA ep NEA SPAS Ste a eee eee Pana dea RD 2 3 ATUL ON iheh Steer oops an Mie Sene accra, aN ecree yond SL coe AD tale Bia grocer eas 3.75 4.50 6.50 A R T H U_ R H. T HH © M A <=S C O M P A N_ Y 4283 4284 4283. Bagasse Cutter, for use in cutting or chopping samples for bagasse analysis. With automatic feed by which shavings can be cut from the thickness of tissue paper to | inch. As widely used in the SUPAar INGUS Uy MUA ae iene aerate hae OnG lB Mh fy tn nN coy cs Cagle CON eae ae Wh Saint cre 22.00 4284. Mill, Sugar Cane, Hand Power, originally designed for use in plantation and experiment station labora- tories where small quantities of cane are to be handled for analysis. Constructed with special care, being complete miniature of the large type mills. The rolls are 4 inches diameter, 4 inches long, and the mill will handle three-quarters of a ton of cane in twelve hours. Approximate shipping weight 275 lbs. Can be safely packed for mule back transportation when so ordered...... 63.00 ml | i ail 4285 4285. Disintegrator, Laboratory, Warmouth-Hyatt, for preparing sugar cane, bagasse, sugar beet and all fibrous material for laboratory analysis. This machine is widely used in cane sugar laboratories for reduc- ing sugar cane to fine fibre and sawdust. It will reduce almost any plant stalk or fleshy root to a state of fine division for analysis. The machine should be erected on a substantial frame at a suitable height from the floor, and can be driven by a belt from any convenient countershaft. It is provided with a 6-inch crown-face pulley, and to obtain best results should be run at a speed of 1500 r.p.m. Power required from 1 to 2h. p., depending on the work. Witha2h. p. motor and a 6-inch belt, the machine will handle as many full stalks of cane as can be crowded into it by hand. The machine occupies a floor space of about 34 x 34 inches, and weighs net 375 lbs., packed forexport:450 Ibsiivr. gach dace gone a avns eevee arse ace dence Sco unce ven eumntige eielae ees 415.00 4286. Bacteria Grinder, White, consisting of glass globe with ground-in stopper and with charge of agate marbles. Widely used for experimental work in bacteriological laboratories. Glass globes may be sterilized with charge of marbles in position............00 000. c eee ete eee eee 47.00 ADRT Glass Globe jOM Var cca csr ccs ects yet ak GL ed nae AN ARR ntl OMI ae atid ee eau bnen ere viendo an mat S are 12.00 4288. “Marbles only: per box of 252 fo. cis cc octsreteenieittes eee nists nue nate Meranda ae enee eet mete es 13.50 Te Or OR H.. T H O M A S C O M P A N _ Y 4290. 4291. 4292. 4294. 4295. 4296. 4297. 4298. 4300. 4302. 4303. 4304. Ball Mill, Single Specimen, consisting of a porcelain jar with charge of flint pebbles 3 to 1 inch diameter. Capacity of porcelain jar } oz. to 14 lbs. at a charge, dry, (using sand as a unit) capacity 1 quart, wet charge. The porcelain jar measures outside 5.2 by 5.7 inches. Occupies floor space 9 by 11 inches. Weight 50 lbs. Size of pulley 9 by 1 inch. Should be driven at 80-120 r.p.m....... 22.00 Porcelain Jar, only, for No. 4290 Ball Mill, without pebbles, gasket or fitting, but with cover.... 7.50 Porcelain Jar, for No. 4290 Ball Mill, complete with cover, gasket, fitting and full charge of flint DCTS CS Seva ssrag take see AU te ek Pesci i erty og bein oe cena PU wR A RAIA at Nn aera we late Uh den be he oe el cae 8.37 Ball Mill, Single Assay, Type A, consisting of a porcelain jar with charge of flint pebbles ? to 14 inch diameter. Capacity of porcelain jar 1 oz. to 5 lbs. at a charge, dry, (using sand as a unit) capacity 1 gallon, wet charge. Porcelain jar measures outside 8.75 by 9.65 inches. Occupies floor space 14 by 25 inches, height 19 inches. Weight 125 lbs. Size of pulley 9 by 1 inch. Should be driven ATE O OE Torch atieh tre scrim mga a he resets a teaeen teas kamal dare arpa shee tala dad eh usando, ao Ak uiglg Hla ere eisai eae 50.00 Porcelain Jar, only, for No. 4294 Ball Mill, without pebbles, gasket or fitting, but with cover...... 14.50 Porcelain Jar, for No. 4294 Ball Mill, complete with cover, gasket, fitting and full charge of flint DED DOSS ie rest iccok oo cre iomnen wn ceed, cochbeh agus Gru a kets Ge eeeMtauas wn on rea Seo tue thet Opie apie 17.55 Porcelain Pebbles, for No. 4290 and No. 4294 Ball Mills. DD IAMELER; MMNCHESH wear custo dinihale PACs eamiheey Bos 3 3 1 13 2 ier Deegan ryecctenionte Min acuta nonce tau Srna ei Be OY 75 -70 .60 .30 25 Flint Pebbles, for No. 4290 and 4294 Ball Mills. SIZE raz re ator teaey ven iota for cole eg re ee oes os ee Oe Cen eee Ae Meet UPA Ae Ee Small Large Approximate diameter, inches... . ee ce eh ee a il states en) en ae 4tol 2tol} PCRS syags ee tak wee Perth re lai Rest derail Sree ret ee I Aad ee tes 10 -10 SS, ii i l | ea Mh eit 4300 Jar, Bacteria Grinding, Army Medical School Model, of Pyrex glass, as designed and used for the manu- facture of vaccines in the U.S. Army. Dimensions 93 inches high over all, 9 inches outside diameter, neck ground flat on top, and with inside diameter of neck 1 to 1; inches. With very heavy wall and with round corners inside and outside. This Jar will fit any ball mill with a minimum frame clearance of 975 inches or, better, 94 inches. Many frames now in use are exactly 9 inches, which does not permit easy insertion of jars without filing of frame. Each, without rubber stopper or-steell ball sis sys semem a acide tredeteay see ee cna actos boua Ree cathe na Ge ea 12.20 10% discount in barrel containing 6 Jars. Bacteria Grinder, Single Jar, with one Pyrex jar No. 4300, with 9 by 1 inch pulley for motor and handle for hand drive. This mill requires a motor of about } h.p., with worm gear and worm to reduce speed of jar to about 75 r.p.m. Without rubber stopper, or steel balls for jar, and without WNLO LOT sal cea eevee enone y PRs) setae Te ea eros IaH SC ae Gels) SME ca aeeeare ea ASP Te awn Ae chats 47.75 dittowbutiwithoutwPyrex ars 3 ack 2 Ae ast 2k 8 mals ote ick At es onc Oe ge ate ieakly mimeror, Werte a gea & 35.50 Balls, of High Carbon Chrome Alloy Steel. Diameter, inches........................ 3 3 Bers OO ge tae Gre en Ay an ey Gh Une geri ee AEN gant te PE ~ 3.00 6.00 Per A OOO ees Grae nS altace rena en eran es oh er cy MIN Dh hapa to avage (ue MIR emia oo 25.00 50.00 Note—In the Army Medical School the grinding charge is varied within very wide limits in accordance with the work to be done. For typhoid work a charge consisting of from 35 to 70 one-half inch steel balls and from 25 to 50 three-eighth inch balls has been found to be the most satisfactory. 208 4306. 4307. Bacteria Grinder, Triple Jar, with three Pyrex jars No. 4300, with 9 x 1 inch tight and loose pulleys for motor. This mill requires a motor of about } h.p., with worm gear and worm to reduce speed of _ jar to about 75 r.p.m. Without rubber stoppers or steel balls for jars, and without motor.. 93.00 Gittor but ewith OULIP VEX ans) k «cadens VOTE lh pote elec marek hera in sdb a2 OA cea vee ee a dae Oe ind 56.50 CRYOSCOPES. The determination of osmotic pressure by observation of the lowering of the freezing point, which in turn is. proportional to the molecular concentration of the solution, has found considerable applica- tion in biological chemistry, not only in connection with the investigation of the various body fluids such as blood, urine, pancreatic juices, bile, etc., but in the routine examination of milk. We offer No. 4314 Simplified Cryoscope for general work in physiological chemistry, and No. 4316 Hortvet Cryoscope, a more modern and specialized apparatus, which while designed primarily for the routine examination of milk is finding an increased application to other bio-chemical problems. 4314. 7272. 7273. 4316. 4317. 4318. 4319. A more elaborate arrangement is to be had in our No. 7260 Beckmann Molecular Weight Apparatus. Cryoscope, for physiological and clinical work. A simplified molecular weight apparatus, designed for small quantities of solution, only 1.5 ml being necessary for determination. The molecular weight is determined by measurement of the depression of the freezing point. Complete with special Heidenhain Thermometer No. 7272 as listed below, and platinum stirrer (approximate weight SLs FASTIN) Sera, acecsh ease rap nestehn ce eating acct vieeASae) Les eae ark Se baes Peace espe hlecac isa ae IEAt Chalinad aemaer a cera 36.50 Thermometer, Heidenhain, specially designed for study involving the depression of the freezing point. With enclosed glass scale reading 1/100° from +1° to —5° C. For many purposes this thermometer is more convenient than the Beckmann, or Differential Thermometer, inasmuch as it requires no setting when used for work within its stated range. Total length 500 mm...... 12.00 ditto, but with Bureau of Standards certificate..........0 0.00 24.00 Cryoscope, Hortvet, complete outfit, arranged primarily for the rapid and accurate freezing point determi- nation of samples of market milk. See Journal of Industrial and Engineering Chemistry, 13: 3 (1921). With thermometers, bibliography, and directions for use.....................4.. 75.00 ditto, a simplified outfit consisting of Cryoscope only, rubber bulb, funnel tube and two test tubes, but not including thermometers and other accessories............... 0000 e cece eee e eee 30.00 Thermometer, Cryoscope, graduated from +1° to —2° C, in 1/100° divisions................... 20.00 ditto; the control thermometer for guarding against excessive super-cooling and the consequent too low convergence temperature. Graduated from +380° to —30° C, in 1° divisions....... 6.00 209 Ao oR. Ws IK Hi. TT F--O UMA CS Cc O M P A N _ Y CULTURE DISHES In our listing, the designation ‘‘ Petri’? Dishes is restricted to dishes of 100 mm diameter eigen nes is i =e} aa banc 4330 CO SS nl iy all Hy wae” 4338 4340 4330. Culture Dishes, Petri, of glass, fitted in pairs. The 100 x 10 mm size is the standard Petri dish for bacteriological work throughout the U. S.; but as there is an increasing demand for a deeper dish, we are also supplying 100 x 15 mm dishes under this number. The bottoms are exactly 95 mm outside diameter and can be used with Clay Covers, 97 mm inside diameter, and the tops can be used with Clay Covers, 103 mm inside diameter. The tops and bottoms are also offered sepa- rately under No. 4332 and No. 4333 where the complete dish is not desired. Outside:diameter-of tops MiIMmirs ve ene) 2 lk Gage eee ape REA RS 4 ole hcas fe 100 100 Qutsidetdepths mimieiese soe Seek wis Yo ie ee Pace e eats wean Sete eters 10 15 Outside diameter of bottom; mm. o: Gack = secoteecn ns hte ok ee Re 95 95 PGT DAME cos cy th eck eR Stes ta odes eae ht EE Sh cats eee Ge edi ere A cl are Ai 25 25 10% discount in cartons containing 1 dozen. 20% discount in cases containing 1 gross. 4332. Culture Dishes, Petri, bottom glass only; suitable for use with Clay Covers, 97 mm inside diameter. Outside diameter, mm............... Pade ee tries Ree Ry ea ee ORO MEN NEEL a Nps oe 95 95 Depth sami cack. 6 Soya s gouge aed Nouneen ees Be aes canethira stah Sethodhne fa PLe ror st Kees 10 15 Ha Chivcta ya tented ee a dk on cee Prana ed hace Ree Ee ey eat gy ee 12 12 10% discount in cartons containing 1 dozen. 20% discount in cases containing 1 gross. 4333. Culture Dishes, Petri, top glass only; suitable for use with Clay Covers, 103 mm inside diameter. Outsid eral ameter. MMM rrccsccrashe ec ee ceyames eater canmie we eudannye ie eek Geren oe Pe Neu 100 100 Dep Ghestialas ered tc elas Ao eek ely. A eee Al sseaiteese cha ven ee eee SR ees ye eR aaa 10 15 BEACH ira Moe al Sree ah as Bt tess A BS at ie = ie Ue Mama ame atin e Ped a peel Manse arent Wyrd etter 13 13 10% discount in cartons containing 1 dozen. 20% discount in cases containing 1 gross. 4334. Culture Dish Covers, of Porous Red Earthenware, unglazed throughout. The smaller size is supplied to fit the bottoms, and the larger size to fit the tops of, No. 4330 Petri Dishes. Trsidexdiameten mins recy ce eee A ten ark be eh nee one we x ee Neat Shen Bd ra a 97 103 aC hitngi ern hn a eco eeent™ ee a ty tS Eee eR E Sgn ETON Soe cata Hak MORN A hy ts Ato sdk? rnd tie AEE Se oh oo 10 -10 4335. Culture Dish Cover, of Glazed Red Earthenware, 103 mm inside diameter, unglazed inside but glazed on top and sides, thereby reducing evaporations of water from the media, but providing sufficient absorbing surface to take care of water of condensation, etc. The glaze facilitates removal of the marking made with wax pencil. As suggested by C. C. Young, of the Kansas State Water Survey. aCe crc ate oielncts caeslartaaitmvre chin cee ces ciaevi a Aellecia ieint a SUA Go ie AALt yuan seta cam Ad Ahn Wray a Dierendt & ea BAC led 15 10% discount in cartons containing 1 dozen. 20% discount in cases containing 1 gross. 4338. Culture Dish, Gabritschewsky, 100-mm diameter, as originally used for tetanus cultures but as now used for growing tissues in plasma. The culture is made on the under side of the lid. The cir- cular concave portion of the dish serves to collect the products of metabolism falling from the culture, the circular trough around the bottom dish being used for water. By means of the aper- tures provided, a light turn of the lid permits or excludes the entrance of air into the culture com- PATI NUS ete are Wath ek Set hoe) Sh tech te van nmr PD) Chap iadnlne dade eens pane Aeon Nhe ote 1.50 4340. Culture Dish, of polished plate glass, 100 mm diameter by 10 mm deep. The glass rings forming the sides are cemented on in an electric furnace. Because of the use of polished plate glass top and bottom the dish is free from distortion resulting from the blown glass surface of the ordinary Petri dish and on this account is recommended for photo-micrography and for detailed examination of cultures through the microscope. Guaranteed to stand sterilization. Per pair.................. 1.00 4341. Culture Dish, bottom glass only, of No. 4340........0.0.00000000.0.00 00.00.0000 cee ee .60 4342. = “top a pa faces SS APA ipa eee ae peer BRAD PETIT Pew ean ig tr in -60 4344, Culture Dishes, Small, of glass, fitted in pairs. The 75 x 10 mm size is that used in the U. S. Army Medical School for drying the bacterial mass in the preparation of vaccines. This size dish is also used for mixing the serum and bacteria culture in making pneumococcus protection tests and for holding the emulsified sputum in type determinations of pneumococcus by means of the mouse. In common with other small culture dishes, they are sometimes referred to in the literature as “‘Esmarch”’ dishes. Tops and bottoms are not carried in stock separately, nor do we offer clay covers to fit these sizes at the present time. Outside: diameter: of top,:mMs.5 54 65 ce oe ei eck ce ee Bhd nese 50 75 90 Outsidedepth minis orcs caret Stent eer oe) tise tees eon edocs RL a en 10 10 10 OR Pala ee haere yes Dis a ea OR a Rr ges MELEE Meee Pha, 20... 24 ~~—~«.25 10% discount in cartons containing 1 dozen. 20% discount in cases containing 1 gross. 210 . 1 | ——— [Se nS 200x 20mm Antler ELD X Sees 4345. Culture Dishes, Large, of glass, fitted in pairs. Tops and bottoms are not carried in stock separately, nor do we offer Clay Covers to fit these sizes at the present time. Outside diameter of top,mm............... Sse teca ee Mae 120 150 150 200 Outside depth,mm....._. Sees : ; 15 15 20 20 PaGhe aeavc DEON ye Ue cee eer ee ere mee 40 60 70 ~~ 1.00 10°; discount in cartons containing 1 dozen. 20% discount in cases containing 1 gross. Ue x20 mm 4345 4346 4346. Culture Dishes, or Moist Chambers, large double dishes of heavy glass, with loosely fitting cover with knob. Outside diameter of cover, mm............... A ween t= hy sheeted one i was 150 200 240 Inside height, mm.......... Pea ne Pe ee ar : 50 70 80 EACH 2 Oy aha cs a Reet avs wa SEERA y Sgaace nor eae hen deg Ls OU) 1.50 2.50 20°% discount in barrels containing. . plea tik Geek steoen Da sepia rnmeaeenenl seek ae : ae; 60 48 4348. Culture Dishes, or Moist Chambers, large double dishes of heavy glass, with loosely fitting cover without knob. Outside diameter of cover, mm.....................20-220055 eae: 150 200 240 Inside height, mm.......... a HE onsite A ities oid shania dupe leig 2 50 70 80 FCI oh. t 0 sate ahs ected Hee ih Suslies OT Bitemitiett 2 cr ceR att ita kiana eC Bed -90 1.25 2.00 20° discount in barrels containing. . Lois (hak ees MaRS Aaah oe MY Rese 12 60 48 i 4354, 4355 4350. Culture Dish Holder, Ravenel, of spring brass, nickel plated, intended for 100 mm Petri Dishes. The dishes are held securely in stacks of six while in the sterilizer..............00.0......... -70 4352. Culture Dish Holder. A seamless, heavily tinned box 3 inches high by 4,5 inches diameter, taking five 100 x 10 mm culture dishes or four 100 x 15 mm culture dishes. Recommended as a most inex- pensive and satisfactory container for culture dishes during and after sterilization. Each.... .15 10% discount in carton containing 12. 25% discount in case containing 144. 4353. ditto, but larger. These boxes will take culture dishes made up by using the top of the 100 x 10, or 100 x 15 mm Petri dish and a suitable clay cover to fit, this combination being slightly too large for convenient use in the box listed ee oy a size of box 434 x 35%; inches deep....... 20 10% discount in carton containing 12. 7, discount in case containing 72. 4354. Culture Dish Box, of sheet iron. Size 9 inches feat by 43 inches diameter. With removable tray taking fifteen Petri Dishes 100 by 10 mm. Convenient for holding dishes in sterilizer, and for storage of StErilesdiShes sp ccesets 1d APSR OMENU I Babel aie Aas Sousa cu mea Neth Ria nace nal Noel cee tt Asti kena ers ee 3.20 4355. ditto, butof polished: coppers vy ca-¢ cca aeeun dem waaay einate ne hus ead ca ow ee hee 2 ee en nr! 4.40 TUR He Te Or eM Aa SS Co @> Mi Pe A NY 4356. 4357. 4358. 4359. 4360. plat MGUAULA LTE ATA al i = be i . i | | : 4356, 4357 Culture Dish Box, rectangular form, of sheet iron. Size 53 inches by 2 inches by 73 inches high. Will take six 100 by 10 mm Petri Dishes. Convenient both for holding dishes in sterilizer and for SUOrage.of- Steril exdishesiracmrnis aes desrenceses axes eadise wikb mana ace yeh Se ean ean costae ain. Goaenen ee tarhevatten deed 2.00 ditto;“but- of polished :cop peri: =. tat a Wok x na shee ens ey 2 oA ae Sed ok a ace 3.60 Culture Dish Box, with five perforated shelves. Size 8 inches high by 5 inches diameter. Of nickel plated copper. Each shelf will take two 100 by 10 mm Petri Dishes. Convenient for sterilization, and transportation and storage of sterile dishes Culture Dish Box, rectangular form, with five perforated shelves. Size 7 inches high by 5 inches wide by 5 inches deep. Each shelf will take two 100 by 10 mm Petri Dishes.................. 12.40 4360 Culture Dish Carrier, for transporting plate cultures, Model of the Royal British Army Medical Corps, and adopted by the American Expeditionary Forces in France. Consists of a water jacketed copper cylinder in a felt lined wood case. In operation, the water jacket is filled with water at about 45° C, which in the insulated wood case will maintain plate cultures at approximately body tem- perature for several hours. It is invaluable in conducting surveys for meningitis carriers at points distant from the laboratory, as the meningococcus, if chilled, will not grow on plates. In the American Expeditionary Force in France, ‘carrier suspects” frequently had to be cultured in the field, and the plates were satisfactorily sent to and from the laboratory by motorcycle or in open autos in very cold weather. It can also be used for transporting cultures in test tubes, and Board of Health workers and field epidemiologists will find it useful for a variety of work 40.00 212 4366. 4368. 4370. 4372. 4374. 9446. 4370 Culture Flask, (wide mouth Blake bottle) of flint glass, 8 oz. capacity; for use in growing mass cultivations of-bacteriax “Peridozemp aces. vit wos ah octet ws Sacra acd ame oa rd Uk rere cats Sacer ll 1.10 20°% discount in carton containing 72. 25% discount in case containing 288. Culture Flask, Kolle, of Pyrex glass, with indentation in neck to prevent outflow of medium. Flasks are 3 cm deep and 13 cm in diameter, with a capacity of 320 ml. As used in the manufacture of Typhoid-Paratyphoid (A and B) vaccine at the U. S. Army Medical School........... .75 10% discount in case containing 84. Culture Flasks, Miquel, with flat bottom and ground-on cap. Capacity, ml........... _ 50. 100 UAC he ea ke ia pen) ee eet rn TRE a ca wink PRP gre Wnty AN en eta oA GONE ora Cy Mucacee -40 50 Cultire:. Flask; Miquel, pipettesform:,...¢ ¢anad.co aie aiwacka 5 scetee wy Meee Bede ave eee ween -50 Culture Flask, Pasteur, with side tubulations and constricted neck. Capacity ccimly cv sot ame auear ees ce ua dea s eue KOM ARU AEA AE . 100 250 500 1000 RCI Sesh ue ice Peewee as eee ee de hoes otis rey. ea ae 50 -60 80 1.00 Culture Tube, Roux, for potato cultures, 150 by 20 mm. The length measurement is above the con- SETLC UL OM ery cee nce tea hess et ots cee ae ee ts nla e AGATE (a eT ey eee Matin Baas eared ad Wn ed rel hai ah aa 18 10% discount in carton containing 100. . = al = wuigi xX 002 _._ wi SZ X:00Z ww €) X G2 cusses a ° x lo 3 | wugg xOSI _ 3 ° x G 9446 Culture Tubes, heavy wall, without lip, of selected lime glass. Tenpblaiblin «cupid ey penawienes 75 75 85 100 100 100 120 120 120 Outside diameter, mm........... 10 12 13 10 13 15 13 16 18 Per carton of 100................ 1.80 1.90 1.90 1.90 2.06 2.28 2.12 2.28 2.52 20% discount in cases containing... . 1800 1800 1800 1800 1800 1800 1200 1200 1200 Length; Mm. 4.0 os s33 ans dese Ae: 125 150 150 150 150 180 200 200 = 210 Outside diameter,mm........... 13 13 16 18 20 22 15 25 27 Per carton of 100................ 2.10 2.40 2.50 2.70 2.70 5.16 4.00 5.60 6.10 20% discount in cases containing... . 1200 1200 1200 1200 1200 800 800 800 800 Note—For details as to the selection of glass, tolerances, ete., of our Culture Tubes, see page 574. 213 As UR, — OPE Ur UR: Ei T H O M A 8S Gc OO M PP AN VY. =i) "a FO | o1 9450 9450. Culture Tubes, medium heavy wall, without lip. Of Pyrex glass. Packed in cartons containing 100. MOT G Glare MMT oe, Spee ise issue seh ceed de or oetnrsen nace deere ann aS edema ides 100 150 150 200 Outside: diameter mms 2236s shee oe Rah ese es ees ee 13 16 18 25 POT oe iN tea hi pent ness eS ecu tre: fo eae ta a asce aehonat a aes Roars 80 1.00 1.10 2.40 20% discount in carton containing 100. 9471. Culture Tube Filling Attachment, for use in filling culture tubes, flasks, etc. This device prevents con- tact of fluid with the surface of vessel being filled, so that the latter remains clean for the insertion of cotton plug. With rubber tubing and pinchcock 4378. Cups, Porous, of unglazed porcelain. These are cylindrical cells with flat bottom and open top, suitable for battery cells and for other experimental purposes. PGI Onto srinnni ss i. a oc ae eset ld eee Sede nee 15 100 127 177 200 DTATIVEE OTe ATMs 2 62 Aer hse dette Gana set eae acer Rome aro 38 52 76 76 80 a CMe sera See ete ete Pe a eee a Ara i ev amen inne .29 44 .65 .90 1.38 4380. Cupels, Composite, of a special composition, each of the ingredients of which is a perfect absorbent of Lead Oxide. When cold, these cupels are extremely hard and will withstand great abuse, but when heated to approximately one-half the cupeling temperature they become as soft and porous as the most perfect bone ash ues Top diameter, inches........... 1 1} li 13 12 2 Absorbing, grams.............. 10 15 20 30 50 75 Per lOO pits 2 rar teeta (pe ees 2.40 2.70 3.00 3.30 3.60 4.25 10% discount in lots of 1000 4382. Cupels, Bone Ash, of Denver Fire Clay Co. XX Brand, which is a medium fine grade used for general assay work. Top diameter, inches........ 1 13 1} 13 13 2 23 Absorbing, grams........... 10 15 20 30 50 75 150 Per dozen .2...o ny ees cea 30 35 40 45 -50 65 1.00 Per LOO: secon site bhoteen tte 2.25 2.60 3.00 3.40 3.75 4.90 7.50 Bone Ash, for making cupels, see Chemical and Reagent List. 4384. Cupel Moulds, of brass. Size, inches...................0...0000.00... 2 4 3 BAG Lares cn rcreset ted teen in te nc teemny g Nerce See Sah rece aah ree Tn athn POU doe 4.00 4.70 5.50 4386 4386. Cupel Rake, of iron, 24 inches long 4388. Cupel Shovel, of iron, 24 inches long The merchandise listed in this catalogue is described and illustrated without exaggeration and with as much discussion and illustration of underlying principles and details of construction as are | necessary to assure wise selection. The name of the author, with full reference to his publications bearing on the item in question, is given where such data is likely to be of value. 214 A Ry OT oH eR H. rT FH © M A S G -Or Me

y The author’s arrangement for operation COLD WATERY | includes a laboratory reducing gear 48:1 driven by a } h.p. electric motor arranged so that the shaft of the digester operates at about five r.p.m. The author’s procedure in making sugar tests with the Rotary Digester is as follows: 100 grams of chopped bagasse is weighed in a tared cylinder; 1 liter of very hot water is added; the cover, with the cock closed, is placed in position on the cylinder and this is then locked on the hub. If ammonia is used in preserving the material while collecting the sample, no alkali is added to the digestion water, otherwise sodium carbonate is added. The cover is closed and, with the bottom drain open, steam is turned into the casing. Very little steam is needed. With the outlet to the drain open, the pressure is that of the atmosphere. The cylinders 4474 are revolved for an hour in the steam and this is ; then shut off, and the drain is closed; cold water is now admitted and the revolution of the hub is continued until the sample is cooled. The drain is opened and the cylinder is removed, dried and weighed. 4473. Digester, Spencer Rotary, as above described, with the three required and one spare cylinder, valve and pipe fittings as shown in illustration, but without electric motor or speed reducing gear... 225.00 4474, ditto, with No. 7384 Speed Reducing Gear, No. 7374, } h.p. electric motor for 110-volt d.c. and 12 ft. of z-ineh diameter leather belting: 2265 ce 06 agen cases we ack d Gaiden Bw eeu Seo ae ee Ma aes 267.75 4475. ditto, with No. 7358 motor for 110-volt, 60-cycle, a.c......0.0.0 000. c cc eee 268.00 A well-assorted list of equipment for sugar laboratories is to be found under various headings throughout this catalogue. The Digester above listed and the Spencer Electric Oven are important among the new specialties. Our selection of Saccharimeters and tubes, Sugar Flasks, Refractometers, Pulp Balances, Disin- tegrators, Mills, etc., has been made after consultation with competent sugar chemists at home and abroad. 221 A. RT -e ow oR H. T H O M A 5 GC! 2Or SM OR: “A NY PORCELAIN DISHES 4480. Dishes, Coors Porcelain, with spout. Sizes up to and including 110 mm diameter are glazed inside and outside, while the larger sizes are glazed inside only and for a short distance below the rim on the outside. Sizes Nos. 11, 12 and 13 have a heavy, welted rim as shown in illustration of No. 4487. Size number............. 000 00 0 1 2 3 4 5 6 Capacity, ml.............. 35 60 80 100 140 175 210 300 385 Diameter, mm............ 60 70 80 85 90 100 110 120 145 Ba eas Soest s renterdooen ten aah 14 22 .24 36 -42 48 54 -66 84 Size number............. 6a 7 8 8a 9 10 11 12 13 Capacity, ml............. 585 765 1285 1430 2200 3250 5700 10000 16500 Diameter,mm........... 162 185 215 230 265 305 360 400 460 Bach... sicscoe apes eaten e -96 1.08 1.44 1.80 2.16 3.60 4.80 10.80 21.60 4481, Dishes, S. C. P. Porcelain, with spout. Sizes up to and including 120 mm diameter are glazed inside and outside, while the larger sizes are glazed inside only and for a short distance below the rim on the outside. Size number...... 000 00 0 1 2 3 4 5 6 6a Capacity, ml...... 35 60 80 100 140 175 210 300 885 535 Diameter, mm.... 60 70 80 85 90 100 110 120 145 162 Bache. nore 21 .24 -26 .30 .39 -48 57 -66 88 1.00 10% discount in carton containing 50 50 50 25 25 20 10 10 6 6 20% discount in case containing... 300 300 300 150 125 100 100 100 48 48 Size number............. 6b 7 8 8a 9 10 11 12 13 Capacity, ml............. 690 765 1285 1430 2200 3250 5700 10000 16500 Diameter, mm........... 170 185 215 230 265 305 360 400 460 Baths 3o.cs51clle 3 hae eos 1.10 1.25 1.66 2.10 3.08 4.85 6.60 15.40 26.40 10% discount in carton containing ............ 6 6 3 3 20 %, discount in case con- taining. 5 ese he eh 48 36 24 24 18 12 8 6 6 4484. Dishes, S. C. P. Porcelain, shallow form with spout, glazed inside and outside with exception of bottom surface. Size number 2.22.¢2¢.c2e0esee0 e028 1 2 3 4 5 6 iC Ta Capacity, mliwnAsgee vata eens es 45 60 95 160 200 350 550 600 Diameter, MM )..53 2548 es eh oes ees 70 80 95 105 120 140 160 160 ACH irre renege net um ser eae eterna Meee -26 we -48 57 -70 92 1.14 1.22 10% discount in carton containing. . . 50 40 25 20 10 10 10 10 20% discount in case containing..... 300 240 150 120 80 80 80 60 Metric quantity specifications for items listed and packed on the dozen basis, and vice versa, result in unnecessary delay in shipment and tend to retard, rather than advance, the universal adoption of the metric system in commerce and trade. We favor the use of the metric system wherever practica- ble, but encounter many difficulties in the way of its rapid adoption because of the use of automatic machines for the making of standard cartons and boxes, and long established practice in trades other than those connected with the Laboratory Apparatus business and finally, because of many items which pack better by dozens than by tens. For example, certain articles pack in a carton of satisfactory shape in three rows of four, rather than in one row of ten or two rows of five pieces. 222 A} R T H U_ R H. T H O M A _S Cc O M P A N_ Y 4487 4489 4490 4486. Dishes, Coors Porcelain, without spout. With straight sides and flat bottom; glazed throughout; as used in milk analysis. SIZEMUM DEM os Heb ok et Da a ee 43 hie ele ie nae da hi ae BO oot A Be 1 3 4 Capacity calls encye cra lcqchaons cechan eat cetera acon nae REC een tein (arene 13 25 45 DTaMe Ger MIN a sh ae as ee eaten, eke ening ee) oh oa ese 45 69 72 DY) ae eet ed ae Pan Yoke teh Mind Esty es eae Seed RSA Lacerta net Sch nt ey Sears eras esa toon bye suede Rete . 30 -42 -48 4487. Dish, Porcelain, glazed inside only, with heavy welted rim; as used by manufacturing chemists for crystallizations, etc., for which purpose they are especially made. Capacity 24 liters, diameter GOO omATT iis elie pu BA traly el Se yt tgs ass can eaten aah Anum: eh euMeya ees Sh adhe eee ets 30.00 4489. Dish, Porcelain, glazed inside only, with heavy welted rim; a deep form used by manufacturing chemists for crystallizations, etc., for which purpose they are apeciels: made. Diameter 430 mm, depth 305 mm, capacity 25 liters. . Be RAY Scot ak bee rene ret een Note ....... 380.00 4490. Dish, Coors Porcelain, deep form with long spout; glazed inside and for a short distance below the rim on the outside. As used in the cataract process of acid concentration. Outside diameter 320 mm, height 140 mm, capacity 3250 ml 11.70 ee SILLC A 4494 4498 4494. Dishes, Opaque Silica, Glazed, with spout and round bottom. Diameter: inches*).4)c5s.06 ie os ok oe hg ee he 2 2 t zt 4} 53 5k ‘Approx: capacity, 24.cs..0c 2eac Ses euea ve hie ahs 25 45 80 §=6©100 200 400 500 RCM sae he een ents aginst aS eos eet ee aN 1.35 1.50 1.65 2.15 2.50 6.15 6.35 4495. Dishes, Transparent Silica, with spout and round bottom. TI AMELEL; AN CHES -foceeteae Sone tenia ond Uh chee IR scetioon may yen 2 22 a 34 Approx: -capacityerml. 6204 la a saad oe badass Bae Mean pane 25 45 80 100 ACM oak ere eccnclia See cians yearn aint Ne Sorsditn ease ele SRN atlncs ERR ares 2.80 4.70 6.90 7.80 4496. Dishes, Opaque Silica, Glazed, with spout and flat bottom. Diameter cinchesy, ....ccch¢ he sans aver elan martina ens aula a t 3 43 Approx. CADACIEVs, Mab xc 002 a5, 9 Secs oases eae a ese apa 20 30 75 150 Bache: eosin ee cea Re en ee eee a as 1.50 1.65 1.85 2.50 4497. Dishes, Transparent Silica, with spout and flattened bottom. Diameter; ine@hess <4 aos sis aynjeaiegs: Pade eG este nae ahace aie a Ne hp RE A ae 3 2t Approx. capacity; mals. are vei cea he aes Ras bo tected aks Basra ble 20 30 RCH a ies ee aaa ase ON IA ete BN tev ta ted SINAN a tate SUD ey aiscea sete an tae eee aree 3.15 4.70 4498. Dishes, Opaque Silica, Glazed, without lip, shallow flat form; as used for ash determinations, ignitions, etc., instead of platinum dishes. Diameter; An Chesic i .cosee were deeded eae 13 13 2 Qt 23 23 Approx. capacity, ml...................... 10 15 20 30 35 40 aC Die oars Serena bees Socks cad a aah eerie Gree 85 85 1.15 1.15 1.35 1.65 4500. Dishes, Transparent Silica, without lip, shallow flat form. (See illustration on page 224.) Diameters AN CHes «a ase.c.1n8 Gate cel ensceshe Baw ave ors resnd hia hee naseds Nuswine Sewedadnaita seucataehe 13 1} 2 AP PPOXe CAPAClty IML ees sence ek tetee Geers esiotd halt @ Mineo Manuel ove avaneuesomien’ 10 15 20 ACH ses oi ocr ks eae RR Se ES EOS A RS ES Oe eS 2.50 2.80 3.15 A R T H U R H. T H O M A S Cc O M P A N Y 4500 4502 4504 4502. Dish, Opaque Silica, Glazed, for sugar analysis, of exactly the same shape and dimensions of platinum dishes usually used for this purpose, 7. ¢., 2 inches diameter by 1 inch deep, approximately 40 ml capacity. Flattened on bottom, without lip... 2.2...) . eee cece eee ee 1.65 4503. Dish, Opaque Silica, Glazed, for tannin analysis, 3} inches diameter, 1 inch deep, approximately 75 ml capacity. Flattened on bottom, without lip.... 2.0... eee eee eee eee eee eee eee 1.65 4504. Dish, Opaque Silica, Glazed, with handle. A duplicate of the platinum capsule used for direct ash deter- mination in sugar laboratories. Diameter at top 2 inches, depth { inch, approximate capacity, 380ml. Handle projécts 2 inch... 4... kee ee ed Ce ed eee Eee ee ele pees 1.65 i | S:2749 190*x 100mm | 170 x 90mm Antes 4507 4506. Dishes, Crystallizing, of glass, low form, with fire polished edges. Diameter MMs. awcecscnds Ha a cet eeeee Suan 90 100 125 150 170 190 Vera teMiIMeerosha scat eg acge cs eect ties Sees 50 50 65 75 90 100 Ba cht cece seas ed eee eh eect Ae le areca e 16 20 36 48 64 .80 4507. ditto, but of Pyrex glass...................-.. 45 .55 .85 1.15 1.25 1.50 4508. Dish, Tanning, of thin blown glass with polished edge, as used in tanning laboratories. Height 50 mm, diameter 70 mm., approximate weight 35 grams. Each................-.-.-...ee +2005 25 10% discount in case containing 12. 20° % discount in case containing 144. 4509. Dish, Tanning, Pyrex Glass, otherwise identical in specifications with the preceding dish........ 45 10% discount in case containing 36. 4510. Dishes, Evaporating, Pyrex Glass, with spout and slightly flattened bottom. DAME COs IMIS vcs eked ikea Sia nuatatentoce te eeaetns 80 90 100 125 150 200 LOT abst Mi Miler ale Se cree Ran es Be eens 45 50 55 65 80 100 Di rene is Wee eine hs eas air gee Ge .35 -40 45 15 1.00 1.30 35x 6Omnm 4512 4513 4514 4512. "Dishes, Preparation, of glass, so-called “American Stender Dishes,” with covers ground on. Convenient for specimens, paraffine embedding, keeping clean micro slides, covers, etc. DD TATIe COTTA es ee ech eee eos ote ak ee HP AAs Nae ane etn 36 50 60 TOL e Heat serrens then eae ea nace ese Ned emer ar ete nur eh ert ofan ae eae lee 24 30 35 ACH ik acne te be enn G8 fale rabtine aati a uy aan ae ae sane atlel oie alta 25 .30 .40 _ 10% discount in cases containing 144. 4513. ditto, but diameter 60 mm, height 90 mm. Convenient for use in keeping clean slides, etc...... 40 10% discount in cases containing 144. 4514. Dishes, Stender, of glass, for biological preparations, staining, etc. With covers of polished plate glass accurately ground on. These are the original Stender dishes. TD TAMMC LOT TAI es helt ky ahead austaes ente Wael anited icy eudav er eck ie epee 50 60 80 100 leigh ta mins, i hackers Ae Sia ee cen escenario rs 8 eddy ae tune iets 30 35 40 50 a Chis ee steerer ee eae an ag Oey nay eas Acconci btn a cag 35 40 50 -60 Dishes, Petri, see Culture Dishes, page 210. A R T H U_ R Ets T H O M AS CO M PP A N YY 4515. 4516. 4522. 4524. 4525. 4526. 4527. 4528. i rang B= aor or Dishes, Preparation, of glass, with ground-on cover and slight shoulder. Also convenient for keeping clean cover glasses. | 12 i 4515 4520 Diame vermis ts ue ran de yack ieea teens Minty Net cone aes Pilneve ine Pe ae ae tha eh 65 90 HEL e1 Sn beri i eek eye eccler pee ie nog ane eA Ac aed ce tt ioe Set cai ea 40 55 BACH eaten viral emreti ices art iae Sheen erin nay Mae at at aa hy Orman si oy Meet Sane Nees eye -60 1.10 10:7 discount in:cases: CONnEAIMING so. stccacu, teas cinch ote iew pecqes Hoy ee tnereneh Wey Rech Reha 300 180 Dish, Preparation, of glass, with shoulder and ground-on lid with knob. Also convenient for keeping clean micro slides; 110 mm diameter by 70 mm high.............0.0.000000 0022 1.20 10% discount in cases containing 144. Dishes, Aluminum, with straight sides and flat bottom, as used in milk analysis. ‘L, Diameter. Inches: cave csqde wishes cis trie ween hoo Simone eke in eens 23 3 35 4 GI She sin Chesham citar wc carat te ede, fea tiem a a I deme aties : _ $ 1 SAG ice attatched SIE yen ais tr Sea U PW in ails PS wah age attr 24 30 .40 48 10% discount in cartons containing 12. Dishes, Aluminum, so-called “‘ Moisture Dishes,” with closely fitting cover, as used in soil laboratories. Diameters mimeo. Gil ain niece Raney on 2, 50 63 70 PLOTS nts MATS. bee ene ptswe Neciaie Suse ten eee Apa 22 44 30 50 15 GAC hie ea net hs Rae Fe ey Ne tha ee oe, er 45 -50 -60 .70 .85 10° discount in cartons containing 12. Dish, Aluminum, with cover and knob, 2 inches diameter by 1 inch deep...................00-- 45 10% discount in carton containing 12. bast 4528 Dish, Aseptic Enamel Ware, of seamless steel, white enameled, blue trimmed. Both acid and fireproof. Diameter42 inches by. 24:inches: deep exs40:3 s:gontee ehee ws ames eee eck haa S Hietaes Cane ieee : Dishes, Incinerating, Alundum, rectangular form, with sloping sides. Of Mixture RA 84, very dense. 5 3 Wen ethan ch essa dees res hfee es P soes re alae cad. en's afteceh an pintt wigan oat ae Ses 43 9F 123 Width Se 7 ig eRe or aca capt aha She Ta Seated ae hie wt Maine ues eckaete swe ee a 43 4 63 MDG Gls Ser Leet ee ite han den ncstnan 2 cena hu Cre dehen ONbne ALIN ABA Real po 3 235 aC I arse tose Sess assy eed es eR enh co Oa eee em Pal ee mB Ae 1.50 3.00 6.00 Dish, Incinerating, Alundum, circular form, of Mixture RA-84, very dense; 23 inches diameter by § ANCHO CEP vhs mca pes et ees ARIS ASH Gun atOSS NGA VER MENA Ea hectares utes Cases Gree eihes Calm aa potarogn genta Dishes, Iron, with white porcelain lining. The enameling is especially adapted for chemical purposes and will resist strong acids. The detachable handles are removed while dish is heated, and provide a convenient and safe method of handling the hot dish. Diameter; InChesi< x5 nee ee oe Bae yl shee ewan 8 13 18 CBDACIEY cakes Nene mugs eu tae uote ranean oie eae esata 1 quart 1 gallon 3 gallons CHS Savers eles Suse Sao sea eee eee Nv gee aed ae seein oes 1.15 2.60 5.60 Dishes, Lead. Diameter, inches................. 2 24 3 4 5 6 Bachiess ty, oer ots et eee hee tthe nadine 10 15 18 -30 -45 -60 5% discount in carton containing 12. 10% discount in carton containing 144. 225 An RE Us -R H. T H O M A 58: C O M P A N Y 4532, 4534 1336 4530. Dishes, Nickel, spherical shape, with spout. This dish is highly polished both inside and out. Diameters in Chess 2 srcid et tree eatcnceva sth ae tots So ean omc ea seers enmanes 23 3t 4 ADPIOxs CAPACI bys: Illy 3 Foc eed clas wife arktoce eatenee orate aoe Mie ae ene Wa Ra 60 80 100 Ba Cyt IG, ook Pcie le ac nen lal oc Mat a ON vane Neen nl meat irs Rua eR eee Ac AT 1.30 2.50 3.70 4532. Dishes, Nickel, with flattened bottom and straight sides; with spout. Diameters in Chess a sce seach Gad atta a dteo eo Behd Oe aE pe nn BE 2 23 3 4 ADPLOx: CapACit Va MM lee Gy ERS SPC OER G0 oR: H . T H O M A 5 C O M P A N _ Y DISTILLING APPARATUS U. S. GOVERNMENT REGULATIONS REGARDING THE SALE OF STILLS (Treasury Depart- ment Decisions No. 2993 and 3068) require the execution before a Notary Public of four declarations to the effect that the Still is not to be used illegally for the production of distilled spirits. One copy must be retained by the purchaser, and the other three returned to us. We then forward two copies to our U.S. Internal Revenue Officer in Philadelphia, with the request that permit on Form 110 be issued, after receipt of which we may ship or deliver the Still. Before the Still is actually put in operation, application must be made by the user to the local U. S. Internal Revenue Officer for registration on Form 26, Revised February, 1920. These regulations apply to Stokes Stills No. 4670 to No. 4678, Barnstead Stills No. 4680 to No. 4688, and Distilling Apparatus Nos. 4690, 4692, 4696, 4698, 4700 (also to Retort or Condenser when ordered separately) and No. 4702. STOKES AUTOMATIC WATER DISTILLING APPARA- TUS. By a patented construction the Stokes Automatic Still accom- plishes two novel results: First—It utilizes the heat generated in the Still for preheating the incoming raw water to the boiling point. By this arrangement a very small quantity of live steam is required to operate the Still after it is once started. Secondly—By preheating the feed water before it enters the distilling chamber, ammonia and other gases, due to impurities in the raw water, are largely liberated and escape into the atmosphere through an opening in the con- denser provided for this purpose. This is a very important feature, for by driving off these gases before the water enters the distilling chamber it prevents their reabsorption by the distilled water. The Stokes Automatic Stills are made in eight sizes; the smallest, No. 0, No. 00 and No. 000, are heated by gas, gasoline burner or steam coil, and the other sizes, Nos. 1 to 5, are heated with live steam. The principle upon which they operate is as follows: The feed or raw water enters at (H), surrounds the condenser tube (C), and serves first to condense the steam generated in the Still (B) as it descends the condenser tubes, converting it into distilled water; in so doing the raw water becomes heated to the boiling point by the time it reaches the top of the condenser, where the ammonia and other gases escape into the air through the opening (F). A part of this feed water escapes over the goose-neck (E) either into a waste- pipe or cistern, and the balance passes into the Still through the passage (M). By referring to the illustration, it will be seen there is a zone of water at the top of the condenser, which being above the outlet to the overflow (G) is not drawn off except to replenish the water in the Still as it evaporates. This zone of water at the top of the condenser is constantly kept boiling by the steam from the Still descending the condenser tubes, and it is here the ammonia and other gases are liberated. The Still is heated by live steam with a pressure of twenty pounds or over, which circulates in the copper coil (D) and serves to boil or evaporate the raw water. The distilled water comes out at (J) and can be piped to any receptacle. The condenser tubes extend to the extreme top of the steam chamber and high above the water level, so there is no danger of water being carried over by steam. The Still can be flushed for cleaning by open- ing a valve connecting with the drain, or, by removing the copper lid on top, the interior can be easily scrubbed. The heating coil is made of copper and will stand a steam pressure of 250 pounds. It is so arranged that it can be detached from the Still for cleaning. This is a very important feature, for scale will form rapidly on any heating surface where hard water is being distilled, and unless the Still is constructed so this scale can be removed quickly the Still soon loses efficiency and ceases to oper- 4678 ate Propely: 3 a e condenser cylinder and distilling chamber are cast iron, STOKES STILL FOR LIVE STEAM HEATING the Jatter galvanized to resist corrosion. The condenser tubes are Diagram showing sectional view of the interior brass, lined both inside and out with block tin. These are held with of: the; still'and connections screw ferrules so the tubes can be removed if occasion should demand. The manhole cover on the top is copper, tin-lined. These Stills are of the bracket type, as this arrangement offers the greatest economy of space and is more sanitary than mounting them on floor stands. The cost of producing distilled water with the steam apparatus under ordinary conditions is one-fifth to one-quarter of a cent a gallon; this includes the cost of both the steam and water required. The quantity of raw water required to produce each gallon of distilled water depends on the temperature at which the distilled water is delivered by the Still. Under average conditions it requires about eleven gallons of raw water to produce one gallon of distilled. As these Stills are self-contained and require only two connections for water and steam, they can be installed at a very small expense. They are shipped set up ready for connecting the steam and water. The capacity of the steam Stills is based on having live steam of 20 to 40 pounds pressure at the Still. We guarantee these Stills to have the capacities stated above and to deliver pure water, free from any contamination. res Storage Tank No. 9321 of tin-lined copper is recommended for use in connection with these Stills for the convenient storing of the distilled water. 232 4670. 4672. 4674. 2694. 2578. 2592. 4676. 4678. 4670, No. 000 Distilling Apparatus, Stokes, for gas heating, with adjustable burner permitting the use of any kind of gas. SIZ OMINAIT NDC Tea essai ete ope er ea cen ge NAP gp URL ve Phe 0 00 one Capacity per-hour;callonsecay sensei ee wha acs es etek te ee 4 3 INTIMIDER. OPO UEN OLS teen foe hove Seen ne kee oe con eye emer os ee pee hee 1 2 fe a CH eee eh reese tee cates tn Ol ae Dg phys Antennae ONES ti ok Ae ndMe k cral oa 25.00 27.00 60.00 Distilling Apparatus, Stokes, for steam heating, small model, similar to No. 4670, but for heating by means of steam coil inside of boiling chamber. For operation on 25 lbs. steam pressure. In no case should the pressure exceed 30 lbs. SIZELN UMEDA ioe cessor oct heey neat 2 Spa tain deen tate Bye aR Bea cae eagrunie See eho 00 000 Capacity per hourygallonsy seis Ge aiatacheve a th sud cone eR ee Oa) eon es 1 3 CHR hae, ss See ees ae eH URN AE pirate aN Ee Mints RE ait IAG veces Sanat SP Oe 30.00 75.00 Distilling Apparatus, Stokes Combination, U. S. Army Medical Department model, consisting of No. 00 Still with a capacity of 1 gallon per hour, with copper steam coil inside of boiling chamber for heating by connection with high-pressure steam line. With clamp on condenser column for sup- porting any suitable burner for heating where steam connection is not available. We recommend for use with this Combination Still where it is desired to provide for all conditions Kerosene Burner No. 2694, Acetylene Burner No. 2578, or Scimatco Gas Burner No. 2592, but these burners are not included in the price. When used with any of these burners, this Still has a capacity ot : gallon per hour. Price includes gas burner as supplied with No. 4670 31. Burner, Kerosene, ‘‘Khotal,”” burning vaporized kerosene which is automatically generated as fast as needed from ordinary kerosene; gives a hot blue flame without smoke or smell; height 8} inches, diameter of base 9 inches. Burner, Acetylene, consisting of an acetylene burner attached to a cast iron grid, with 6 ft. of cloth-covered rubber hose and union POLPACEE YEN SCY UT OT a cih eases ses caso hla cesta ce eps aig Dae a ae cht IN eas Re ENS Gul Sa eh dedi asec Aachen ate ete . 4.00 Burner, Scimatco Patent, for Gas, constructed on the Méker principle with a metal grid finch deep at top. Adjustable for both cee and air and suitable for use with any kind of gas. Diameter of flame 30 mm 4.25 Distilling Apparatus, Stokes, for gasoline heating, same as No. 4670, No. 0, 3-gallon capacity per hour, equipped with 1-gallon storage tank, connecting iron piping and gasoline burner, with tank arranged to hang on the wall alongside of the Still. Burner consumes one gallon of gasoline in GON“ HOUTS hisors sss Geeaceg ee See eae a ener Ne tac ek Seda ath oweR, Aeon cuca we Manicin ees ee oisketin oe as 37.50 Distilling Apparatus, Stokes, for steam heating, large model, for heating with live steam, as illustrated and described on page 232. For operation on pressures up to 250 lbs. Distilled water is produced with these outfits under ordinary conditions at a cost of one-fifth to one-quarter cent per gallon, and under average conditions eleven gallons of raw water are required to produce one gallon of distilled. The statement of capacity is based on a live steam pressure of from 20 to 40 lbs. at the Still. SizeuNtm Der ei ios peya ck ab Ut ene ee tae semen eye RU REAN aad OA N tiecanl aha tueen nee 1 2 Capacity per hour, ‘gallonsy. cay aja neo t on Qanvaekercoscaea Aly Salento ae a oeeee sie in: 5 10 Weight: lbsiccj 3c .s ce. nccet ce red ea oe ne one sare eee pecan een ge dma mauateoae 275 325 Height. ftes 2 a-cncws aur tara ele aisle Bin RNS mara Sia rashes mT ers ne ua re henner 33 4} Ha chics ice es ones ee es ee hahah guia chs Bs Se Rael GNA ectten pe eet tal aide 150.00 200.00 NoTE—We supply Stokes Steam Stills, large model, for heating with live steam in 25, 60 and 100 gallons per hour capacity on special order, but do not carry them in stock. Prices on application. 233 ss 4680, 4682 BARNSTEAD AUTOMATIC WATER DISTILLING APPARATUS The operation of Barnstead Stills produces distilled water of a high degree of purity, free from ammonia and all gaseous and organic impurities. The construction is such that the heat generated in the Still is used to preheat the incoming raw water. The gas and electric types are portable and can be placed on the laboratory bench or supported on bracket attached to the wall. The boiler of the Still is easily accessible for thorough clean- ing by simply turning the thumb clamps which rigidly hold the condenser and hood. These Stills are shipped set up ready for connecting the water and gas or steam and are, therefore, installed at small expense. Barnstead Gas-heated Stills—Are equipped with radial gas burner incased under the boiler, which re- duces the heat loss to a minimum. These Stills are substantially built of heavy copper, nickel plated, with all parts that come in contact with the water thoroughly coated with pure block tin, and are easily cleaned. Using gas at the rate of $1.00 per thousand cubic feet, this Still produces distilled water at the rate of 14¢ per gallon. Barnstead Electrically-heated Stills—Are identical in construction with the gas-heated type excepting that the Stills are fitted with electric-heating units instead of gas burner. These heating units are so arranged in the boiler that they are surrounded with water, thereby reducing the heat loss to a minimum. The units will last indefinitely if kept covered with water, but are easily replaced by the operator in case of need without return- ing the Still to the factory for repair. Barnstead Steam-heated Stills—Are of slightly different construction from the gas and electrically-heated Stills but the principle of operation is the same. They are constructed of heavy copper and composition, thor- oughly coated with pure block tin on all parts that come in contact with the water, and finished on the outside with galvanized casing. Steam pressure of from 30 to 40 lbs. is required to obtain the capacities designated, but any high pressure up to 150 lbs. may be safely used. The heat generated in the boiler preheats the incoming raw water and reduces the amount of live steam required to operate the Still after it is started. Recommended where large production under continuous operation is required, the cost of operation being but one-fifth cent per gal. 4680. Distilling Apparatus, Barnstead, for heating with illuminating gas only, as above described. Gapacity. per Hour; Gallonsscc8 2 ciacs f ateues slectiasasia dees nanan a 1 13 2 5 Width inches: 2) Aouad 18 18 - 18 24 Space requiréds height. (°° os cosce as earns ae grawniarne are BAAS 24 26 26 48 CLEP UNS Se oie odes sate alte en Ge aa Sean sree ie ees ent 8 9 9 13 Bae i erro res is to aos eats ee ace cpm nls Phere nem ears Mion octet ae 60.50 75.00 96.80 165.00 NotTe—We supply Barnstead Still for gas heating in 10 gallons per hour capacity on special order, but do not carry it in stock. Price on application. 4682. ditto, but fitted with adjustable burner for use on any kind of gas, i. e., coal, natural or gasoline gas. Capacity per hour, Callonsi tcc a acgx pve wo nees a ees aalanen hee one 1 13 2 5 TPVV CHa Geena suits rie chee a el te ates ao cee ee eR VE NEN NE ae 63.00 77.50 99.30 167.50 4684. Distilling Apparatus, Barnstead, for Electric Heating, with switch and pilot board for the 1-gallon size only. As the resistance units for the 1-gallon still require 2400 watts and those for the 2-gallon still 6000 watts for full heat, connection must be made with a line of this capacity and not with an ordinary incandescent lamp socket Gapacity per hour, CallOns x gece aaron aiea Gr actirassouraae de autos a ewue ah Sood harp eealeat eae 1 2 Bachy torsuseroneallOSvoltssx 5 575.2 aa cate aa kg, sea Se wae ey cue oma ante eh hele tae dev eau 9 Atak 75.90 121.00 4685. aitto; butdor use.onc22Z 0 volts, 254 esse ieee hs akon Cte UR an ct ee 75.90 121.00 4686. Heating Units, for Barnstead Electric Stills. These units can be easily replaced by the operator. When used on 220-volt circuit, the units must be connected in series. For Still with capacity per hour, gallons........00..000000 000 cece ccc cece 1 2 Current consumption per unit, watts......00 2000000000 cts 600 1000 Number of units required for complete renewal.....................0 000-0000. 4 6 Per units for 110 violtsi3 = xn tete cas evel ante cd toe ed ate phe Bt eons 6.50 9.00 4688. Distilling Apparatus, Barnstead, for steam heating. Capacity per hour gall ons 22.2.3 sss ori ha Ws cul a arden eee a tans AeA 1 2 7 ENWALCLIG IS ATT CH OS Gace ans eas the ayy See ue oe, notes A Poem ne Aan ens oad 9 9 10 Spacereguired: depth: i "aude eit aerators Weneeyih scceera a: Alen eis 18 20 22 eio Gey coer ee ees ne i acme ene t icy Ment vada t2Ohd 26 27 36 EA Chea cocaine arate etd Oe al Ae Be Sd wie Vo neon, see we, 72.60 104.50 154.00 NoTEeE—We supply Barnstead Stills for steam heating in 10, 15, 20, 25, 50, 75 and 100 gallons per hour capacity on special order, but do not carry them in stock. Prices on application. 234 A R T H U_ R H. T 4690 4690. Distilling Apparatus, for making distilled water by steam heat. Of heavy copper with steam coil near the bottom and provided with an automatic valve which controls the water supply, also water gauge and union for connecting with condenser No. 3932, or other form. apa bys PallOnss. we eect ets eek centre te cea sa tenpeert cate ey Is Ce at are he. erent cana an oy 3 5 1 OF 1 hapa canal a Ete Ponce usec tate Reed te ene Rr ran aes csper herr CANA P trans er her rert anne one en Tt ry ee ee en 43.25 56.00 4692. Distilling Apparatus, Salleron, of copper, complete with alcohol lamp, as used in the determination of alcohol percentages in wine, beer, cider, ete. A Hydrometer No. 6207, Proof and Tralle Scale, and a 100-ml graduated cylinder are usually used in connection with this outfit, but are not included ITs DHE! PEI CE? ots es mctsert aces a Sed sere eee ace ative Aaa Eeose ae lion in leas ahaa ete eee ye ease 13.60 4694. Distilling Apparatus, Regnault, for fractional distillation of small quantities of liquids. Of polished cop- per with burner holder and sliding rack for test tubes, but without test tubes, burner or ther- mometer 54.50 OVERFLOW 4698 4700 4696. Distilling Apparatus, of heavy copper, all seams brazed, intended for high temperatures; with flanges secured by six thumb screw clamps, easily taken apart for cleaning. Capacity, PallOnsx< yon sca awe ae eN A at chen aA meeetinn Wi cretumela ls melee ts t 1 Date ree eer NN eas str MEER gna 2c 2 eA Rencontre ae encanta 43.25 48.00 4698. Distilling Apparatus, Automatic, 11 inches diameter by 13 inches high. Made of heavy spun copper, heavily nickel plated and highly polished. Over a burner using 10 cu. ft. of gas per hour it will deliver 3 quarts per hour. To operate the still, it is placed on a tripod over a Bunsen burner, or other reliable source of heat. Without tripod or any kind of burner.................... 45.00 4700. Distilling Apparatus, consisting of a tin-lined copper retort with zine condenser with block tin worm, re- ceiving funnel for cold water and outlet for hot water. : Capacity, gallons..........- 0. ces e teeter eens 3 1 2 3 5 Balt oes epee he SAN cee i ae eee 15.25 19.25 24.80 32.00 38.50 ACOGRY -“E _n —.U: eR H. T H O M AS Cc O M P A N Y 4704 4702. Distilling Apparatus, for steam, designed for experimental distillation of heavy oils and other liquids or solids requiring agitation with high heat. Capacity; gallonst... 02400 vis vend iotks oe gareaiee cae te 3 1 2; 3 5 alts ese Sater tec Senn sa hee hy ehh A ions nia 20.00 32.00 48.00 56.00 64.00 4704. Distilling Apparatus for Determination of Ammonia in Water. The inlet tube permits the introduction of the permanganate solution into the flask after the distillation of the free ammonia. With mercury seal providing a perfect joint and easy disconnection. ...............0 00000 c eee ee 8.50 4705. Distilling Apparatus, Vacuum, for evaporations or distillations under diminished pressure; consisting of a Pyrex glass dish 4 inches deep by 6} inches inside diameter, about two liters capacity; and a tubu- lated dome of Pyrex glass accurately ground to the lower dish. The 134-inch tubulation in the dome is ground so that a firm tight joint can be made with a rubber stopper. With glass distilla- tion tube and two rubber stoppers, but without thermometer................0. 000000 e eae 8.50 4706. Tube, only, with side neck, for holding thermometer............0.0.00 2.000000 c cece ene 1.00 J) «To VACUUM 4708 4710 4707. Distilling Apparatus, Vacuum, consisting of No. 4705 mounted in cast-iron water bath, porcelain lined, 84 inches inside diameter, with copper concentric rings, 92 inches, and Tripod............. 18.50 4708. Distilling Apparatus, Vacuum, with Condenser, consisting of No. 4707 with the addition of copper con- denser with coil of block tin, vacuum gauge and connection for air pump, supported on a ee bottle, to receive the distillate. Complete as shown in illustration...................0055 0.00 4709. Condenser, only, as above described, without one-liter bottle or distilling apparatus ............. 21. 75 4710. Glass Reservoir, with metal top, tubulations and vacuum gauge. For use with Vacuum Distilling Appa- ratus above described in place of the Condenser, when it is desirable to collect the residue rather than the distillate; without-suppotts.,.c 2.25 .c¢ Gey Saree ys ess as ose, Gu ed eaten baw’ 15.0 T H U R H. T H O M AS Cc A N Y ARP Ey ts 4718, 4719, 4720 4721 4723 4726, 4727 4711. 4712. 4713. 4714. 4715. 4716. 4717. 4718. 4719. 4720. 4721. 4723. 4724, 4726. 4727. Distilling Apparatus, Knorr, as designed and used in the laboratories of the Baltimore Copper Smelting and Rolling Co., for the determination of arsenic, but also found useful for other purposes. Con- sists of a funnel tube with glass stopcock, six flasks with side tube ground to fit both the stopcock and, the: triple-bulb: air Condenser’. 2... cccc2 5 ia cece dung pcauteasdnac kin Shaadadg nas ane Sotto ee 12.00 Distilling Apparatus, Kendall, of fused silica, for the distillation of conductivity water; as designed and used by Prof. James Kendall, of Columbia University. Consists of a three-liter retort of fused silica ware with ground-in connecting tube and transparent quartz flask, 500-ml capacity...... 55.00 Retort, only, of opaque silica, three-liter capacity.......... 0.0 eee ee eee 10.00 Connecting Tube, only. This must be ground to fit the neck of the retort in which it is to be used. . 27.50 Flask, only, of transparent quartz, 500-ml capacity... 1... eee eee 17.50 Distilling Tube, Hempel, for fractional distillation of turpentine. Tube only, without glass beads... 2.25 Distilling Tube, Pyrex Glass, straight with tubulature, approximate length 12 inches, approximate Ciameter Worn Ch 3 e525 sera sso ae mceutaein eee nae wi me rh eae ae ae acannon ate tata naadlars at aind rs 1.00 Distilling Tube, plain form for fractional distillation. ..........0.. 0.0.0.0 eee -20 es ee CMT EN ONES: DULD a isc aides Sho eget ae eae oth eee een de ey oe ae Sega Bea alae acter mere aes .30 es es SSE WO: DUS tec ecesw oie sos ascork etd aoe Cote nasa hanee neater a peta Shed xere Ge teeta 45 Distilling Tube, Glinsky, with glass valves. Teer Brita reschceeae eo ae se ae ay toned each goog obo stata nel eee ual seuaee Bee UA Gee 400 440 480 PEACH sia eeeed segs oe sae, Basar ee ioc pale: eds vase seen ne eee 2.00 2.75 3.50 Distilling Tube, Le Bel-Henninger, with three bulbs............ 2.0... 0c. c cece cence eee eee 1.75 « ee Be oo SE SEOUES So oduct lntne ae peescarnseslte oa no uanasea Nisa na dae iaeeineeers 2.50 Distilling Tube, Wurtz, with two bulbs. Total length 12 inches................. 202.0. ce census 1.40 Distilling Tube, Pyrex Glass, with bulbs and tubulature, approximate length 12 inches............ 1.75 237 ADR: GH 2U- eR H. tT _-H.~O--M: AS C O M P A N Y ee = ean AAA S 5: at ie RPK 4 poe {4 uw 4728 4728. 4729. 4730. 4731. 4732. 7618. 4735. 4730 4731 4729 7618 4735 Distilling Tube, Young, for the distillation of small quantities, with rod and 15 discs. See Trans. CREM SOC TBO DOT Oe secs ols We ws Sieg ew ae nem en aioraek a Ren tate ypan eg Ue le fi eee ene anh 5.50 ditto, but improved form, i. e., with 20 discs, and with 21 constrictions in maintube.......... 8.00 Distilling Tubes, with pear-shaped bulbs in main tube. INUMIbErX OL OU Ses sc da oc oxte ts on oP mt doy eect cabdect ch ane ae Nugent eee eT hs 4 12 ILA CHiis Ses sree trie path Gorse es ot cearid de UR net aL ais Rn ERE redUi No ca ares lahat saat sale ary aks SR Pi 2.30 6.25 Distilling Receiver, Bogert, for fractional distillations under diminished pressure; for taking a large number of fractions of varying volume without interruption of the distillation. Capacity 250 ml. See Journal of Industrial and Engineering Chemistry, September, 1915 12.50 Distilling Receiver, Bruhl, for distillations in vacuum; with ground-on cover, ground-in stopper at top, and glass rod extension for rotating the support, and ground-in stopcock at side. Complete with rotating ‘support-and receiving tubes, ecg ais sae wb bec ete Ses cose Succes Eb actebahius db gues ese 14.00 Distilling Tube Receiver, for the determination of water in petroleum and other organic emulsions by the Bureau of Mines method. See: A Convenient Method for the Determination of Water in Petro- leum and other Organic Emulsions, by E. W. Dean and D. D. Stark, Journal of Industrial and Engi- neering Chemistry, 12, 5: 486 (May) 1920. There is required for this method a No. 5340 Flask 500 ml, a No. 3905 Condenser, 375 mm, and a suitable source of heat. Cenco Electric Heater is convenient: for this purpose. ‘Tube ‘only 2 22.2 6. occ see eee co ode os bis es neers 1.80 Distilling Adapter, for the convenient converting of an ordinary flask into a distilling flask. Diameter of tubulation for insertion in rubber stopper, 11 mm 238 R T H U R HE On OM) ASS Gy sQ> Mc eR Ae INC Y 4737. 3896. 3897. 3840. 4740. 4741. 4742. 4744, 4745. 4746. 4748. 4749. 4750. 4736. Drying Apparatus, Buxton & Beebe, modified by Taylor; for the rapid drying, at low temperatures, of easily decomposed pro- ducts. Of heavy polished copper with motor and burner for heating, which is not shown in the illustration. Price does not include dish. With motor for 110-volt, 60- CYCIE B.Cn en Ones hea le ee Te 200.00 Note—Outfits for other voltages and current supplied on special order. Price on application. Drying Tube, Liebig ee “Vanier, for zinc, being ‘“E”’ of the Vanier Combustion Train.................... - “Vanier, for sulphuric acid, being ‘‘F”’ of the Vanier Combustion Train ss “Vanier Combined Potash Bulb, being ‘“‘G”’ of the Vanier Combustion Train...... 6.00 i | I, \ , - i ' on a Pc: di | ' 4740, 4744, 4748 4754, 4758 Dye Bath, Matthews, for Dry Air. Round, monel metal outer casing, galvanized inner casing, inter- lined with sheet asbestos. The cast-iron top has four openings for beakers 2] inches diameter. Stand is fitted with shield, gas burner with air mixer and cock, heat distributor and galvanized iron, asbestos-lined heat protector. Complete with four spun copper beaker collars with wooden handles and four No. 2104 Porcelain Beakers, 340-ml capacity.....................00 00s 31.20 ditto, but with four No. 2134 Pyrex Glass Beakers, A Oz Sea pacity atcde tis es a eles 28.80 ditto, with four spun copper beaker collars with wooden handles, but without beakers........ 26.40 Dye Bath, Matthews, for Water. Round, heavy copper, double-seamed water pan, tinned inside. Cast- iron top with four openings for beakers 27 inches diameter. Stand is fitted with shield, gas burner with air mixer and cock, heat distributor and galvanized iron, asbestos-lined heat protector. Complete with four spun copper beaker collars with wooden handles, and four No. 2104 Porcelain Bealcerss3402mll CapACItys ac..cas. ees Paes eens ws ee oie a eatyaigtiney seed le sae 28.80 ditto, but with four No. 2134 Pyrex Glass Beakers, 400-ml capacity. ....................... 26.40 ditto, with four spun copper beaker collars with wooden handles, but without beakers........ 24.00 Dye Bath, Matthews, for Glycerine, or Calcium Chloride. Round, extra heavy copper pan with brazed seams, not tinned. The cast-iron top has four openings for beakers 27 inches diameter. Stand is fitted with shield, gas burner with air mixer and cock, heat distributor and galvanized iron, asbestos-lined heat protector. Complete with four spun copper beaker collars with wooden handles, and four No. 2104 Porcelain Beakers, dA0=mnKeapacityn iss -c2ckia ey ohare eres aes 52.80 ditto, but with four No. 2134 Pyrex Glass Beakers, 400-ml capacity.............4.....0s00s 50.40 ditto, with four spun copper beaker collars with wooden handles, but without beakers........ 48.00 Note—The above Dye Baths can be made to heat on steam coil at an increase in price. 239 Ao RE te SI OR He T H O M A _ S CO" -M) PY 2A NY 4754. Dye Bath, Rectangular, for Water. (See illustration on page 239) Heavy copper double-seamed water pan with heavy copper top arranged to hold six beakers 34-inch diameter. The wrought iron stand is fitted with shield, two-line pipe gas burners with air mixers, gas cocks and feed pipe, and ga van- ized iron, asbestos-lined heat protector. Approximate dimensions 18 inches long by 12 inches wide by 10 inches high over all. Complete with six spun copper beaker collars with wooden handles and _ six No. 2106 Porcelain Beakers 425-ml capacity. .........- peasletes Guaee nae Mananatns ee 77.60 4755. ditto, but with six No. 2134 Pyrex Glass Beakers, 600-ml capacity... .. 0.1.0... .. eee eee 69.20 4756. ditto, with six spun copper beaker collars with wooden handles, but without beakers......... 65.00 4758. Dye Bath, Rectangular, for Glycerine or Calcium Chloride. Heavy copper pan with brazed seams, and with heavy copper top arranged to hold six beakers 33 inches diameter. The wrought iron stand is fitted with shield, two-line pipe gas burners with air mixers, gas cocks and feed pipe, and gal- vanized iron, asbestos-lined heat protector. Approximate dimensions 18 inches long by 12 inches wide by 10 inches high over all. Complete with six spun copper beaker collars with wooden handles and six No. 2106 Porcelain Beakers 425-ml capacity... .....-..-. see cece eee eee 132.60 4759. ditto, but with six No. 2134 Pyrex Glass Beakers, 600-ml capacity. ........- 2.2... e eee eee 124.20 4760. ditto, with six spun copper beaker collars with wooden handles, but without beakers......... 120.00 NotE—The above Dye Baths can be made to heat on steam coil at an increase in price. 4764 4766 EBULLIOMETERS for the rapid and convenient determination of the alcoholic content of beverages. The operation of these instruments is based on the variation in boiling point of mixtures of alcohol and water in pro- portion to the amount of alcohol present. The boiling point of water is noted under prevailing conditions of at- mospheric pressure, after which the boiling point of the beverage or other solution to be tested is noted. In the Salleron instrument, the percentage of alcohol by volume of the solution under test is found by means of a sliding scale reading on one side the per cent. alcohol by volume in ordinary beverages with consider- able residue, and on the other side the per cent. of alcohol by volume in a simple mixture of alcohol and water. In the Juerst instrument, the difference between the boiling point of water and the beverage under test is read by means of the simplified tables of Juerst arranged from 0.05 to 7.0% alcohol by volume. A second table is also furnished for comparing the percentage of alcohol by weight with that by volume; and an additional table for the use of those who wish to express the result of their tests in British Proof Spirit terms. The Salleron instrument is used with beverages up to 25% alcohol, after which they must be diluted with a known proportion of water. The Juerst instrument is intended for use with beverages of an alcoholic content of about 7% and below. 4764. Ebulliometer, Dujardin-Salleron, original French make, made and adjusted in accordance with the official standards of the Arts and Trades Conservatory in Paris, and reading in percentage of alcohol by volume, i. €., the legal alcoholometer scale and in degrees of the Malligand Ebullioscope. Of pol- ished copper with burner, all accessories, thermometer, and directions for use...........-- 52.75 4765. Thermometer, Salleron Ebulliometer, as regularly furnished with the original French Dujardin-Salleron Ebulliometer; 330 mm long, engraved on stem, range from 85° to 103° C, in 75° divisions. With maker’s seal, rubber stopper to fit the Ebulliometer, and unofficial certificate of accuracy.... 12.00 4766. Ebulliometer, Juerst Patent, similar in principle and operation to the French instrument but specially adapted for the determination of percentage of alcohol by volume in so-called temperance drinks. Complete in case with thermometer, Juerst simplified alcohol tables reading in percentage of alco- hol by volume, percentage of aleohol by weight, and percentage of alcohol by British Proof Spirit terms, and directions for use 60.00 4767. Thermometer, Juerst Ebulliometer, as furnished with the Juerst Ebulliometer; 400 mm long, engraved on stem, range 13° (from about 90° to 103°C), in 35°. With rubber stopper to fit the Ebulliometer 17.50 240 A R T H U_ R H. T Hh ©O M «& s8 Cc O M P A N _ Y ‘ 7 4 : ie Ht i iy 4772 4773 4774 4776 4772. Electrolytic Support, with japanned iron base, glass upright with ring with three lugs and one clamp, and binding post attached to both ring and OL ATA set tat cc Pe eels tenes dec ar hae eae 3.75 4773. ditto, but with two clamps with binding posts.........0.. 0.0.00. c cee cece ee eee ee ees 5.00 4774. Electrolytic Support, with glass upright carrying clamp and separate glass upright carrying ring... 3.75 ELECTROLYTIC SWITCHBOARD, for the accurate organization and measurement of current from 0 to 5 amperes and e.m.f. from 0 to 15 volts. Particularly designed for use in connection with electrolytic apparatus, and provision is made for two determinations. Consists of a substantial slate panel 18 x 22 inches, with Weston Voltmeter, rating from 0 to 15 volts, Weston Ammeter, 0 to 5 amperes, with adjustable resistance in both voltmeter and ammeter circuits, with snap and knife switches and reversing switch. The switchboards for use on 110 or 220 volt current are supplied with sufficient dead resistance on back of board to bring voltage down to range of meters. For use on accumulator, or other low source of voltage, this is not supplied. The board is supplied with lugs for wall suspension. 4776. Switchboard, Electrolytic, as above described, for operation on accumulator or other low voltage lines up to 15-volt CUCU Gist ite meni eae ona phe cute Seem ninen nek wba 115.00 T 4777, ditto, but for operation on 110-volt d.e......... 115.00 4778. ED DORR ne acne enone: 115.00 4780. Rotating Anode and Stirring Device, consisting of support with motor mounted on adjustable clamp with belt drive to two-groove aluminum pulley attached to shaft pro- vided with adjustable clamp with }-inch opening for glass stirring rods, etc., when same is used as a stirring apparatus. Into this clamp is fitted a rotating anode holder with adjustable chuck for clamping very small wires. In the illustration this anode holder is shown removed from the apparatus. The whole is mounted on a rigid support with base provided with starting switch and rheostat for controlling the speed of the motor from 50 to 1000 r.p.m. The binding posts necessary for electrolysis are attached in a convenient position, but the rheostat is for the motor circuit only and not for the electrolytic current, which must be supplied separately. This is a robust and satisfactory labora- tory device, as the motor has sufficient power to drive other apparatus from the grooved pulley while either stirring operations or electrolysis are being conducted. With motor for 110-volt d.c... 2.2.2... eee 50.00 4781. ditto, but with motor for 110-volt, 60-cycle a.c..... 50.00 AS UR. Fob 0 sR: H. fT H) © M A oS Cc O M P A N _Y rh i ei S 3:0 ji 4784 4786 4784. Rotating Anode Apparatus, Cenco, consisting of Friction Drive Electric Motor with two chucks for direct- attachment of stirring rods or rotating anodes to motor shaft, and with flexible shaft for use when anode or stirring rod is to be rotated in a position other than immediately underneath the motor and with glass stirring rod, and tripod support, 24 inches high. The current specification is for the motor only, and not for the electrolytic current, which must be supplied separately. With INOCORT OK US O=V Olds Casein ews seth Bein apm eds cere he Someta chs ae tor Penccanae Ah tegen ta vant eee erzs 34.00 4785. ditto, but with motor for 110-volt, 60-cycle a.c... 00.0000 een eens 34.00 ELECTROLYTIC OUTFIT, BRAUN, Improved Model equipped with one motor to which a shaft line is connected and each unit is driven by a special friction device enabling the operator to use one, two or more units at onetime. The current through each unit is controlled by an individual switch so that any unit may be connected or disconnected without disturbing any other. Revolving anodes and gauze cathodes are used, giving not only the highest attainable accuracy, but great rapidity of operation as well. The ammeter, line shaft, bearings, switches and other operating parts, are all enclosed in the cabinet to prevent acid fumes from coming into contact with them. The lower portion of the cabinet is covered with alu- minum and the binding posts are also made of the same material, which is resistant to acid fumes. The motor is mounted to one side of the cabinet, the line shaft being connected to it by means of a flexible metallic belt. The speed is regulated by a rheostat. A separate rheostat is used to control the current supplied to the individual units. The outfits are made in sizes having two, four or six units, the latter being the limit of operation with one motor. The motor supplied is universal, in that it operates equally well for this purpose on either 110-volt d.c. or 110-volt, 60-cycle a.c. As d.c. is necessary for electrolysis, a separate d.c. circuit must be supplied when an a.c. circuit is used for the motor. This can be accomplished by storage battery when necessary. As these installa- tions are usually for routine work, it is customary where only a.c. is available to install a Motor Generator Set such as we list under No. 7390, from the d.c. side of which both the motor and the electrolysis current can be drawn. Complete instructions for connection, operation and method of analysis are furnished with each outfit. 4786. Electrolytic Outfit, Braun, as above described, without electrodes but with separate rheostats for the motor and for the electrolysis circuits. For 110-volt d.c. Number Of ainitsyrscrsedy wat oo Ses el NR ease tl ee es eh Ae da 2 4 6 ACI ie spec ys tex cng ate omnes A dopo ce oR aoe moet oe dernier iia a eet rte me a 188.00 217.00 244.00 NoTE—As stated in the descriptive paragraph, the 110-volt d.c. motor supplied with above outfit is universal in that it can also be used on 110-volt, 60-cycle a.c., but in such arrangement a separate d.c. circuit must be provided for the elec- trolysis. In an emergency, the 110-volt d.c. motor and rheostat can be used on 220 volt by placing a 110-volt incandescent lamp in series with the motor, but it is not recommended as a regular procedure. Outfits with 220-volt motors, a.c. or d.c., are supplied only on special order. ELECTRODES. The anodes recommended for the Braun Electrolytic Outfit are made in the shape of an elongated loop which in operation revolves and insures rapidity and uniformity of action throughout the electrol- ysis. The cathodes are of platinum gauze of cylindricalshape. For other Electrodes see platinum ware, page 497. 8307. Platinum Anode, made of heavy wire with special elongated loop. Weight approximately 4.5 grams. Intended specially for use with No. 4786 Braun Electrolytic Outfit. At market price of platinum. 8308. Platinum Electrode, with closed gauze cylinder. Height 2 inches, diameter 1 inch, of 52-mesh gauze Approximate weight, 10 grams. At market price of platinum. 242 A RT HU. OR H. T HO M “A. Ss © 2.0 M P A NY ELECTROMOTIVE FORCE (For apparatus for the Colorimetric Method for the Determination of H-ion Concentrations, see page 163.) Apparatus for its measurement, with particular reference to the determination of H-ion concentration in solutions and for oxidation, concentration, polarization and contact potentials H-ION CONCENTRATION. Electrometric methods for the accurate determination of hydrogen-ion concentrations in solutions consist essentially of measuring a potential difference or electromotive force between two electrodes which form the extremities of a so-called gas chain. The term ‘‘gas chain” is used to designate systems similar to the one represented in the formula: Hg | Hg.Cl. | KCl | H+ | H»Pt, or in other words, the combination of the electrodes with the solution under test. Results of measurements made upon the gas chain with electrical instruments emphasize the meaning of actual or effective reaction of a solution as distinguished from total reaction. The measured electromotive forces correspond to actual hydrogen-ion content of the solution, and have only an indirect relation to the total acid or base present. In most cases actual reaction is the significant quantity. To determine it by titration with an indicator is in most cases impossible, for although this process would give the data needed to compute the total acid or alkali present at the beginning of the titration (7. e., the total reaction) it would give no clue to the per cent. of the total which was dissociated. The percentage dissociation, however, determines the actual reaction. The electrometric methods conveniently give not only the values of actual reactions, but with their aid it is possible to make titrations very precisely to any desired point, so that total reaction values are at once determinable. The advantages of the electrometric methods of measuring hydrogen-ion concentration may be briefly summarized as follows: 1. Color or turbidity of the solution, and conditions of illumination do not affect the accuracy of the measurement. 2. The entire range of concentrations—from normal acid to normal basic—is covered in one apparatus. 3. In many investigations greater precision in the values of hydrogen-ion concentration is necessary or desirable than is attainable with colorimetric methods. 4. No titrations are necessary in measurements of actual reaction. The methods give results which are determined by the actual hydrogen-ion concentration of the medium under investigation. 5. Should titration to any particular point of acidity or alkalinity be desirable, the electrometric methods give a reliable indication of any desired end point. 6. There is no method for studying the behavior of solutions as regards hydrogen-ion concentrations with changing conditions which gives so clear an insight into the meaning of acidity. 7. The electrometric method for determining hydrogen-ion concentrations is the primary and funda- mental method, since the data given in connection with colorimetric methods must be determined by an electro- metric method. Of the three general methods of measuring potential difference without passing a detrimental current through the source being measured, i.e., the quadrant electrometer method, the condenser method and the potentio- meter or compensation method, the potentiometer method is mostly preferred because of the greater accuracy obtainable without any great degree of manipulative skill. The method involving the use of the Type K Poten- tiometer has become the standard for precise work, yielding as it does an accuracy of from .02% to .04% (+ 0.2 millivolt). The Simplified Potentiometer with proper equipment yields an approximate accuracy of .05 to .2% (+ 0.5 millivolt), while the Hildebrand method operating on the potentiometer principle, but without the use of a potentiometer proper, yields from 1% to 2% (+ 10 millivolts). Within a comparatively few years, upwards of a thousand papers have been published upon one or another aspect of H-ion concentrations. The Leeds & Northrup Company have published. in “Electrometric Methods and Apparatus for Determining Hydrogen-ion Concentrations,” an elaborate discussion of recent methods and the necessary equipment therefor, with a selected bibliography from the recent literature, which we here reproduce by permission: BalLey, C. H.—A simple hydrogen electrode, J. Biol. Chem., 42, 45, 1920. Baker, J. C., and VAN SLYKE, L. L.—A method for making electrometric titrations of solutions containing protein, Jour. Biol. Chem., 35, 137, Bserrum, N.—Ueber die Elimination des Diffusionspotentials zwischen zwei verdiinnten wasserigen Lésungen durch Hinschalten einer kon- zentrierten Chlorkaliumldésung. JZ. physik. Chem., 53, 429, 1905. BserruUM, N.—Die Theorie der alkalimetrischen und azidimetrischen Titrierungen, Stuttgart, 1914. Bovig, W. T.—A direct reading potentiometer for measuring and recording both the actual and the total reaction of solutions. J. Med. Res., 33, 295, 1915. BuNKER, J. W. M.—The determination of hydrogen-ion concentration. J. Biol. Chem., 41, 11, 1920. CuarK, W. M.—The “‘reaction” of bacteriologic culture media. J. Infect. Dis., 17, 109, 1915. CLaRK, W. M.—A hydrogen electrode vessel, J. Biol. Chem., 23, 475, 1915. CLaRK, W. M.—The Determination of Hydrogen Ions. Baltimore, 1920. CLEVENGER, C. B.—Hydrogen-ion concentration of plant juices. I. The accurate determination of the hydrogen-ion concentration of plant juices by means of the hydrogen electrode. Soil Science, 8, 217, 1919. CumMING, A. C., and ABEGG, R.—Zur Eliminierung der Flissigkeitspotentiale. Z. Elektrochem. 13,17, 1907. Cummine, A. C., and GILCHRIST, E.—On the potential due to liquid contact. Ill. Trans. Faraday Soc., 9,174, 1913. Eis, J. H.—The free energy of hydrochloric acid in aqueous solution. J. Am. Chem. Soc., 38, 737, 1916. Fass, H. A. and NELSON, J. M.—The effect of sodium chloride upon the action of invertase. Jour. Am. Chem. Soc., 37, 2769, 1915. Faues, H. A. and Vospurcu, W. C.—Planck’s formula for the potential difference between solutions and the values of certain important cells. Jour. Am. Chem. Soc., 40,1291, 1918. GILLESPIE, L. J.—The reaction of soil and measurements of hydrogen-ion concentration. J. Wash. Acad., 6, 7, 1916. Haas, A. R. C.—Studies on the reaction of plant juices. Soil Science, 9, 341, 1920. HARNED, H. S.—The hydrogen and hydroxyl ion activities of solutions of hydrochloric acid, sodium and potassium hydroxides in the presence of neutral salts. J. Am. Chem. Soc., 37, 2460, 1915. HASSELBALCH, K. A.—Verbesserte Methodik bei der elektrometrischen Reaktionsbestimmung biologischer Flissigkeiten. Biochem. Z., 49, 451, 1913. inter) : . ; HASSELBALCH, K. A.—Methods for the electrometric determination of the concentration of hydrogen ions in biological fluids, Biochem. Bull., 2, 367, 1912. HasseELBALcu, K. A., and LUNDSGAARD, C.—Elektrometrische Reaktionsbestimmung des Blutes bei Kérpertemperatur. Biochem. Z., 83, 77,1912. Hinwumeson, L. J.—Das Gleichgewicht zwischen Basen und Sauren im tierischen Organismus. Ergeb. Physiol., 8, 254, 1909. HILpEBRAND, J. H.—Some applications of the hydrogen electrode in analysis, research and teaching. J. Am. Chem. Soc., 35, 847, 1913. 243 AS Re EU eR: H. T H O M A SS C O M P A N Y HILDEBRAND, J. H.,and Bowers, W. G.—A study of the action of alkali on certain zinc salts by means of the hydrogen electrode. Jour. Am. Chem. Soc., 38, 785, 1916. HOAGLAND, D. R., and Suarp, L. T.—Relation of carbon dioxide to soil reaction as measured by the hydrogen electrode. Jour. Agr. Res., 12, 139, 1918. Hoser, R.—Ueber die Hydroxylionen des Blutes, II. Arch. f. d. ges. Physiol. (Pfluger’s), 99, 572, 1093. Jones, H. M.—A rapid hydrogen electrode method for determination of hydrogen-ion concentrations in bacterial cultures or in other turbid or colored solutions. Jour. Infect. Dis., 25, 262, 1919. KLopstsG, P. E.—A simple method for titrating electrometrically to a desired end point in acid-alkaline reactions. Science, 52, 18, 1920. Konikorr, A. P.—Ueber die Bestimmung der wahren Blutreaktion mittels der elektrischen Methode, Biochem. Z., 51, 200, 1913. Lewis, G. N., BRIGHTON, T. B., and SEBASTIAN, R. L.—A study of hydrogen and calomel electrodes. Jour. Am. Chem. Soc., 39, 2245, 1917. Loomis, N. E~—Notes upon the potentials of calomel and hydrogen electrodes. Jour. Phys. Chem., 19, 660, 1915. Loomis, N. E., and AcREE, S. F.—A study of the hydrogen electrode, of the calomel electrode and of contact potential. Am. Chem. J., 46, 585, 1911. MCCLENDON, J. F.—New hydrogen electrodes and rapid methods of determining hydrogen-ion concentrations. Am. J. Physiol., 38, 180, 1915. MCCLENDON, J. F.—The Physical Chemistry of Vital Phenomena. Princeton, 1917. MCCLENDON, J. F.—Improved gas chain methods of determining hydrogen-ion concentration blood. Jour. Biol. Chem., 24, 519, 1916. MCCLENDON, J. F.—A direct reading potentiometer for measuring hydrogen-ion concentrations. Am. Jour. Physiol., 38, 186, 1915. MICHAELIS, L.—Die Wasserstoffionenkonzentration, Berlin, 1914. MIcHAELIs, L., and Daviporr, W.—Methodisches und Sachliches zur elektrometrischen Bestimmung der Blutalkalescenz. Biochem. Z., 46, 131, 1912. Miroy, T. H.—Changes in the hydrogen-ion concentration of the blood produced by pulmonary ventilation. Quart. J. Exp. Physiol., 8; 141, 1915. OstWaLp, W.—Ueber die absoluten Potentiale der Metalle nebst Bemerkungen tiber Normalelektroden. Z. physik. Chem., 35, 333, 1900. PLANCK, M.—Ueber die Potentialdifferenz zwischen zwei verdiinnten Lisungen binirer Electrolyte. Ann. Physik. Chem., 40, 561, 1890. PLuMMER, J. K.—Studies in soil reaction as indicated by the hydrogen electrode. Jour. Agr. Res., 12, 19, 1918. SCHMIDT, CarL L. A., and HoaGLanp, D. R.—Table of pH, H and OH_ values corresponding to electromotive forces determined in hydrogen electrode measurements, with a bibliography. Univ. of Cal. Pub. in Physiol., 5, 23, 1919. SHarp, L. T., and HOAGLAND, D. R.—Acidity and absorption in soils as measured by the hydrogen electrode. Jour. Agr. Res., 7, 123, 1916. NE me P. L.—Ueber die Messung und Bedeutung der Wasserstoffionenkonzentration bei biologischen Prozessen. Ergeb. Physiol., 12 393, 1912. Tacug, E. L.—A study of the determination of amino acids by means of the hydrogen electrode. Jour. Am. Chem. Soc., 42,173, 1920. WALPOLE, G. S.—Gas electrode for general use. Biochem. J., 7, 410, 1913. WALPOLE, G. S.—An improved hydrogen electrode. Biochem. J., 8, 131, 1914. WaLpo_e, G. S.—Hydrogen potentials of mixtures of acetic acid and sodium acetate. Jour. Chem. Soc., London, 105, 2501, 1914. WItsmorE, N. T. M. and OstwaLp, W.—Ueber Elektrodenpotentiale und absolute Potentiale. Zeitschr. f. phys. Chem., 36, 91, 1901. POTENTIOMETER, Leeds & Northrup Type K. Thisisa direct reading instrument with three direct ranges of 0.16, 1.6 and 16 volts. On the 1.6-volt range the smallest division of the slide wire scale represents 3; milli- volt and fifths of these divisions can easily be estimated. It is without contact resistances in the potentiometer circuit proper, has low internal resistance and is provided with a quick method of applying the standard cell. With conditions of maximum sensitivity and a suitable galvanometer, such as No. 4796, approximate accuracy in the measurement of electromotive force from .02 to .04% (+ .02 millivolt) is obtainable. With the advent of the electrometric method for the measurement of hydrogen-ion concentrations, it has come to be unquestion- ably the standard instrument for all chemical and biological laboratory work. R 4790—Diagram showing electrical connections of Type K Potentiometer The essential part of the instrument consists of 15 five-ohm coils AD of above diagram adjusted to equal- ity to a high degree of accuracy, connected in series and having in series with them an extended wire DB, the resistance of which from 0 to 1000 on its scale (the entire scale reading from 0 to 1100), is also five ohms. A contact point M is arranged so that it can make contact between any two of the five-ohm coils and a contact point M! so that it can make contact at any point on the extended wire DB. Current from the battery W flows through these resistances and by means of the regulating rheostat R it is so adjusted as to be exactly one-fiftieth of an ampere. The fall of potential across any one of the coils AD is consequently one-tenth of a volt and that across the extended wire DB is .11 volt. By placing the contact point M! at zero and by moving the contact M, the fall of potential between M and M! may be varied by steps of one-tenth of a volt, from 0 up to 1.5 volts. The wire DB is divided into 1100 equal parts. By moving the contact point M! from 0 to 1100, the fall of potential between M and M! may be varied by infinitely small fractions of a volt. To make use of this variable fall of potential in making measurements, an unknown electromotive force is introduced in series with a galvanometer between the points M and M' and in opposition to the fall of potential along AB. The contact points M and M? are then adjusted until the galvanometer shows that no current is flowing, when the value of the unknown electro- motive force can be read from the position of the points M and M!. In the diagram, the connections show the unknown electromotive force introduced at the binding posts marked E. M. F., the galvanometer at the point 244 A R T H U_R H. T H O M A SS CO: M —P A NY Ga, and in series with these, three keys marked R,, R2and Ry. When the key R, is depressed the circuit is closed through a high resistance; when key Rz is closed the circuit is closed through a lower resistance, and when key R, is closed the circuit is closed through zero resistance. The purpose of keys R, and R» is to protect the galva- nometer against excessive deflections when the opposing electromotive forces are not approximately balanced. No. 4796 Enclosed Lamp and Scale Galvanometer with a resistance of approximately 1000 ohms has been especially designed for hydrogen-ion concentrations in connection with the Type K Potentiometer. This type galvanometer has almost entirely replaced the use of a capillary electrometer as the detector in potentiometer arrangements, not only because this form of galvanometer is more sensitive, but also because it avoids the differ- ences due to polarization which occur in the capillary electrometer. 4790. ESEnu en Aes L. & N. Type K, as above described, with mahogany cover and diagram of connec- LOTUS os cere cei ceuavet gh awieiee weg ereuean Sesaley ha tua aad 3 es ee tet Smale lala dan eas th atanel hme be es hime dh eeekn dau oe 275.00 id « >) aS Reta 4792 Diagram showing electrical connections of Simplified Potentiometer POTENTIOMETER, Leeds & Northrup Simplified, while following the fundamental design of the Type K Potentiometer, is not entirely a self-contained instrument. The educational feature of the simple slide wire, set up so that the student must make his own connections between the component parts, has been retained. There are 22 resistance coils with a resistance of 100 ohms each, with a slide wire of a total resistance of 100 ohms. The terminals of this 2300-ohm subdivided resistance are brought out to a pair of binding posts. A second pair of binding posts leads to the twosliding contacts. The connections are shown in above diagram. The resistance coils are adjusted to be like one another to an accuracy of 1/25 per cent. The calibration of the slide wire is within 3 per cent. of its range. The range of the slide wire is 0.1 volt, so that measurements may be made to .0005 volt. In measuring 0.1 volt, therefore, there may be an error of } per cent.; in measuring 0.2 volt there may be an error of } per cent. Any voltage up to 2.3 volts—the limit of the instrument—may be measured to + 0.5 millivolt. For many purposes this accuracy, depending upon the resistance of the solution containing the Hydrogen Elec- trode, will be sufficient inasmuch as one millivolt in change of potential in the Hydrogen Electrode corresponds approximately to 1/60 of a pH unit. , \ . Extension coils and cut-out switch provided in the improved form (as in the Simplified Kohlrausch Slide Wire Bridge) render this instrument available for conductivity measurements in addition to potential measure- ments. Where potential measurements only are to be undertaken, the Simplified Potentiometer without these accessories is furnished at a lower price. For potential measurements, a resistance of about 1000 ohms, variable in small steps, such as Sliding Contact Tube Rheostat No. 8714, is required for adjustment of the working current. If the instrument is to be used both as a Kohlrausch Bridge and as a Potentimoeter, Four-dial Resistance Box No. 3967 is recommended for adjustment of the working current, in which case it is unnecessary to order the Sliding Contact Tube Rheostat. The Portable d’Arsonval Galvanometer No. 4800 is recommended for use with these Potentiometers 4792. Potentiometer, L. & N. Simplified, with extension coils and cut-out switch, as above described; for use both as a Potentiometer and as a Kohlrausch Slide Wire Bridge. .... Bets ecoaarih 4 teen oun omen 90.00 4793. ditto, but without extension coils and cut-out switch, for use as a Potentiometer only....... 80.00 8714. Sliding Contact Tube Rheostat, 920 ohms, 0.6 amperes working capacity..................... 8.00 3967. Resistance Box, L. & N., four dial, for use in adjustment of the working current in potential measure- ments or with above Potentiometer when used as a Kohlrausch Slide Wire Bridge...... 55.00 245 A R T H U_ R H. T H O M A 5S Cc O M P A N _ Y oye 4804 4808 ENCLOSED LAMP AND SCALE GALVANOMETER, Leeds & Northrup, designed especially for use in the measurement of hydrogen-ion concentrations in connection with the Type K Potentiometer. It requires no leveling and can be used under conditions which would make the use of a more delicate instrument impossible. A small incandescent lamp with straight filament is enclosed in the case with the galvanometer, and an image of this filament is projected from the galvanometer mirror on the scale mounted in the front of the case. The 4-volt lamp can be used on 110 or 220-volt circuits with the use of a lamp resistance listed with the galvanometer. The coil has a resistance of approximately 1000 ohms, with a period of three seconds and a sensitivity of 40 to 50 milli- meters per microampere. The use of a high resistance galvanometer makes for greater sensitivity because the galvanometer resist- ance becomes comparable with that of the remainder of the circuit. Furthermore, smaller current is taken from the hydrogen-calomel cell when the potentiometer is unbalanced and the key is tapped than is the case with a low resistance instrument. Thus disturbance of the electrode potential is avoided. It should be noted that so long as the potentiometer is appreciably out of balance it is desirable that the galvanometer key be pressed down for short periods only. While the hydrogen electrode is considered reversible, possible changes in equilibrium may thus be avoided. The best method is to give the key a quick tap. The direction of the deflection may then be observed, the sliding contacts moved and the galvanometer key is again tapped; this process is continued until a balance is obtained. A rough balance is obtained with a large resistance in series with the galvanometer by the use of key R, on the potentiometer. Key R; removes part of this resistance and key R, gives the maximum sensitivity. It is rarely necessary to use Ry, since Rz gives sufficient sensitivity for practically all measurements. 4796. Galvanometer, L. & N. Enclosed Lamp and Seale, as above described and as specially designed for H-ion concentrations in connection with Type K Potentiometer..................0.... 00-20 55.00 4797. Lamp Resistance, required when using Enclosed Lamp and Scale Galvanometer on 110-volt circuits. 5.00 4798. ditto but tor22 0=Volt: cincults Wi. iva cae ntcm ie uan elt aora me nes oatlpeenne etter nay, Com Re a 5.00 4799. Incandescent Lamp, only, 4-volt, for use with Enclosed Lamp and Scale Galvanometer.......... 1.00 d’ARSONVAL GALVANOMETER, Leeds & Northrup Portable. This galvanometer was also specially designed for use as an indicating instrument in gas chains and other high-resistance circuits as in hydrogen-ion concentrations. While not equalling the Enclosed Lamp and Scale type in sensitivity, and, therefore, not recom- mended for use in combination with the Type K Potentiometer, it is recommended for use with the Simplified Potentiometer and with such assemblies as No. 4886 for the Hildebrand method. The instrument is neatly mounted in a compact Bakelite case and has a resistance of 1000 ohms, three second period, and a sensitivity of 2 millimeters per microampere. 4800. Portable d’Arsonval Galvanometer, L. & N., as above described.............----200-- 2200-005 18.00 CAPILLARY ELECTROMETER, Eppley. For those who prefer to use the Capillary Electrometer as an indicator in the measurement of e.m.f.by the potentiometer method, we offer this new form. Contents of the electrometer tube are sealed in an exhausted tube, making impossible any loss of sensitivity due to soiling of capillary by the entry of outside impurities. The reading microscope is furnished with adjustable micrometer scale in the eyepiece, which permits exact setting against the top of the mercury column. Each instrument is tested for maximum workable sensitivity before shipment. 4804. Capillary Electrometer, Eppley, as above described and illustrated............-- cc ccecceeceee 80.00 4805. Capillary Electrometer, Glass Part, only, for replacement of RCA ARE: <8 oe wee wearers area aus eauee 12.00 4806. Reading Microscope, only, with 7.5 X micrometer ocular and 48 mm. objective, suitable for use with support No. 9436, but without support 4807. Capillary Electrometer Tube, Ostwald, vertical form, without contacts and unfilled............. 1.50 4808. Capillary Electrometer Tube, Luther, with contacts, but unfilled................ sors (ocese eens oiaKe 6.00 246 A R T H U_ R H. T H O M AS Cc -O MP A NY mM i TOMO TATSESOU TAAL _ STANDARD CELLS. These are of the unsaturated type for use in connection with any zero method for determining electromotive forces or potential differences, i. e., in connection with methods where no current is drawn from the cell when balance occurs. These are universally used with potentiometers for making measure- ments of current and voltages as in hydrogen-ion concentration determinations, and for calibration of electrical measuring instruments. Standard Cells should never be connected to a voltmeter to ascertain the e.m.f. of the cell, or accuracy of the voltmeter. 4820. Standard Cell, Weston Model 4, in moulded Bakelite case, with binding posts. With Weston certificate. 25.00 4821. ditto, but with Bureau of Standards certificate... 0.0.0.0. 0. cece cece eee ee eeeaes 29.50 4822. Standard Cell, Eppley, in moulded Bakelite case, with binding posts. With Eppley certificate.... 15.00 4823. ditto, but with Bureau of Standards certificate...... 0.0.0... cee cee ete cence 18.00 4826. Standard Cell for Students’ Use, Eppley. This cell is identical with the Eppley Standard Cell listed above, but shows e.m.f., differing somewhat widely from that accepted as standard from unsaturated cell. This is due to less rigorous control of the concentration of the cadmium solution than is maintained in the preparation of this solution for precision standards. The cell is hermetically sealed in glass, mounted on an open support with depolarizer protected against the action of light. It is correct EOP oss SMEOUN Ee eaeyens etider clit one tol ven atelier si een RA Galena aad iene ures momen aah waded 8.00 4827. ditto; -butsunmounteds. 2 rciacscatateaterssea gout sete ces dereast asa wietameiesaccun agerauca eee a arcu Since eres 7.00 4828. Standard Cell Vessel, usual H-form, unfilled and unmounted, but with platinum contacts fusedin.. 4.10 4829. ditto;, butsof- improved "designics. aave sacks sarnasseuseun sane nee ke seas Gates wena as eatin ds AM 5.30 PORTABLE HYDROGEN-ION POTENTIOMETER, Leeds & Northrup. The new unit is a potentio- meter, i. e., an instrument the accuracy of which depends upon the precision and constancy of a standard cell and of electrical resistances rather than a group of instruments operating on the compensation method. It has a range of 0 to 1.2 volts, an absolute accuracy of 4 millivolt, and a sensitivity that is ample for measurement in all ordinary solutions. The instrument has a main dial reading to 1.1 volts, in steps of .1 volt, and a uniform slide wire with a range of .1 volt. The galvanometer is of the high resistance type especially designed for gas chain work. The set contains a standard cell with reference to which the working current is adjusted. It requires two dry cells as a source of working current. Standard cell, galvanometer, adjusting rheostat—all are enclosed in a substantial oak case 6 inches by 6 inches by 93 inches, provided with a carrying strap. All parts are ruggedly constructed to withstand hard usage. This outfit will be found useful, not only in laboratory work, but for field and plant survey and elsewhere where convenient portability is a desirable feature. 4832. Portable Hydrogen-ion Potentiometer, L. & N., as above de- scribed, range 0 to 1200 millivolts, accuracy + 0.5 millivolt (1% of a pH unit), sensitivity ample in all solutions except 4832 those of extremely low conductance................150.00 247 Ay RT. SE UR: He T H O M AS CG “Oo “MP A. GN) Vy CALOMEL, HYDROGEN AND OTHER ELECTRODES It is customary to use a standard form of unvarying electrode, such as the mercury-calomel-KCl combina- tion as the reference electrode, as its constancy is more dependable and its electrode potential is more accurately known than that of a hydrogen electrode in a standard buffer mixture. While calomel electrodes in which the KCl solution may be 75 normal, normal, or saturated, have been widely used, many recent workers prefer the saturated KCl calomel cell to the others for the reasons given by Fales and Mudge, Journal of the American Chemical Society, December, 1920, and others, which show that very small changes in concentration are sufficient to change the potential of the ~; normal and normal electrode by a large amount. If a saturated KCl calomel cell is used, there will be no tendency for the solution in the vessel and the connecting vessel to interdiffuse, since they are at the same concentration. The saturated calomel electrode is also less sensitive to electrode potential change at higher temperatures, and because of its conductivity increases the sensitivity of the apparatus used in gas chain measurements. Many forms of Hydrogen Electrodes are now described in the literature, but for general work in inorganic solutions, as well as in some organic solutions, particularly when the latter do not contain proteins, the Hydrogen Electrode of Hildebrand has been found very satisfactory. The shaking form of electrode as described by Clark is widely used for a great variety of work in bio-chemistry, particularly in the determination of the true reaction of culture media. For blood and serum and other physiological and clinical work, the two-part electrode of Mc- Clendon has been found very satisfactory. In the preparation of a Hydrogen Electrode for use, the metallic electrode must be platinized by electrolytic deposition, using a platinum electrode in a 3% solution of platinic chloride containing ~;% of lead acetate. Occasional reversals of current are advisable in this process. The platinum black may be desposited on a platinum or gold electrode, and by some workers gold is considered preferable to platinum because of its relatively smaller occlusion of hydrogen, which presumably allows the electrode to come into equilibrium more rapidly. It is usually more convenient, however, to use the hydrogen commercially obtainable in pressure cylinders, which contain a sufficient amount for a large number of determinations.* For purification, the hydrogen should be passed through an alkaline solution of pyrogallic acid, and where measurements of great precision are contemplated, through a solution similar to the one upon which the measurement is being made. Fig. 1. A typical gas chain cell. A typical form of gas chain cell with connecting vessel containing saturated KCl solution is shown in Fig. 1. The connecting vessel of saturated KCl, or salt bridge, as suggested by Bjerrum, reduces, as mentioned in the preceding text, the potential differences because of the contact of two solutions of different concentration to a very small amount. If the gas chain is used in measuring relative values and changes in concentrations only, the connecting vessel may be omitted. When this practice is fol- lowed, the calomel electrode should be frequently flushed out with a potassium chloride solution of appropriate concentration in order to avoid changes in its electrode potential. A gas chain cell widely used is shown in Fig. 2, which con- sists of No. 4854 Clark Hydrogen Electrode for shaking, No. 4866 Clark Connecting Vessel, and No. 4834 Calomel Electrode Vessel, shown in the diagram in their relative positions for use. To convert the measured values of the electromotive force of the gas chain to corresponding values of H-ion concentration, or pH, it has been customary to use a conversion table of the kind given by Schmidt and Hoagland, University of California Publications in Physiology, 5:23, 1919. A still more convenient device now available is the Hydro- gen-ion Calculator, devised by the Leeds & Northrup Company, which operates on the principle of the slide rule, and with which 4880 these conversions can be rapidly made, regardless of the potential Hydrogen-ion Calculator. of the reference electrode. * The hydrogen as manufactured by the Linde Air Products Company has been found satisfactory. 248 or any. Re 4834 4836 4838 8¢ 4841 4834. Calomel Electrode Vessel, with fused-in Platinum wire and stopcock. A convenient and satisfactory form for a great variety of work. As shown in connection with the Clark Hydrogen Electrode No. 4854, page 248. With Platinum contact in the form of a flat spiral........ Brier repeat 4.00 4836. Calomel Electrode, with constriction near bottom which prevents the disturbance of the mercury when the cell is tilted, rendering it easy to remove the KCl solution due to diffusion in order to keep the voltage of the calomel electrode constant..... 0.6.66... eee 8.10 4838. Calomel Electrode Vessel, as designed especially for use in the Kelley Electrometric Titration Apparatus No. 4920. Without metallic electrode... ..........00 00.0 8.00 4839. Platinum Electrode, for use with Kelley Calomel Electrode Vessel............... 0.222220 2005. 2.00 4840. Calomel Electrode Vessel, Pauli, with a stopcock in filling tubulation, ground in Platinum electrode and with short syphon tube. Designed for use with liquids of high resistance............ 11.00 4841. Calomel Electrode Vessel, Roberts, improved form, as used in the Hostetter and Roberts Titration Head No. 4911. The bottom of the capillary is furnished straight for bending in the laboratory after insertion through the glass sleeve of the Titration Head and for suitable adjustment to the height of the flask in use. See Journal of the American Chemical Society, XLI:1340,1919.. 3.00 4848 4850 4842 4844 Calomel Electrode Vessel, Sand, with fused-in Platinum connection and binding post at bottom. See Transactions of the Chemical Society 879; 19085. 5.5 sdina ds-oe a pacer R eee Ea ae et 9.25 N. A simplified form in which the short length of connecting tube makes for minimum resistance in this part of the gas chain, with correspondingly higher sensitivity than in the usual form of vessel. The position of the reservoir immediately above the connecting tube results in a shape easy to mount HI ATLY™ POSIUION: 2. nave cc ih weve ese ee ENN Bee ee fot pea aoe ee 4.50 : Electrode Vessel, a modified Hildebrand electrode with tube providing mercury contact with ore a ican wire. With fused-in Platinum wire..............-.. 6. see eee eee eens 5.00 4842. 4844, Calomel Electrode Vessel, L. & ’ lectrode Vessel, a modified Ostwald electrode. with glass tube providing mercury contact isa ee the Platinum wire. With fused-in Platinum Wile. 346 fvckessusemcer sees aes ten ase 5.40 ‘ de Vessel, 2 comparison group of three with junction. The calomel electrodes proper SR dee with glass tube for mercury contact with the fused-in Platinum wire..... 11.40 249 4850. AroUR: a ee aR H. T H O M A _ S CO Me PS Ay Nv Coy. AMT co 4854 4855 4858 4852. Hydrogen Electrode, Hildebrand, with S-shaped Platinum electrode and arranged so that half its surface is immersed while the other half is exposed to the gas. A convenient form for a great variety of work. See Journal of American Chemical Society, 35 : 847, 1913. With Platinum electrode, but without-adapter as:shown in Wlustration: 6.3 gciss:ccase oops oa be a Sey Res EE GB Se 5.75 4853. Adapter, for use with Hildebrand Hydrogen Electrode No. 4852 when used with the Kelley Electro- metric Titration Outfit arranged for hydrogen-ion concentration measurement............. 75 4854. Hydrogen Electrode Vessel, Clark; a widely used form of the shaking type of electrode, particularly designed for use in bacteriological and other biological determinations of hydrogen-ion concen- tration. See Journal of Biological Chemistry 23 : 475, 1915. Without metallic electrode... 9.00 4855. Platinum Electrode, for use with Clark Hydrogen Electrode Vessel, consisting of Platinum foil 6 mm square sealed in a glass tube 40 mm long with Platinum wire............................ 4.50 4858. Hydrogen Electrode, McClendon, a two-compartment modification of Hasselbalch’s electrode, arranged to eliminate the loss of CO. during transfer of solution. Specially designed for physiological and clinical work such as the determination of hydrogen-ion concentration of blood and serum. See Journal of Biological Chemistry, 25 : 669, 1916. Complete with gold electrode and Platinum WARE COMME CULOINY sez treas ined ah crt nash acts h aprons ee Aarne eee neice Poh at ipa ar acinn Sere here tart at Meee 12.00 4867 4860. Hydrogen Electrode, Bunker, a modification of the bubbling electrode, designed to meet the require- ments of rapid and accurate determinations in great numbers. The bubbling feature renders the shaking or rocking of the electrode unnecessary during measurement. See Journal of Bio- logical Chemistry, 41 : 11, 1920. Complete with Platinum electrode, stopcock and rubber Male GIS <3 seks ier ren sth ens Geach at ee re haa ea dennag ly a duah a wine GaSe 4.85 4862. Hydrogen Electrode, Bailey, a simple and convenient form designed for the determination of hydro- gen-ion concentration of the water extracts of plant material such as wheat flour, etc. See Journal of the American Chemical Society, 42 : 45,1920. Complete with gold electrode and Pla- GATIUIIMIL WAT Cr COMM CELT OMSE tee mens kere deh ae e aan teh cd bn car esl LN alte et fate Rey Nal ee tah SL MEME AN SAE elt 3.75 4864. Hydrogen Electrode Vessel, an improved Ostwald form with a stopcock at top of syphon tube. With- outePla tinum ele ctrod Gin cele cus kei te a i nS A ey Ah Gk Se esa ciel a Ababcni a ae ade ania = Gusto BS 6.25 4865. Platinum Electrode, for use with No. 4864 Hydrogen Electrode Vessel, consisting of Platinum foil 6 ae square sealed in glass tube 110 mm long with Platinum wire....................00-.00 00 4.00 4866. Connecting Vessel, Clark, for establishing liquid junction.................0 000.0 cece cece eeee 7.80 4867. Connecting Vessel, for establishing liquid junction. .......0.00 0000000 c ccc cece cece tne neeee 5.10 250 A R T H U_R H. T H O M AS Cc O M P A N _ Y 4868 4871 4873 4876 4868. Electrode Vessel, on glass foot; a convenient form for general work. Without Platinum electrode... 3.50 4869. Electrode Vessel, same as No. 4868, but without glass foot. Without Platinum electrode......... 1.50 4870. Metallic Electrode, consisting of Platinum foil 6 mm square, fused in glass tube 175 mm long with Platinum wire. Suitable for use in either No. 4868 or No. 4869 Electrode Vessel.......... 4.00 4871. Electrode Vessel, for use either as a metallic or a calomel electrode, without metallic electrode..... 4.10 4872. Metallic Electrode, consisting of Platinum foil 6 mm square, fused in glass tube 140 mm long with Platinum wire. Suitable for use in No. 4871 Electrode Vessel...................0.00005: 4.00 4873. Electrode Vessel, for use either as a metallic or a calomel electrode, without metallic electrode.... . 6.75 4874. Metallic Electrode, consisting of Platinum foil 6 mm square, fused in glass tube 190 mm long with Platinum wire. Suitable for use in No. 4873 Electrode Vessel.................. 20000005: 4.00 Note—As metallic electrodes for use in both gas and metallic electrode vessels are used in some variety of form, it is recom- mended that those other than listed be prepared in the laboratory. 4876. Glass Tube, of Pyrex glass, for salt bridge, bent in convenient form for immediate use............ 15 A.W. T. Ce 4878 ; 4880 Combined Support and Shaker, Leeds & Northrup, for the calomel electrode, connecting vessel and hydro- gen electrode, consists of a heavy iron tripod with convenient rigid support with binding posts for the calomel electrode and liquid junction vessel, with a suitable shaking device driven by electric motor for the hydrogen electrode. Illustration shows two No. 4854 Clark Hydrogen Electrodes, No. 4834 Clark Calomel Electrode, and No. 4866 Liquid Junction Vessel in position, but these are not included in the price. 4878. Combined Support and Shaker, L. & N., as above described; with motor for 110-volt, 60-cycle a.c.... 75.00 4879. ditto, but with motor for 110-volt d.c..... 0.0.66 cece ene ees 75.00 4880. Hydrogen-ion Calculator, L. & N. A specially devised slide rule, by means of which voltage readings at 25° C between a calomel electrode and a hydrogen electrode are easily converted into the cor- responding pH or Ch+ value of the solution under test. It is based on the relation V=v+.0591 pH, in which V is the observed voltage, and v the potential difference between the calomel cell used in the measurement and a hydrogen electrode in a normal solution of H+. The values of v for saturated, normal and tenth-normal electrodes are marked on the voltage scale. The cal- culator is correct for a temperature of 25° C. It is neatly made of celluloid, with directions for oper- ation printed thereon, and on the back of the calculator are tables giving the corresponding values of pH and CH + for any pH interval, by means of which more exact values of CH-+ can be obtained than on the H-ion scale of the calculator; and also a table of approximate pH and CH-+ values of common solutions; and of the Clark & Lubs set of Indicators for the colorimetric determination of hydrogen-ion concentrations. ....... 0.6.6.6. beeen eee 50 As (Re Fi Eo Gs aR fo 30. Mo AS Cc O M PAN Y COMPLETE OUTFITS FOR VARIOUS POTENTIAL MEASUREMENTS a To LAMP RESISTANCE AND SOCKET. 4882 RT Pa Gu A Type K Potentiometer Outfit, with diagrammatic illustration of connections. TYPE K POTENTIOMETER OUTFIT. This equipment is suited for practically every hydrogen-ion research problem in bacteriology, physiology, and bio- chemistry, and has been arranged as a result of the expe- rience of many competent investigators in this field. It is particularly convenient as regards setting up and operation since no adjustments requiring high manipulative skill are necessary. In the few research problems requiring a still higher precision, it is only necessary to substitute a more sensitive type of galvanometer, such as the L. &N. Type R, with lamp and scale, angle mirror, wall bracket, and right angle prism, and a Constant Tem- perature Oven or Constant Temperature Oil Bath for the gas chain cell. With the Enclosed Lamp and Scale Galvanometer as above illustrated, the Type K Potentiometer Outfit measures the difference in potential between a calomel electrode and hydrogen electrode to from .02 to .049% (+ .2 millivolts), which in ordinary solutions is the equivalent of 0.0001 of the pH unit. The outfit consists of the following equipment: 4790. Type K Potentiometer, L. &. N. 4820. Weston Standard Cell, Model 4 4796. Enclosed Lamp and Scale Galvanometer, L. & N. 2092. Storage Battery 4797. Lamp Resistance for Galvanometer, for 110 4854. Clark Hydrogen Electrode Vessels with two volts platinum electrodes for same (2) 4878. Combined Support and Shaker, L. & N., for calo- 4834. Calomel Electrode Vessel mel electrode, connecting vessel and hydrogen 4866. Clark Connecting Vessel electrode, with motor for 110 volt, 60 cycle, a.c. 9374. Switch, single pole double throw 4882. Complete Outfit, as above listed, with Shaker with motor for 110 volts, 60 cycle, a.c............ 471.60 4883. ditto, but with Shaker with motor for 110 volt d.c.. 000. eee 471.60 HILDEBRAND HYDROGEN-ION OUTFIT (Listed and described on following page.) AM T.Co.PHILA. 4886 Hildebrand Hydrogen-ion Outfit, with diagrammatic illustration of connections. 252 A R T H U_ R H. T HO. M To CELL ) poe To LAMP RESISTANCE > AND SOCKET oO a aa Soe 4890 BOVIE POTENTIOMETER, Leeds & Northrup, originally described in Journal of Medical Research, 33; 295, 1915, by Dr. W. T. Bovie, assistant professor of biophysics, Harvard University, and designed and con- structed by Leeds & Northrup Company in the form shown in above illustration. This is a semi-automatic recording potentiometer by means of which H-ion concentrations are directly plotted as a function of some measurable, variable quantity, with which the H-ion concentration is changing. The variable quantity may, for example, be amount of titrating solution added or elapsed time. Records are made on a special cross-section paper by means of a marking device automatically moved along the H-ion scale as the potentiometer is balanced. This cross-section paper has millimeter divisions along the horizontal scale and four- teen sections of logarithmic divisions along the vertical scale, the latter reading H-ion concentrations directly. A reflecting galvanometer, especially designed for gas chain work is built into the case with the instrument, as is also the standard cell against which the working current is adjusted. The necessary tapping keys are mounted for convenient manipulation, and binding posts are provided for connection to circuit for operating the galvano- meter lamp, to the gas chain consisting of a saturated KCl calomel electrode and hydrogen electrode; and to the working current for the potentiometer, usually two dry cells. A rheostat for adjusting the working current is mounted in the instrument and a dial corrects the instrument reading for temperature changes in the gas chain. The galvanometer is sensitive to changes of 0.01 of a pH unit; its accuracy, depending somewhat on the gas chain resistance, is less, but on the same order of magnitude. The instrument measures and records both the actual (effective) and the total (titratable) reactions of solutions, and plots a curve of the changes of actual reaction as amounts of acids or bases are added to the solu- tion. The curves obtained show the changes in H-ion concentration of a solution with any other variable, such as time, growth of organisms, or the addition of acids or alkalies. The determinations can be made quickly and with much greater precision than with indicators. The results are free from the subjective errors of judgment of color- and are obtained in the form of a printed record of both the actual and the total reaction of the solution. More- over, the determinations can be made of the reactions of solutions which, because of their own natural color, make it impossible to use indicators, or of solutions which, because of their peculiar chemical constitution, make the indicator method unreliable. Determinations of the actual reaction and of the manner in which this reaction varies with different conditions are frequently of more value than are determinations of the total reaction. The total reaction, how- ever, is more frequently determined in biological work because of the time and labor required by the present methods of determining actual reactions. This instrument increases the ease of determining both the actual and the total reactions of solutions and also of determining the manner in which the actual reaction of solutions varies with varying conditions. This instrument is particularly adapted to research problems in which a record of the change in H-ion concentration is desirable as the charts (see typical illustrations on following pages) can be filed away with the observer’s experiments. In courses of physical chemistry, biochemistry, etc., this graphic method of emphasizing the true meaning of acidity and alkalinity and of the difference between actual reaction and total reaction seems particularly commendable. 4890. Potentiometer, Bovie, L. & N., as above described, with 25 sheets of semi-multiple logarithmic codrdinate paper and one spare lamp, diagram of connections and instructions for use; with resistance for 2 galvometer lamp for operation on 110-volt circuit... 2.0.0.0. o ooo cc ccc ccc cceceus 50.00 4891. ditto, but with resistance for 220-volt circuit.................................. ee eee 250.00 4797. Lamp Resistance, only, for 110-volt circuit..........................0000 0 5.00 4798. ss fs Bape od GO ee sh mga Pies eae, las Rigas hyena aa em rece ed Araneae Coan 5.00 4799. Incandescent Lamp, 4-volt, for Galvanometer...........................2-0 00 eee eee 1.00 4892. Semi-multiple Logarithmic Coordinate Paper, for use with Bovie Potentiometer, (see discussion at bottom of following page) with horizontal scale numbered 0 to 20 and with zero at left end. Per l0Oeh pe Greeer ane eto ee: 3.00 Per WOOO ks oeteics ee cele bless 25.00 4893. ditto, but with zero at middle of horizonal scale, numbered 0 to 10, left and right. Per hOO rece erin etl ee cia 3.00 Per 1000 254 A R T H U_R H. or Or pM AS Ss Cc O M P A N Y HYDROGEN-CALOMEL CELL, Bovie, as shown in illustration below, for the investigation of biological and other fluids available only in small quantities, consisting of a Hydrogen Electrode and Calomel Electrode inserted through a gas-tight glass lid to the extreme tip of a conical glass vessel, held in place against the rubber gasket of the lid by an opposing spring attached to an under clamp. In the center of the glass cover is an open- ing for the insertion of the burette tip. Lowering of the clamp with the spring permits convenient removal of the glass cone without interference with the set-up of apparatus and its connections. The tip of the Calomel Electrode is regularly supplied slightly turned up to prevent diffusion. Where very small quantities of solution are to be investigated, the author recommends that the tip of the Calomel Electrode be used straight rather than turned up, and of smaller diameter, which sometimes necessitates the use of a Quadrant Electrometer for measuring potential in place of the galvanometer as regularly supplied with most H-ion outfits, in order to avoid difficulties arising from closing the circuit through the galvanometer when the system is unbalanced. 4894. Hydrogen-Calomel Cell, Bovie, as above described and shown in illustration below, complete with special support, clamp, glass cone, calomel electrode vessel and hydrogen electrode vessel......... 33.00 4895. Hydrogen Electrode Vessel, Bovie, as used in above cell, with metallic electrode; as shown in A of illustrationibelows..cceves comets etree tare reel 6 Me An onteneenb ies Slbanysee Mecha iar lenitayiss soca maine» 4896. Calomel Electrode Vessel, Bovie, as used in above cell, consisting of B and C shown in illustration below. With metallic electrode but without mercury and calomel paste 00 4897. Glass Cone, only, as used in above cell 2.00 4898. Plate Glass Disc, for top of above cone. ... 1.0... eee tence teen eaee 1.00 4899. Support, only, consisting of tripod base, two clamps, the upper fitted with plate glass disc, glass cone with gas-tight cover, etc., as used in above cell 20.00 FOR BURETTE of THCMCMETER 4900 Bovie Hydrogen-ion Outfit, with diagrammatic illustration of connections BOVIE HYDROGEN-ION OUTFIT, complete, as shown in above illustration. This is a convenient arrangement as used by the author for the investigation of biological and other fluids available only in small quantities. The Bovie potentiometer is obviously equally adapted to all measurements of acidity and alkalinity with other hydrogen-calomel electrode combinations using a saturated KCl calomel cell. 4900. Hydrogen-ion Outfit, as above described, consisting of Bovie Potentiometer, Bovie Hydrogen-Calomel Cell with special support, and two dry cells. With resistance for galvanometer lamp for opera- tion on 110-volt circuit... eee tere ..... 283.00 4901. ditto, but with resistance for 220-volt circuit...... 0.6.6.6 6 6 eee eects 283.00 EXPLANATION OF LOGARITHMIC SCALE USED WITH BOVIE POTENTIOMETER This scale has a multiple logarithmic ruling of fourteen units. The numbers are the negative exponents of ten (the negative sign is omitted in the scale), hence the seale covers a range of hydrogen-ion concentrations from normal to 1 x 10-4 normal, i. e., from normal acid to normal base. If these numbers are read as positive numbers they correspond to the pH numbers of Sérensen. It is better, however, to read them as negative exponents of ten, since this avoids the introduction of a new system of units for indicating reaction. If read thus, the numbers decrease as the hydrogen-ion concentration decreases. ‘ ; ; The space between any two numbers is ruled logarithmically, like the rulings of the slide rule, so that the whole scale is as if fourteen slide rules were placed end to end. The values to be assigned to these logarithmic rulings will be understood from the diagram shown to the left. A few examples will make the method of reading clear. A reading at A is read 6 2x 10-5; at B, 6 x 10-°; and at C, 10x 10-° or 1 x 10-5; and at D, 4.5 x 10-. 5 It will be seen that the reading is to be associated each time with the negative expo- 15 1s nent of ten to the right of it. A somewhat awkward but easily understood method it { f 1 f | lf tf explaining the scale is as as follows: the logarithmic reading is the numerator, while | the number to the right of the reading indicates the number of zeros to be written c Ca) A after one in the denominator of a common fraction which represents the reaction Diagram Showing Logarithmic Rulings of the solution in the usual terms of normality, thus 3.4x 10~ equals normal. 1,000,000 : ae : . 34 : If we wish to avoid the decimal point in the numerator we may write 34 x 10-7 or 10.000.000 that is, the hydrogen-ion concentration is thirty-four times as great as that of distilled water. ; The ordinate ruling of this paper is like that of the scale described above. The abscissa ruling is linear, like that of ordinary cross- section paper, centimeter units divided into tenths. The ordinate units are negative, the abscissa units positive, and therefore the rulings lie in the lower right-hand quadrant of the system of coérdinates, and the origin is at the upper left-hand corner of the sheet. We are more ac- customed to plotting curves with both ordinate and abscissa values positive and at first this paper may seem bottom side up, but this difficulty disappears as soon as one has used the paper a few times. Placing the origin at the top has the advantage that a movement down the ordinate axis represents a decrease in the concentration of the hydrogen-ions. See The Journal of Medical Research, Vol. XX XIII, pp. 295-322, Nov.,1915. 255 AR eae ace YR H. THO. UM — ASS GeO INE SARA IN? Sy. SOME TYPICAL BOVIE POTENTIOMETER CURVES 2 Ot 6. Tl. Bh 9 c 1 2 we 5 e. 7 f 30) 3 32 3s. 2t 17 10-20. 22 43 AS 36 AG 32 3 me so Sy aE H eet eS EE pats oe a TTT ETT nt TT CH a f CE cn HT tt tt TREC Py HAA HA Fig. 1 Fig. 2 The titration of 10 ml of N/10 sulphuric acid with N/10 Curve A—The titration of a solution of phosphoric acid sodium hydroxide. Ordinates represent the hydrogen-ion con- with potassium hydroxide. centrations; abscissae represent milliliters of alkali added. Curve B—Titration of a saturated solution of boracic acid with sodium hydroxide. o 9 116 2 4 5 6 Fig. 3 Fig. 4 Curve A—Titration of a strong acid with a weak base. Curve No. 4—The addition of crystals of sodium acetate to (Hydrochloric acid with ammonia). 0.1 normal acetic acid. Ordinates represent the hydrogen-ion Curve B—Titration of a weak acid with a strong base. concentrations; abscissae represent the number of grams of Acetic acid with sodium hydroxide). sodium acetate added. Curve No. 5—The titration of a mixture of acetic acid and sodium acetate. To the right with N/10 normal hydrochloric acid; to the left with N/10 normal sodium hydroxide. The cuLve shows the buffer action of a sodium acetate-acetic acid solution. 256 n= URS ald ibane Uae SRR H. TE M A §S CG © iM (Pe “A. IN) SOME TYPICAL BOVIE POTENTIOMETER CURVES a z 1 0 4 > 6 7 9 Qo ’ 4 ef eke BE Ok 2 Fig. 5 Curve No. 6—To the right the addition of hydrochloric acid to distilled water; to the left the addition of sodium hydroxide to distilled water. Curve No. 7—The same as Curve No. 6, using culture media in the place of distilled water. The curve shows the buffer action of the culture media. oS: 0 2 Fig. 7 Acid dissociation curves. Ordinates represent the hydrogen- ion concentrations; abscissae represent the percent. of acetic acid in a dissociated condition. A graphical solution of the equations used in making isohydric solutions. Fig. Curve A—To the right the Cie of N/10 normal hydro- chlorie acid to distilled water. To the left the addition of N/100 normal sodium hydroxide to distilled water. Curve B—The same as A, using bog-water in the place of distilled water. The curve shows the buffer action of bog- water. i ti ar Lea iota TOULLEUE INT i UV im Lt 0 nN If i] fy Hel CE ean HE a tl i i a ce oe | ee i 7 p ae PH cE ae Ce VF cn ES Vest “ ae Be SPT i Tt i cee tale 2 aa = SS ae ee Ht oe ee 1 ceo = a regee hae Fig. 8 The dissociation-residue curve of an amphoteric electrolyte. The ordinates represent the hydrogen-ion concentrations; the abscissae represent the percent. of the electrolyte in the undis- sociated condition. 257 To LAMP RESISTANOE 4906 Titration Outfit for Comparison with Standard Buffer Mixtures, with diagrammatic illustration of connections TITRATION OUTFIT FOR COMPARISON WITH STANDARD BUFFER MIXTURES. A gas chain consisting of two hydrogen electrodes and a salt bridge affords a means of making titrations to a particular pH value without the use of a potentiometer. Our illustration shows a selection of stock apparatus for this purpose. If a titration is to be made to some particular value, say pH=8, select from the formulae of standard buffer mixtures one which has this value, and put the solution into a vessel as shown to the left in above illustra- tion. A hydrogen electrode is immersed in this solution. By means of a salt bridge establish contact with the solution to be titrated, which is placed in beaker at extreme right, which contains a second hydrogen electrode. The arms of the salt bridge are provided with suitable plugs of cotton wool to prevent siphon action. The hy- drogen electrodes are then connected as shown, into a circuit containing a galvanometer, switch and tapping key across which a 10,000-ohm coil is connected. The titrating solution is now added to the solution in right hand beaker, and the switch cautiously tapped so that the deflection of the galvanometer may be noted. When switch is closed, the 10,000-ohm resistance is in series with the galvanometer. Its purpose is to protect the gal- vanometer from too violent deflections, and at the same time to prevent polarization at the hydrogen electrodes. The titration is continued until upon tapping the key, the galvanometer deflection remains small. Then the key is used and the titration completed, which is indicated by zero deflection of the galvanometer. When this condition obtains, the inference is that the two electrodes are at exactly the same potential, which in turn means that the pH value of solution in right hand beaker must now be the same as that of solu- tion in beaker at left. To verify the correctness of the assumption, take either of the two hydrogen electrodes and place it in the same beaker with the other, and note whether the deflection remains zero. The accuracy of the pH value attainable in this manner is entirely a matter of how accurately the pH value of the standard buffer mixture is known. It is seen that this method has many of the advantages of the potentiometer method over the colorimetric methods, since it eliminates all subjective errors which are encount- ered in color titrations, and since it also does away with difficulty due to turbidity or color in the solution or con- ditions of illumination. Another advantage lies in the fact that no experience, aside from a short period of prac- tice, is needed to make an accurate titration in this manner. It is at once evident that in cases where it is of interest to adjust one solution to be exactly the same as another, regardless of the pH value, this method should prove very satisfactory. In this case the solution having the desirable properties is put in place of the standard buffer mixture. It should be emphasized that the method described is suitable only for making titrations to a particular end point, and is not suitable for measurements of pH values. Where such measurements are necessary, a potentiometer must be used. Where liquids, such as blood, sera, and other body fluids available in very small quantities only are to be investigated, a convenient arrangement similar to above is to be had by the substitution of two hydrogen electrodes of the Bunker type in place of those of the Hildebrand type as illustrated above. The outfit consists of the following equipment: 4796. Enclosed Lamp and Scale Galvanometer, L. & N. 9336. Support, large 4797. Lamp Resistance for 110 volts 3222. Clamps (3) 4799. Incandescent Lamp, 4-volt 4852. Hildebrand Hydrogen Electrodes (2) 4044. Single Contact Key 9356. Support, with clamp and connections 8741. Coil, 10,000 ohms, mounted 2128. Pyrex Beakers, 600 ml 9373. Single Pole Single Throw Switch 2128. “ ee 400 “* (2) 2410. Paired Burettes, 50 ml in 1/10ths, for titrating 4876. Bent Glass Tubes for the salt bridge (2) 4906. Complete Equipment, as above listed, with Galvanometer lamp resistance for 110-volt circuit... . 116.65 4907. ditto, but with lamp resistance for 220-volt circuit... 0.000. c cece eee 116.65 ROBERTS ELECTROMETRIC TITRATION UNIT, Leeds & Northrup, as originally designed for de- termining small amounts of ferrous oxide in the presence of much ferric oxide in the study of the oxides of iron at the Geophysical Laboratory (see Hostetter and Roberts, Journal of the American Chemical Society, XLI: 1337, 1919) but applicable to a wide range of electrometric titrations where the relative rather than the absolute values of the electromotive force developed during the titration are of significance. While in this method the change of voltage at the end-point is so great under appropriate conditions that the unit can be nearly balanced at the beginning of the titration and the end-point located by the large perma- nent galvanometer deflection that accompanies this change, the end-point of the titration, in precise work, should be located by plotting the electromotive forces as ordinates against amounts of titrating solution as abscisse. 258 Se To KCL <— — 33) 4914 4911 Roberts Electrometric Titration Outfit, with diagrammatic illustration of connections Hostetter and Roberts Titrating between Titration Unit and accessories Head ROBERTS ELECTROMETRIC TITRATION UNIT (continued) An arbitrary scale can, furthermore, be used for the slide wire with the zero so placed that the scale readings are always positive, although the electromotive force developed changes from negative to positive as the slider is moved along the scale. An electrometric unit embodying these features (see H. S. Roberts, Journal of the American Chemical Society, XLI: 1338, 1919) has been designed and manufactured by the Leeds & Northrup Company with the author’s cooperation and approval. In it the slide wire, galvanometer and keys are self-contained, with binding posts for external connection to the operating battery and titrating cell. The slide wire is provided with a scale of equal parts reading from 0 to 200 and a “‘tap-off’’ is made on the slide wire at the ‘‘60”’ of its scale. This arrangement provides for both positive and negative potentials of the varying electrode with reference to the standard electrode, but keeps the scale readings positive for all settings on the slide wire. If the scale readings are plotted against the volume of titrating solution added, the curves clearly show the inflection points indicating completion of the reaction. This unit will be found generally useful in all electrometric titrations where the electromotive force de- veloped at the electrodes of the titrating cell is to be balanced against a fall of potential along a slide wire and where arbitrary readings on the slide wire will answer the purpose. For precise work in the determination of ferric iron the Hostetter and Roberts Weighing Burette (see Journal of the American Chemical Society, XLI: 1350, 1919) is recommended for the dichromate solution. In this burette a small volume burette, 1 ml in 100ths, is used for the end-point, while the larger burette, 100 ml in 5 ml, is drawn upon for most of the titration. For use in conjunction with this or other burette and the Electrometric Unit, the Hostetter and Roberts Titration Head (see Journal of the American Chemical Society, XLI: 1340, 1919) is recommended because the neck of the flask containing the solution to be titrated can be covered to protect the solution from atmospheric contact and made to serve at the same time as a support for both the calomel electrode and the platinum electrode. This head is offered in sizes to fit both 50 ml and 500 ml Nonsol Erlenmeyer flasks. The calomel electrode vessel is not fused to the glass cap of the head but passes through a glass sleeve—not indicated in the diagram—and is readily removable. The tube carrying the platinum electrode is fused into the cap, but the glass tube carrying the platinum wire is inserted through a ground glass joint and is removable. The side arm of the platinum elec- trode tube permits the convenient introduction of carbon dioxide or nitrogen (free from oxygen) before and during titration for the maintenance of a neutral atmosphere and for stirring the solution when necessary. 4910. Roberts Electrometric Titration Unit, L. & N., as above described, with directions for use and diagram of connections, but without glassware or battery............0 00... 60.00 4911. Titration Head, Hostetter and Roberts, as above described, including the calomel electrode vessel, un- filled, and the platinum electrode, but without flask or burette. To fit Nonsol Erlenmeyer Flask No. 5344, size.......0 0.000. 0c eee, ... 50m] 500 ml Bla CHG ek RG eS a ee pg ah acts ee Men Ae 8.00 9.00 4912. ditto, but without calomel electrode vessel... .. 0.200.000. 5.00 6.00 4841. Calomel Electrode Vessel, Roberts, improved form, as used in the Hostetter and Roberts Titration Head. The bottom of the capillary is furnished straight for bending in the laboratory after insertion through the glass sleeve of the Titration Head and for suitable adjustment to the height of the Dersler See 2 cers cea tes es ae eee ett aree eee sea veciemem engey poem Rn Germ nt a 3.00 2466. Weighing Burette, Hostetter and Roberts, as above described and as designed primarily for electrometric titrations for conveneint delivery of small volumes near the end-point. Capacity of large reser- voir 100 ml with graduation interval of 5 ml; capacity of the small reservoir 1 ml, graduation FA CER AO: Oi canine stapseceesce tsi stee Vouenaln ane torab hone etna anne acer cd geen MRA Ae AGI eh an cen bie 10.00 HOSTETTER AND ROBERTS ELECTROMETRIC TITRATION OUTFIT, as described and illustrated above and with some recent improvements in the glassware as suggested by the authors in private communica- tions, consisting of: 4910. Roberts Electrometric Titration Unit, L. & N. 5344. Nonsol Erlenmeyer Flask, 500 ml. 4911. Hostetter and Roberts Titration Head, with cal- 2466. Hostetter and Roberts Weighing Burette. omel electrode and platinum electrode. 2090. Burgess Super-six Dry Cell. 4914. Complete Outfit, as above listed. ....... 20... e eee ece eee ete 80.28 ALOR: oF —tEb h R H T H O M A 8S C O M P A N_Y KELLEY ELECTROMETRIC TITRATION APPARATUS for the determination of Chromium, Vanadium and Manganese in steel and ferrous alloys and, with the addition of certain accessories, for the measurement of the conductivity of electrolytes and for the determination of H-ion concentrations. i qi 4920 4920 Kelley Electrometric Titration Apparatus—Front view. Kelley Electrometric Titration Apparatus—Rear view. _. This outfit is the result of work which was undertaken by Dr. G. L. Kelley, formerly Chief Chemist of the Midvale Steel and Ordnance Company, and his associates, in adapting the principles of electrometric titration to commercial methods of steel analysis. The problems encountered in this development work pointed out the desirable features of design in a commercial equipment. With the suggestions of Dr. Kelley as a basis, Leeds & Northrup Company designed the apparatus, developed the necessary equipment for adapting it to conductivity and hydrogen-ion measurements, and now manufacture it. The device has been successfully applied to the determination of Chromium, Vanadium and Manganese in steel and ferrous alloys. Determinations of Chromium and Vanadium in steel can be made on samples con- taining one or both of these elements. The presence of Molybdenum and Tungsten does not interfere. Manganese can be determined readily in the presence of both Vanadium and Chromium. : Although the apparatus is especially valuable in the analysis of steel and ferrous alloys, the principle involved in the operation of the apparatus has been applied in the determination of other elements than those already mentioned. _This is notably the case with Zine. It is also possible, with the addition of certain accessory apparatus, to use this outfit for the measurement of the conductivity of electrolytes, and for the determination of Hydrogen-ion concentrations. It is possible that other important applications will also be found. Description. The apparatus consists of a wooden case with an upright carrying the motor, burettes and elec- trodes. In the case are two dry cells, an adjustable resistance, and a reflecting galvanometer. On the upper surface of the case is a ground glass scale on which the light from the galvanometer is thrown. A knurled head inside of the case permits of adjusting the zero point of the galvanometer and another on the side controls the resistance. _, The standard carries the burettes, the electrodes, and the motor for driving the stirrer. In addition, provision has been made for a reservoir of the electrolyte which is used in the calomel cell. This makes possible, without change in its potential, the displacement of the impure electrolyte which may have accumulated in the tip of the electrode. A pan on an adjustable support, specially treated to resist acids, carries the beaker in which the titration is made. Two switches are mounted on the sides of the case, one of which controls the galvanometer light and motor, while the other closes the potentiometer circuit. 260 A OR VES He eR H. ke GED) GOr AM ASS Cr O Me. {Be ANY OY ae The calomel electrode rests in a metal collar attached to the upright. The glass stopcock allows liquid to flow into the cell from the reservoir to which it is connected by rubber tubing. When this stopcock is opened, the capillary tube is flushed, thus insuring the purity of the electrolyte in the cell. The cell may be filled through the opening, which is then closed. A platinum-tipped wire makes contact with the external cir- cuit. The capacity of the cell is about 100 ml. A small amount of mercury is placed in the bottom of the cell and covered with Hg,Cl». The cell is then filled with the neutral liquid, a normal solution of KC]. This gives a constant potential difference of about .56 volt between the Hg and the liquid, the Hg being + to the liquid. f The e.m.f. of the electrolytic cell is balanced against the fall of the potential across a slide wire in circuit with two dry cells and a resistance. The total resistance of the slide wire is about 50 ohms. This resistance can be varied, to secure a balance, by means of a knurled head on the outside of the case. __ A Leeds & Northrup Co. Reflecting Galvanometer is built into this outfit. This instrument is sufficiently sensitive for the purpose and has the further advantage of a very short period. It is rugged in construction and will withstand as much rough usage as an ordinary voltmeter. The image of the lamp filament is reflected to a translucent scale which is placed on the top of the box. This places the scale where it can most easily be seen by the operator while titrating. The lamp furnished with this instrument has a single straight filament of high brilliancy. A heating unit is mounted on a socket on the inside of the box for the purpose of keeping the galva- nometer circuit dry at all times and preventing possible ‘“‘leakage’’ due to moisture. The stirrer consists of a three-bladed glass propeller cemented into a brass rod and belted to a small elec- tric motor. This motor is securely attached to the upright and is equipped with a rheostat for variable speeds. The reservoir consists of an aspirator bottle, 500 ml. capacity, firmly attached to the upright. Two switches are mounted on the box; one controls the motor and galvanometer light, and the other throws in the potentiometer circuit. All connections, except to dry cells, are soldered and the insulation is designed to prevent all possible ‘“‘leaks.’’ All metal parts are treated with a special acid-resisting varnish. The measuring circuit is carefully insulated from the motor circuit. Volts Volts 1 30 15 20 0 18 ° CC of F250, C.C of Fe50, Fig. 1. Fig. 2. Principle—The Change of Oxidation Potential. If platinum and calomel electrodes are placed in an oxidiz- ing solution such as chromic acid, we have a cell with a definite e.m.f. On adding a reducing agent such as fer- rous sulphate, the change in potential will be small until the first excess of the reducing agent appears in the solu- tion. The change is then very striking, for the voltage of the cell which originally contained the oxidizing agent kedly from its first value. : ‘ os oe ee edlpsnel: electrode, which makes contact with the oxidizing solution through a siphon arm containing KCl or some other neutral salt, has a constant potential (.56 volt if normal KCl solution is used.) Since this salt does not enter into the reaction, the potential of the calomel electrode remains fixed throughout the reaction, all : i lace at the platinum electrode. t ; eae Pena to follow graphically the changes in potential which are known to take place during a titration. For this reason various curves were plotted, using the Kelley apparatus, anda voltmeter with a range of 1.5 volts. Electromotive forces were plotted as ordinates and ml. of reducing solution as abscissee. The curves, there- fore, show the changes in potential due to the reduction of the oxidizing solution. It should be noted in every case that at the end point of the reaction a very small amount of the titrating solution caused a large drop in potential. Fig. 1 illus:rates the changes that occur when a solution of K,Cr,0O; is titrated with FeSO,. The titration was carried out in a volume of 200 ml. in the presence of 25 ml of H»SOu (sp. gr. 1.58). One ml of the chromate solution corresponded to .000339 gr. of Cr and the FeSO, was of approximately the same strength. ; Twenty-three ml of the chromate solution was used. Point (1) on the curve corresponds to a potential of .766 volt, the difference between it and point (2) is .1 ml and only .004 volt. : ; The further addition of .1 ml of the reducing solution gives point (3) causing a change in potential of 313 volt, a very striking drop. This marks the end point of the reaction. After the end point is reached, the addition of an excess of FeSO, causes relatively little change in the potential, as is shown by the curve. Fig. 2 gives the curve representing the titration of a solution of K,Cr.0y, 1 ml equivalent to .001 gr. Cr, by FeSO, of approximately equal strength. The portion from A to B represents the direct titration of 21 ml of the chromate solution. The difference between points (1) and (2) on this portion of the curve corresponds to .05 ml and .005 volt. The addition of .1 ml more of the FeSO, caused a drop of .335 volt, again a very striking change. When past the end point by several drops of FeSO,, more K,Cr,0; was added, represented by the portion B C of the curve. Then more FeSO, was added, shown by the portion of the curve (CD), again causing the large decrease in potential from points (1) to point (2) of .29 volt for .05 ml FeSO. 261 A R T H U_ R Hea WT «Al -Or ME AS GC OMe Pe Ae NY. Operation. To operate the instrument, a beaker containing the solution to be analyzed is placed on the pan and the support raised and locked in position. The switch controlling the galvanometer light and motor is then closed. The other switch closes the potentiometer circuit and a slight turn of the knob controlling the resist- ance is sufficient to bring the beam of light on the scale. In titrating a series of solutions, this latter adjustment need be made only once. During the operation, which is quick, certain and convenient, the analyst watches the beam of light until a permanent change of potential is noted. In general, the first permanent large change marks the end point of the reaction. A rheostat for varying the speed of the motor stirrer is mounted on a casting attached to the box. Advantages—Determinations are made with an accuracy which can not be equalled by other methods. For example:—Chromium can be determined to .1°% where the Chromium content is as high as 20% of the sample. When the Cr content is from .20°% to 3% of the sample, an accuracy of .01% is easily obtainable; and for small amounts of Cr i. e. less than .20%, it is possible to obtain an accuracy of .002 to .003%. ge method is rapid, the saving in time being especially notable when a large number of determinations are made. Strong color or turbidity does not interfere with the determination since no chemical indicators are necessary. The end points are sharp and easily determined. Young men or women with very little experience in laboratory work are able to make accurate determina- tions of Chromium, Vanadium and Manganese in steel. Such analyses can be made by other methods only by men of large experience and a high degree of skill. All parts of the apparatus have been selected to give the greatest efficiency and are combined into a single rugged instrument. The apparatus can be moved about the laboratory readily, requiring only the connection of a plug with an electric light circuit. It is complete in that it carries a potentiometer system, a motor for the operation of the stirrer, and the two burettes for oxidizing and reducing solutions. List of Articles on Electrometric Titration by Dr. G. L. Kelley and Collaborators KELLEY, G. L. and Conant, J. B.—‘‘ Determination of Vanadium by Electrometric Titration.’’ Journal of the American Chemical Society, p. 341, 1916. KELLBY, G. L. and Conant, J. B.—‘ Determination of Chromium and Vanadium in Steel by Electrometric Titration.” Journal of Industrial and Engineering Chemistry, p. 719, 1916. KELLEY, G. L., ADas, J. R. and WILEY, J. A.—‘‘A Convenient Apparatus for Electrometric Titration Depending on the Change of Oxidation Potential and Its Application to the Determination of Small Quantities of Chromium in Steel.’”’ Journal of Industrial and Engineering Chemistry, p. 780, 1917. KELLEY, G. L., SPENCER, M. G., ILLINGWoRTH, C. B. and Gray, T.—‘‘ The Determination of Manganese in Steel in the Presence of Chromium and Vanadium by Electrometric Titration.” Journal of Industrial and Engineering Chemistry, p. 19, 1918. KELLEY, G. L. and WRIGHT, W. C.—‘‘Rapid Determination of Chromium in Steel by Electrometric Titration.’’ Iron Age, p. 1507, June 5, 1919. KELLEY, G. L., WILEY, J. A., BOHN, R. T. and WRIGHT, W. C.—‘‘ The Determination of Vanadium in Steel by Electrometric Titration. The Selective Oxidation of Vanadyl Salts by Nitric Acid in the Presence of Chromic Salts.’’ Journal of Industrial and Engineering Chemistry p. 632, 1919. KELLEY, G. L. and Boun, R. T.—‘‘An Electrometric Method for the Determination of Ferrocyanides, Depending on a Change in Oxidation Potential.”” Journal of the American Chemical Society, 41, No. 11, p. 1776, 1919. PRICE LIST 4920. Kelley Electrometric Titration Outfit, complete as shown in illustrations on page 260, including glass- ware consisting of Paired Burettes, Calomel Electrode Cell, Platinum Electrode, Aspirator Bottle, 500 ml capacity, and Glass Stirrer. With Universal motor for use on either 110 d.c., or 110 volt, GO CY. ClO AC Sein Bre Os Aree Mn AE shes hey DSRS ahs nifdk ey Sek tod Te aden echo ea bty ek apie Uae Seats ea 250.00 4922. ditto but for use on 220 volt, 60 cycle, a.c.. 0... ccc cence nee eeaee 265.00 4923. es Bey ES EDD) MONG aC ed teicher coro ave tate omen hate gd BM RE Tasks da a eee Rta Re beter ee 250.00 2410. Burettes, Paired, with straight glass stopcocks, 50 ml in 1/10, graduated at 20° C, with right and left-hand SLOPCOCKS) MRCP PAlb.. schemes oe tints Amat red me Nes OY eS Oh Uated heen Nenana Big Waites ack oan os 9.00 2110. Beaker, Pyrex Glass, Griffin low form, with spout, 800 ml capacity......................005- 40 4838. -Calomeli Electrode: Cell. 3060. a5 2s ies baa Sel nls ee eon eh erento eal mie yee alld ween 8.00 ASSO” “Platinuni Ble cto 5h hess acs coeetg oes res ee caret ico eto caer us oben here aa mal en Stes et AEE 2.00 4924. Glass Stirrer, without metal holder, to replace breakage. ........0.0. 000.0... e cee eee 1.70 2237. Aspirator Bottle, with nipple form outlet tube near bottom, 500 ml capacity................... -60 4925. Spiral Belt, to connect motor with stirrer. ........ 00000... c eee e ee eaes 75 4799. Lamp, only, 4 volts, for Galvanometer........ 00.0000 cece eee e ene eeeus 1.00 4926. Moving System, only, in interchangeable mount, for the d’Arsonval Galvanometer used in the Kelley Electrometric Titration Apparatus; for replacement.................. 00 ccc ccc ccucucues 30.00 ACCESSORY APPARATUS. With the addition of a voltmeter, a hydrogen electrode and a single contact key, the Kelley Apparatus can be used conveniently for the determinations of H-ion concentrations. Conductivity measurements can be readily made and end-points located by the addition of a conductivity cell, a Wheatstone Bridge and a portable A. C. Galvanometer, utilizing an ordinary 110-volt, a.c. 60-cycle circuit as a source of e.m.f. For H-ion concentration determinations 4852. Hydrogen Electrode, Hildebrand, with platinum electrode..........0 0.00. cece ccc ec eceeeece 5.75 4853. Adapter, for use with Hildebrand Hydrogen electrode...........0.0. 0000 ccc ccc ccc ceuacecees 15 9808. Voltmeter, Weston Portable Model 45, range 0 to 1.5 volts in 1 /100th volt divisions............ 41.25 4044-9 tion showed a tendency to destroy the cement joint. The new construction practi- | j | cally removes the possibility of leaky headpieces. 8 Each cylinder is furnished fitted with a lock-nut, two rubber washers and | | one fibre washer as required for use in glass mantles, etc., on negative pressure. Eorrom Where cylinders are used on positive pressure, the flat rubber washer and fibre wash- comevere| |_| | ers are, of course, unnecessary. The regular cylinders are tested by a twelve hour immersion in water to re- BARB tain from 6 to 12 lbs. air pressure without passing bubbles, this degree of fineness ries being that usually required for bacteriological work. The preliminary filters as used WASHERS in the manufacture of biologicals for removing albuminous material which tends to FIEER slow up the finer or higher pressure filters, are tested from 4 to 6 lbs. ecieas Each cylinder is seasoned and tested before leaving the factory ; and packed rere A | in individual cartons, with directions for use, with particular reference to improved nipple] | technique in cleaning, sterilizing and general handling, as followed by large users in the manufacture of biologicals. et ee nde See illustrations and prices on following page. 271 A R T H UR H. T H ©O M A 5 G “0 ‘M)-P A: IN _¥ IOX2ZIN. ed 5090 ; 5091 5105 5110 5112 5114 5090. ‘Filter Cylinders, Mandler Diatomaceous, as described on preceding page; regular series, tested to 6 to 12 lbs. air pressure. INUIMID CT ee cc onset hrs hag Ut Pb cece eu ten Sect ee 1 2 3 4 5 DIZEs I CMOS iste b Aree oat econ a ake a Ml Sen Pees tlenee neha 10 x2 8x1 pool Boks “aac Length of nipple, ‘nches....................0...... 4 2 2, 2 2 Diameter of nipple, inches....................0.4-. 4 5 Ps & Ba achive Preto ceri pent aN At rg ENG SR eae 4.00 3.00 2.50 1.25 1.15 10% discount in case containing.................... 24 12 72 144 144 5091. Filter Cylinder, Mandler Diatomaceous, No. la, 10 x 2 inches, with glazed porcelain headpiece and nipple, for filtering acids, etc. Tested 6 to 12 lbs. air pressure. Furnished in one size only. Each. 3.50 10% discount in case containing 24. 5092. Filter Cylinder, Mandler Diatomaceous, No.1-P. A preliminary filter for removing albuminous material in the manufacture of biologicals. Size 10 x 2 inches. Tested to 4 to 6 lbs. air pressure. AGH lam shrine ies a.e ot te ANC en SihcN Nat acs ot ae a aan Gopi per eee NH ep au nguatme ts 4.00 10% discount in original cases containing 24. 5094. Filter Cylinder, Allen Porcelain. This filter differs from those made of diatomaceous earth in that it will hold a much smaller organism and, therefore, must be used under a much higher pressure, i. e., from 14 to 25 lbs. They were developed to meet a need for the most exacting filtration require- ments, such as the filtration of Hayem’s solution and physiological serum, where the filter must not only be absolutely sterile but free from any particles of solid matter. They are made with metallic headpiece, and otherwise exactly same as No. 5090. Size, 10 x 2inches. Length of nipple, 2} inches. Diameter of nipple, !) inch. Each...................0....0....0.5. 6.00 10% discount in case containing 24. FILTER CYLINDERS, Berkefeld. As in pre-war years, these cylinders are furnished in three degrees ofjfineness designated as follows: ‘‘W’’—very fine or slow filtering, “‘N’—normal or medium filtering, and ‘*V”’— coarse or rapid filtering. 5100. Filter Cylinders, Berkefeld, with metallic headpieces. IN Cara DOr eicrene tis cnet n Fayecs pe eet oe ee une chest Meased ea te tew 1 2 13 3 20 S1Ze; INCheSsias xs eae ae mda et esos RA aN Ree ek 10 x2 8x1 5x1 24x 5 2x1 Beach," W? * Bin@ i.e 8 ties Vox c cetera s eae Giacsates 4.00 3.00 2.50 1.25 1.25 5101. 650 SANE IMPCGLUIN natch nasd ceo cine o Sea eae Cees 4.00 3.00 2.50 1.25 1.25 5102. Site EEN COAT SOS orb etn nea boii beeen nk bal plows 4.00 3.00 2.50 1.25 1.25 5105. Glass Mantles, Pyrex Glass, for use with any of the above cylinders. The use of Pyrex glass is of great advantage because of its low solubility, resistance to heat shock and great mechanical strength. These cylinders are made specially for us in our own private moulds. Outside dimensions, inches....................... 133 x43 11x22 53x23} 44x11} 2);x1} Diameter ofopenmg, nk kate dea ceee vanes t oa ¢ a v5 Suitable for cylinder size, inches.................. 10 x2 8xl 5 x1 24x & 13x 3 TEL CH ots ty alervaevee ett Gir le sce vaca entre nto ca See 1.75 1.25 1.00 15 .50 5110. Filter Cylinder, Chamberland-Pasteur, of porcelain, original French make, with glazed flange and nipple. Cylinder measures 200 x 25mm. Fineness “B,”’ ?. e., suitable only for pressure 2.0 5111. ditto, but fineness “F,” 2. ¢., of coarser texture and suitable for ordinary filtrations 2.50 5112. ‘Filter, of unglazed porcelain with flange at top. Cylinder is 115 mm long x 20 mm outside diameter x 16 mm inside diameter. Flange is 50 mm diameter 5113. ‘Filter, Pele or flask of unglazed porcelain, 200 mm high, diameter of bulb 125 mm. Capacity (a0 Eee eieenumeenr ee cciiar uatclt eee a gees ee eee er eriC ange nore ny mere RAL mn eNar cd A te reba ean 1.98 5114. Filter, Porous, of unglazed porcelain, tube shaped, closed at one end with flange on other end. Length 130 mm, outside diameter of tube 28 mm, inside diameter 20 mm, diameter of flange 35 mm. 50 272 5116. 5117. 5118. 5119. 5120. 5124. 5125. 5126. 5116 5118 5120 Filtering and Ampoule Filling Apparatus, for filtering sera and similar liquids for immediate delivery into Filter ampoules without exposure. The measuring tube on the side measures charges up to 2 ml. Complete with No. 5090 Mandler Filter 2} x } inch, and No. 5105 Pyrex Glass Mantle, 4} x 1} inch, as shown ansillistrationyec ce0e42 soc acnaan Bic tuesires Abe nia cede andlned ions aa ad tn sini ere aah eA baly 25.00 Apparatus, Chamberland, System Pasteur, as used for serums, toxins, etc. Capacity of pressure cylinder two quarts. Mounted on tripod, with manometer, pressure pump and connections. This apparatus is intended for use with Chamberland Filter Cylinder “B,”’ our No. 5110. Price includes ONG-CVING OF fin 3 eee ek 3 ogi Moiese cele oe ete ee ed ewe, ee Denes EAE wade ey Sea 90.00 ditto, but without hand pump; for connection to high pressure line........................ 80.00 Filter Filter Apparatus, Pressure, for filtration of toxins, etc., consisting of a cast-iron bowl enameled inside, with air-tight cover held down by four wing nuts, with pressure cock attached and bracket for fastening on the wall. Below is a detachable nickel-plated metal cylinder with ground-in stopper, taking a 10 x 2-inch Mandler filter cylinder. Price does not include the Mandler filter cylinder. Capacity of iron bowlyeallonss..... ecco eta ees pee teeny ee 1 23 4 Dimensions of bowl, inches............ 0.000.000 eee eee ee 5+ x11} 8x 12% 104x123 HMachixg shes. es als ge et ee Sten Bye ct redo recat Le gee Rae 60.00 75.00 95.00 Apparatus for Pressure, Hill, for the use of hydraulic pressure. (See illustration on page 274.) By this method the material to be filtered is separated from the pressure medium by a soft rubber membrane. This avoids foaming and also permits the use of water instead of air pressure. City water service will usually furnish 40 lbs. per square inch, which is about three times the pressure of a vacuum filter. The force pump supplied increases this to 300 lbs. per square inch. At the left top of the chamber is a block tin funnel and tube, through which the liquid is intro- duced to the filter. To this tube inside the chamber a flexible rubber tube connects the soft rubber filter bag. Within this bag is placed the bougie, the nozzle of which fits through a bushing at the bottom of the filter chamber and delivers the filtered liquid below. The side funnel tube of tin is soldered into a brass nut, which, together with the tube, is readily removable for sterilization. There is a rubber washer at the base of this nut and a screw stopper in the funnel to prevent back flow under pressure. When filled the screw plug is inserted in the funnel and the contents of the bag may be subjected to the required pressure. The three-way cock enables one to admit water to the chamber, to close the chamber from the service pipe, leaving it under pressure, and to drain the chamber. The vertical pipe with pressure gauge at the top is an air pressure storage chamber and is for the purpose of keeping a fairly uniform pressure without continuous pumping. There is a vent cap at the top. This should be kept tightly closed. If it leaks, air will be gradually forced out and the chamber will be kept filled with water. In that case its usefulness would be temporarily impaired and, moreover, a single stroke of the pump would then raise the pressure Complete with one 8 x 1 inch Mandler Filter Cylinder and 1 liter rubber beyond a safe point. Panes hs oucsr aee ees oie aac eae et a A repent ceie NG Soca Se ae AO AR Re Ea aoe aie veneer 154.75 Rubber:Bag, only; liter capacity wo is. 656 eee tees tee emeLeh alae wees tee rae oe “cc 150 anPCApACit ys sien aces cee esen ROM pam messed Some Man neta blimey adeat Gatun ee 5124 (Described on page 273.) Filter Cones, Alundum. These can be used in any 60° funnel by stretching a wide band of rubber tubing over the funnel. They have a large filtering area and can be thoroughly washed from all soluble salts and are recommended for the filtration of gelatinous and slow filtering solutions. They can be cleansed by reverse washing, reduced to a constant weight by ignition and used repeatedly. Each cone is supplied with wire stand as shown in illustration. Diameter; InCheSic< v5.5 seed ee ee a ee eg gee 13 23 3 4} Capacity. cmilias cies a psetam aa oasir Gate ec oe a Th ee eC ee Meee 15 35 60 250 5136. Mixture RA 320 Dense. Each............................. .30 .60 .85 1.50 5137. “RA 320 Medium.» Each:... 14. 34.co0h den pahaae ema ec .30 .60 85 1.50 5138. fo SRA (322-Porous:,, "achyg ecko Maes He ee .30 -60 85 1.50 5139. Rubber Gasket, for use with alundum Filter Cones.................. 05 .05 — 10 Filter Discs, Alundum. These discs can be advantageously used to replace perforated porcelain plates in many operations, obviating the necessity of preparing an asbetsos mat. washing and ignition, permitting of their repeated use. They are easily cleaned by reverse Edges are moulded to a 60° bevel to fit funnels. 1 2 Diameter, inches................. 3 3 4 5 6 7 8 FRNICKMESS 3 oho Re kt ee ocenntiganeth nee ie Te as t Ps 3 ifs 4 i 5142. Mixture RA 225 Medium. Each.... .40 45 50 -60 75) 61.00 1.25 1.50 1.75 5143. “RA 98 Porous. Each... .40 -45 50 .60 .75061.00 1.25 1.50 1.75 8286. Filter Discs, Glazed Porcelain, beveled at an angle of 60°, and perforated for use in funnels as filter discs. Diameter, mm Thickness, mm Diameterof holes; MM in. 0 ciciesvoe evan ei oa gous s wnat ieee ac 22 25 2 3 4 oe! 24 .24 4 4 1 1.5 30 388 50 60 75 4 5 1 2.5 28.36 .46 .54 .72 Filter Dishes, Alundum. Will fit into the top of any 60° funnel and affords a rapid means of filtering large amounts by suction. and RA 98. Diameter, inches Depth, inches Gapacitys ml org soars eas SS De ee ere Paes bene ad Gee Mixture RA 84, Dense. 5146. 5147. 5148. 5149. “cc “c Rubber Gasket, for use with alundum filter dishes, 300 ml capacity RA 360, Medium. Each RA 98, Porous. 4 2 150 1.25 1.25 1.25 Well adapted to organic work. Supplied in three degrees of porosity, RA 84, RA 360 55 2 300 2.00 2.00 2.00 50 All current merchandise listed in this catalogue is carried in our own stock for immediate delivery, with the exception of a very few items, of which prompt factory shipment is usually possible. The maintenance of so large and varied a stock is to be understood as subject to certain interrup- tions beyond our control in the way of manufacturers’ and transportation delays, strikes, war, etc. | 274 A R T H U_ R H. T H OF M AS C O M P A N Y LOW ASH RAPID FILTERING A.D.L any ease Rien RS Tata nce ARTHUR D. LITTLE inc. ccs (FILTER PAPE ARTHUR H.THOMAS CO. PHILADELPHIA 5160 5164 ; AMERICAN STANDARD FILTER PAPER. While sold by us for the past twenty years, the merits of this paper in comparison with standard papers of European make were not fully recognized by us or by our cus- tomers until the war scarcity of foreign-made papers rendered its use imperative by many accustomed to the use of more expensive imported papers. The continued reports of these users as to the satisfactory performance of this paper led us to make some comparative tests as to its rapidity, retention of fine precipitates and weight of ash with the following results: Rapidity—Distilled water at 27° C was passed through, maintaining a constant level in a 60° funnel. After the passage of 50 ml the rate of flow was measured with a stop-watch. Rate 33 ml per minute. Retention of Fine Precipitates—A fixed quantity of barium sulphate was filtered and the paper and precipitate ignited and _.. weighed. After deducting the weight of the ash, this paper was found to uniformly retain barium sulphate. Weight of Ash—For circles 90 mm diameter, 0.0017 gram. _, These results show that as compared with the three well-known makes of foreign paper of the same classification against which these tests were made, our No. 5160 American Standard Filter Paper is equal in rapidity to the fastest of the foreign papers tested, equal to all of them in retention of Barium Sulphate and equal to the average of the foreign papers in weight of ash, one foreign paper showing a greater ash residue and one a less. Suitable for all analytical purposes other than those requiring the use of a paper extracted with hydrochloric and hydrofluoric acids. 5160. Filter Paper, American Standard, as above described. Each pack of 100 filters is packed in a convenient paper carton, so paper is kept clean until it is entirely used. Diameter, mm.................. 15 90 100 110 125 150 180 Per pack of 100................ 17 19 21 .24 .20 .34 44 Diameter, mm ................ 200 250 330 380 450 500 600 Per pack of 100................ 56 78 1.28 1.62 2.25 2.85 4.90 10% discount in lots of 100 packs. 20% discount in lots of 500 packs. 5161. Filter Paper, American Standard, as above described, in sheets 480 x 480 mm. Per package of 120 sheets............. 3.85 Per package of 480 sheets............ 14.00 A.D.L. DOUBLE WASHED QUANTITATIVE FILTER PAPER. After two years of extensive investi- gation and tests of all brands of quantitative filter paper, Arthur D. Little, Inc., have developed in their labor- atories and in their own experimental paper mill a close textured filter paper with the highest speed of filtration consistent with the retention of fine precipitates. This filter paper is the fastest paper on the market when its ability to hold fine precipitates, such as barium sulphate, is considered. It is washed with both hydrochloric and hydrofluoric acids. The paper machine on which this paper is made is operated with distilled water, which we believe is not done elsewhere in the world. During the manufacture, a sample is taken tor laboratory test from every 20 tbs as it comes off the machine. The results of these tests in the production of actual stock now offered for sale are as follows: Penetra bility ss 55.535 508 Sas bee oo Saas He eee AES Sena cae, Rete ian wen Gah 15-25 seconds Retention- of Ba SO pin he.5 ise os ee a IS eet ts esc a a endear teoatnnat okeieete at Shee knead Sane Excellent Babes ate cigar stone bts ON ese sae aE UAL EEN IN CN Se neh eure POUL WN EE ae fata veces 0.008% Ash per llemcircle........ Aico ctnclodele data, lantchade aearavtettneay ‘lege dec alstwane wpa seere Br enetercccssantect mata 0.00006 gram Thickness,inch.......... Ue Some Bethe PIN Wiest td ADRS ENS meshed ccs taeehie fae encanto ean the 0.0070-0.0090 Bursting Strength, Ibs. per sq. in... 20... 0.6. 12 minimum The methods used in the tests controlling the manufacture of the Paper are as follows: Penetrability—The figure for penetrability is obtained upon the “‘Little’’ tester and represents the number of seconds which is required for 100 ml of water to pass through a 50 mm circle of the paper under a constant 9 inch head. 25 seconds represents the maximum penetrability figure obtained. On the other hand, many runs of the paper show a penetrability faster than 15 seconds. The penetrability of the fastest papers on the market (which are not intended to hold BaSO4) is about 10 seconds. Retention of BaSO4—In making this test the barium sulphate is always precipitated under the same conditions and in such a manner as to give a much finer precipitate than would ordinarily be obtained in good practice. No paper passes the laboratory tests which will not hold the precipitate formed under these unusually severe conditions. _ : Thickness and Bursting Strength—While the thickness figure is not used as a basis for acceptance or rejection, the paper is made within the above limits and the constant checking of the thickness aids in making a uniform paper. Most of the paper shows a bursting strength of approximately 15 Ibs per square inch. This test has a direct bearing upon the resistance of the paper to the ordinary handling. It has been found that Bho Dunetine strength of this paper is somewhat higher than that of most other papers which are intended 0 neral laboratory work. EE rE Diieal Tianection vhs paper which has passed the specifications of the laboratory tests is then cut into circles of various sizes and every circle is submitted to physical inspection. No paper passes this inspection which shows pin holes or thin spots when placed over a 50 watt incandescent lamp, or which shows objectionable dirt specks. Furthermore, all paper is thrown out on this inspection which presents an unsightly appearance on account of ragged edges, etc. Other papers which are at present on the market have been subjected to this inspection and as high as 30% of some of them would be rejected by this standard. 5164. Filter Paper, A. D. L. Double Washed Quantitative, as above described. SIZe; NIMs eter sees ates emer a 55 70 90 110 125 150 185 Weight per circle, grams....... 0.1930 0.3100 0.5200 0.7700 0.9900 1.4300 1.9500 Ash per circle, grams.......... .000015 .000024 .00004 .00006 .00008 .00011 .00017 Per box of 100 circles......... 1.10 1.20 1.70 2.00 2.30 2.70 3.60 5% discount in cartons containing 10 boxes. 10% discount in case containing 100 boxes. 275 5170 Label on front of pack. Label on back of pack MUNKTELL SWEDISH FILTER PAPER. For many years this famous brand of Swedish filter paper has been considered by many chemists to be superior to all others. The excellent quality of the paper has been ascribed by some to fortunate circumstances attending its manufacturing, such as the unusual purity of the water available and the cold climate. This paper is justly celebrated for a remarkable uniformity in the important properties of the several numbers. 5168. Filter Paper, Munktell, No. 00. For special scientific work—washed in hydrofluoric and hydrochloric acids. Cut in round filters, 100 filters ‘n a package, five packages in a box of birchbark. Diameter, mm.... 55 70 90 110 125 150 185 Ashes, gram...... 0.000011 0.000018 0.000030 0.000045 0.000058 0.000083 0.000126 Per pack of 100.... 1.57 1.73 2.52 3.15 3.47 3.94 6.62 “box of 5 packs.. 7.50 8.25 12.00 15.00 16.50 18.75 31.50 5170. Filter Paper, Munktell, No. 0. Washed with hydrochloric acid, removing traces of iron, alumina, lime, etc The ash is reduced to a minimum, and a high standard of purity is secured. A uniform and quick filter, retaining fine precipitates, adapted to the most precise requirements of analytical work. Cut in round filters, 100 filters in a package, five packages in a box of birchbark. Diameter, mm... . 55 70 90 110 125 150 185 Ashes, gram...... 0.000060 0.00010 0.00017 0.00025 0.00033 0.00046 0.00070 Per pack of 100.... .63 .85 1.32 1.73 1.98 2.68 3.94 “box of 5 packs. 3.00 4.05 6.30 8.25 9.45 12.75 18.75 5171. ditto, but in sheets 480 x 480 mm. Per quire................ ..... tae Rls Awe he en ah 7.50 TP UNA Giant sy San oa ore a en a ae Sete cone 135.00 5172. Filter Paper, Munktell, No. 0A. A new grade double acid washed paper similar to the No. 00, but filtering more rapidly. Cut in round filters, 100 in a package; five packages in a box of birchbark. PPATIVE LET; TAS ob yess Basset as Ke A eit eee ane een aes 90 110 125 150 Per pack of 100......... ee ee ee ee 2.52 3.15 3.47 3.94 “box of 5 packs...... Aeirhast) Bite pect Died ae he eke 12.00 15.00 16.50 18.75 5174. Filter Paper, Munktell, No. 0B, washed in hydrochloric acid. Same quality as No. 5170, but somewhat heavier, filtering more rapidly and retaining the finest precipitates. This is a new paper and will be found satisfactory for the most precise analytical work. Cut in round filters, 109 in a package, five packages in a box of birchbark. AB ie beatsinsvase ab ogie, saniedrs Memon rman eaten be ee aye eant Atel te Breve eet eb ee aan 90 110 125 150 Per packiol: LOQs 0 cxis cone. 2 eee hse Me erie cena leo 1.98 2.20 3.00 ES “DOXdOL sD“ PACKS damm hehe oko ae tiene Cee rien. Peo) 9.45 10.50 14.25 5176. Filter Paper, Munktell, No. 1F. The Original Swedish Paper. Of best linen material, by some claimed to be the most perfect filtering paper made; leaves one-third less ash than formerly, probably the smallest amount of any of unwashed paper. Cut in round filters, 100 filters in a package, five packages in a box of birchbark. Diameter, mm.... 55 70 90 110 125 150 185 Ashes, gram....... 0.00014 0.00023 0.00038 0.00056 0.00073 0.00105 0.00161 Per pack of 100..... .35 -50 .79 .94 1.26 1.57 2.36 “box of 5 packs.. 1.65 2.40 3.75 4.50 6.00 7.50 11.25 5177. ditto, but in sheets 480 x 480 mm................... dees POT QUIRGs Ia Mi Sy by ent ad A 3.60 POE TEAM es io 5-153 ee ay aan 60.00 5178. Filter Paper, Munktell, No. 2. A pure white linen paper of medium thickness, not as closely made, therefore more rapid in filtration. A superior paper for all laboratory work. Diameter, mm... . 55 70) 90 110 125 150 185 Ashes, gram....... 0.00018 0.00030 0.00051 0.00074 0.00095 0.00138 0.00209 Per pack of 100..... 32 Al -63 82 -98 1.26 1.67 “box of 5 packs. . 1.50 1.95 3.00 3.90 4.65 6.00 7.95 5179. ditto, but in sheets 480 x 480 mm.......................... Per quire....... Shain Settee nee O80 Perream.... ..... ... . .. 51.00 5200. 5206. 5208. WHATMAN ENGLISH FILTER PAPERS. These papers, first produced in 1915 under difficult circum- stances incident to war conditions, in the mills of W. & R. Balston, Ltd., makers of the famous Whatman drawing and other hand-made papers, successfully met a great need for quantitative filter papers during the period when other European papers were unavailable. Since that time constant improvements have been effected and maintained in all grades, which are now of sufficient variety to meet all laboratory requirements. Filter Paper, Whatman No. 1. A high grade, rapid Filter Paper for general qualitative work in edu- cational laboratories, and in industrial laboratories for filtering ordinary precipitates when the ash weight of the paper is of no consequence. This paper is widely used in the determination of phosphorus for the filtration of the yellow ammonium-phospho-molybdate precipitate when obtained by long digestion as in fertilizer analysis; also widely used in sugar laboratories. Diameter, MM... c2 saeawsasad seas va hae me A rvigcihea Mehran 70 90 110 125 Weight of ash per circle, grams. .... iirc tyne . 00073 0012. 00175 0023 Per pack of 1005 2 :as Sena oonc nes ceed SA eich Oe eas 20 24 -28 .37 PTaMMe ter aM Mie ss eas. cps, akaees eel eee Pee etoeee ; 150 185 240 270 320 Weight of ash per circle, grams............... . 00326 .00496 Soe Seine! ae Per pack of 100. 0c ci eta eee ne nee ees 51 71 1.25 1.48 2.30 ditto, but in sheets 18! by 22} inches. Per 100 sheets...................... aaa ere 4.45 Per reamyce 3) 6 wen pees Py tegh shies deotum t,o wet nae nee onl re ORO Filter Paper, Whatman No. 2. A qualitative paper similar to No. 1 in its general characteristics, but heavier. It retains fine precipitates and filters rapidly. This is the standard grade for analytical purposes and is especially suited for use in the qualitative analysis of the alkaline earths, and in other analyses where fine precipitates of a crystalline nature are encountered; also extensively used in fertilizer, steel and ore mining laboratories. TiaMetersmMin 4 oe hia A nee acti eee 70 90 110 125 150 185 240 Weight of ash per circle, grams...... __ .00086 .0013 .0012 0027 0038 .0058 Per pack of 100..............--.-- 27 .34 -42 52 74 1.04 1.78 ditto, but in sheets 18}. by 22} inches. Per POO SECS. hee A ee es Pa 6.85 (POT P@AaTee co cud seacwals ender steed Momence es eS 31.10 Filter Paper, Whatman No. 4. A soft paper of more open texture than No. 1 or 2; extremely rapid, Filter but not recommended for use with the finest precipitates, for which purpose No. 2 should be em- ployed. Recommended for the very rapid and perfect filtration of gelatinous and large-particle precipitates such as ferric hydroxide, aluminum hydroxide, etc., and for pharmaceutical purposes, filtering fruit juices, syrups, oils, etc. Widely used in copper and other ore mining, sugar and cement laboratories. Diameter: MMs a6 vac ee endear tN eee ee ae 55 70 90 110 125 Weight of ash per circle, grams.........---------- 00038 . 00061 001.0015 .0019 Per pack of 100..........---.---005- Rae Nef a 27 30 -40 50 .65 Diameter,mm.......-------055 DR recat nso atest 150 185 240 270 320 Weight of ash per circle, grams...........-- Jeeees 0028 0043... Rice ees Per pack of 100... .....---- 0-252 e eter eee -90 1.30 2.22 2.70 4.10 Paper, Whatman No. 40. A double-acid-washed paper, subjected to the treatment of hydro- chloric and hydrofluoric acids which extract all traces of silicious matter. A paper of very low ash which filters rapidly and retains fine precipitates. This is the standard double-washed grade for analytical purposes. Recommended for general gravimetric quantitative work, for barium sulphate when properly precipitated and filtered in hot solution, and for lead sulphate even when precipitated in the cold; especially suitable for crystalline precipitates such as magnesium- ammonium-sulphate, etc. For precipitates that ordinarily are difficult to filter, see Whatman No. 42. iameter,mm........-----: 55 70 90 110 125 150 185 Waoight of eh per circle, grams .000028 —.000046 000076 00011 00015-00021 00035 Per pack of 100..........--. 1.10 1.20 1.70 2.00 2.30 2.70 3.60 Filter Paper, Whatman No. 41. A double-acid-washed paper of the same quality as No. 40 but more open in texture, therefore filtering more rapidly. For rapid quantitative work with such pre- cipitates as do not readily pass through the paper. Especially suitable for iron, aluminum and other gelatinous precipitates which can be filtered quickly and washed rapidly and easily; also widely used in determining silicon in iron and steel analysis. Sn St caveo PATE oe alesoa) Sooke PR He ROE ia Pigs Pudi Hlanepni ra eanreiegea 90 110 125 D eter, MM... 1.2... cree teers Weight of ash per circle, grams. ...... 6-060 e eee eee 000082 _ 00012 00016 Per pack of 100... 0.0.6.0 cece teen nett tenet nen : 1.70 2.00 2.30 5210. ‘Filter 5212. ‘Filter 5214. Filter 5216. Filter Paper, Whatman No. 42. A double-acid-washed paper similar in its chemical qualities to Nos. 40 and 41, but differing in physical properties, being much harder and extremely close in texture; slower in filtration than No. 40, therefore recommended for use preferably with vacuum, and whenever possible, as folded filters. Recommended for the same general quantitative purposes as No. 40, but especially for the finest precipitates that ordinarily are filtered with difficulty, such as metastannic acid, and for such precipitates as barium sulphate, etc., when circumstances do not allow them to be precipitated in hot solution. Diameter,mm.............. 55 70 90 110 125 150 185 Weight of ash per circle, grams .000028 .000046 .000076 .00011 .00015 .00021 .00035 Per pack of 100............. 1.10 1.20 1.70 2.00 2.30 2.70 3.60 Paper, Whatman No. 43. A double-acid-washed paper identical with No. 40, but subjected to an additional chemical process that renders it fat-free. - Recommended for the recovery of the ether extract in the Rose-Gottlieb fat test, and for other purposes where the advantages of a fat-free paper are obvious. Diameter, Mm... 0.2. es mpad ances 55 70 90 110 125 150 Weight of ash per circle, grams...... .000017 .000027 .000046 .000068 .000089 .00013 Per pack of 100................... 1.35 1.50 2.20 2.55 2.80 3.60 Paper, Whatman No. 44. A double-acid-washed paper of thinner substance than Nos. 40 to 43 and with lower ash content. This paper will readily retain the finest precipitates but is slightly slower in filtration than No. 40. Recommended for use where the greatest possible degree of accuracy in quantitative work is required. Diameter Mins. fo 5. thats Soaks sete eee ates 70 90 110 125 150 Weight of ash per circle, grams................ .000025 .000042 .000062 .00008 .00012 Per pack:of 100.45 css ee kind vee gt te eS 1.50 2.20 2.55 2.80 3.60 NUINE C/O WHATMAN | 44, 100 — FENED FiteR CON? J Se eed 5218, 5220 5222 Paper, Whatman No. 50. A very tough paper, specially hardened by treatment with nitric acid which will resist great pressure and retain the very finest precipitates. This paper can be used repeatedly, the hard, smooth surface admitting of precipitates being scraped or washed off with- out injury to the paper, and is especially adapted for use with vacuum. Recommended for the filtration under vacuum of very fine precipitates (almost colloidal), corrosive liquids such as acids and strong alkalies, and for other purposes when it is desired to transfer a precipitate with- out ignition. Widely used for collecting the globulin precipitate in the manufacture of diphtheria antitoxin. Diameter,mm........... 90 110 125 150 185 240 400 500 Per pack of 100.......... 1.70 2.00 2.30 2.70 3.60 6.10 15.75 20.85 5218. Filter Paper, Folded, Whatman No. 12, made of strong, high quality paper, folded in a special way to prevent tearing at the point. Diameter, MMs 52s saree as ee 125 150 185 240 320 385 500 Per pack of 100.................. 80 1.00 1.20 1.80 2.80 3.50 5.50 5220. Filter Paper, Folded, Whatman No. 14, similar to No. 5218, but with parchmentized points to prevent tearing even under considerable pressure. PVAMELE RMI es cs sige a eS Atos ce ceed cre eee noose oie ets ea aac ook GA eetoten eat es 320 385 500 ‘Per ipack Of 1002 25.45 scanned AG nas PA Soe ee ees. (aan wt . 8.20 4.00 6.40 5222. Filter Cones, Whatman No. 51, consisting of semi-circular discs of hardened paper for folding. An excel- lent substitute for platinum cones. Diameter, mm............. 55 70 90 110 125 150 185 240 Per pack of 100............ 70 -90 1.40 1.60 1.80 2.10 2.80 4.80 278 A R T H U_R H. Tr CHE Or iM Ae SS Gc 0 M P A N ¥ 5224 5226 5224. Filter Paper, Whatman No. 120, Drop Reaction, providing rapid absorption within a limited area. This paper is preferred to porcelain plates for many analyses as it gives a more visible reaction. In sheets: 140 by 220mm iis 5:2 acct garcons sandisk Gane arizceetels Gecuaics POP QUiLe se ion ane atin eas 1.30 Per 100 sheets................. 4.25 5226. Filter Paper, Black, Whatman No. 29. A deep black paper for filtering colored sediments, etc. The most minute traces of light colored sediment are easily perceptible on this paper. Diameter,mm..................... 55 70 90 110 125 150 185 Per pack of 100.................... 34 40 50 .60 -75 1.04 1.47 aa y ey SS Oe koa wes Sed as yNensin? 7 5228 5230 5228. Paper, Whatman, No. 100, fat extracted, for milk analysis. In strips 580 by 65 mm. Number-ofistripsin ‘packages «Sci 2G devs. stig hod png scan Red ana gb Shee da 50 100 Per Ppackag ence crcse tae enh Potts tains Aen 1S A yeh Me eae Ay, i 2 Bee ee 2.80 5.20 5230. Filter Paper Strips, Whatman No. 130, unsensitized, for arsenic determinations. These strips are made from the highest grade Whatman paper of a stout substance so as to insure rigidity. Size 120 by 2} mm, to fit standard size arsenic tubes. Per box of 1000 strips....................... 1.25 5259 5250. Filter Paper for Agar. A heavy white paper with a roughened surface which tends to prevent adherence to glass funnel in filtration of agar in the preparation of culture media. In sheets 40 x 40 cm. Per 25 sheets.......... 1.25 Per 100 sheets.......... 4.50 Per 500 sheets.......... 20.00 5252. Filter Paper, Bibulous. A thin white paper of good absorbent qualities. In sheets 15 x 18 inches. Per quire........ esesee 3440: PCR POA 55 w oice th rarer tire 2 eset aoe 7.50 5254. Filter Paper, Chardin, Folded, recommended for filtering agar in the preparation of culture media. These filters are very carefully folded and are packed in boxes containing 50 of the 32-cm size and 25 of the 50-cm size. Diameter; Gis «jG: 8 55.5 iiss Se aha AE Be eS eel 82 50 PECADO Kee cee ee ee eons ran as Siaeea tener aE ventas Oborreeek Reanim: ol eae atone tA Palate tO 2.00 2.00 5256. Filter Paper, Chardin, in sheets 50 cm square. Per package of 25 sheets..................... 2.00 5258. Filter Paper, Prat-Dumas, White, original French make, suitable for a great variety of work, among which is the filtration of beef bouillon and other culture media which must be filtered while very hot. Also used in the rough filtration work in connection with the concentration of diphtheria antitoxin, although the collection of the end precipitate in such work must be done on a paper of harder surface. Diameter, mm............. 75 100 125 150 200 250 375 500 Per pack of 100............ .20 .30 .35 -40 -50 -65 1.15 1.95 5259. ditto, but folded. Diameter, mm............. 75 100 125 150 200 250 375 500 Per pack of 100............ 50 -70 80 1.09 1.10 1.30 2.25 3.10 5260. ditto, but in sheets 17 x 21 inches. Per quire............... 0.006. 00eeeceeeeee 45 Per real. 3.2 0c de See eee MPS geteh t pokes Weeki 7.25 279 T H U R He. T H O M AS CG. - OM OP A ON: VY: 5262. 5270. 5276. 5278. 5279. 6264 Filter Paper, Baker & Adamson “‘A’’ Quality, thin paper, very rapid filtering, for general analytical work Very low ash. Double washed. Diameter, mm... 90 110 125 150 AShian ea Ch: Papers cc 6 ot 2 pect enid ce bee tin castes .00003 .00005 .000065 .000093 Per pack of 100% Sanches een oe oe oe ee a 1.70 2.15 3.40 4.20 Filter Paper, Folded, J. G. No. 588, for general use in the filtration of solutions of salts, slightly sweetened spirits, etc. Made of the purest material and entirely free from chlorine and acids. Diameter, mm.................... 125 150 185 240 320 385 500 Per pack of 100.................. .85 1.25 1.25 L75 3.75 4.00 5.00 Filter Paper, C. S. & S. No. 589 “Black Ribbon.’’ Washed in hydrochloric and hydrofluoric acid, of soft and very loose composition, filtering very quickly. Used for deposits which do not pass through easily, as is the case with many metals. Specially adapted for use in laboratories of metallurgy. For BaSO, and similar deposits passing through easily, these filters should not be used. PTA METER AMIE 440699 tg, ead ore males Sytem a rae gh coat) a iedln wep eae narnia ly chane dey 90 110 ASHOSs SORA seed oo eee oo Serco he eh tee ee ee ene ee eS .00011 .00017 (Per pack OrslO ewes dt cry At yn dirsotaccd eae he lancer hans Comadh oranda ee atu eel Cag eancnAS eels 1.70 2.00 Filter Paper, C. S. & S. No. 589 ‘“‘White Ribbon.’’ Washed in hydrochloric and hydrofluoric acid. Suit- able for most analytical purposes. These filters filter quickly and retain a properly treated deposit of BaSO.. WDiamMeter MTs. ins nk bette in aoe) 5 ate wee eas bs Rains Rita aes Cee, Be 90 110 MA SIOS3S: CRAIN gcc cote nel ote ctor ice cee ee. pacrny mat aunt antec HES ee ee peace, 0001 -00017 Per packot: 1002 masa Gea ee Re OE AS Sree ah tg td we eke 1.70 2.00 Filter Paper, Alpha. A smooth surface high grade, white paper of close texture. Recommended for pur- poses requiring a very retentive paper. Widely used for students’ requirements in schools and colleges, by physicians in urine analysis, etc., and by manufacturing chemists and pharmacists for purposes requiring a very retentive paper. Diameter; Mm. sos. Gh ees ea ws 55 70 90 100 110 130 150 Per pack of 100.................. 10 Al 12 14 16 19 25 Diameter MMs... 222 20 hone hee ees 180 200 250 330 400 450 500 Per pack of 100.................. 33 42 -60 -90 1.37 1.81 2.20 ditto, but in sheets, 20 x 20 inches. A smooth white paper suitable for a great variety of quali- tative work because of its smooth surface and good absorbent quality. Is very suitable for blotting micro slides, and for drying crystals, precipitates, etc. Per quire........................ 55 PORST Cas oP yea we ton ine, een ne ah ced 8.20 Filter Paper Clippings. These are small clippings left in cutting our stock circles of No. 5160 Filter Paper. They have been found most satisfactory for use in the laboratory manufacture of filter paper pulp, particularly such as required in the filtration of various immune sera, vaccines and other biological products. Perl baces2 serie, heat eae wenn, dec) ees Sy rut ace hate ean see thas .30 Filter Paper Pulp, made of ashless stock, thoroughly washed. As used in metallurgical laboratories. TmeCarton: COM balnin Cioves oo eu ape hia Sel eck ach eee and Sleede tdoer wean BR Pena tote te Duce ts 1 lb. 10 Ibs. PGT CARGO Tare cee cesses seo eee ae PA neces ince, eon ah cane Gili es erase Cele ety LEO: aaa ese 2.45 22.00 Filter Paper Box, of japanned tin, holding five sizes of filters from 75 to 200 mm diameter. Very con- venient in the laboratory as it provides ready access to clean filters at all times.......... 4.00 Filter Press, Round Pattern, consisting of funnel, pump, pressure gauge, two filter plates, two head plates, three frames, pan and supply of filter paper and cloth. With all parts of iron with the exception of the check-valves and discharge cocks... 2.0.0... ccc ee cece sense enevaeane 114.00 ditto, but with all parts coming in contact with liquid made of brass............... 00000005 162.00 280 Aco oRy i He Ue oR H. T H OF M A S$ Cc O M P A N _ Y 5289 5290 5292 5294 5296 5284. Filter Pump, or Aspirator, Chapman, of polished brass. For operation under water pressure either on faucet or directly connected to water supply pipe. Usenet an Chess see as certs ees Ae kad tend there. sa ACL) LA aes hho Slee ee 3 43 53 For size ‘‘iron pipe” thread, inches................. Reha ee es a 3 al 4 Bia chee enanede rath es tat Picea te tate ered ees WP ekedethe Che Aer ghey oh “1.45 ~=«1.60—«*2..80 5286. Filter Pump, or Aspirator, new patent form, of polished brass. More efficient than the Chapman Pump. Tenet hy in Chess 220) ost Aras AUN te eo ayes acon) Ales iba aA creek det a 43 53 For size ‘‘iron-pipe”’ thread, inches...................0 000000 cece eee B a e aC He sot A kts 98 depen tts Aug SUA, es PAR OG AO Sng A EERE el pal Saget eaten ene 4 1.45 1.60 1.80 5288. Filter Pump Couplings, of brass, with faucet thread for filter pumps. For size “‘iron-pipe”’ thread, inches............... 0.0.0.0 c eee cece eee t a! 3 ee a ee tae per aarti ECL ce eee age aaa ceaed ae tae mh TA eet ue ae AN .30 .30 .30 5289. Filter Pump Couplings, of brass, for connecting with faucet without thread. Cannot leak or be forced off. For size “‘iron-pipe”’ thread, inches............... 0.000000 cece eee eae i at a IB Hise sh se eee ES Te hors KEE 8) oe ae Ene Pad .50 50 50 5290. Filter Pump, or Aspirator, Geissler, of glass.............0 0.0000 eee 1.00 5292. Filter Pump, or Aspirator, Muencke, of glass, with one suction tube........................0., 1.75 5294. Filter Pump, or Aspirator, Muencke, of glass, with one suction tube and tube for connecting to manom- CURE ers he ies nis rd Bp alge a Le ANd oie at he ati e wa as RES OA A Suir casmoe ASeleaa nd aoe alata lacttnen Gum Doon 5296. Filter Pump, or Aspirator, Richards, of brass. A very powerful pump. The 13-inch size pump requires a special coupling as listed under No. 5297. The two 7-inch sizes can be used with couplings Nos. 5288 or 5289. Length, inches Bead cach arse ahs RARE HERO A UA OM Sem acy POR PES Ee Saree AREAS 7 i 13 For size ‘‘iron pipe” thread, inches... .......... 000.0 c eee eee 3 a 2 BAe A Te tao ol SA a erch tale aga en st Bee centre a dle ser 1.65 2.60 7.20 10% discount in carton containing 12. 5297. Filter Pump Coupling, of brass with faucet thread, extra large for use with Richards Filter Pnmp, ee size. For 3-inch “‘iron-pipe” thread Tarn M DISCHARGE. i (For description and prices, see following page.) 281 5301. 5302. 5303. 5304. 5310. 5311. 5312. 5314. oe SE Ua E.. TH 20 — MEALS CG -O;0 MPs Aco oN) ¥ Filter Pump, with vacuum gauge. On japanned iron base, with stopcocks for both water and air connec- GIONS estates Macnee aon wea are at ae tas Eats NR naire tga RENEE cana SOE ate a ere ee NEN oat ch 14.40 Filter Pump, Water Jet Form, displacing 3 cu. ft. of air per minute with 20-lb. water pressure. Will exhaust a 1-gallon vessel to a vacuum of 293 inches of mercury in 10 minutes with a 10-lb. water pressure and in 5 minutes with a 20-lb. water pressure. Very useful for filtrations, percolations and distillations in laboratory work. Complete with vacuum gauge, connecting tee and two stop- COC See oe acces tants fou an ech So PROS IAN WA el cop Marie che gl ce has EM a pete By Bs ne cecetnepe cae a 24.25 ditto, but for operating by steam instead of water; with steam connections. Has a displacement of approximately 4 cu. ft. of free air per minute and will exhaust a 1-gallon vessel to a vacuum of 24 inches in 7 seconds, with steam at 50-lb. pressure............-. 00sec ee ee eee eee ee 24.25 Filter Pump, with reservoir, giving both blast and suction. Consisting of a Filter Pump No. 5286 with reservoir 4 inches diameter by 8 inches high, with water gauge and stopcocks. All fittings are nickel plated. Reservoir is of enameled zinc. With a water pressure of 30 lbs., this device will operate two ordinary blast lamps. With metal bands for attachment to wall, as shown in illustra- GLOW esto eects eee oek, Ao ate eee er PR ey Prtals More Radian Anaad othe yA ahs. Saba daar seae Ursa ee Mh tae SESE NEN See 19.60 ditto, but with pressure gauge. With metal bands for attachment to wall, as shown in illustration. 27.60 Metal Band only, with holes to screw Nos. 5302 and 5303 Pumps to wall...................... 1.00 5310 5311 5312 5314 Filter Tubes, for filtering through asbestos, glass wool, glass powder, or filter paper pulp. With stem ;;-inch outside diameter. een gt h elne hesiasitst sca canwces sy eat ee ae eee roe PR ea ae eo ERR OS EONS NOR AE 6 8 Tnsider diameter in Chesites ie ays emnatoe hee neh piaea soho hake encase wane dteainti eee ened a anetebra sane 3 BR SACHA i ee ee eee Eetaceee nurs tes ocean Pee ar cra Orde Bart ale eee Nit ere ceenadeleo ris eynceya leo aan A 25 .30 10% discount in carton containing 12 Filter Tube, Pyrex Glass, approximate length 6 inches. Diameter of body,. inches... 4. 22054408) sid aengaae sam Teale 1 1} re 13 ROACH cess cia sf pcb n secon aor Ie oe a ae OEE Eat as nba mtn Geeks -40 45 .50 -65 Filter Tube, Fresenius, with bulb, 20 mm inside diameter at top 10% discount in carton containing 12. Filter Tubes, for use with Gooch, Alundum and similar crucibles. With stems ;-inch outside diameter. Tube of 28 mm diameter is suitable for Gooch Crucibles Nos. 4136 and 4135, 10 ml; 32 mm diameter for Gooch Crucibles No. 4136, 25 ml; No. 41385, 20 ml; and Caldwell Crucible No. 4144, 15 ml; 37 mm diameter for Gooch Crucibles No. 4135, 25 ml, and Caldwell Crucible No. 4144, 25 ml; while 40 mm diameter is suitable for Gooch Crucible Nos. 4136, 4135 and 4137, 35 ml, and Bitumen Crucible No. 1224. Rubber Tubing for making air-tight connection with Gooch Crucibles is listed under No. 8846. Inside diameter at top,mm.......... 18 20 25 28 32 OF 40 Le eee ee men tere! ce 15 20 2B 22 37 40 50 10% discount in carton containing 12. Prompt, accurate and economical service is much facilitated by the use of our original package | quantities, or even multiples thereof, in the preparation of order lists. These packages also increase | safety in shipment, convenience in unpacking and in checking invoices and safe storage on labora- | tory or store-room shelves. | In many instances shown throughout the catalogue a discount is allowed for these original pack- ages because of the economies effected in our own handling. Metric quantity specifications when | items are listed and packed on the dozen basis, and vice versa, result in unavoidable delay in shipment. bo oO bo A RT “oH UCR Fi... ay eS On EM As CO MP: A NY FLASKS Our stock of glass flasks for general laboratory use is now restricted to those of Pyrex and Nonsol glass, these two brands having in our laboratory tests and in the experience of our customers proven distinctly superior to all others. For a more detailed discussion of the physical properties of Pyrex glass, see page 71. 5324 -(\th actual size) 5324. Flasks, Pyrex Glass, with flat bottom and vial mouth. Capacityoml.: o2cec.ce3 ses 50 100 150 200 300 400 500 700 Takes stopper No........ 0 1 1 3 4 4 6 6 Bach. 3 os tass copa ce eee 17 18 .20 22 .25 27 .30 .36 10% discount in case of... 192 168 108 144 96 84 42 36 Capacity, ml............. 1000 1500 2000 3000 6000 12000 12000 24000 Takes stopper No......... 7 7 8 9 10 10 18 13 Hachinnd nacre oo eneas 43 51 .60 .76 1.60 3.30 3.30 6.60 10% discount in case of... 36 24 18 12 12 6 6 4 5326 —(ith actual size) 5328—(ith actual size) 5326. Flasks, Nonsol Glass, with flat bottom and vial mouth. These flasks are pear shaped rather than spherical. Capacity ml... 255 aan vp enicce wees oot 30 60 120 180 250 500 Takes stopper No............0--00 000200 0 1 2 3 4 5 Ba Cheeses an Rago ae EL ere oS 13 14 16 18 19 25 5% discount in case containing..........-- 144 144 360 288 144 144 Capacity; Msc. o. 0) settee Gira Reese eae 1000 2000 4000 8000 12000 Takes stopper NOs eaccad-slee vied a eee ee SS 6 9 9 12 12 Wee et eee an ee ee ie Ee EE ED .35 15 1.25 2.20 3.30 5%, discount in case containing.........----..++--- (2, 36 12 12 12 5328. Flasks, Pyrex Glass, with flat bottom and heavy ring neck, for use as Wash Bottles and in other work requiring rigid stoppering. Capacity, ml............ 500 700 1000 1500 2000 3000 6000 12000 12000 Takes stopper No....... 5 6 7 7 8 9 10 10 13 Wacht. 2:3 sheet se 38 47 05 -66 -78 -99 1.75 3.50 3.50 10% discount in case of.. 72 36 36 24 18 12 12 6 6 5329. Flasks, Pyrex Glass, with flat bottom and heavy ring neck, and with woven rattan covering over the entire length of the neck for protection of the hand from heat when used as Wash Bottles. Because of the remarkable mechanical strength of Pyrex glass, its resistance properties and the rattan covering, this combination makes the most satisfactory wash bottle obtainable. Capacity, ML... occa ches beer cen n nee eee een ssc ehp eb e a cerned eee nes een eS 500 1000 Takes Stopper NOs nn oui ue bone ER Se Rem eek een een bt BSC Hse o.oo cce haces eed ak Reon eau a eee eSomse rissa Stance audi ree nNaate ate ae das 1.38 1.55 Reo Re Pe) Ws aR H. Te UE OM ARS G30) Me PS A WN OY 5330— ith actual size) 5330. Flasks, eee Glass, with flat bottom and ring neck. Capacitysamls sow oki -yite irene Gneees Get okt ee wee tina, pen ecaan an nde auten Maeda mane odn 500 1000 MakeseStoppersN Oia econ svete s serps Matte, eee mera eer ce eam ecient cera ed aa 5 6 SAG e582) 4 as ale ratty Ree ewes Dap ices Sen EE aed Ved ee a er rent on apes tnond ventana aa that -28 38 5%; discount im case COntalning. .. =<, cs-0osctie Secs sare ok Pb ee OE ee 144 72 5332. Flasks, Pyrex Glass, with round bottom and vial mouth. Capacht ysl! contewiaawih shes Wis ain he Sede aie, 50 100 150 200 300 400 500 Takes stopper No..................-5. 4 4 Wa CMe) ie Poe! cee kena conn ames cel ene Gres 2 3 : s é 5 37 10% discount in case containing 48 Capacityscml 2 ccohcc it ea enh eraser cence eh oe es rar cu 3000 Takes: Sto pper2NGins e245 udu Sem Saale a wes BEA 10 1.07 12 5334—(ith actual size) 5336— (ith actual size) 5334. Flask, Pyrex Glass, with round bottom and long ring neck; 12,000 ml capacity; takesstopper No.11.. 3.75 10% discount in case containing 6 5336. Flasks, Pyrex Glass, so-called ‘‘Balloon”’ flasks, with round bottom and heavy ring neck. Capacity CCTs 5 ed wea scons A SND ahora es es nae etn matt wees a ha bane eR es ae ben A tea 22 50 Widthyvor bod yaMChes wey etn se eka eee horton Sr iat ai erate’ ww henna tao 133 18 Inside diameter of neck,-inches:.. 00.050. 66 Gck a bce bbe ba area ehh a eine Ane e 385 43 IAC HR cee i eae ect yee nee ars rN NR fe seeds wh yeee Mra he may rea 7.00 16.00 LOS, cdiscountrin::case: contain gs s.<.. 66. Gale Gace ma biegh secs evolu daehnan eee Reet 8 4 5338. Flask, Nitric Acid Balloon, Pyrex Glass, with round bottom and heavy ring neck. Width of ee 203 inches, inside diameter of neck approximately 4} inches, capacity 72 liters.............. 8.00 NotE—On special order Flasks No. 5336 and No. 5338 can be supplied with straight neck, 7. e., without welt. 284 A 5340. 5342. 5344, Re in ER H. T H O M A 5340— (gth actual size) Flasks, Pyrex Glass, with round bottom and short ring neck. see No. 5336 “Balloon” Flasks. For round bottom flasks of large capacity Capacity, ml. . .. 200 500 1000 1500 2000 3000 5000 12000 Takes stopper Noreen 3 6 8 9 10 10 11 11 Mache, eee eae ie -28 .38 .55 -66 .78 .99 1.40 3.50 10% discount in case of. . 144 72 36 24 18 12 6 6 5342—(4th actual size) Flasks, Erlenmeyer, Pyrex Glass, with vial mouth. Capacity; ml. 0505 46 dee ee 25 50 100 150 200 250 300 500 Takes stopper No............ 00 1 3 4 5 5 6 6 AGH ead oo ook eet ave anes 16 .16 -18 18 .20 ae 25 .29 10% discount in case of... . 360 276 180 252 144 132 132 12 Coca Mies aed ace ae 000 750 1000 1500 2000 3000 4000 6000 Takes stopper No........... 6 7 8 9 10 10 10 10 Bache: 66 wAvvancatn tee ens 31 .34 -42 51 .60 .79 1.00 1.60 10% discount in case of...... 60 48 36 24 24 15 12 6 ert th actual siz2) Flasks, Erlenmeyer, Nonsol Gee with vial mouth. Capacity, ml............ o6 120 180 250 350 500 700 1000 2000 Takes stopper No........... 1 3 3 4 4 4 5 6 8 Hachie, o60 ecauke Genes 14 .16 18 19 24 .25 Loe, 38 75 5% discountincasecontaining. 144 360 288 144 144 144 72 72 36 285 5346— (ith actual size) 5346. Flasks, Erlenmeyer, Pyrex Glass, with extra wide mouth. Capacity cin Pete: cow boren ys orate ies Seen teh) nesta Ss ky omnis 250 500 750 1000 2000 ‘Pakes'stoppermNos.cccc5 63k Dees ee AN tek Malet aaah 7 10 10 11 13 1 DEG eae er ee eh et eS ers eee Coe ee “22 .29 34 42 .60 10°% discount in case containing.................0.. 182 60 48 36 24 5348. Flasks, Erlenmeyer, with ground-in glass stopper. Capacity: ml ise se.eco ayes) bts wukinceen ies apecentona pee tere Osa mean wen ten te or 125 250 500 IACI esse vcoce eh onsen Sees gakcelts neces s bndeenin sunnier a aeennus 2 Sahai staat inch inte a ane Base 50 75 1.00 5350. Flasks, Erlenmeyer, Pyrex Glass, with ground-in stopper, flasks are of heavy glass as used in filtering flasks. Gapacitys Mle sure noes nec in ae Henn ei orendapelg laine dUptlers Suleealitptu woe ath oor wade tenets 250 500 1000 ACH sos et eae ee Nd oe Parties oa ke meet esa eal eee dey gece genoa he pee OF pe 1.10 1.35 1.80 js a : / SILICA SILICA 10 a \ é shi Pal ae Fa! | \ 32 \ 1%, ANT Co, 5356. Flasks, Transparent Silica, flat bottom, without stopper. © ape city, arin ee ee ee ey he etree Siro dea ADEN Lao ic bee Ostet OEE 25 50 100 ACH Be xtra oe tro hi hoeryn ee Nate gee aye Cam, naga ale itr eee Ge AL eek aa oS Ueyel ble g 4.25 5.75 7.50 5357. ditto, butrwithy-stopper ss .4 2 Luk ys ke a8 glee aentieius Gavia radiata Mama 11.75 13.25 15.00 5361. 5370. 5371. 5378. 5380. 5381. 5386. 5387. 5388. 5390. 5391. 5392. o> 5371 5370 5390, 5392 Flask, of polished copper, with ring neck. Capacity, ml..........-.....----- 500 1000 2000 Feiss beeches a a a den She ise ak tech HOS oO Ue Ray to eco es 2.65 3.20 4.50 Flask, of polished copper, as sometimes used for Kjeldahl determinations; 82 inches high, 4 inches diam- eter, capacity LOOUAML: sie t awe & te paws bead Pe bees eee a ace Be i ae Sit B 4.80 Flasks, Assay, tall form, without pourout. Capacity, ml..............---+5 150 175 250 Takes: stoppereNiOnwari cia vauewieawsseen Ab slde Miles ae pe eee es 7 8 8 PACH ees oi eceti ert eae ee ea een A ee Mia eb ay Ahatre es Cop ae Seen Aa REO eae 18 .20 22 10°; discount in case containing 72. Flasks, Assay, with lip and pourout,—a narrower form than No. 2139 Conical Beaker. Also sometimes 1 called ‘‘ Phillips Beaker.’’ Capacity, ml...........-... 5-005. s sere eee 25 250 500 Ae Pa oa ean a eee acre ee ee ae geek eared S @ pSe RAL ope suh Ren ag aDeNRS 13 17 .25 10°; discount in case containing...... 2.2.00. 2s 180 132 72 Flasks, Assay, with lip and pourout, so-called “Assay Beaker Flask.” The neck of this flask is not quite so constricted as No. 5371, nor is the lip quite so flaring. This vessel is well designed and has been found convenient for many laboratory purposes. Gapacity aml insecccod neu Gh Anis colts ee neh ets Ge Re actrep ak mete ae eran 250 500 Bey CIA ic ce sees caes ah she SC ERD ROM cath Diy paeane = Sth See eran ahi Ye aG 24 45 10°; discount in case containing....... 00... 60. e eee ees 72 72 1000 -60 36 Flask, Acetylization, with ground-in condensing tube; as used in determining menthol in oil of pepper- 1.50 TLE S OE Cin no: eect gh aioe ions te seen zyetscah wi Wea ar meant rg RRMA onde ascertain AMOR al Sa an eS Flask, Copper Determination, Pyrex Glass, with flaring neck. Capacity ails ..2c.nk Son pieminct ewes Mae eae Paty eA a ae AA 180 Tales SEOPPEL! Nl Orcsensyctepaieas 2 cotan sci ead worse eb weet eae are a ete cae aga Ga aR 5 Ba CB ea prey a Sn eta ag atioe ht snd BA Teetnea atecea ae rei Taleo ade seh ett Bc .25 10% discount in case containing.......... 0.0.05. eee eee eens 144 ditto, but of Nonsol glass. Each... ........... 0000.0 e eee enters .20 5° discount in case containing............. 60.0.6 e eee ee eee teens 288 Flasks, Dewar, Vacuum, tube form, for liquid air. Without base and unsilvered. Taength, outside MM. 4). .c5i- cece Ads eR ee es aA aR eames Ee a 100 Outside diameter, MM........... 0.0 eee ee eee ees 45 Tnsidesdiameten; MMs veins s fone oe oa a abr eee eae wee PEO ET EA ME Merete 30 Boa CHS oe demesne EAN, Gone Weegee Gad Petit ons MER Sa en ee 3.00 ditto; butesikvered.s .Avvone a1 cationcis oc tasks ete he aire hares Mane a Goren Ae Ue 3.50 250 6 30 108 24 144 250 60 40 5.50 6.10 Supports for Vacuum Flasks, of polished wood. These are convenient to use with vacuum flasks, as they obviate largely the danger of breaking off the sealing point at the bottom of the flask. To fit: HASH MIM = cere ois 4 GALEN et) Se Ga naar ie cen eng, Roma NNR 100 250 Bea Haass ects ase daa a ais eigen see tee oz etd aaa ae Tee osama at ES GND en 1.25 1.25 Flasks, Dewar, Vacuum, pear shaped, for liquid air. Without base and unsilvered. Capacity ml: 4 gree. asescetcs onan ated RRO ya Agree os 125 250 500 Baise ech ick ok os eas Lh SE gE Rett ME EM Joe a nea oda ac cel eo 4.00 5.00 8.60 ditto, but silvered.. 0.6.0.0. c cece eet tenes 5.00 6.00 9.90 Supports for Vacuum Flasks, of polished wood. These are convenient to use with vacuum flasks, as they obviate largely the danger of breaking off the sealing point at the bottom of the flask. i MO: Tite Has ken dal ges wre aac svnshk eevee sunt eRe oe edie b EAGR Ie RS eat encom Geeta 25 250 500 Bag GH kes ess caer Sass 02 ae aaa ena «ay ent eae au sence ant ia oa eae 1.00 1.50 1.50 53896—(ith actual size) 5396. Flasks, Distillation, Pyrex Glass, with side tube at center of neck. The 200-ml size is made in exact accord- ance with specifications of the Barrett Manufacturing Company. See Methods of Analysis used in Coal Tar Industry, Journal of Industrial and Engineering Chemistry, 10: 9, 10, 11 and 12. Capacity.mll scents ae es el ee A 25 50 100 125 200 250 300 Takes stopper No................. 1 1 1 2 3 3 4 IEA GH Sarat col eA were resi emer -36 .40 45 5) 55 -60 -65 10% discount in case containing. ... 84 60 54 48 54 24 36 Capacity mle th itent ee cae eee eS 500 700 1000 1500 2000 3000 Takes stopper No................00 0.0000. 4 6 6 7 9 10 a Cli vn25)) eects, Sent istics meenonpagtnttinwn lhe wens .70 1.00 1.18 1.45 1.60 2.15 10% discount in case containing............ 21 15 12 9 6 6 if \ | ENGLER Wy ENcLeRt AMT.CH. 5398—(ath actual size) 5398. Flasks, Distillation, Engler, Pyrex Glass. The 100-ml flask is in exact accordance with specifications of U.S. Bureau of Mines Technical Paper No. 166, Motor Gasoline, Properties, Laboratory Methods of Testing and Practical Specifications, by E. W. Dean. The 250-ml flask is in exact accordance with specifications of A. 8. T. M., Standard Specifications for Distillation of Bituminous Materials Suit- able for Road Treatment, 1918 Revision. Gapaeity camel yata ms ciate tna: sess ee ceched date, We A Nan WA eps yee earths te ee Ee 100 200 250 nae 2 2 -70 48 5400 —(4th actual size) 5400. Flasks, Distillation, Nonsol Glass, with side tube at center of neck. Capacitys cml sce s ie inet dicen vos oe Cay sckts ee wel winded nha be 120 250 500 1000 Each ...... RSC eR Ste eS Bae SR tea Ne fre eee oes er len hear aaa 54 -60 .80 -95 5% discount in case containing............................. 12 36 36 24 5402. 5403. 5406. 5410. 5411. 5412. 5413. 5414, 5410, 5411 Flasks, Distillation, Ladenburg, Pyrex Glass, with three bulbs in neck, 500 ml.................. 2.00 Flask, Distillation, Hempel, Pyrex Glass, with side tube bent at end. Capacity 500 ml......... 1.50 ’ Flask, Creosote, Pyrex Glass, with tubulation and constriction. Capacity, 500 ml.............. 1.75 Flasks, Distillation, Claisen, with two tubulations. Capacity mle. eats cnet oe inact ane nuttin leaves mid Be eens 50 100 250 500 75 1.00 1.25 1.50 ditto, but of Pyrex Glass. Capacitive. Mal ees reed erntace a) a peat paseo cote itn iteion anaes 125 250 500 1000 ACH rac eran shee er ne ae eg ere OS intone EY AI Catia an 1.60 1.80 2.20 3.00 Flask, Distillation, Pyrex Glass, with side tube bent down at right angle. So-called ‘‘sulphur” flask. Takes No. 5 rubber stopper. Capacity, 500 ml........000000.0.0. 0.0 ccc cece eee eee 75 10% discount in case containing 40. Flasks, Distillation, Transparent Silica; with round bottom. WA PACltys Simla csikete creel 8 is a ado evans arin wind ome ain vA eee eee atoms amu 25 50 100 VCH yy tase teat sel ae ese seh cent stiseet mes eines ealseen nad ramen Dan WR cate sae ed et teh ut cet ol 6.75 8.25 10.00 Flask, Distillation, Pyrex Glass, with ground-in side tube and connecting bulb; for ammonia nitrogen distillations in water analysis. Capacity, 2000 ml................. 00.0. e cece eee 5.30 We list and sell many articles under the manufacturer’s name and, while these manufacturers are primarily responsible for the design and performance of their product, we take full responsibility —having exercised no little discrimination in our selection—for all such trade-marked or branded items in this catalogue. 289 4955 5420 5422 4950 5424 4960 4955. Flasks, Extraction, Pyrex Glass, with flat bottom, wide neck and vial mouth. Capacity, ml.......... 50 100 150 250 500 750 1000 2000 3000 Takes stopper No...... 6 6 7 8 10 10 11 13 Bia Chic e5 ott azo eee -16 18 19 -20 .29 .36 54 .98 1.40 10% discount in case of 168 120 108 120 60 48 36 18 12 4962. ditto, but of Nonsol Glass. Ga paicitiy sein lhe nas A yacte. toa tar Fe eens an OA Bie De enh Manes Nie He ren NS 120 195 250 350 Takes stopper No............... Aas net ete Wt Rath eee s ; 7 7 9 9 Bachiics ye ears eck ee ENC Seria als & eile Poet See ee ve sok 25 -28 30 5% discount in cases containing................000.000 00. ee .. 860 288 144 72 5420. Flask, Extraction, Pyrex Glass, conical, for mercury seal. Capa cityecrials esate sastheed se Nettie Secale dace erage aac s Rtas Rete Ry ee : 100 150 250 Bachiveshorws tots doen ho Gage ez aoe ole eis Dah tee aby Dosen teed de 200 2.25 2.50 5422. Flask, Extraction, Cottle, as used in No. 5014 Cottle Extraction Apparatus. Capacity, 350 ml, diameter Olen ected Onin s ince aes te tuck tect e Deke ec ex ea aay thie cA Miata ee ag PLR Mei wed Sate .60 4950. ‘Flask, Extraction, Knorr, for mercury seal, with #;-inch hole in neck above shoulder of flask. Capacity, OST pas eager ete inte che AN cote Mat ets ap tit OEM Memoe rue, tn Onee alah he We brioche Ala t, wine Py An a8 dae 50 10% discount in carton containing 12 4952. Flask, Extraction, Knorr, with two 6-mm holes opposite each other in the neck to provide for the return Hlow-olethen:. «Capacity, lOO cmilwac a ase thts enlist ells aie huis mt aya ted eal Miata eect cme coe 70 10% discount in carton containing 12. 5424. Flask, Extraction, J. R. J. C., Pyrex Glass, as used in No. 5016 Extraction Apparatus according to Joint Rubber Insulation Committee specifications. Capacity, 400 ml. Takesrubber stopper No.9 .32 10% discount in case containing 72. 4960. Flasks, Extraction, Sy, with two holes in neck and trough for mercury seal, with large neck to facilitate cleaning. @apacitycml: 25 moctwsaey po taoitassaals are Ree we ok Soe 100 150 200 250 850 Wa Clings eteieyektatesth nee thn ius Mn enh ociians buena ph ate ses -60 -80 -90 1.00 1.15 5428 5426. Flasks, Filtering, without tubulation, of heavy glass to withstand moderate pressure. Capacitysomles ton bis ten tet ca teers okt eet Wu a ee buen he 250 500 1000 2000 Makes:stopper! NOs earch ics, Seater ar wae cen oavhy evra eee wea 5 ci © 9 Bic teu eenaarern: Bae ne ater mae eae, nae 20 30 40 65 10% discount in case containing............................ 96 60 24 16 5428. Flasks, Filtering, Pyrex Glass, without tubulation. Of heavy glass to withstand pressure. Particularly recommended because of the great mechanical strength of Pyrex glass. Capacity Me ac ate alike ecu tis i Nery halen paehe eae ie 250 500 1000 2000 4000 MAKES SLOPDED INGOs 4.52 cc wcys emis meonemn Soe eee 6 6 7 9 9 Bach jo cncsce:s ct bwrie SA RST A Seeeaal Anahi tye cae uaa Cay ea a -40 54 84 1.20 2.00 10% discount in case containing.................... 120 72 30 30 9 5430. 5431. 5432. 5436. 5438. 5440. 5431 5438 5440 Flasks, Filtering, with side tubulation, of heavy glass to withstand moderate pressure. Capacity; Mller. wey cat ese ea ye Saeed eae es 250 500 1000 2000 4000 Takes:stopper NOsian scene eteone ened eae 5 qT ris 8 8 POA CHR ce hese Sea ae a td ade Rt econ peck Mane ge GSE .50 .70 1.00 2.00 2.60 10% discount in case containing..............---+-. 96 60 24 15 6 ditto, but of Pyrex Glass. Capacity; Ml eis tacs tae idiharne: 4s Same In es 250 500 1000 2000 4000 Takes:stopper NO: 9.44.44) fe dee eee eee ns 6 6 7 9 9 THRE eee serena mtr ye 70 95 145 240 4.00 10% discount in case containing............-....-+: 96 60 24 15 6 Flasks, Filtering, with side tubulation and glass stopcock; of heavy glass to withstand moderate pressure. Capacity; Mleccs ccna aan mete ee eens aetna gle aeet carte ean goog a 250 500 1000 Takes: stopper No... .....¢+00e8 bene sete ed eee ea ae eee ea ape 6 4 iG Ba CHa oe ean oan Sa ce ins asks fea oraae a Rip annaaateca eeaiee Sy 2.00 2.25 3.00 Flasks, Filtering, with side tubulation and funnel ground into neck. Of heavy glass to withstand moderate pressure. Capacity) ml)... h:i.ssa wets s aaah tee ek oak Nera aah ee be eet Paes 500 1000 BEA GI eg et ected 2 eae ys FA oe edt nen etre eee REARS 2.40 3.00 Flask, Filtering, Shaw. This flask is similar to a pear-shaped separatory funnel with a side outlet tube for the suction, and a wide neck for taking filter funnel fitted in a No. 5 rubber stopper. Bulb is 400-ml capacity. Convenient for a great variety of analytical work, as described in Journal of Industrial and Engineering Chemistry, August, 1917, A New Filter Flask, by Jos. A. Shaw.. 5.50 Flasks, Iodine, with wide, flaring, funnel-shaped lip, and hollow ground-in stopper. Capacity, ml. 0.0.0.0... cee cee een enn center ees 125 250 500 Rig clic ety se) deers ce Ipcie Hee RE ta ies aN Aet Sateen do ted 65 85 1.10 10% discount in case containing. ....... 2.66.6. 6 eee rete eee 48 36 24 5443— (ith actual size) §442—(ith actual size’ 5442. Flasks, Kjeldahl, Pyrex Glass, with round bottom and long neck. Capacityy alien sorst sovrae eaie ea eyines eer Meh eto niet Mapawner ey meen 300 500 650 800 Takes stopper: NO seq ewe noes hg Garis PUM AER a Sepa Do 5 6 6 6 Approximate length over all, inches..............+-++++-55 ae: 11? 123 123 143 AC a acs rge erste ote ao SNES AAD ons usmle eT A ee ee eR RS .28 37 42 45 10% discount in case containing..............0 0000 eee eee ee 60 36 36 36 5443. Flasks, Kjeldahl, Nonsol Glass, with round bottom and long neck. Gapa city sac weet oko Gl han a Meroe BR hen ote ech eae NG aca ne ey aN chums pat inate tage eee Re 500 800 Phelehtccraimisa ase ay eto esctene st chats Se ras MEER One ee Oecd Row alee hig aa tsa Ca ates tres 320 360 Diameter-of. bodysmMiic x3 cect sens Sb De Ae cp ee ok tere 100 110 TPAKESESCOPDET ING ced 5 ceeh na OU sel SM aes dikes eis ERR es SIR aE LEI Sch re tits eee ARE i it 6 7 BH Sos ene ee ae cera tye cE ONES lees eis EEE ras Ste ase attcoaes ee eR .38 44 5% discount in case containing 36. 5444—(ath actual size) 5444. Flasks, Kjeldahl, Pyrex Glass, with round bottom and short neck. Capacityscmlit gu. t.ccan nie ncmMa ee ce ethernet neers rig hee ote, 0 MPalkeesustopper NO sd. ead chennai pees Eon tw ok Ge ge ae 8 Approximate length over all, inches................................. i ie 11 aC has eters a oe Meese | Mees alee ee ne te WA gn ee ee “28 ~«87.—~—t«‘<‘CCS 10% discount in case containing.................................... 80 “48 ‘36 5446. Flasks, Kjeldahl, Pyrex Glass, with flat bottom and long neck. SA DACIE Vala ns mites ine toocd enemas Aa 5m een egh coat ec th gOS E Na 300 500 Takesistopper IN Osc cated casey eee fac HEMI ARCR Rene te ee ee een gent ey aka eek 5 6 Approximate:length-over ‘all; Inches: veg <5 24 acescsg gcceg th vied ote hen ok ann acne 2 108 125 ACHR FS ie eter Vane nected dee ett AR aa cee gels 28 37 10 %discountinycasé- containing cgi ec oman een ee ee 60 36 5456 5448 5450 5448. Flask, Moisture, Pyrex Glass, for use with’ Brown-Duvel Moisture Tester, as described in Circular 72 of U.S. Bureau of Plant Industry. Takesa No. 5 rubber stopper, No. 8821. Capacity, 1000 ml. 1.50 10% discount in case containing 36. 5450. Flask, Moisture, of polished copper with double wall, for use with Brown-Duvel Moisture Tester in place of the glass flask. See Circular 56 of the U. S. Bureau of Plant Industry. ................. 9.60 5452. Flasks, Soil, Pyrex Glass, with long condenser tube ground in neck of flask. The 300-ml size is also recommended for the determination of formic acid by the quantitative method for the precipita- tion of the mercurous chloride. Capacity amas hts, os orinecs meen cattincmaen Gea Wad Soa ad aa ett ee 200 300 500 Ee CHa eee tes ee tay pe eet Ap Ree ate teh eR Rt ae eG Deh a Ngee Se Ra are 2.25 2.50 2.75 5454. Flask, Sulphur, Johnson, Nonsol Glass. In exact accordance with the author’s specifications. With heavy ring neck taking a No. 6 rubber stopper. Capacity to base of neck, 275 ml, height 165 URI N asedeses aoeeee coher, Fea A STL ah cst, Eh ou ois one pipdebeeab SB aarass Tae roe Ea RON donee re PLG Io et pest in ON cao ae 38 5% discount in case containing 144. 5456. Flask, Sulphur, Johnson, Pyrex Glass. With heavy ring neck taking a No. 6 rubber stopper. Capacity to-base:of neck; .275 mil, height V65 mines. 5 mcs 25a so ok ce Sie eovca erases clon une Snake ecuisnen bee 32 10% discount in case containing 108. VOLUMETRIC FLASKS All of our flasks, unless otherwise specified, are graduated on the basis of the true or metric liter, which is the volume occupied by a quantity of pure water at 4° C, having a mass of one kilogram, and upon the one-thou- sandth part of the liter or milliliter (ml). With a few exceptions, the true or metric liter is now accepted as the standard in all analytical work. The volume is adjusted for a temperature of 20° C. At the request of the Bureau of Standards, we are discontinuing the use of the term cubic centimeter (cc) by which the one-thousandth part of the liter has heretofore been designated in both trade and laboratory ice. Eo Our volumetric flasks have been recently redesigned as to shape and dimensions and we endeavor by fre- quent control to keep the limit of error in the total capacity within the tolerances shown in the following table, which, in our judgment, seem reasonable for routine use: Capacity less than and including: Limit of error + (to contain): Hi Otrii l eeteneeee Merl eA ese eRe, Be eet ara ee A 0.06 ml D immed sch excuteasahak ne 6 Soe ae ee eae Bree Pee .06 ml BOs ses coomeci a eee hifcths dese gman eae, Aias oak Oem MO Ostia er ces coer ees Os eae hs Alaris exon entation, ~cekGuml D200 Malate eos eres ccna esau eee meee eee CoOL PHO rsinais sretciaes & ouraeion eat toenueemeaer cs amet. acer) 500 ml........ ced daae ete erie hte tien hatte. OSIM NOOO sale boot ea ded cere end enacmeae manhergeesl, oe GOLIML 2000: Me ae keene samara geen Ausee Boiion salbin mtn acel 1.06 ml Our listing of Volumetric Flasks occurs on the two following pages. Certified Volumetric Flasks are listed on page 296, and Sugar Flasks on pages 297 and 298. 293 SNIV LOD 5460, 5462—(!th actual size) SNIVLNOD 5461, 5463—(:th actual size) 5460. Flasks, Volumetric, without stoppers. To: contains ML 5.3.0. dikaneerseeet neers 10 25 50 4100 200 250 500 1000 # 2000 a Clie sneyn sar Ac omen sine ee tink eel noe 30 «© .40 = 45 48 50 55 .70 .90 1.40 10°% discount in cartons containing... 24 24 24 60 48 48 36 24 12 5461. ditto, but with ground-glass stoppers. To-contains Mls. sks nets 10 25 50 100 200 250 300 500 1000 2000 WA Clie hen, cle fcc ar RS oe 40 55 65 .70 .75 80) .85 1.00 1.20 1.80 10% discount in cartons containing... 24 24 24 60 48 48 36 36 24 12 5462. Flasks, Volumetric, Pyrex Glass, without stopper. "BO COnEAIMG TM ck Soe Sn soa ee are eee le ee ae: 100 250 500 1000 2000 WA Chie ga iecats be iey hn Sara uty eae ened ane Eee ns orech he 1.00 1.25 1.50 2.00 2.50 10% discount in case containing.................... 144 108 60 30 24 5463. ditto, but with solid Pyrex glass stopper. Bla Cli ise aresert iioe arse tana Renee ake mean ey teehee 1.60 2.00 2.40 2.80 3.60 10% discount in case containing.................... 144 108 60 30 24 5464—(ith actual size) SNivLMNOD] | SeSANIG YLNOO) |Seaninga su 500 m1 at2a’¢ 5465—({th actual size) 5464. Flasks, Volumetric, with ground-glass stopper and blue stripe on white enameled background for accurate reading of the meniscus. SP OrCONbAI, NM lore siid on ip oes oder ee oy Be a Gane ues ee anne ane eae 100 250 500 1000 Pacha ewete emesis Aer er ERLE nee) 1.00. 120 1.60 2.10 10% discount in carton containing......................0.0. 60 48 36 24 5465. Flasks, Volumetric, with ground-glass stopper. Graduated to contain and deliver. Capacity; Mlle nc cea al dent aus G tat eae acoso ayed autores 100 250 500 1000 Bach) ax Rene eran ee ine eee 30 1.00 1.20 1.40 10% discount in carton containing.......................4.. 60 48 36 24 1000 ml at 20°C 250 1 j ae | f / \ 5466, 5467—(:th actual size) 5468—(‘th actual size) 5466. Flasks, Volumetric, without stopper and without graduation, 7. e,, for calibration in the laboratory. Capacity}. ml: os is:254 cy snare hans nee Wane eee Gry Lat stear anes mene ae : 100 250 500 1000 DAC rah etd eet ee ees CeO hry are ese by Sie OR cccanges ta abet ate hey .30 .35 .50 -60 10¢% discount in carton containing...............0....000 220+ 60 48 36 24 5467. Flasks, Volumetric, Pyrex Glass, without glass stopper and without graduation, 7. e., for calibration in the laboratory. Gapacity sms Arete hectic ya tenetad can Riese ee ceo . 100 250 500 1000 2000 Bia cht: a jester ec ane eee ee Be ea ey es 44 -60 -80 1.10 1.45 10% discount in case containing.......... any ieee hep 144 72 48 30 24 5468. Flasks, Volumetric, with ground glass stopper but without graduation, 7. e., for calibration in the labora- tory. Gapacitysumnls a ar eyk Are ike eens hg ete aeus Le A . 100 250 500 1000 Hach. 2232s ecg as eere Seea re cb hal asa unt Soak Eien, CE etearas Bach : 50 .60 75 -90 10% discount in carton containing........................ : 60 48 36 24 NO.43 CONTAINS NO.43 CONTAINS \ 900 \ 500 \ ml \ Bie ml at20°c | at20°C At 20°C es AH.T.CO AH.T.COo 5469 5470 5471 5469. Flasks, Volumetric, Giles, with glass stopper and two graduations. When used for making norma solu- tions the 10% extra volume in the neck is used for ascertaining exact titration, leaving a volume equal to the exact capacity of flask for correction. Capacity; Mle cus. wcce se ae 500 and 50 1000 and 100 2000 and 200 Pach). a3 cask kes Bees Diba snckiapameee ats 1.80 2.60 4.00 10% discount in case containing............ 36 24 12 5470. Flasks, Volumetric, with ground-glass stopper and bulb in neck above graduation. Capacity of the bulb approximately one-tenth the graduated capacity of the flask. As suggested by the Com- mittee on Standardization of Laboratory Apparatus, of the Manufacturing Chemists Association of the U. S. Po: contain | ree 5524 Veal ote sickest ale eal 5510 5511 5532 5510. Flasks, Sugar, with two graduations, providing for {> dilution as used in inversion methods. Capacity sili. Aan tac sence Vora water nee nme an nen cee 50 and 55 100 and 110 200 and 220 ROVER AT Ces stan hes sea eilie mee be toda: seinoel db oper peed Sule eile -03 -05 .10 Ba ehiy seij accra etary) a matin eons ee ie eo eg Ber cones een aape tah oe entaies .40 -60 -70 5511. ditto, but with volume adjusted at 27.5° C, for use in the tropics. Capacity, MMMM stare LONER kane Con rat Bere ieee hearty Cortese ECR Aen oe 50 and 55 100 and 110 200 and 220 Tolerance; Emil, ics. Sis hiner ls ke ee Aes -03 05 .10 RC Re in pe aes a PR csc ae net iae tier rege a See -40 -60 -70 5512. Flasks, Sugar, Pyrex Glass, with two graduations. Capacity. amen cas ond a len ec Bes UU ae ey acorn at ae REY ena ete ANA Aaa ts 100 and 110 200 and 220 Cals ee ee lec eee bas hed Ganon tae te dayne I cand ce as Suter guse rata tae 1.10 1.25 10% discount in case containing 144. VOLUMETRIC FLASKS FOR SPECIFIC PURPOSES. These are all designed and made for the use indicated in the description and are within the tolerances as given on page 293 for our regular volumetric flasks, with the exception of Viscosimeter Flasks No. 5536 and 5537, which are within the tolerances given on page 296 for certified flasks. 5520. Flask, Alkalinity, as used in determining alkali in the analysis of feed water for boilers. Graduated to COMET OF SEMIN wee ay mer fete ie earth etek rire Ren iat ony aah tees Oa tea enh ap ve ae a eN a, URN Ria -60 5522. Flask, Cassia, with graduated neck and glass stopper. Capacity to bottom of neck 120 ml, neck oe ated: to=lO-ril im ese aces ot Sheen d coaster eet ey whe Ghee Rt ty ad see Man cI eee ae Dk Ae a ol AEA why .80 5524. Flask, Fertilizer, with short neck; of heavier glass than the regular volumetric flask, and with mark low on mecks. “Capacity s200) Mls. iibec i pe PhS clei coh wee he deacschs der mhescedipeh punts oe chee A cuieend ene niceuaeR matatlne ob -90 10% discount in carton containing 72. 5525. Flask, Lactose, identical in shape and dimensions with the Bates sugar flask listed on page 297, but with volume adjusted at 102.6 ml at 20° C, for the determination of lactose in milk by the polariscopic method as specified by the Association of Official Agricultural Chemists in the 1920 edition of “Official and Tentative Methods of Analysis” 1.10 5526. Flask, Phosphoric Acid, for determination of insoluble phosphoric acid, particularly in fertilizer analysis. heavy glass to withstand violent shaking, and with 200-ml mark low on neck. As originally used i in Massachusetts Agricultural Experiment Station .80 10% discount in carton containing 12. 20% discount in case containing 72. 5528. Flask, Phosphoric Acid, Pyrex Glass, With wide neck. Capacity, 200 ml...................... 99 0% discount in case containing 108. 5532. Flask, Saponification, with graduations above and below the bulb. For saponification method of deter- mining total fatty acid in cottonseed and similar products. Capacity of bulb, 250 ml....... 1.80 5534. Flask, Saybolt Viscosimeter, Pyrex Glass, with large hemispherical lip. Capacity, 60 ml.......... 1.25 5536. Flasks, ee nreet, Certified, as regularly supplied with Engler Viscosimeters. With unofficial cer- tificate. @apacityewm lanes 0 acheter tere ie ee EA ASR AM AE 100 200 aC ess oe etree ey a et Neete Ee TL wa ae end ee exh tay iN AA Nc er ie een etnies Aer 1.95 2.50 5537. ditto, but tested by the Bureau of Standards and engraved with official mark of certification. i tye nls seen ethane a et toda tea mee oe Cena en eer nee 100 200 ea CTA ger re nce sce ah eect a Oat gt rei vet oun eth ae mac yee Pe Re en 3.00 3.50 5548. 5549. 5550. 5551. 5554. 5555. 5556. 5557. 5558. Le en 5554 5548 5549 5550 5551 5552 5542 Flask Heater, heated by incandescent electric lamp. Convenient for conducting ether or similar dis- tillations without danger. Price includes tripod and 60-watt, 110-volt carbon filament lamp, con- necting cord and plug. Takes a 1000-ml round bottom flask. Without flask............. 12.00 Flask Heaters, of sheet iron, with ventilating openings and asbestos inset. Diameter: NIMs acy. a 5 aes pes Rs hoes Barisal Honad be alg hen eee 110 130 180 220 270 CMs eer ed At DU sO a rc Ea GO a .64 1.04 1.20 1.36 1.60 Forceps; of brass; straighti<2 vy ae oe i ee ee oh ete eS id es Rey 35 10% discount in carton containing 12. 20% discount in carton containing 144. Forceps, of brass, bent...............-......25. poeaneeinee Lateohes aaa Herein et bac aa 35 10% discount in carton containing 12. 20% discount in carton containing 144. Forceps, of brass, with ivory tips.......--.......-.. eee eee Prone tan ee BR ne Cont reat a 1.35 10% discount in carton containing 12. 20% discount in carton containing 144. Forceps, of steel, plain, so-called ‘Button Pliers.” Teen elimi ocr auttrece ssecors: bt sere RS Rees pads aang ee hare ee 100 112 125 150 hee tee eet eon ee eee rrr 14 17 .18 .20 10% discount in carton containing 12. 20% discount in carton containing 144. Forceps, with glass tips. Recommended for lifting crucibles, crucible lids, pieces of glass, etc., out of strong acid or alkaline solutions without contamination. The handle is of nickel; 62 inches total Peri Gb Hisinc esate nc bits ear a een eeu Mee heehee pe ga vera en erat enc dera sites eaady aun Ann ne ma Rts 1.50 Forceps, Specimen, of steel, nickel plated. For removing specimens from deep jars or bottles. Teen pt enna evans arc cer eo. a tached ty Dn mantener bp ios canes ets 250 300 375 450 Blt: es eh ee ee Ba EL ed os Sonate 2.00 2.50 3.30 4.00 peerce. DHMH 5555 a ny B —- TTT WA = in 5556 5558 Forceps, Cover Glass, with flat, bent blades, 105 mm long.........................0.-.0.005. 1.00 10% discount in cartons containing 12. Forceps Cover Glass, with thin, straight blades and guide pin, 115 mm long.................... 65 10% discount in cartons containing 12. Forceps, Cover Glass, with thin, bent, flat blades, self-closing, 125 mm long.................... 1.20 10% discount in cartons containing 12. Forceps, Cover Glass, Ehrlich, with long, flat blades and locking device, 135 mm long............ 1.25 10% discount in cartons containing 12. 299 5559. 5560. 5561. 5562. 5563. 5564. 5566. 5570. % Funnels, Glass, with an exact angle of 60°, with stem ground to point and with ground rim. 5 21 i, } y 5560 Forceps, Cover Glass, Novy, with flat lower blade and curved, pointed upper blade. Nickel plated, 115 AMATI OW Oy spacre weoted ate vatitel Naat yon aetna eel toa og Me Me a La gs geet a Ue GY bec nts ped MR NRC clan ee 1.00 10% discount in cartons containing 12. ditto, but with locking devices i260 .es pea dca mecidd atu Bh aie a sh oh thes ep aullae HG atte anita, Soba naee % 1.50 10% discount in cartons containing 12. Forceps, Cover Glass, Cornet, of spring brass, nickel plated, self-closing, 120 mm long........... 50 10% discount in cartons containing 12. 20% discount in cartons containing 144. Forceps, Cover Glass, Stewart, original form, of nickeled spring wire, self-closing................ .20 10% discount in cartons containing 12. 20% discount in cartons containing 144. Forceps: Slide; Kirk brid @3c) coe & sxe es lan ee Se lh SR AM oie eerie eel we Aedes ee ely Sony, -10 10% discount in cartons containing 12. 20% discount in cartons containing 144. Forceps, Slidé,: Bostons.c.\ 424, saci deere alent eas eee cet ee Vem Cree eke eek .70 10% discount in cartons containing 12. 20% discount in cartons containing 144. Forceps, Slide, for convenient handling of slides; as used in Frost’s Little Plate Counting Method.. 2.00 FUNNELS 5570 Sie Diameter, inches................. 1 13 1 : 33 4 Length of stem, inches............ 1% 13 21 oe 31 34 2 Each...... Mis Aire ewes ces My Srasiy Geb ee 15 15 .20 .30 35 .35 40 20% discount in case containing.. .... 144 144 144 144 144 144 72 Diameter, inches................. 5 6 7 8 9 10 12 Length of stem, inches............ 5 5h 6 6 Ts 83 t Each Tyne cer yaaring awiaee una oragate Want -60 70 =| 1.00 [ 1.10 2.00 1.85 3.00 20% discount in case containing....... 72 72 \ 2A 12 12 9 4 tee) 300 a 5572 5572. Funnels, Glass, with an exact angle of 60°, with long, thin stems ground to point and with ground rim. Diameter, AmMCHeS omy s eck are asersne a atieos Uepsenenk nine sabe 1 13 oe Gength-of stem; inches «02:00 ines ere ase eh el 3 3 4 4 4 aC ea ee et eh hae a eps ihigas haat yaa eM aad ten Cae es nae 24 -26 .30 -40 20% discount in case containing...................... 144 144 144 144 144 Diameter inchess 6.5550. fe ee ee he ectoe po See eee tes : 4 4 43 43 6 Length of stem, inches.................00. 000000 ee 4 41 43 54 53 aCe eon oh ees NA ee nares ae Rea ard irae goons Ar Re 45 -50 55 -60 .70 20% discount in case containing...................... 144 72 72 48 36 5577 5574 5574. Funnels, Glass, with an exact angle of 60°, with extra long, thin stems of small bore. Diametersinchese 5a cis ers oss eae teen wane 2 23 3 33 4 Length of stem; Inches 2.442 .c-2c hint mene gids 6 6 6 6 6 BACH ee Lae edt td rn ay eee Se -28 .30 .35 .40 45 20% discount in case containing.................... 144 144 144 72 72 5577. Funnels, Glass, with short wide stem, so-called “ powder funnels”. Diameters hehe sect ote dtc ious nance ow Gage o tena Lat SA nemitate iene 60 80 100 Diameter of stem,mm.....................0005. Dest ehet anid pk eaemcene 14 16 18 BACH eee Sees en As Sok ac ah ald Sze ree th rch Nera .20 .25 .30 5578. Funnels, Stemless, of glass, as used in sugar laboratories for filtering solutions for polarizations. Capacitye Tl: onct.cesay tastes es aac rear ae arr OG onde easel in ena sheets 100 150 225 Diameter mete tet enye cars ee arcteen eens Seca era gn hone wets pe tc ree aes 70 90 ~_—=—«'100 Be a ere ae eae age rca cath uct eect Pe NEE NY ek Cet oeh RR Raley coche ghee .25 .30 .35 10% discount in carton containing 36. 5579. Funnel, Victor-Meyer, to suspend over evaporating dishes, 200 mm diameter.................. 2.00 5580. Funnel, Stemless, of fluted copper, as used in sugar laboratories. Diameter, 4 inches........... 1.00 5581. Funnel, Stemless, of perforated metal, as used in sugar laboratories. Diameter, 4 inches........ 2.00 5582, Funnel, Sugar, of German silver, for transferring sugar samples, 4 inches diameter and with inner diameter of stem sufficiently large to allow free passage of sugar into the flask, and with outer diameter to correctly fit the neck of No. 5500 Sugar Flask, 100-ml size...............0. 00 cess eee 6.00 301 5587 5588 5584 5584. Funnels, Ribbed, for quick filtering. Of heavy pressed glass with finished rim. Diameter, inches 23 33 43 5? Tt 8F 10} 13 Wahine es aan es Aske 22 28 32 48 67 1.25 1.85 3.45 5585. Funnels, Glass, with diagonal fluting, for very rapid filtering. Particularly recommended for use with special filter paper No. 5250 in filtering agar for culture media. Dia Meter MMs occ anys ike sed hemloeened wae 70 100 160 200 240 aCH Makes 1 Ges, cuacirh Aan enna cee te aairnenen Gi nraaiedey evan -30 -60 -80 1.25 2.60 5586. Funnels, Glass, set of three for delivering minute quantities; 7,1 and1}-inch diameter. Perset.... .50 10% discount in carton containing 12 sets. 5587. Funnels, Aseptic Enamel Ware. Of seamless steel, white enameled, both acid and fire-proof. With handle. Diameters An Chess teinsccct gs com esi ceoe tease eater ae ele area nes 3 43 6 Ba Chi shevitiens wae trencstamnaatn arian a eitiie se aiken Yen nta7 serra ee was datas ns tap ah anit ert .75 1.00 1.30 5588. Pinar Bard Rubber, with corrugated spout which allows the air to escape so that the liquid flows reely. CADAClt yams sy abe teh bech aeals wel ene ea ata in We hes } pt. 3 pt. 1Tpt. 13 pt. CM cic oe gas peeks eee ELE eo as de SHE Ma ne Pe aL ee 55 80 1.00 1.35 5590 5590. Funnels, Buchner, Coors Porcelain, with fixed perforated plate and holes of proper size and distribution. With sufficient margin at the edge of perforated plate to permit sealing of the filter paper. Size mumberecic ites ating Pons beets 1 2 2a 3 4 4a 5 Inside diameter,mm.............. 60 75 95 115 130 155 190 Diameter perforated area,mm...... 45 60 80 100 115 140 175 Depth rim to perforated plate....... 27 37 46 57 61 66 75 Diameter of stem,mm............. 8 9 12 14 16 18 20 HAC eee en Beeson an eh need eee 1.08 1.80 2.34 2.52 4.32 5.04 6.48 5592. Funnel, Buchner Separable, Coors Porcelain, glazed inside and outside with the exception of the rim. The upper portion of the funnel with its perforated bottom is removable from the lower portion, as shown in illustration. A wide rubber band should be used as a washer for making an air-tight joint. Inside diameter 66 mm, with 45 mm perforated area, leaving a margin of 74 mm to insure sealing of the filter paper. The depth of the upper portion is 41 mm, and the diameter of the funnel tube is16mm ................... 4.80 5594. 5596. 5598. 5500. 5501. 5602. 5603. 5604. 5605. 5606. 5607. 5610. 5612. 5614. 5600, 5601 5603, 5604 5605, 5606, 5607 5614 Funnels, Porcelain, Hirsch, with fixed perforated plate. Size number. 000 00 0 1 Diameter: of top; Miss 32 scies haces eye u arty eacas di canes Gh emwne es 50 15 92 103 sf “ perforated area, mm....... OER ENG ACU ee ee ters 28 28 28 28 & SGT Ose ae Riese nce oa AA chs Oy at a eal Scat Sy Rang ag 10 10 12 14 AGH ay anc eee art ot Aneesh Pe enter it sare sean Te eg 2 ; 72 -90 1.08 1.44 Funnel, Porcelain, cone shape with perforated sides and with handle; 160 mm diameter, 240 mmdeep.. 3.10 Funnel, Porcelain, small size, perforated, for use as filter cone. Diameter,45mm.............. .80 Funnel, Hot Water, Double Wall, of copper with detachable iron legs. Can be used with glass funnels such as our No. 5570, etc. Without glassfunnel.................0 2000000000000 eee 7.20 Funnel, Hot Water, Single Wall, of copper with detachable iron legs. Suitable for use with glass funnels 150-mm diameter and larger. Without glassfunnel.................0...0..0.0.0.0.0... 6.00 Funnel, Hot Water, Single Wall, of copper. Suitable for use with glass funnels 150-mm diameter and larger. For heating with ring Bunsen Burners Nos. 2608 and 2610; or with steam or hot water coils Nos. 5605 to 5607, when used for inflammable liquids. Without glassfunnel......... 4.00 Funnel, Hot Water, Plantamour Pattern, of tin with double wall. Inside diameter of top 125 mm, with lid. Without glass funnel.............. fe Stiinta hee ahen Ree Sods nas oat Sewanee, A640 ditto, but of copper throughout. Without glass funnel................ ees As bane (O40 Funnel Heater, consisting of 10 coils of lead tubing, outside diameter 4 inch, with end enlarged to hold rubber tubing. Coils are made on a 60° cone, and are suitable for heating either glass funnels or copper funnel No. 5602, with steam or hot water when handling inflammable liquids, and where fairly constant temperature is desired; or for stream of ice or cold water where low temperatures AUTOS COSI OC Ser ee tn Reset nee OANA igs ee Ue aN cnet one roa emda Anti s nl ea REA Ae erst ees a ..... 5.00 ditto, but of block-tin tubing........ ince a egal TER apenas ers ip ure abe @ tgeioe aan 3 8.80 ditto: but ofcopper tubing: Sasn sce, nave acareen a eek nude tls oats tre RS Seek adtnostare a ake, Mee cna ee Se 8.80 Funnels, Separatory, of heavy glass, with glass stopper. Capacity, mls i.ocGiscs eck actnter faccna 6 Sag Die 200. 500 1000 2000 4000 Ba ieee i sere at dors AE WES a ee CNP RE 2.00 2.50 4.00 5.00 6.50 Funnels, Separatory, of heavy glass, with angle 60°, and stem ground to point. Gapacityiml.6.. sxaakacs ee waihiee Heiss k Be uae wmges has 200 675 1100 1400 3250 Diameter,mm...................... ehh peed AR 100 150 180 200 240 POC R I ats este Waa eo ES a he ee SE eS 2.00 2.50 3.00 4.00 4.80 Funnel, Separatory, (Terrapin Separator), as used in the U. S. Department of Agriculture, Bureau of Chemistry, for the handling of immiscible liquids which separate with difficulty because of their tendency to form emulsions; 200-ml capacity, with ground-in stopper and stopcock......... 2.50 303 5616 5616. 5618. 5619. 5620. 5621. 5622. 5624. 5625. 5626. 5627. 5628. 5630. 5632. 5640. 5642. 5618 5619 5620 5621 5622 5624 5626 5627 5628 5630 5632 5640 5642 Funnels, Separatory, bell shape, with open top. @Wapaciey slike es o.c4 ki oakn es Goa Sua So Aedes bts eee eas ae 25 50 15 100 UBF © Tee Site sn epee wer eae ke UU AUNTIE tc A nt rintec ee -90 1.00 1.20 1.30 10% discount in cartons containing 36. Funnels, Separatory, cylindrical, with open top. Capacity. mill is cinn.8 eucccessesad oie eS Sees Nes 30 50 100 150 200 250 ah Feo be da cone non ipa tee eee ede a ed 1.00 1.10 1.20 1.50 1.70 1.90 10% discount in cartons containing 36. ; Funnels, Separatory, cylindrical, with ground-glass stopper. Capacity; Mesa Seo ss ser coeur etna earns 30 50 100 150 200 250 a Cle Piper ern oe case eek Or ee Ae oR eats 1.10 1.30 1.40 1.70 1.90 2.10 10% discount in cartons containing 36. Funnels, Separatory, cylindrical, with ground-glass stopper and short stem, of stout glass. Capacity ssnmllctate, ou. seaer ces ce hea tenes UR GN toed Leen pd cine de ies balalyty A atte AA at tally tym oehe Goicdiaral aha a 500 1000 hae aes et cence eed Me Sea Nee at ile aceite te See Oak an ik San A 2s aC eoavect ee ena. onde al 2.60 3.50 10% discount in cases containing 36. ditto, but graduated: ‘Capacity; ml... .3. 0.0 .¢0.005. 0 bebe bm ee ete ne tee tees 500 1000 MVM 0 shee real ee a edn pte Ch AN gen awe g ARM Ap mena an tal Ae eta ad Suk en as 4.00 4.50 Funnels, Separatory, cylindrical, with double graduations, glass stopper and air vent. Capacity sme). ge gh ome ek oa ae ine one cae ae ee en oe Iie Atle pra ede cic srw aerate Ney ope 100 250 AC 2 ohh eed Bh a a re eet ol am see Mme Rl UA Malt ther ce Pe erg ag tata Ce a ee uc Say A 2.25 3.40 Funnels, Separatory, pear shape, with ground-glass stopper. Capacity mle fea es se dee a 30 60 125 250 500 1000 2000 ACH csck ened rer Gad oR ee cea VS 1.25 1.50 1.75 2.25 3.85 5.60 10% discount in case containing... . 24 24 24 18 18 12 12 ditto, but with air vent in stopper. Capacity, ml........ 125 250 500 1000 2000 GAC ence re oe enh take ee 8 8 ens Meee RU Maia Yas Es 2.00 2.25 2.75 4.35 6.10 10% discount in case containing.................... 24 24 18 12 12 Funnel, Separatory, for sulphonation test of creosote, as used in the Forest Service of the U. S. Depart- ment of Agriculture. With graduated tube above the bulb. Capacity, 125 ml............ 2.50 Funnel, Separatory, for ether separation in nickel determinations. The outlet stem is moderately long and of small caliber so as to hold a column. Specially designed for use in iron and steel laboratories. Gapacl bys) GOs eh ce yey ete yee nie geeks hae od ccbaynd Oars Ment Noe oy 0 eect nae Nene Maine orate 1.75 Funnel, Separatory, for nickel determinations, as described in Blair’s ‘Analysis of Iron and Steel,’’ 8th HE LEED oe eC Ope A ae ig Ne dO REE ARR A EE REAR BOE Jenene BINS GD Re ty ANE A goto ee ee et 4.00 Funnels, Separatory, Squibb, with ground-glass stopper. Capacity, ml....... 125 250 500 aC ites tear ee ROCHE LD, Sgr ae as SRA need eae Aen ates aA ee ee Nae 1.80 2.15 2.70 Funnel, Separatory, LaWall, for preventing the formation of emulsions in shaking out with immiscible solvents. See Journal of American Pharmaceutical Association, April, 1914, p. 498. The liquid to be extracted is placed in one bulb, with sufficient water to completely fill the bulb and the im- miscible solvent is placed in the second bulb. By inclining the apparatus, with the lighter of the two solvents in the lower bulb, extraction is easily accomplished by the passing of the liquids through the constriction between the bulbs. Recommended for use in the assay process for alkaloidal fluid extracts. Capacity of bulbs, ml...............0.................2.4. 25 50 100 CD A ep gi eerione etn ad am tga None Mapa tesa Aah ccs ML cna ea 2 eget Mates bS os sys 1.50 1.80 2.00 Funnel, Strauss, for estimating lactic acid in gastric juice. Capacity,25 ml..................80. 1.50 Funnel, Dropping, Walter, for examining single drops. Capacity, 60 ml......................005 2.00 804 OoLHY oH! at oo Ltt ov LH OF LH | ; yo 5644 5646 5647 5648 5649 5650 5651 5652 5656 5658 102 ee 05! 5644. Funnel Tubes, straight, with conical top, 50-mm diameter. Bionothy, cients Ghee oak cate OE Non sn Red Ott lees Poy eek i ee 200 250 300 400 es ieee err acne gaia reat h road era cre RE RSTn ate car Coe 14 14 18 -20 5646. Funnel Tubes, ee with thistle ee) 45-mm diameter of opening at oe and 45-mm diameter of bell. Length, mm.. LATS acaiies cd ee ANTS AAR AY) MC an eM Sate 200 250 300 400 a Chee ee Nee ore cca teen Bee ema met Dee A eer rin En ee cools AN en civ 12 12 16 18 3595. Funnel Tube, straight with thistle top, and 75-mm stem, as used with No. 3590 Van Slyke Apparatus.. .12 5647. Funnel Tube, with loop and conicaltop. Length, 300mm................0 2.00.00. ee cee cee .25 5648. Funnel Tubes, with loop and thistle top 45-mm diameter. TS tc crn Tris sos ee es omen te te sSp ern ce eeue eh pee on neenh Satiaducz om miege cua, Samer cea 200 300 400 ME VC Tyas neat eee ecelnct ey pier Gate es Reread oad CR a Se ed ert a 18 .20 .25 5649. Funnel Tube, with loop, one bulb and conical top; 45-mm diameter. Length 300 mm............ .30 5650. Funnel Tube, with loop, one bulb and thistle top; 45-mm diameter. Length, 300 mm. 5 . 30 5651. ene Fae, with double loop and one bulb on each side. With thistle top; 45-mm Acid. “Length TTTM eee eee a ag et TEM ne ots eee oe Rh ne dane Pe ICT Se eae eine pda) ene RL eS 5652. Funnel Tube, with double loop and one bulb on each side near top, with thistle top, 45-mm diameter, ae SHO PUES COI eerste ok ie aos A toe ities elon ag seomhasetnd cp Coneciue moe ecare meee errata seat Mat erate dy eee et ae aN iocarg Beas .40 Funnel! Tubes No. 5644 to 5652, inclusive, are subject to 10% discount in cartons containing 12 and to 20% discount in cases caitanens 144 5356. Funnel Support, Ostwald, of brass wire, for one funnel. Height 5 inches; will comfortably accommodate No. 5570 Funnels up to 3-inch diameter and 400-ml Griffin Beakers SS Berton tates ln oar agt eneunh atta .60 5658. Funnel Support, Triangular, of polished wood. Very convenient for holding funnel in position in beaker. Length: of side; inchess: ..o\.2- sae ook ee bes eee eee eee a 3 4 40 -40 -40 -40 5660 5660. Funnel Support, of wood, for onefunnel ...................-- Seen ee ee BIR A ae kre pr 1.10 10% discount in cases containing 36. 5661. Funnel Support, of wood, for onefunnel................--.... ee ee ee et re ee ee .80 10% discount in cases containing 36. 5662. Funne) Support, of wood, for two funnels, one on each side........ rae eee era eee eee ead 1.00 10% discount in cases containing 36. 5663. Funnel Support, of wood, for two funnels, both on one side. ..... eae ae Haale bah Cais een at es 1.00 10% discount in cases containing 36. 305 5664 5664. Funnel Support, of wood, for four funnels, two on eachside... 22... 6... eee 1.15 10% discount in cases containing 36. 5665. 5666 5666. Funnel Support, of wood for six funnels in one row, with slotted holes.. ...................000-. 2.00 5667. Funnel Support, of wood, for twelve funne’s, six in each row, with slotted holes................... 2.50 5668 5669 5668. Funnel Support, for four funnels, of wood, with metal clamp, for attaching tosupport............. 65 5669. Funnel Support, Leach. for separatory funnels...........0.00 00000000 ccc eee 2.50 Many important assortments, such as lamp-blown glassware, volumetric glassware, rubber tubing, | rubber stoppers, sheet-metal ware, hardware, wooden ware, etc., are made from our own designs and | specifications and bear our name only. Such items are superior in accuracy, appearance and durability | to the ordinary trade article. In some instances our prices on these goods are higher than for the usual quality, while in others they are lower because of the quantities for which we are able to contract. 306 A R T H UR Fk; Tce ©: Me AS C O M P A N Y FURNACES Wns MMMM UM SSS ESSSSSN® ml | al iif | SSS i | 1 l i mT 5 hi FLETCHER DRAFT FURNACES, FOR OPERATION WITHOUT BLAST. A chimney or stove pipe 8 to 10 feet high may be used as a fixture, and the draft partially stopped with a damper or slide when lower temperatures are required, the gas being turned down in proportion; the guide for the proper adjustment being that under all circumstances the flame must just cover the crucible or muffle, but not extend into the chimney so as to make it red hot. When the flame covers the crucible or muffle the gas is doing its extreme duty under the most favorable circumstances without waste. Plumbago fittings and crucibles must be heated slowly the first time they are used. After the first time, they may be subjected instantly to the full power of the furnace with- out injury. If the gas supply is deficient, the tap is generally at fault, and should be replaced with a new tap, and India rubber tubing, smooth inside and without wire, should be used. If muffles are required with slits for assaying and oxidizing, slits may be easily cut in the back with a penknife before the muffle is used. After it has been exposed to high temperatures, the plumbago does not cut readily and it requires more care than if cut before. Fletcher Crucible Furnace No. 15, for operation without blast. This will take crucibles up to 4 by 33 inches, holding about 6 lbs. when full, and with a 43-inch gas pipe supply, will rapidly melt a crucible of gold or silver. Flame space in furnace, 61-inches diameter by 53-inches high. Outside dimensions of clay parts 73-inches diameter by 10 inches high. Height of furnace from table to top of lid 18 inches. Weight as illustrated, 53 lbs. Weight of No. 15 burner only, 37 lbs. Maximum gas consumption 75 cu. ft. per hour. 5676. Furnace, Fletcher Crucible No. 15, as described above, with 6 ft. of pipe, one clay crucible No. 3, clay cylin- Geran tones sciences oA eae eae nnnh actin Gea emai e rh thd PA IGae nae hig imi aint an cate nae 40.00 5677. .Fire-Clay Casing; only;for'above Wurnaces;.3 3.6. ces en vada net tose ne neds eee an eee 6.00 678.) oLidsonly, for aboveWurnaces, 2.20) 5 cai ciccveadsbtcrhanne- oo wag ce aia cas eee ees Nae en i Sette ta 3.50 5679. > Grate; only; forabove PuUrMacCes.. | 6 conadancin UN's anata hb araish wute sunlduanter een anlar nuade ek emu eAN ea 2.75 5682. Furnaces, Fletcher Muffle, for assaying, enamelling and all purposes where exact temperatures are required not exceeding the fusing point of copper. The burners for these furnaces are of the same construc- tion as No. 5676. Prices include plumbago muffle and dome, crucible tongs and 6 ft. of chimney pipe. IND ER ccteleee tiene das Sera 38 4 5 6 Muffle space, inches......... 5; x 5t x 5; 73 x 63 x BF 83 x 73 x 63 101 x 94x83 Bore of gas pipe, inches...... 3 a 1 1 Gas consumption per hour... . 72 cu. ft. 96 cu. ft. 120 cu. ft. 225 cu. ft. OAC ap ia ee 66.00 78.00 102.00 118.00 5683. Domes, Perforated Plumbago, only, for use with No. 5684 Muffles in above Furnaces. To fitfurnace number. .......0 00.00. eee 3 4 5 6 Bx Picco oe Ne icc Meebo UTS nent inte casa oN ee Me. ets 2.85 3.15 3.85 4.55 5684. Muffles, of Plumbago, only, to fit above Furnaces. To fit furnace number....... 3 4 a) 6 Inside dimensions, inches.... . Bx 4x25 3% x 54 x 3 43 x 63 x 4 6 x 8) x 45 Bache schon ees 2.75 3.50 4.25 5.00 Fletcher Crucible Furnaces No. 63. This form of furnace is simpler than No. 5676. It is powerful enough to melt gold or silver, but slower than No. 5676. Can be used for scorifying or cupelling. The lid can be pushed sidewise sufficiently to give access to the interior of the furnace. The burner is constructed on the same principle as No. 5676, and may be used with natural, illuminating or gasoline gas. Maximum gas consumption 75 cu. ft. per hour. This is the furnace recommended by Walter Lee Brown, of Chicago, for roasting ores. 5686. Furnace, Crucible, No. 63, with clay parts 103 inches long by 73 inches wide by 63 inches high outside. Flame space 8 by 3 inches. Requires 3-inch gas supply pipe. Complete with one length of pipe, damper,-clay crucible No. 1,and tongs... cco che ees ek ete ik eo bees dence eee esgic em ein ea 45.00 5687. Furnace, Crucible No. 63a, with clay parts 124 inches long by 83 inches wide by 73 inches high outside. Flame space 43 by: 4 inches. Requires }-inch gas supply pipe. Complete with one length of pipe, damper;.clay crucible'No..3; and. tongs. 22.2 ogc eg bee ke ch ee eG be nee 50.00 Monitor Gas Assaying Furnace, No. 630. In this furnace the flame arises from the burner shown at the left of the illustration and passes horizontally through the body of the furnace to the chimney. Its form and mode of operation are somewhat similar to that of a reverberatory furnace, the movable bricks when in place forming the roof. The exterior dimensions are 20 inches long, by 7 inches wide, and 53 inches deep, exclusive of cover bricks. Height from table to top of cover, 15¢ inches. Weight as illustrated, 55 lbs. It will accommodate four 23-inch scorifiers, or eight to ten cupels, at one time. The size of the floor is 10 x 3% inches, and the cavity is 38 inches deep, accommodating a No. 1 Plumbago or Clay Crucible. As there is no direct heat under the floor of the furnace, a platform is furnished on which the scorifiers and cupels are placed. The heat passing under as well as over the platform, the articles placed thereon are heated quickly and evenly. The gas supply should come through a 3-inch pipe from a tap at least 23-inch clear bore, so that, the gas will be delivered at full pressure. Proper connection should be made by means of small stove-pipe from the furnace to a chimney. The advantages in this furnace are that it is possible to see every step and stage of the operation, and there is such perfect control of the heat that a higher or lower temperature, a reducing or oxidizing effect, may be produced at any time. It is noiseless and free from the annoyance of dust and ashes and excessive heat in the room, and is especially desirable for summer use. Gas consumption 75 cu. ft. per hour. For operation with illuminating, natural or gasoline gas. 5688. Furnace, Monitor No. 630, as described above, complete with damper, one length of chimney pipe, No. 1 48 clay cruciblesand tongs. cern Aceh cng town de bikin aia hie ncn de nt pa Seles eam ee keeles -00 56893, Fire: Clay: Slabsf Or COVER wc ccnn 2 sat issue dian oa eI Ue Sk ce ce ge ey phen oe uh plant hS ORIN nies 1.20 5690; “MUrnace:BOd ys. kaso eh A tara RGeuES — taase pu ners unde meets aN Sad dag wees ees me SERA 13.50 5691. Platform.......... Be teem Oe en Ne lic Joa 40 FURNACES, FLETCHER, FOR OPERATION WITH BLAST These furnaces can be used with Foot Blowers, Crowell Type A Rotary Air Pumps or any other form of blast. 5692. Furnace, Fletcher Crucible, No. 40a, Injector Pattern. For use with illumi- nating, natural or gasoline gas. Nearly noiseless in its action and more economical in the use of gas than the older form of burner. The furnace consists of a simple pot for holding the crucible, with lid; all mounted on a suitable cast iron base. Take a No. 00 clay crucible hold- ing about 10 ounces of gold, and requires 3-inch gas supply pipe. Maximum gas consumption 24 cu. ft. per hour. Can be used with a foot blower or a steady blast of air. All fluxes should be kept away from furnace casing. Without foot blower, but with one No. 00 clay crucible......................... 6.75 — 5693. Furnace Body, only, for above Furnace........ 2.00 5694. Furnace Cover, only, “ He OP erie teleaceaa 1.00 308 5695. 5693. 5694. 5696. 5697. 5698. 5699. 5700. 5701. 5702. 5703. 5704. 5705. 5706. 5707. 5696 Furnace, Fletcher Crucible, Blast, No. 40b, for kerosene, exactly same as No. 5692, but with burner de- signed for use with refined petroleum or kerosene instead of gas. Can be satisfactorily operated with foot blower. A thin layer of powered quicklime will prevent the adhesion of the crucible to the casing. All fluxes should be kept away from the casing. Without foot blower but with No.00 Clayecruci blevateratted eetiie Ma wits ets ee eh re eee RN NMR mta ieee g ete 8.75 Furnace Body, only for above Furnace.................................... oe een e ne 2.00 Furnace Cover, only, “ tS BE ee code atch kU ch arth oa Dy Pot AM ieee Men ie oh A sea 1.00 Furnace, Fletcher Crucible, No. 41, Injector Pattern, for operation on illuminating, natural or gasoline gas on same principle as No. 5692, but of larger capacity. Takes a No. 1 clay crucible, capacity 2lbs. Maximum gas consumption 42 cu. ft. per hour. May be satisfactorily operated with foot blower. All fluxes should be kept away from the casing. Without foot blower, but with one No. 1 Cla yACLUCHD] Chance. t ha eee Seether? Mecano ye AiR am ann She WAM eile Afar 10 50 Furnace Body, only, for above Furnace..................0.000 00 cece 5.50 Furnace Cover, only “ oe pe nese Nera cere ae ee ie Ga stakes eee eee i Dome, only “cc “cc “ 5700 Furnace, Fletcher Combined Muffle and Crucible, No. 141, for use with illuminating, natural or gasoline gas. The gas supply must be from a } or 3 inch pipe and clear way tap. Maximum gas consump- tion 100 cu. ft. per hour. The body of the furnace will hold a No. 6 crucible. The cover has a pro- jection on one side which will reduce the height of the cavity of the furnace some 2 inches, or to the proper size to hold a muffle 33 x 23 x 6} inches, or a No. 3 crucible. By reversing the cover a No. 6 crucible may be used. Without foot blower, but with plumbago muffle and No. 3 CLAY: CTUCl Dore tok ah aed en id ot emcee eect eh taht ats TEE Nea Soy alia GOP laa pede easel ech Hie 25.00 Firé: Clay: Body, .coverand: two plugs’... .co3 fas oe dies rea aan oo A PEARS ep Pe Ge 17.00 Clay Muffle, only, for use on Fletcher Combined Muffle and Crucible Furnace, inside dimensions 3} x 27 KO 1 AN CHES, Onks ak aie ctanicmusre es Ad aoe ia onto et A hea Se Nek, Moe nia Whilemtanlt tas cl Acar eedhs el goereaicen Paine yord 4.10 Plumbago Muffle, only, for use on Fletcher Combined Muffle and Crucible Furnace, inside dimensions 33 KDR GE INCHES v.25 et saaeiam da atonten oe Meco eal hace ld earls Seay cous Ronan autor os Oaebeateatlg Gases sa otyas toeanaiae ie 4.10 Furnaces, Muffle, Wiesnegg Pattern, as widely used for incinerations in sugar analysis. Furnished with Bunsen burners mounted on one base, each burner equipped with a wing top to spread the flame evenly. A very satisfactory and efficient furnace for ash determinations. INtam ber Of bUrMers 4 acento cerry secasa-eurhiee SU ate maid Pare e Reus ance ahh Beas 4 6 Sizesof mutile; inches cemany its see dows pena en cane eee § Shee shots het 6rx4x25 10x6x4 ACH ee eer tytn eee OT! Gh MeL RTE TAES AE tees Webs entree SIF ect ate 33.50 50.00 Mufiles; Clay, for above. Purnace sci cce8 cae ieee eens Waseem eens 1.35 1.60 Furnace, Fletcher Combustion, for illuminating, natural, or gasoline gas. For high temperatures, it should be used with foot blower, or other form of blast. Maximum gas consumption per hour, draft, 30 cu. ft., blast 60 cu. ft. Length of furnace, 12 inches. With adjustable flame length. 22.00 Fire Clay Casing Tile, 6 inches long) .0.55 cscs gee eds kare psd Dba yp ee dEUS oer as 1.00 A i Belo) R H T HH © M x 'S C O M P A N _ Y 1hin. 5708, 5711 5712, 5714 5713 5708. Furnaces, Combustion, for gas heating. Each burner is fitted with stopcock and air regulator, and height of flame is adjustable in relation to combustion tube. These burners are suitable for use on natural or illuminating gas only. Complete with clay tiles and gutters. Length of heating surface,cm................ 00... 00 ce eee 25 35 45 60 Number: Of burners srcrcnts cistvniee afi Be tan acolo le alec alas a tates 10 15 20 25 CW a sare oon erence nee bender othe des eh enretdheh earner OA area olathe a aR coms . 37.00 44.50 51.00 59.75 5709. Clay Tiles, only, for use with No. 5708 Furnaces. : Wraidthsanchess rece seca oa tester iet errs te te Rene Png Se aera thn Ae tees aeons 13 2% TAC bier setae aster tacse, oes tea aN SN ours Eeeelest tM Deh VO Myh ary doe Onna hepa etn Reet eae Soa nace .20 .20 5710. Clay Gutter, 10 inches long, for No. 5708 Furnaces.........00.0..0 0000 ccc ces 16 5711. Furnaces, Combustion, exactly same as No. 5708, but equipped with Universal Burner for use on any kind of gas. Complete with clay tiles and gutters. Length of heating surface,cm................ 00.00 .0000000. 25 35 45 60 Numberof burnerss 2. scete cuss aus eoein? apt wh sauwiee cee tutte 10 15 20 25 SAC Mtns AG oe Ara Ae UNAS oe Uae Ad cose eg akaaies Loe Ree rie ae 37.00 44.50 51.00 59.75 5709. Clay Tiles, only, for use with No. 5711 Furnaces. Widthjrin ches 2o7 sgetun.as. eNews en dedieae iy cea wes a at aetls tae Wave yk oc uid Mtaby Soccer ale a eer Ba Chgset tess ed ae een ee yo ae. Reese Mere Reet er age RS an aes eg eG 20 20 5710. Clay Gutter, 10 inches long, for No. 5711 Furnaces........0..0.0000.0 0000 ccc ees 16 5712. Furnaces, Combustion, modified form, with side windows of mica for observation of flame, and clay tiles of improved construction. Each burner is fitted with air regulator and stopcock. For use on natural and illuminating gas only. Complete with clay tiles and gutters. Length of heating surface Cm ici. osiioe can wee eee ae oes Gale a ad weeks 38 56 80 Niurmber Of burners a. skeen cree any pene uet Geen stort nen Rian aleye eos ene i 15 80 ACH sco e Ree Rippin ae Pum SOAS Bo rcuainhan gute te SRE Ph ah A pate neg Senay ad 54.00 64.00 78.00 57192 Top Tiles; for No.5712) Murnaceés:.. Hach sso scax hain once 3 wae oa tas sb eo a RS .20 5710. Clay Gutter, 10 inches long, for No. 5712 Furnaces........00.00000 000 ccc ccc ccc ete ees 16 5714. Furnaces, Combustion, exactly same as No. 5712, but equipped with Universal Burners for use on any kind of gas. Complete with clay tiles and gutters. Length of heating surface, cm... 0.00.00... eee ec ccc eees 38 56 80 Number ofsburners:cerascs ts recon Bro vent heat en bous Sadia io 15 S20 Macaig 0e ie iain ct ree ene ct Mion PEAS ah, en thud ant Oe eee one 54.00 64.00 78.00 57s. “Lop: Lile. tor Noo (14-Puarna ces. ith x A jeecath uh ate teas te dees poe amon eta oe echt da ingen ve weaioces 20 5710. Clay Gutter, 10 inches long, for No. 5714 Furnaces... 00.00.00. cece ccc cc ete e eee eeeeee 16 310 i i a nny i i ia fs a Pe ah ay aK : i oe nS m a if “i a | yy TUBE FURNACE, FREAS ELECTRIC, for organic determinations where explosions are to be made, of the same general construction as Freas Ovens and with Freas patent temperature control. Recommended as a safeguard against untimely explosions so frequent with gas heated furnaces due to fluctuating gas pressure, etc. Walls are extra thick and front is of heavy cast iron, to which is attached a heavy hinged composition hood to prevent the contents of the tube from causing personal injury in case of an explosion. This hood covers four openings in the front, each into an iron tube leading through to the back of the furnace, where it is covered with a threaded cap. This cap has a quarter inch hole in the center to enable the operator to push out the tube with a rod provided for the purpose. This opening is closed with a metal plug. Each iron tube takes a seamless steel tube 1} inch diameter and 25 inches long, closed at one end. This steel tube carries the glass tube into which is sealed the chemical to be tested. The heating plate is wound for 1500 watts to give a maximum temperature up to 260° C. This Furnace must, therefore, be connected directly to a line of this capacity. With ther- mometer No. 7858 reading from 0 to 300° C. 5715. Furnace, Tube, Freas Electric, as above described, with heating plate wound for 1500 watts at 110 VOMUES Sot cttw oe eee re eek Amd eet ARR La A sis Norn a Bont oe hats pee GAA aw CLS OAS PKR ee a 5716. ditto, with heating plate wound for 1500 watts at 220 volts................................ 235.00 7858. Thermometer, only 300° C, for use with above Furnace ................0.. 0.00 cee eee eee eee 4.00 5718 0 a cet AWT CO _.) 5717 5719, 5920 Furnace, Tube, Carius, for gas, of sheet iron, with five tubulations 20 inches long by 1} inches Sees e with Tube or Bomb Furnaces, with one end closed and with constriction for con- si ee aloe off the open end. Of stout resistant tubing, more readily sealed than No. 5720 but sufficiently hard for most purposes. 5717. Length to constriction, mm........-.-. 002s eerste eee ee eee 415 500 615 Outside diameter, mM..........-0-. 00000 e etter e eee 18 20 22 Bris Ti sic cae ecw dts viet meets AR ee eee ea cee ear 40 45 50 ‘ Carius or Freas Furnace, 24 inches long by 1 inch outside diameter, with j-inch wall and ata, Tube ee. Of lime glass tubing for use at ordinary temperatures.................... .70 5720. ditto, but of Pyrex glass, for use at high temperatures. zs .0/ i. Wages anges Web acts Pe aise ates 1.60 311 5722 5732 FD-201-204 FURNACES, HOSKINS Type FD, for maximum safe operating temperatures up to 1000° C (1830° F.) The minimum temperature that can be maintained with standard rheostat is about 480° C (900° F.) All type FD furnaces operate equally well on direct or alternating current, but voltage must be specified. Carried in stock for 110 and 220 volts only. Rheostats as listed should be used with all type FD furnaces. The Heating Element in these furnaces is of heavy Chromel ‘“‘A”’ wire wound in spiral coils; and all parts requiring renewal are easily accessible and can be replaced in the laboratory by the operator himself. Type FD furnaces are built in three models, 7. e., Crucible, Muffle and Tube, as listed below. All are furnished with full instructions as to installation and operation. Types FD101, 108, 104, 201, 202, 203 and 204 are furnished on legs 5 inches high for use on laboratory table. Type FD206 is supplied on an iron stand about 40 inches high to stand on floor. A wire support as shown in illustration is also supplied with Type FD101, so that it may be used in either horizontal or vertical position. 5722. Furnaces, Crucible, Hoskins Electric, Type FD, without rheostat. STO veece er nts Gis er tetnee wi wears aah ae Sued lens | Wey Me frees typ es oon ee FD101 FD103 FD104 Size of heating chamber, inches..................0.00 00.0000 cece 2x24 4x4 5x5 Each, without rheostat, for 110 volts........0.00.0.00.0.0.0....... 28.00 55.00 85.00 5723. Each, without rheostat, for 220 volts...............0.............. 28.00 55.00 85.00 5724. Rheostat only, for 110 volts.................0 0.0.0.0... 000... Bee cnt 12.00 16.00 16.00 5725: —-Rheostatconly;for220 voltsionh 6 cton aged Aa ce nec gh ek ee ee 12.00 16.00 16.00 Replacements 5726, Refractory only, without: Wites..s s.< 4 ce oe et ch bac ek wd Sao ee ae el 2.00 7.00 8.00 5727. Chromel “A”? Wire only, for winding, 110 volts ........0....0.0..0.00...0.... 1.75 7.00 9.00 5728. Chromel “A” Wire only, for winding, 220 volts..................0.......... 1.75 7.00 9.00 5729. Heating Unit, complete, for 110 volts.............0.0.0.0 00.0... 3.75 14.00 17.00 5730. Heating Unit, complete, for 220 volts..............00.0 0000000000. eee 3.75 14.00 17.00 ee serial number of the furnace in which replacement part is to be used must be given with each order for such parts. 5732. Furnaces, Muffle, Hoskins Electric, Type FD, without rheostat. Type...... fe oe ee TNS FD201 FD202 FD203 FD204 FD206 Size of heating chamber, inches.. 34 x23x744x3x10 51x32x12 74x51x1412x8x 26 Each, without rheostat, 110 volts 70.00 85.00 115.00 150.00 375.00 5733. Each, without rheostat, 220 volts 70.00 85.00 115.00 150.00 375.00 5734. Rheostat only, for 110 volts.......... 14.00 16.00 21.00 35.00 35.00 5735. Rheostat only, for 220 volts.......... 14.00 16.00 21.00 35.00 35.00 Replacements 5736. Refractory only, without wire........ 10.00 15.00 20.00 30.00 55.00 5737. Chromel “A” Wire only, for winding, TROVOlS cies tee aera es 6.00 9.50 16.00 23.00 35.00 5738. Chromel “A” Wire only, for winding, DOO VOLS ese Sune rete cen 6.00 9.50 16.00 23.00 35.00 5739. Heating Unit, complete, for 110 volts 16.00 24.50 36.00 53.00 105.00 5740. Heating Unit, complete, for 220 volts 16.00 24.50 36.00 53.00 105.00 Note—The serialnumber of the furnace in which replacement part is to be used must be given with each order for such parts. A larger furnace of this type,i.e., D207, 12x8x26inches,is manufactured and supplied by us on special order only. 812 5732 FD-201-204 (Knocked down) 5756 5746. Furnace, Combustion Tube, Hoskins Electric, Type FDH302. Size of heating chamber 1} by 12 inches, without rheostat; for sl 10cVoltisi a 4 — C. x 7 4 ab, Oo < > wn a ° = v > Z ~< 5976 5977, 5978 5976. Throttle Control Valve, for the safe and accurate control of very small quantities of gas from high-pressure cylinders, such as those containing CO, in connection with freezing microtomes, and oxygen in calorimetry and in carbon determinations in steel analysis. A very slow motion is imparted to the valve by means of the worm gear with threaded coupling to fit standard cylinders, such as our INOS 5 IOC REL C isan erences atch ate Meas scan sua aes Re hah Fee GS eben aE SNA tae ek Tach aera ahs aon 5.25 GAS PRESSURE REGULATOR AND REDUCING VALVE, Hoke-Pheenix. This device, approved by the National Board of Underwriters, is designed especially for use on high-pressure cylinders of oxygen or hydrogen for reducing the high pressure under which the cylinders are charged to the low pressures for actual use, affording at the same time delicate control as is required in H-ion determinations by the electrometric method, in calorimetry and in carbon combustions. The safety inlet coupling prevents a sudden rush of pressure into the regulator and the large coupling opens and allows the gas to escape in case of a rupture, thus preventing an explosion. The safety perforated bonnet will release the gas quickly if the diaphragm should be ruptured, thus preventing injury to the user. The large dial indicates how much gas is in the tank and reads in pounds per square inch from 0 to 3000 lbs. The small gauge shows the delivery pressure, which is controlled by the regulator, from 1 to 40 lbs. as desired. The oxygen regulators are finished in gilt and the hydrogen in silver lacquer for the purpose of ready differentiation. The cylinder couplings on the oxygen gauges are fitted with what is known as the “Linde special” thread which fits oxygen cylinders of all the larger manufacturers. The cylinder couplings on the hydrogen cylinders are fitted with what is known as 3-inch i.p. left-hand thread used on the hydrogen cylinders of the larger manufacturers. 5977. Gas Pressure Regulator and Reducing Valve, as above described, for oxygen cylinders; with directions POMOPETALIONT: ore ees erin ieee leas tN Se ena See RE Ants porat Oo ta ENR Ean enti e ota the By sce ae 33.00 5978. ditto;,-forhydrogenceylind ers 928) 20 kao. pers nants dete d cue aute has Age creole Obey baleen abet enemy suslauenn Se 33.00 EDWARDS GAS DENSITY BALANCE CAS L fT Se ER pe re eee ee \CULTLLTLDTALLLSLLITITIECLILILSTLLLTLLITLSLELL SILA hy erent bbb hd Lapp bh hbbbhleabeblodea J Longitudinal Cross Section of the Beam and Case of Vertical Transverse Cross Section Edwards Gas Density Balance of the Beam and Case GAS DENSITY BALANCE, EDWARDS. According to Boyle’s law, the density of a gas is proportional to its pressure; and the buoyant force exerted upon a body suspended in a gas is proportional to the density of the gas and, therefore, to its pressure. Hence, if the buoyant force exerted upon a body is made the same when suspended successively in two gases, then the densities of the two gases must be the same at these pressures; or the densities of the two gases at normal pressure are in inverse ratio to the pressures when of equal buoyant force. The apparatus consists of a balance beam B carrying a sealed cylinder on one end and a counterweight on the other. The balance beam with its support is mounted in a gas-tight chamber to which is attached a mercury manometer. In operation, the balance case and manometer connections are filled with dry air through the inlet I and the pressure adjusted by removing the excess gas through the needle valve E until the beam just balances. as determined by observation (through the adjustable lens L) of the cross line on the end of the beam. After de- termining this pressure, the balance is evacuated through E and filled with the gas, the pressure is then adjusted until the beam is again in equilibrium. The specific gravity of the gas is then the ratio of the total pressure (man- ometer reading plus atmospheric pressure) required to balance the beam in air to the total pressure required to balance it in the gas. 828 5980 Beam of Edwards Gas Density Balance Mounted on Holder i" 5980 5982 EDWARDS GAS DENSITY BALANCE (Continued) The balance case is mounted on a firm table and the manometer attached at A by the metal union. The manometer is filled half full of clean mercury. Ifthe mercury contains dust or the surface is fouled, it can be cleaned by filtering through a paper filter with a couple of pin holes in the bottom. The water jacket should be filled with water at room temperature or sufficient time be allowed for the water to come to equilibrium with its surroundings before making a test. The beam is then placed on its bearing and inserted in the gas chamber, the support being held firmly in place by the friction ring to which it is attached. A pair of tongs is provided to aid in removing the beam sup- port. The beam support should be adjusted to be exactly level; this can be done by tapping the balance case and observing whether there is a tendency for the beam to slide to either side. The cap closing the gas chamber is then screwed on tightly and the apparatus tested for gas tightness. This can be done by reducing the pressure with the vacuum pump to 200 mm or less, closing the connection to the pump and noting whether the gauge shows an appreciable change during a period of five minutes. The balance case is next filled with dry air by first evacuating and then allowing air to enter slowly through a small calcium chloride tube attached at I. A plug of cotton should be placed in the end of the drying tube to prevent dust entering the balance case and becoming attached to the beam. If the balance contains gas from a previous determination, this should be flushed out by evacuating and refilling the requisite number of times to secure an uncontaminated sample. Air should be allowed to enter until the pressure is slightly in excess of that necessary to secure a balance. The exact adjustment of the pressure can then be made by withdrawing air through the needle valve E, which enables one to change the pressure very gradually or in steps of a few tenths of a millimeter at a time. When equilibrium is reached, the pressure on the manometer is read and the atmospheric pressure is deter- mined from a barometer. The balance case is then filled with the gas whose specific gravity is to be determined. After proper purging the pressure is adjusted in the same manner as with air. The gauge should always be tapped just before reading in order to eliminate the effect of the mercury clinging to the glass. In case the density of a sample of hydrogen is to be determined it is almost necessary to use pure hydrogen in place of air as a comparisom gas because of the great difference in pressures necessary to balance the beam in hydrogen and in air. 329 A- oR- TH Uy GR H. rT H © M A S$ Co Os OMY Re An END, The sensitivity of the beam can be adjusted by raising or lowering the needle points and by raising or lowering the small nut mounted on top of the beam. The longer the period of swing, the greater the sensitivity, and hence the accuracy. This adjustment must, of course, be made before the beam is placed in the balance case. The beam has already been adjusted for high sensitivity and should not be changed unnecessarily. The position of equilibrium of the beam can be changed by means of the lock nuts at the end of the beam. It is convenient to have it balance a few millimeters below atmospheric pressure for most work. The balance case may be gently tapped in order to start the beam swinging when there is a tendency to stick. If this sticking is serious, the needles should be sharpened and the glass bearing examined for imperfections. If found to be scratched, it should be replaced. Failure to secure constant readings with air or gas is usually due to an imperfection in the needles or bearings. Any fine, sharp needle can be used for this purpose; the needles should be examined to see that they are not bent or perceptibly rounded at the point. The exact length of the needles should be measured before removing, to aid in adjusting them after replacement. The method of recording the data and the calculations involved are given in the following example:— Barometric pressure (millimeters)... 0.0.0... tenes 756.4 {396.7 Gauge readings with air (millimeters) ........0.00 000.00 cece eee ee eee eee 1890.3 Pressure (millimeters) . . Oy Peeve chm canta wide Saul ee ok aN ecole Sek Gla ela eh miAie lr hae Shade _ 6.4 Total pressure (millimeters) Dapp Gia STAGE eee baie ERY Ee PRN SSH 750.0 Gauge readings with gas (millimeters)... .. ee ee Pressure (millimeters) . nA Se cohol cH RL etait cs hae chee de ae ede eee eR Oyo + 408.1 Total presstire (millimeters). Pe Ree RRA el chant lees wk ob hc zach seen dk Gt onte es aS eis 1164.5 750.0 SPECihe Bra VaCy eed. © cases se. 2 See es Se: Cases eA nin Se Pears Bed EAS DN TR eee 1164. In addition to the balance and manometer, certain accessory apparatus is required See is already avail- able in most laboratories. This includes a barometer for determining the atmospheric pressure and a vacuum pump for evacuating the balance case and connections. A pump giving a vacuum of 1 mm of mercury, or better, is desirable, although a good water pump can be used if nothing else is available. When using the water pump a calcium chloride tube should be inserted between the pump and the balance. A small leveling bottle filled with mercury, to be used as a gas compressor, is necessary unless the gas sample is already under sufficient pressure to bring the beam to equilibrium. A more complete discussion of the method, its possible sources of error, and details of operation will be found in “Technologic Paper No. 89” of the Bureau of Standards, copy of which we shall be glad to send upon request. 5980. Gas Density Balance, Edwards, as above described, complete with manometer and sufficient mercury for charging same; ans Canryin gCASC sce). os atecicitact eanlA bacus itodaranardcr 9 aks Sab ae ea ete eater ache ts 125.00 5981. Needle Points for beam, carefully sharpened and inspected. Perdozen....................... 1.50 5982. Leveling Bottle, with stopcocks and reservoir, but without rubber tubing, to be used to compress gas into balancecase*whenmecessany: 232 sich e pie. Glen arnt eiale permeation oasah eae nea Lisheiantatne wate aaobace 9.00 2084. Barometer, Observatory, U.S. Weather Bureau Pattern... ........... 00000 cece eee eee 51.80 5286. Filter Pump, brass, 53 inches long for 3-inch pipe thread.................. 0000s eee eee eee ee 1.80 5288. Filter Pump Couplings, brass, with faucet thread for above. .............0 00000 cece eee ae .30 5289. Filter Pump Couplings, brass, for connection with faucet without threads...................... .50 1012.. ~Pumip, Vacuiimy and: OL WEaSSi<. 2 aeoes scaceesccer ose Sates el tt atin hae onan 18.35 1 ' ' : 1 ' ' ' 5342 5987 5985. Gas Generating Bottles, stout walled, for generating gases. Without fittings. Cap acl t yer tial te delice oe ec scan sates ene ores G weyeaed NeteetOe Aas patna fr eee teat 250 500 1000 BA Che) scestoortet uctr ese eet N Yaeh Ay A ed tac acts eects Rea dA anes ee ep a .25 35 40 5342. Gas Generating Flasks, Pyrex Glass, for generating gases, etc. Capa cityzamlln ese rors cen eta biel as aan LNs heel os i AE Ge 250 500 1000 Chis coe rete aca eee os ere San ammeter, UO a Aa 22 29 42 5986. Fittings only, for gas bottles, consisting of plain thistle tube, rubber stopper and outlet tube. RO MtHbOtbles svi 2 aes sauce eks oaid nae he mets eed ares peters ete ie ae 250 500 1000 IRE SObN a aa anata staple wiser tieeeeen raster hora ene Men Se din fd ule ee a 32 .36 38 5987. Fittings only, for gas bottles, consisting of safety thistle tube, rubber stopper and outlet tube. Boris poublessTinllls se ctiins Atri: honed yu abt rues | cre a a wane eu fn 250 500 1000 EGE SC Ue caput hd hea en Ori aka Aun oes ae ah trnsey haan eeu eM Sita oak enol Cet oe, Se BS -40 45 ~~—~—«CO0 S T H UR, T HO M A 6 CO MM F & NX 5989 5990 5991 5988. Gas Generating Bottles, with ground-glass stopper, safety tube with glass stopcock and delivery tube. Capacitys ann! ina he tc tierra Sok BN cr ON tate Ace Rate oh Cree tte Piemnt e ahr ma Teen ate 4a 250 500 Bac We dre ae hate as Sek Mca peter OMe aati onctn one eer gan) tet eet cc ea dae (2.25 «3.00 5989. Gas Washing Bottles, Allihn, with ground-in glass stopper. Capacity, ml............. 250 500 ACN es ia nye edo eee a See patie he A eee RA LGR AR raat 3.00 4.00 5990. Gas Washing Bottles, Drechsel, high form. Capacity, ml.......................005. 250 500 BACH i sos t ce aetereredt rnp iitoe os mina at-oteien Aue Ss kone oe Rect ptanlved tits Saaiaonls tess! afd 1.25 1.50 10% discount in cases containing 24. 5991, dittowlow form: ~Gapacity,mllj.3.0 sibs A eee ina se ee ae ea SESE 250-500 Ba Class scant tycrs pig cease aly don te Gieevcs tor ase em eae iedeweegatede 1550: 2.00 10% discount in cases containing 24. 5992 5992. Gas Washing Bottle, for caustic potash solution, part “‘P” of the Fleming Combustion Train..... 1.65 10% discount in cases containing 24. 5994. Gas Washing Bottles, Williams, as used for the rapid and complete removal of water vapor from the ventilating air currents in respiration calorimetry. Also valuable wherever it is necessary to wash gases thoroughly and rapidly. The bottles are of light weight and provide for accurate weighing. Capacity; quarts: 2.6: :4ictiiakomasuecppeed she edealh colar ER Ui eee Se ha est 1 2 CI ecceh so esrecs ak eA Aub Sead sn RHO Gg OGD eee HAUG pee O ANE Sas Son 2 Auta 8.00 10.00 6000. Gas Generators, Kipp, improved form, for continuous production of hydrogen sulphide, etc., with large side opening for filling. Complete with Geissler stopcock, funnel tube, etc. Capacity mletteee cece is 16h bea ae eta 500 1000 2000 PEGI ce Seer er eR ec tirus chase SoA coos ok ars ame rane ns Roar el a 6.00 7.75 10.00 6001. Rings of hard rubber, for use in Generators No. 6000, to prevent the iron sulphide from falling into the lower chamber. To fit generator,ml............... 5500 -e seers 500 1000 2000 Peat CHR ees cece ing ok Spies Seva Bees eee Soe ee BE Gecaval Mare ann pcm ae -90 .90 -90 3 Generator, Johnson, for hydrogen, CO, and HS. Made of a heavy refractory composition, with all Er Sane Sante replaceable. Capacity, 1700 ml in each bulb. Complete with instructions for use.. 30.00 6003. Bottom or middle bulb only. Each Serer ee ee oe 5.00 6004. Top, with bulb and tube extension in one piece........- 0-0... eee veers 6.00 331 | oman feeqan] mafun pun petifeanpon}rnpes Frtanyan |e = ol Spnteahanpe e& 6006 6010 601 6005. Gas Holder, made of leaded iron, painted and mounted on an iron frame, with sliding receiver, pulley and weights for regulating the oxygen pressure. Capacity, 20 gallons................... 70.00 6006. Gas Holders, Berzelius-Pepy’s, improved form, of heavy copper, with glass gauge. Capacity Gallons edt Sater ws uses sruen ne bent cadl ton apo Dee ad hovacaees ate ae akee ie ba aa 5 10 ACH S ea saike elias s ees Rec aes ae stig. SUE eect SoS Peat to CSS Ta aU itl Seer ese oeaTereS 36.00 48.00 4 Gas Machines for generating gasoline gas for use in laboratories where illuminating or natural gas is not available. These are supplied on special order of approved makes in from 15-light capacity (8 Bunsen Burners) to 500-light capacity (250 Bunsen Burners), at manufacturers’ original prices. They are not carried in stock. 6010. Gas Measuring Tubes, of glass, graduated, closed at one end, without stopcock. AD aClt ye. Alt Serra ia cco mcr aene Reuter ina oe at eeasiasares arena eae cues ana ales On tie occa ks 50 in 7» 100 in t ON eal anteater cis eehirat aay alcdty tes Uden Dateien ut oecdoskins Mid ani reper nearness 1.60 2.50 6011. ditto, but with stopcock, capacity 50 ml in goths... 6... cee eee teens 2.85 6012. Gas Regulator, for shutting off the supply of gas at any desired time, consisting of a specially constructed clock with timing device and gas valve, with }-inch gas passage. The gas valve is connected by rubber tubing between the gas supply and the apparatus which it is to regulate............ 6.50 6014. Gas Palladium Tube, Hempel, for the absorption of hydrogen, with about 2 grams of palladium SOM GO eee ko sceeau ane rcucive wade idiisrca peat pres: aes fave osm ap siad- ees alata epee a en eter es AU Seaya Wee oe ene eee ale 3.50 6018. Gas Distributors, of brass, with one supply pipe and three burner connections with stopcocks.... 6.00 6019. ditto, but with four burner connections with stopcocks.......... 0.0.0 eee e cece ec eceueseue 6.80 Gas Cocks, Connectors, Distributors, etc., see page 559. 6022. Gas Filter, for use with either the Greenman or the Roux Bimetallic Thermo-regulators, to clean the gas of coal tar or other impurities, thereby securing more satisfactory working of the MOQUIACOTS ise oy sntee cytes eae nteyesorers 7.20 6023. Gas Meter, Experimental, Bohr, original make, as widely used in physiological work in the de- termination of the respiratory exchange. See Thorne M. Carpenter, ‘A Comparison of Methods for Determining the Respiratory Ex- change of Man,” Carnegie Institution Publica- tion No. 216,1915. One liter capacity, with dial divided into 1/100ths with each tenth division numbered. This scale can easily be read to one-half division or 5 cc. A horizon- tal line on the dial indicates the level to which the meter must be filled. The whole instrument can be immersed in water in ex- periments requiring uniformity of temperature throughout the meter and surrounding me- dium. As used inthe Nutrition Laboratory, Carnegie Institution of Washington. With spirit level, levelling screws and eG 6023 NotTE—Bohr Meters of larger capacity are supplied on special order. 2822 6024 2822. Gas Meter, Sargent. A wet test meter as generally used for both gas calorimetry and analysis. Made entirely of monel metal which results in great convenience and saving because of the absence of corrosion by laboratory fumes. The drum has four special shaped measuring compartments which enlarge as the gas coming through the inlet tubes displaces the water, thereby causing the drum to revolve letting the gas flow from the inside to the outside of the drum, which is so proportioned that it makes one revolution for each tenth of a foot of gas, or ten revolutions per foot of gas going through. As the porcelain dial is graduated into one hundred equal parts, each division will represent one- thousandth of a cubicfoot. The dial also has an hourly rate circle showing the amount of gas used per hour. Through a gear train the meter will integrate 100 cubic feet before repeating. With two permanent spirit levels, filling funnel, outlet cock, drain plug, gauge glass, syphon gauge, ther- mometer, and an electric switch which is left open until observations are started.......... 90.00 6024. Gas Meter, Laboratory. An ordinary five light gas service meter, modified by the removal of its lid and the addition of a dial and pointer to the main shaft. The dial is divided into one hundred parts and one revolution of the pointer corresponds to 3450 ml. The cubic feet dials of the meter are replaced by a single hand reading up to 16 revolutions of the main shaft. The meter is a portable and conveni- ent instrument for the measurement of gas flow or gas volume as, for instance, in measuring air flow in urea determinations by the aeration method, the measurement of gas volume in basal metabolism determinations by the Douglas bag method, etc. As delivered the probable error in the above ml equivalent per revolution is about one percent. As the velocity of gas flow increases, the metric equivalent decreases to be 0.7% less at a velocity of 35 revolutions per minute. The motion of the pointer around the dial is not quite even and the calibration curve for the main dial would involve corrections up to 220 ml for readings which are fractions of a revolution. The meter may be cali- brated to read within 0.2%. As used in the laboratories of the Henry Phipps Institute, Philadel- phia. See H. S. Newcomer, Journal of Biological Chemistry, August (1921). With special tubu- lations 1 inch diameter to fit the flexible corrugated tubing supplied in connection with the Douglas Dag es She aie ot ede tain cio Gh ee savene wena EM eRe ea Ooo RIDE Ame Te 35.00 6024a. Thermometer, for use in exit tube of above Meter for measuring the temperature of a gas passing through. Range 10° to 50° Cin 4°, recording in approximately 30 seconds............... 2.25 A complete laboratory outfit for the determination of calorie production and basal metabolic rate by the collection and analysis of a sample of expired air—the Douglas method with Newcomer modi- fication—is listed on page 367. The Benedict portable metabolism apparatus for the clinical measurement of basal metabolism by determination of oxygen consumption only is listed on page 368. 333 6030 6084 6030. Gas Pipette, Double Absorption, for Cuprous Chloride, Standard U. G.I. Form. This pipette was designed to replace the two double absorption pipettes otherwise necessary in making a gas analysis. By simply turning the cock it is possible to bring the gas in contact with the absorbent contained in either side of the pipette without disconnecting............0.0.0 0002 c cee ects 18.00 60312, “Glass: Rartsc only. fora DOV A. ek dics xses eosin cee See gs wish ai auth coed RA NBL ae eta rayaml dae! alas 12.00 GAS PIPETTES, HEMPEL, mounted on improved iron supports. The glass parts are fastened to the supports by means of adjustable metallic clamps with cork inset. The adjustment permits of the use of glass parts of slightly varying dimensions. To avoid breakage, iron supports and glass pipette are packed separately and must be set up in the laboratory. 6032. Gas Pipette, Hempel, simple absorption, for liquid reagents, on improved iron support........... 3.55 6033. Glass Parts only, for No. 6032 Gas Pipette... ..........0. 0. ccc cece eee eee et enees 2.20 6034. Gas Pipette, Hempel, simple absorption, for liquid and solid reagents. On improved iron support.. 3.85 6035. Glass Parts only, for No. 6034 Gas Pipette : 6036. Gas Pipette, Hempel, compound absorption, for liquid reagents, on improved iron support....... 5.00 6037. Glass Parts only, for No. 6036 Gas Pipette...... 000000 occ cece cect n ce nes 3.50 6038. Gas Pipette, Hempel, compound absorption, for liquid and solid reagents, on improved iron support 4.90 6039. Glass Parts only, for No. 6038 Gas Pipette..... 00.00.00 cece bcc ec ceceens 3.40 6040. Gas Pipette, Hempel, with glass beads for ethylene absorption, on improved iron support... ...,. 4.85 6041. Glass Parts only, for No. 6040 Gas Pipette 6044 6042. Gas nee Hempel, simple explosion, with stopcock and platinum “electrodes, on improved iron SUD DOL Ge xeiia syeen i tama! 2 as cect Marea ds Pap EEN et Sate OMAN ca gD al 8.35 6043. Glass Parts only, with platinum electrodes, for No. 6042 Gas Pipette 6044. Gas Pipette, Hempel, explosion, with platinum electrodes, stopcock and leveling bulb, on improved iron 11 7.00 support..... LER ET ee ee RN EOE aa Oy LORNA enema aan Peer ae ct te Mee nr ane Cena d .00 6045. Glass Parts only, with platinum electrodes, for No. 6044 Gas PIPE TLC Mey toes e meee Aes an Senay 7.00 6046. Gas Pipette, Hempel, with platinum spiral, for methane, mounted on improved iron support..... 7.85 334 6057. 6060. 6062. 6063. 6064. 6065. 6066. 6067. 6068. 5718. 5719. 5720. 6070. 6071. Sarl Peas DE etl} Ps PROVIDENCE.R.I 6065 6062 6067 5719 Gauge, Vacuum, of brass, with silver dial 3 inches diameter, graduated in inches to 30 inches of vacuum. Threaded to connect on }-inch i.p. thread........-.--- 0050. seers 5.50 Gauge, Pressure, of brass, with silver dial 3 inches diameter, graduated to read to 30 lbs. air pressure, otherwise identical with No. 6056............. 0. eee e cee ene ete nett eee n ees 5.50 Gauges, Wire, American Standard, of best tempered steel. 0 to 36 5 to 36 ie be ee aa ac tee ie ream ea eS elapse ts SoCo) Sin wane caer amet EG Lae eee ee esa ena ce eC ia rere eae osm t ea Ge 3.00 2.25 Glass Beads, hollow, 5 to 6 mm long by 4 to 5 mmin diameter. Per Ib............-.---.+55-> 2.25 3 4 5 6 PGE TB facies Ses eed sa ae eee Ge Foe aed gehen anaes eC a Glass Cutter, Diamond. A substantially mounted splint and guaranteed of satisfactory quality..... 5.75 Glass Cutter, with small steel wheel. A very practical tool. .......-. 2... eee eee eee ees 24 Glass Cutter Knife. A most convenient and satisfactory laboratory WEGNSILS oot aeons et ek etecnee .80 Glass Stirrers, with one end rounded and the other end pointed. Length, inches... ....-5e0s scene eed ee ees 5 i 8 10 12 15 Diameter, inches......------- +2 ests rere 5 is + 1 5 3 Per dozen: s2.3. hes Soe ea 30 .30 50 65 1.10 1.40 -mm diameter, with polished ends; as used in Vanier Combustion Train. .20 Glass Tubes, for use with Tube or Bomb Furnaces, with one end closed and with constriction for conven- jence in sealing off the open end. Of stout resistance tubing, more readily sealed than No. 5720 and sufficiently hard for most purposes. Length of tube to constriction, MM.......-..- 0.2 seers 415 500 615 Depa GeR Pie os ok ee ves eee Ea AS eae Died 18. 20 22 -40 45 50 Glass Red, 12 inches long, 12 Glass Tube, for Carius Furnace No. 5717, 24 inches long by 1 inch outside diameter, with }-inch wall, and with one end sealed. Of ordinary lime glass for use at ordinary temperatures...........- 70 ditto, but of Pyrex glass, for use at high temperatures... 6.0.00. 0 eee eee ete teen nee 1.60 Will cut tubes from ;3; to 1} inches diameter. 6.65 Glass Tubing Cutter, for attaching to laboratory table. 95 Wiccel only, cor ND. 00 Dubing CUtlen...pexca ci ayes seine Semen ae ere ee esate oes Sees 335 wr) 6074 6072. Glass Tubing Cutter. Large size, will cut tubing of 2 to 1 inch in diameter in lengths up to 8 inches; small size will cut tubing 3 inch in diameter in lengths up to 5 inches. SIZ Cie ae ec ora pate No Sac se Wc aR 18 cca aan ota tear ite felttn tS AeA eect gS Nee Ns oa Small Large PG hice) os ieee, Bet et cA ek ate Doct Ser ot a rece ty sl (AT vtec toch tO A ce Nhe Bed See ae Bera 1.10 1.10 6073; “Cutter: Wheels, only-. “Reridozeniyc0c. oe.52 hoe be exe ok Sede i ee dG he ders we 1.60 6074. Glass Tubing Cutter, Griffin. ‘Mor tubes;mmisin: dianieter..a3 we ne hoe Oe ee ey Ge Ba ek haw 17 30 GACH Ce cece rt ea eRe ARCS eee tas rane tes ate eee Ne aS PRON Patan nt oem Dy 1.20 6075: “Wheel;--only,. tor Gritinc@ otter: 5 32. oe ccs neces Banca hate | Wun AL cok et lee puree bcehal veils .20 6076. Glass Tubing Gauge, of steel, very convenient for rapidly sorting glass or metal tubing by outside diameters. The slots vary in width by } mm. Size,mm...... Ae Uren en AeA § 1to5 5toll 11to16 EA GIN Ae Bs PRA ene oe Ril a nibs de Baek as Pd tat Nh eS LON R 1.00 1.25 1.50 Glass Wool; of spur classi> Grade i202 7.25 2a .aeecrct aio gane aoe Sone add Bice aee oh a eau av ie Fine Coarse POR HOLM CATE OM acon us ocr ae eee aimee RY ese th ae hrand A Sonny usenet arate seeped ewe .30 30 ee tid © Sioa 0 ge ola he eet nrats Lasse aE oN ca ae ATeager ik ath coe, Nae ee aru a ha eld Ta 85 -80 Spe La ack em ats a eaat decade trac eg eee wae wies a aeah ct t PONe eaten ght ae onde Shree ap et tae 2.95 2.60 GLASS TUBING AND ROD SELECTION AND SORTING. Ourselection of tubing and rod for working before the lamp in the labora- tory is carried in stock in original factory lengths of about 5 ft. As the factory selection and packing is mostly unsuit- able for laboratory purposes, all our tubing and rod are regauged and repacked in our own establishment. In gauging the tubing, the measurement is made at the middle of the piece to within the tolerance given in the following table, but customers are reminded that some variation between the measurements at each end must be expected, and that tubing or rod selected for uniformity throughout the length of the piece and to an actual measurement requires much additional sorting and must, therefore, be sold at much higher prices. The tolerances to which our tubing is gauged before placing in our stock are as follows: 8 UO: 9 MIM ANCIUISIVEs sce 5 rica: anise eae a eae Barat aaiRGa Susteee Veda Aan + 3¢mm LQ sang AAs rns eis ee aes PSD Clie AL to Mee se aehe dene + ilmm R518, 20 clo A Os Zo TINS cei cote tesa gee eens Gophed noth ten ened panensesinvin Ratob deltas + 14mm 30:35; 40. A5-and 50 MMe. esc ais ss ast Hivsh den 3 aug olang cused woMeoeee eer ee + 24mm Tubing for satisfactory manipulation before the lamp must have a moderately thick wall, and much tubing is drawn for the manufacture of homeo vials and other purposes with a wall entirely too thin for laboratory manipulation in the manufacture of apparatus. Glass tubing should always be specified by outside diameter (unless it is to be specially selected as to acess involving an extra charge), with the exception of combustion tubing where approximate thickness of wall is given. All glass tubing—except very small quantities which are cut and packed in case with other goods—is shipped in specially made boxes, for which an extra charge is made. = = = = nn au £ & MM 8MM 2 = © 2 é a = s6000 000 6080. Smaller sizes (actual size) 6080. Glass Tubing, Bending. A lime-glass tube of suitable wall for convenient and easy manipulation before the lamp in the manufacture of apparatus. The measurements given are all outside, and the tubing is selected in accordance with tolerances given in the preceding paragraphs. Outside diameter smints hey. aii As, yaw cnecomee eine enon 3to4% 5to30 31to 38 39 to 50 Per Ib., in factory lengths of 5 ft., boxing extra........... .80 50 56 .90 10% discount in 25-lb. lots. 20% discount in 100-lb. lots. 336 30mm 6080. Larger sizes (actual size) (For description and prices see page 336) _, GLASS TUBING, PYREX G-702-EJ, of the same composition as Pyrex chemical glassware. This tubing is furnished in original factory lengths of three feet, in both light and standard wall. Itisa very hard tubing and its manipulation before the lamp requires some experience and a hot flame as Pyrex glass does not begin to soften under about 750° C. It is recommended for all laboratory uses where sudden changes of temperature, reaction of acids and alkalies are to be resisted, and where mechanical strength is necessary. The average thickness of wall in the light wall tubing is about 0.6 mm in the small sizes to 1.2 mm in the larger sizes; while the standard wall varies from about 1.2 mm in the small sizes to about 2.4 mm in the larger sizes. The light wall tubing is suitable for the manu- facture of conductivity cells and similar apparatus, while the standard wall is reeommended for general laboratory purposes. The selection and sorting is made within the tolerances previously described. 6081. Glass Tubing, Pyrex G-702-EJ, as above described, light wall. Outside diameter,mm....................... 4 6 8) 102 12 215 9B 22> 25 Per Ib., in 3 ft. lengths, boxing extra........... 2.00 2.00 1.80 1.60 1.60 1.80 1.80 1.92 1.92 6082. ditto, but standard wall. Outside diameter,mm............. 10 12 15 18 20 22 25 30 35 40 45 50 Per Ib., in 3 ft. lengths, boxing extra. .80 .80 .90 .90 .90 .96 .96 .96 1.10 1.36 1.36 1.66 6084. Combustion Tubing, “M. J. V.” This is the hardest glass now obtainable and is specially made for com- bustion. It begins to soften at 800° C, and is furnished in original factory lengths of 40 inches in the sizes listed below. Outside diameter,mm..................... 6 8 9 18 20 25 Inside diameter,mm...................... 4-5 6 63-7 15 18 21-213 Per Ib, boxing extras<:.0.6 04: sacks oes caved 2.00 2.00 2.00 2.00 2.00 2.00 6086. Glass Tubing, Barometer. This is mostly furnished with bore between 1.5 and 2 mm in five diameters as listed below. In original factory lengths of five feet. Outside-diameter; mms 256 o5-62-6 hes eee ee ee ce 6 8 9 10 11 Perl by DOXINSEXtra ss becca tasks ss nae ae ncn aes Sees 85 .85 .85 .85 85 6088. Glass Tubing, Capillary, with very small outside diameters. The 2 mm tubing has a capillary fine enough to be designated as thermometer tubing. The tubing of 3, 4 and 5 mm outside diameter has a bore of about 1 mm, and differs from barometer tubing only in the outside diameter. Qutside:diameter, MMs 64: .2< greene Gonchos wwf heels Syed Mae thedls bane 2 3 4 5 Perlb: boxingiextras. cies ek chia ap ee A ale iat areal we ee -80 .80 .80 .80 6090. Glass Rod, Bending, of a lime glass of the same composition as our No. 6080 tubing, for easy manipulation before the lamp. This rod is sorted, selected and packed within the same tolerances as glass tubing, and is carried in stock in the following sizes, in original factory lengths of five feet. Diameters Mmm shane es Sa ee eee ek 8to9 10 12 15 18 20 22 25 Per Ib., DOxiNng CXtra . ees ee els enh hee aie aes 48 .36 .36 .50 .50 .60 .60 .60 10% discount in 25-lb. lots. 20% discount in 100-lb. lots. 6092. Glass Rod, Fusing, Corning. A soft glass rod specially made for the fusing-in of platinum terminals; usually designated as “‘sealing-in”’ glass. In 36-inch lengths of approximately ;-inch diameter. Glass Rod, Colored, of suitable dimensions and colors for the mounting of anatomical specimens in museum jars, and for making stirring rods in the laboratory where stirrers of different colors are found convenient for easy identification. The designations of the colors are those used in technical factory control and, as they do not always convey an accurate idea of the appearance, we explain them as follows:— Amber—semi-transparent, very light brown Blue—black, i. e., the blue is so dense as to give the effect of black Copper Ruby—opaque dark red Gold Ruby—semi-transparent, dark wine color Opal—opaque white Turquoise—opaque light blue This rod is carried in stock in only two dimensions, and is furnished in factory lengths of three feet only. 6094. Glass Rod, Colored, as above described, ;%;-inch diameter. CO oer etg ak REE eee SE OSS Amber Blue Copper Ruby Gold Ruby Opal Turquoise Per 3=ft lengths ive osce ee ee ans.4 .25 .25 -60 1.50 .25 .25 é ditto, but 41-inch diameter. ae Bor Sit lene ac cee bees 45 AB 1.00 2.50 45 AS 6100. 6101. 6102. 6104. 6105. 6110. HH! i I A ee 6100 6102 6104 6105 Glue Tester, Alexander, for determination of viscosity of glue. A special 45-ml volumetric pipette sup- ported in the center of a water bath with heating wing. Complete with tripod............ 9.00 Pipette only; for: Alexander*Glue: Testers: .3. geen Ae es ee sd he eet oe obo eee ees 2.00 Glue Tester, Scott, for testing the tensile strength of glue, gelatin, etc., and for making comparative tests of the hardness of greases, wax, etc., automatically reading in pounds and fractions of ounces.. 27.50 Goggles, Cover’s Patent. Widely used in the chemical industry, and in laboratories were there is exposure to fumes, gases, dust, etc., which may injure the eyes; with lenses of clear glass easily removable and mounted in soft rubber which fits closely against forehead and face.................. 1.50 Goggles, of blue glass, with heavy metallic spectacle frame.................. 0.0.00 ..0 000000 1.50 Goniometer, Penfield, Application, pocket form............ 00.0000 eee -50 GONIOMETERS. The Smith Reflecting Goniometer and large two-circle Reflecting Goniometer of the Goldschmidt type of either American or European make are supplied on special order. 6112. 6113. 6114. 6115. 61138 6115 Graduates, Glass, Acme Brand, Metric, flat bottom without foot, with principal graduations extending around the glass, readings to be made at the bottom of the meniscus. These graduations are in accordance with the Revised Edition of the Pharmacopeeia, and Bureau of Standards specifications, and comply with the laws in all States. Capacity, ml................. 250 500 1000 Bachan Seca actrees ie SG DR See ete Bilge Bt Glee race Gata laeeea ag telA 1.05 1.35 1.90 Graduates, Glass, Acme Brand, Duplex, exactly the same as No. 6112, but with both metric and apothe- cary fluid measure graduations. Capacity, ml........ 60 120 250 500 1000 Capacity cOUNCESs, Gesiiy sane ili Gatun tt aes 4 sion eeae 2 4 8 16 32 BELA CMpreeedace ta ol cts sto serene chal eos ca eae eee le ae ae 1.00 1.35 1.50 1.90 2.80 Graduates, Glass, Phenix Brand, Metric, cone shape with foot, with principal graduations extending around the glass; readings to be made at the bottom of the meniscus. These graduations are in accor- dance with the Revised Edition of the Pharmacopceia, and Bureau of Standards specifications, and comply with the lawsin all States. Capacity,ml. 30 60 120 250 500 1000 GACH sey av stasc So ays ae net Lk aa eee eR ert 75 .80 1.00 1.15 1.65 2.55 _. NoTE.—We have discontinued the sale of lower priced Graduates than those above listed because of non-compliance with many State requirements as to accuracy in such utensils. Graduate, Glass, with handle and with metric graduations as shown in illustration; capacity, 1500 ml. 1.50 338 6116. 6117. 6118. 6120. 6121. 6124. 6125. 6128. 6117 Graduates, of heavy glass with handle, graduated in ounces. Very convenient in the laboratory for handling of acids, etc. CAM ACIE VEY OUT COS 5 ecicce cca ce tcc a tit ee Pane ho vara OM eee sy NA 32 64 ACID ie aoc ak aerve eek toopvar euch cuenta mer tA a tect aed oo phes on oe Morals ane Malaat We Gee aRtopca sty Ot Ute Rt 1.35 3.35 Graduate, glass, with graduated stem, as used in moisture testing in wood that has been creosoted, etc. Stem is graduated to 12 mlin 1/10ths. See Bulletin No. 134 of the U.S. Department of Agriculture, TROT ESt SC LU UC en acini ten sri aie rate pea at ga A et te Nan eto, ie ak AP ace RN ocak 1.80 Graduates, Aseptic Enamel Ware, of seamless steel, white enameled, both acid and fireproof. Graduated on the inside in grams and ounces. Capacity OUNCES i.e nie sie ies GHelg et jour emanate NEN Sree Roy FeO 16 32 64 Capacity sioramsctece- chee tan tis oA a ating Olle kms aura Ges held bua le Sed 500 1000 2000 ACH as hea eras ee ees qe Seu de Gad ME Ses oe BAAN Se REN age eo Be 1.60 2.30 3.25 Hammers, Geologist’s, solid cast steel with edge parallel to handle. Convenient for breaking ores in the laboratory. Weight, OUnC6S:. 0.5. <4 c.6 sce apa ease ata a moses emweoe a eae 14 20 28 RCH ge ho se teecs usp de OR wos Seas det A desea Sees Cs ete meatl bs ek NS Rea eed Nace trae 1.35 1.60 1.85 Hammers, Geologist’s, solid cast steel with edge at right angle to handle. Convenient for breaking ores in the laboratory. Weight, ounces.................. 20000 e eevee eee 8 12 16 AVC Wises te sues ets os tah cast Sec ee RACE GRATE Weed CA vce UID oe A re ap cee Sra 1.40 1.50 1.50 Hardness Tester (Scleroscope), Shore Model C, for measuring the hardness of metals. The essential part of the instrument is a hard steel hammer with a properly formed diamond at its striking end, which is allowed to drop upon the surface of the metal under test. After striking and indenting the metal, the hammer rebounds, and in amount proportional to the hardness of the metal, which is read direct on the scale. The action is pneumatic. When the rubber bulb is pressed and released the hammer is drawn by suction to its uppermost position, where it is held by mechanical means. The next pressing of the bulb releases the hammer, which drops to the work—unimpeded because during its descent the glass tube is wide open at top and bottom. The illustration shows the instru- ment in self-contained form, as it is used for measuring the hardness of thin, flat pieces. By operating the double ball handle at the rear, the work is clamped between the scleroscope proper and the anvil. The suspended leveling rod at the right of the scale, the leveling screws, and the magnifying lens are self-explanatory. The outfit consists of the scleroscope proper as shown in the illustration, with a swinging arm stand for pieces that can not be laid on the flat surface of the anvil, with plaster mount vessel for holding odd shaped objects, magnifier hammer with a larger point for use on very soft metals, a soft steel reference bar, a hard steel reference bar, fifty blank curve charts and a book containing full instructions and a treatise on the hardness of metals and their measurement, all in polished hardwood case. ............0.0 000 cc ee 225.00 dittombut= with-clock: ial. 4 Wb 08 ie i than sc canomne as neweerhc cya tacse hood ae ea Seas See She, a eee setae 250.00 Microscope, Brinnell, for the accurate measurement of impressions made in the Brinnell ball test; con- sisting of a body tube on a circular base with 10-mm aperture for viewing the specimen. The interior of the body tube surrounding the cut-out portion is finished in white to increase the illumina- tion of the specimen. Sliding in the body tube is a focusing tube carrying a Ramsden ocular and 32-mm achromatic objective. When the focus is obtained the focusing tube may be clamped by means of the ring shown in the illustration. The tube is fitted with a 7-mm micrometer disc, graduated in tenths of a millimeter with every millimeter line longer than the rest and numbered. The:ocular is focused: upon this: ise. .cg.sc6os ¢ aevsoe ss caeee ea pea he ORE Se ea dea Dee oles 35.00 A UR “THe UR H. T H O M AS Cc O M P A N Y ELECTRIC HEATERS | | ul Ez HEATER, GILMER PATENT ELECTRIC (Licensed under Marsh Patent No. 811,859). The cover and base plates are made of asbestos cement, which is not attacked by acid fumes and solutions. These two parts interlock in a way to prevent side slipping, yet they can be taken apart instantly without the removal of a single screw or bolt. The cover plate contains a circular opening 32 inches diameter at the top and 23 inches just over the heating unit. This opening fits exactly an 800-ml Kjeldahl flask. The base plate is mounted on 1-inch legs. The resistance wire is of nickel chromium alloy highly resistant to acid and alkali. It needs only to be washed with tap water before re-use, should a flask of boiling sulphuric acid break. The wire is wound on the plate in such a manner as to place the resulting heat directly under the flask or beaker in the smallest possible area. The heating unit plate is formed of acid and heat resisting porcelain and will average many rewindings before breaking. The assembled stove measures 6 inches long by 5 inches wide by 33 inches high. Heaters are carried in stock wired for 55 volts and for 110 volts. For single installation we recommend 110-volt heaters. On battery installations, as required for nitrogen determinations and similar work where groups of heaters are in constant use, connecting stoves in series of two or more is 2 most economical and convenient method. For example, if the voltage is 110, two 55-volt heaters are connected together and then to the main or feeder wire. If the circuit is 220 volts, either two 110-volt heaters or four 55-volt heaters are connected in series. Each heater uses approximately 400 watts. An 800-ml flask containing 450 ml of water will be boiled and 250 ml distilled over inside of 60 minutes. The average life of a heating element under strenuous working conditions is approximately 1000 working hours, but with care elements have lasted over 3000 working hours. This heater was designed primarily for battery installation in the Kjeldahl Ammonia Determination for both digestion and distillation and is furnished with our complete outfits for this purpose. See Nitrogen Determi- nation Apparatus, page 444. During the digestion period the heat is even and constant, requiring no watching for frothing or shaking of flask to remove particles or samples from the sides as with gas. The high temperature attained after 15 minutes from start gives an even, brisk boil to the acid, with subsequent rapid oxidation. The time on each batch of determinations and for each flask of the batch is always the same, allowing systematic arrange- ment of work, an impossibility where gas flames have to be constantly adjusted and the usual waiting for one or two flasks from each batch because of poor flames. In the distillation of ammonia determinations the same features are even more strongly emphasized. The heaters are not affected by draughts of air. The heat can not be blown out with the resultant ‘‘sucking back.’’ The distillation is even and has less ‘“‘spurting.’’ With both periods of the work the heat is controlled with one snap of the switch. With the Gilmer heater, flasks are only rinsed before re-use. Washing is unnecessary as there is no grime and soot common to all gas flames. While the heater is designed for Kjeldahl determinations, its use is by no means limited to such work. With its circular opening and flat top, 5 x 6 inches, the heater readily adapts itself to wide uses. The heat can be varied by the location of the vessel, from 800° C for incineration to the slow simmering heat of a hot plate. The circular opening and flat surface will take all the common laboratory vessels, Kjeldahl flasks, evaporating dishes up to 2500-ml capacity, crucible, boiling flasks and beakers. With the addition of the metal top, the heater makes an excellent hot plate suitable for potash determinations (evaporation, digestion and incineration), incinera- tion of coals, water analysis, phosphoric acid determinations (digestion of samples and incineration of insolubles), ash determinations and many other common laboratory analyses. C il | 6130 6131 6136 M HH i | | tt 6130. Heater, Gilmer Patent Electric, as above described, without metal top. For volts..... 55 110 Bach COmplet Cre: d ae deec uso eot sats wey ua. Ou ete se PS aks Mendes ne lye aan oe 5.00 5.00 6131. Heater, Gilmer Patent Electric, with metal top for use as hot plate................... 6.00 6.00 Gl32e) SM etalon, onlyiess oe skh AR ere au auc ene eee Neg e a oe ante paves ey ace 1.00 1.00 Glas ‘Healing Unites: occ ore ee ed el a a ee a ate nti emilee sone 1.50 1.50 6134; -Rewinding heating Unite. 0532) ete deoe eon ic wad pela noes pay se i es 1.25 1.25 6135s, Cover Plater. 5.38 Fins coe Nee ee ers nought enn Rant me Map dan ch sla ea hha on 1.60 1.60 G18G%. “Base:Plate dos gcd ncn ae atest See Nee Us Veen a he ate ae ine ep ate ae Ses 1.90 1.90 6138 6142. Fig. 1 6142. Fig. 2 HEATER, CENCO ELECTRIC, designed expressly for use in the distillation of gasoline with outfits such as No 7624, but also suitable for a variety of other purposes. The spiral heating coil of nichrome wire is inserted in a conical spiral groove turned by means of a specially constructed machine in a solid block of insulating material. The separate turns of wire are in contact with the insulating block for only a small part of their circumference and, as a result, practically no heat is wasted by absorption in the block. The conical shape of the depression in the block, combined with the high heat-radiating qualities of that material, causes practically all of the heat to be focused upon the 1{-inch opening in the transite top of the heater. Asa result, the flask containing the gasoline is subjected to an intense heat (sufficient to ignite paper immediately) without the danger of breakage due to con- tact with a bare flame or a red hot coil. The coil of heating wire, together with the grooved block in which it is inserted, constitutes the heating unit, which can be easily replaced by the user in case of a burn-out. A variable rheostat is mounted in thesame case with the heating coil, permitting the temperature to be raised or lowered at will. The heater is furnished with a clamp, permitting it to be mounted on any laboratory support stand. Many uses will be found for this device in the laboratory, as it furnishes a rapid and efficient source of concen- trated heat which will be found preferable to a gas flame for many operations. See: Technical Papers Nos. 166 and 214 of the Bureau of Mines, Motor Gasoline, Properties, Laboratory Methods of Testing and Practical Specifications, by E. W. Dean; Bulletin No. 125 of the Bureau of Mines, The Analy- tical Distillation of Petroleum, by W. F. Rittman and E. W. Dean; The Journal of Industrial and Engineering Chemistry, 10: 10, p. 823, A Convenient Electrical Heater for Use in the Analytical Distillation of Gasoline by E. W. Dean and Standards of the American Society for Testing Materials for 1918, No. D-28-17, pages 606-609, Standard Tests for Paint Thinners Other Than Turpentine. 6138. Heater, Cenco Electric, as above described, for 110 volts, with 6-ft. cord and plug for attachment to any WAM p:SOCKCb ite tev ses ects Goes caste nme bee aln animals asPMners Bits, Minka ny fumni, banuen dain yi amurahe Ns 4 17.50 6139. Gitton but or 220 Volts see sap sue aces soe ve norets g 4 Necre he aot tho cpa meh ee ae Ee ca ea Sis oh hee 18.50 6140. Heating Unit only, for Cenco Electric Heaters. For volts........................0.. 110 220 RO assets 5: eas sts case ered aes b adinte PRN g Ea cance a hse ap ERG Ea A mG PENSE Shania eae gael Seas 5.00 5.00 HEATER, UNIVERSAL ELECTRIC. A new and patented principle is employed whereby the heat is concentrated at the upper and central portion of the heater, by radiation and convection, the heated air striking and surrounding the object to be heated. Crucibles and test tubes are so placed within the heater that they are heated on the sides and bottom by direct radiation. For heating round bottom glassware and porcelain this arrangement is ideal. The construction is simple and durable. The heating coils are so arranged that any liquid spilled upon the heater falls through without injury to them. The current consumption at 110 volts is 6.8 amperes on high and 4 amperes on low. i ‘ , ree ; In operation the switch is turned to high until the apparatus is hot, after which it may be adjusted to the temperature desired. When the heater is to be used continuously for a long period, it is advisable to place it on an asbestos pad to protect the table. The illustration shows a flask being heated. The attachment there shown furnishes a support for flasks or evaporating dishes, and also serves to protect the heated object from cold air currents. For igniting filter papers and precipitates, and determining volatile matter and ash in coal, an asbestos plate should be loosely placed over the top. 341 Ac SR ok CH SW oR H. T H OO M A 5 C O M P A N_ Y UNIVERSAL ELECTRIC HEATER (Continued) Attachment A, Fig. 2, inserted in the heater from the top, will hold from one to four test tubes. The gauze B is of special form for the support of round bottom flasks and evaporating dishes, and is placed in the top of the heater together with the device shown in Fig. 1. Beakers and other flat-bottom apparatus are heated in a similar manner, using the flat gauze C. The nichrome triangle D, inserted in the top of the heater, supports crucibles in position to receive the most intense heat. After heating until there is no danger of the paper blazing, the attachment shown in Fig. 1 is used, and the whole loosely covered with an asbestos plate. This arrangement furnishes sufficient heat to ignite precipitates, the gases escaping around the asbestos plate. The same arrange- ment is used for determining the volatile matter and ash in coal. For reduction experiments, attachment E is placed over the heater, the reduction tube allowed to rest in the slots, and the asbestos plate placed over the top. Copper oxide is thus readily reduced by hydrogen. By placing attachment F over the flask shown in Fig. 1, the heat is conserved and the time of boiling or distillation very much reduced. The use of this device is necessary in the distillation of water according to the specifications of the American Public Health Association, in order that the first 50 ml may be distilled over in the required time. 6142. Heater, Universal Electric, as described above, with attachments A, B and C, for 110 volts.... 18.00 6143. 3° 2° ze 1 1 1 1° Hache k aon cee ee es ee a 1.00 1.00 1.00 1.00 1.00 1.00 1.00 10% discount in lots of 12. A HU OR H. T H O M A S G-- OS Mis Ri A. tN: By 6200. 6201. 6202. 6203. 6204. 6205. 6206. ditto, but with Bureau of Standards certificate. Per set Hydrometers, Brix. Approximate total length 11 inches, length of graduated scale 4} inches. Take a cylinder 300 x 40 mm, and require 225 ml of liquid for submersion. Graduated to }°. S Cal sire og. tors cairn vad ee ret conan Eay sod ae PAO sor eld inch em epeanrte eagteG eee 0-30 30-60 60-90 GACH ree ai eect treads, Geer de eas toe we a Wee at aman toc eps A A Lares Laven Ee tee REAR art 1.60 1.60 1.60 10°% discount in lots of 12. Hydrometers, Brix, calibrated at 173° C., for use in the sugar industry. Accurate to }° Brix, i.e. two scale divisions. Approximate total length 12 inches. Take a cylinder 300 x 40 mm, and require 225 ml of liquid for submersion. SCalesay tee se eiaears nea : 0-10 10-20 20-30 30-40 40-50 50-60 60-70 Graduatedto....... ane qn? va Tn te ts on Each.... ihe: 1.75 1.75 1.75 1.75 1.75 1.75 1.75 10% discount in lots of 12. €! Sse) Se STS AMT .CO. 6202 Hydrometers, Brix Precision, calibrated at 174° C. These Hydrometers correspond with requirements of the Bureau of Standards in that all divisions must be at least 1 mm apart, and accuracy is guaranteed to within a tolerance of + 5°. Intended for the most exacting requirements of the sugar industry. Approximate total length 12 inches. Take a cylinder 300 x 40 mm, and require 225 ml of liquid for submersion. Scales. 25 outed ean 0-10 10-20 20-30 30-40 40-50 50-60 60-70 Graduated to.................. : is” ts? wh? aie aise ds? ah? ACI conchae tike et ae O00 eet RAS eeracn on 3.50 3.50 3.50 3.50 3.50 3.50 3.50 10% discount in lots of 12. ditto, but with thermometer. S calem: cores dik a ciiediebated Peciedens 0-10 10-20 20-30 30-40 40-50 50-60 60-70 Graduated to................. : Tae as? ty qh” sine a5? a? Bach osciiauniesd ade casemate: Mae 7.00 7.00 7.00 7.00 7.00 7.00 7.00 10°% discount in lots of 12. Hydrometers, Specific Gravity, Precision, reading to between the third and fourth decimal place. Approx- imate total length 13 inches, length of graduated scale 5 inches. Take a cylinder 350 x 50 mm, and require 500 ml of liquid for submersion. Scallen vf. Gio le ey pi oe 0.700-0.760 0.760-0.820 0.820-0.880 0.880-0.940 0.940-1.000 Graduatedto...... ~s .001 .001 -001 .001 -001 Bache 3 hes aaa 2.70 2.70 2.70 2.70 2.70 Seale .. ae . 1.000-1.060 1.060-1.120 1.120-1.180 1.180-1.240 1.240-1.300 Graduated to ... i .001 -001 -001 .001 .001 Baehi sent oa ee oh 2.70 2.70 2.70 2.70 2.70 Scales tanecwseses _ 1.300-1.360 1.360-1.420 1.420-1.480 1.480-1.540 1.540-1.600 Graduatedto............ 001 001 001 .001 001 Bach: 3 32255. e: 2.70 2.70 2.70 2.70 2.70 SCAT ES i. nce. 2, ea eevee . 1.600-1.660 1.660-1.720 1.720-1.780 1.780-1.840 1.840-1.950 Graduated to..... Bi at Nyse -001 -001 -001 -001 .001 Bach’. Secekae.s eee sass 2.70 2.70 2.70 2.70 2.70 6205 Hydrometers, Precision, reading in specific gravity to the third decimal place. In imitation leather covered case. Approximate total length 9 inches, length of graduated scale 33 inches. Take a cylinder 250 x 40 mm, and require 175 ml of liquid for submersion. Set of 8 covering range 0.700 to 2.000, graduated to. 002. With separate thermometer 0° to 120° F, in 1° divisions. Ranges are: 0.700-0.800 0.900-1.000 1.200-1.400 1.600-1.800 0.800-0.900 1.000-1.200 1.400-1.600 1.800-2.000 OTIS OUR. Nois a coon eroice roe eet nd reader RE eed oe OLY nn ALA RY ne) aes ate weet Set Ok Cie wea 26.50 Note—Spindles are not sold separately. NatE—Spindles are not sold separately. 348 A R T H U_R H. T H O M A 8 ¢ OO M P A N Y 6207. Hydrometer, Alcohol, Tralle and Proof Scales, reading from 100° below to 100° above Proof in 2° divisions and from 0 to 100° Tralle in 1° divisions. Approximate total length 12 inches, length of graduated _ scale6inches. Takes a cylinder 300 x 40 mm, and requires 225 ml of liquid forsubmersion... 1.60 6208. ditto, but with enclosed thermometer., U. S. Custom House standard pattern. Approximate total length 15 inches, length of graduated scale 6 inches. Takes a cylinder 375 x 50 mm, and requires (530ml of liquid:forsubmersioni.2 4 cy son sence ae na) aut eae yuan iioa ns ba eee 4.50 6209. Hydrometers, Alcohol, U. S. Internal Revenue Bureau Pattern, covering the entire range of spirituous liquors. Approximate total length 9 inches, length of graduated scale 33 inches. Take a cylinder 250 x 40 mm, and require 175 ml of liquid for submersion. IN UMD Tapes cok ket ean ec es tars Tit hen ema: ys : 1 2 3 4 5 Seales... c.cu24 Sete b aroha ne wu Ue nak RNC 0-100 80-120 100-140 130-170 160-200 Graduated to... . ee Pie a inane hea z° 4° ao x" a Each....... 8 Gs ee woe yh Gna age a eet er sae stad 2.59 2.50 2.50 2.50 2.50 6220 6210. Hydrometers, Alcohol, for testing alcohol in museum jars and biological work without the inconvenience of pouring off a sufficient quantity to float the usual large hydrometer. Set of three hydrometers covering range from 30 to 100% volume. Approximate total length 3} inches, length of graduated scale from } toljinch. Take a cylinder 100 x 25 mm, and require 35 ml of liquid for submersion. Persetin: Cas@ in, eure Gers WO ewer scene rare Ree Aaa aan ee een ie ren eee eee 8.60 6212. Hydrometer, Ammonia, 35-10° Baume scale, graduated to 4°. Approximate total length 10 inches, length of graduated scale 4 inches. Takes a cylinder 250 x 40 mm, and requires 200 ml of liquid FOTSUDMersi Ole toss eorenen ee eee errant oP N te eel anaes tee Gece NEUEN Ma oye one 1.30 6214. Hydrometers (Barkometers), graduated in Barkometer scale at 60° F. Approximate total length 12 inches, length of graduated scale 5 inches. Take a cylinder 300 x 40 mm, and require 225 ml of liquid for submersion. SCale steno tint cram ea ner ye ee ual kk CA ee ne Ee 0-60 0-120 Graduated to......... : f ile 8 Babe 12 1° Wa Ghirecore nino) a aac eterna) sea ee aero ad een ear vee oneal ese iene Oe : ee oe 1.70 1.70 10% discount in lots of 12. 6215. Hydrometers (Barkometers), with enclosed thermometer reading from 30-120° F, in 2° divisions. Ap- proximate total length 13 inches. Take a cylinder 350 x 50 mm, and require 500 ml of liquid for submersion. SCalet sop Aan rk cites Suet ton a aa ese: I aera ee Pee Ta ssttaset in Td ach INP Ai ae 0-60 0-120 Graduated to.................0.. : ee ee ; a 1 Length of graduated scale, inches.......... nmi bes ioe we 33 43 AC ne area rat ag en ree oe, Nerd Sct EOE ne Se a Seam de Oy MER tn rc ReLeN Sez Aah ih ees 5.00 5.00 6216. Hydrometer, Lime-Sulphur, for use in determining the degree of density of lime-sulphur solutions as rec- ommended by Parrott and Stewart. Graduated 0-38° Baume and 1.000-1.350 specific gravity. Approximate total length 10 inches, length of graduated scale 44 inches. Takes a cylinder 250 x 40 mm, and requires 200 ml of liquid for submersion...............0 000000000 eee ee 1.89 10% discount in lots of 12. 6217. Hydrometer, Baume, for Petroleum Oils, graduated 70-10° in 1°. With enclosed thermometer graduated 0-120° F, and correction scale. According to the U.S. Petroleum Association. Approximate total length 14 inches, length of graduated scale 5} inches. Takes a cylinder 350 x 50 mm, and requires 550: mbhof liquid forisubmiersionc gape sd-yenpetqeav eves eae cues tuk od, wee ee AE, GE RS 5.00 10% discount in lots of 12. 6218. Hydrometer (Salinometer), for direct reading in percentage of salt content. Range from 0 to 100% in 1% divisions. Approximate total length 11 inches, length of graduated scale 43 inches. Takes a cylinder 250 x 40 mm, and requires 200 ml of liquid for submersion. ....................... 1.30 6219. Hydrometer, Storage Battery, with specific gravity scale 1.00-1.300. Approximate total length 7 inches, length of graduated scale 2} inches. Takes a cylinder 150 x 25 mm, and requires 75 ml of liquid for SUDMELSION se pes ses oat anes et oe bi bons eee MeN ae hacen tandem tl tenet ada sneer teas ape Leer tiehoue Mant gar 1.20 6220. Hydrometer, Storage Battery, with syringe and printed scale. The pointed tube of the syringe is inserted in the storage cell opening and the electrolyte withdrawn by means of the bulb. The specific gravity is then read by the hydrometer floating in the cylinder of the syringe without the use of another container. Reading from 1175 equals total exhaust of battery; to 1300 equals full CHAR GOs ccs se shet nis are aera at a eel Behe acta Dan eeu aes eget Sate ean cringe a a Nene i haaeg. ote Ya eee teks 1.50 6222. Hydrometer, Sugar and Syrup (Sweet Water Spindle), Brix scale — 5° to + 5° in 7 divisions. Approximate total length 12 inches, length of graduated scale 43 inches. Takes a cylinder 300 x 40 mm, and re- quires 200 ml of liquid for submersion... ........... 0000 eee eee 1.50 A R T H U R H. T H O M A _ S G0. (Me PA UN UY 6223. Hydrometers, Sugar and Syrup, Baume scale graduated to 1°. The 0-20 hydrometer takes a cylinder 250 x 40 mm and requires 200 ml of liquid for submersion, while the 0-50 takes a cylinder 300 x 40 mm and requires 225 ml of liquid for submersion. Send Gras teeta aneel ence me Oy er enc See aR Ne lets ten teres ap ah agree. ee ean 0-20 0-50 Approximate total length, inches............... 00000 e eects 8 11 Length of graduated ‘scale, inchesy, «5. ¢0:4.ca cea es Aaa ashaacele e Giect eons Ae a elses a 2 4 BAC Hee een Bh cen ees ee at er a eee cove Oo aus al isande Seige dese ree os mash aR tee a de 1.25 1.25 10% discount in lots of 12. 1354. Hydrometers, Specific Gravity, for liquids lighter than water. Approximate total length 9 inches, length of graduated scale 3} inches. Takes a cylinder 250 x 40 mm, and requires 200 ml of liquid for sub- mersion. As used in Barrett Test E-2. SCAG st hex Se Arch roth coh ons alegre a atnt enon aig Ghceag tases eae 0.790-0.870 0.860-0.940 0.930-1.010 Graduated (02 wcs conor hence kee tac es hare ges HO A as -001 -001 .001 aC Hrsg he eee ey pee Uy Screen no eae 2.00 2.00 2.00 1284. Hydrometers, Specific Gravity, for liquids heavier than water. Approximate total length 9 inches, length of graduated scale 3 inches. Takes a cylinder 250 x 40 mm, and require 175 ml of liquid for sub- mersion. As used in Barrett Tests B-4 and H-3; also A. S. T. M. D-38-18. SCA e tie Eicon ee IORI Melee ERR ANS fu DN ope y ee tues te nes Cae ore 1.000-1.080 1.070-1.150 Graduated CO isco Sach os AS eet eR rae te Sega ele oun, Ayala cad .001 001 BACH sens cece arty eee ce teers ey anak ey ienach B a akc a aa es 2.00 2.00 1286. Hydrometers, Specific Gravity, for liquids heavier than water. Approximate total length 9 inches, length of graduated scale 3 inches. Take a cylinder 250 x 40 mm, and require 175 ml of liquid for sub- mersion. As used in Barrett Test B-4. Sal Gin ceced iy toc Oey th vrata tees start en haben Waaaak Mata Nee dea were te toe OLN 1.150-1.230 1.230-1.280 Graduatedto........ Seek deere here caries | areca tact Mae ree te tyra en ian A -001 .001 ESCM ec ai sods toy ah eng ee TRCN RD SE RU SRR GA Peele SS Ais PON ena 2.00 2.00 7232. Lactometer, New York Board of Health Form, with Spence scale, in which specific gravity 1.029=100. Approximate total length 12 inches, length of graduated scale 43 inches. Takes a cylinder 300 x 40 mm, and requires 225 ml of liquid for submersion. Without thermometer................. 1.70 7233. ditto sbutwithithermometer. 12 cm <—_ 6250 6259. Jars, Rectangular Museum, with flat ground-on lids for permanent sealing. These jars are of clear white glass of extra fine finish because of being blown in wet wooden moulds. The annealing is more nearly perfect than in any similar jar of our experience, which feature reduces the breakage in storage and in museums due to sudden temperature change. The lid of each jar is furnished with a small hole for vent. The sizes offered are those recommended by competent authorities, and include sixteen sizes as used in the U.S. Army Medical Museum. SIZENUMDET a3. 24.08 fo ka alee wee 1 2 3 3a 4 5 6 7 Ta Heightem 22) 2 sae Mae eines Ae gees 5 10 15 15 15 16 20 20 20 Width, em. . Soe a near 5 4.5 8 10.5 15 10 8 18 15 Depthetenis xe ci paitiinent aun c 3 3 5 5 9 8 4.5 8 10 Bach. aye Sten acy cater Obie Ae 54 62 96 1.08 2.00 1.30 1.20 1.85 2.64 10% discount in case containing... . 150 75 60 50 40 45 35 30 25 Size number’..5 » 262225664 seek ease 8 9 10 11 12 13 13a 14° 14a Height emi eager Se 20 22 25 25 22.5 25 26 30 30 Width,em......... patdtad Vien tent a 13 15 22 25. 17.5 25 15 20 25 Depth, em. EGU oe wins as a 13 5.5 10 12 9 14 8 17.5 6 ONG 5 5 oe Seok Scns tee nactanioh oer qaomn ts eu 2.25 1.90 3.45 4.00 3.00 4.85 2.68 7.35 4.68 10% discount in case containing... . 20 30 15 10 25 10 10 8 10 Size number... ............000..- 14, «15016 sdT—si—iaKs—iaY Dstt Height. em sis is jeune ean wx: 31 34 36 42 50 40 30 65 40 Widthscems see each homer Sai ks 29 25 15 10.5 25 30 50 30 40 Depth, cm. . bedsores ee 11 12 10) 7.5 12 25 15 20 25 ACH sieetsen ae cn eae Seen aaa 6.56 8.25 3.45 3.24 14.40 18.80 24.00 32.80 25.20 10% discount in case containing. ... 8 6 8 6 Note—On special order, at an extra price, these rectangular jars are supplied with one side highly polished instead of mould finish, but jars with polished side are not carried in stock. Glass Rod, Colored, of suitable dimensions and colors for the mounting of anatomical specimens in museum jars. The designations of the colors are those used in the technical factory control and as they do not always convey an accurate idea as to appearance we explain them as follows: Amber—Semi-transparent, very light brown Blue—Black, i. e. the blue is so dense as to give the effect of black Copper Ruby—Opaque dark red Gold Ruby—Semi-transparent, dark wine color Opal—Opaque white Turquoise—Opaque light blue The rod is carried in stock only in two dimensions and is furnished in factory lengths of 8 ft. only. 6094. Glass Rod, Colored, as above described, ;;-inch diameter. COlOR SS i et Abas cata Ben Shee cae then Amber Blue Copper Ruby Gold Ruby Opal Turquoise Per 3=ft» length s...c65.6506 fcc he evan 2 .25 -25 -60 1.50 25 25 6096. ditto, but }-inch diameter. Per: 3-ft-length 00.6 hanes 4 OR oe. 45 45 1.00 2.50 45 A5 6252. Jars, American Medical Museum. A rectangular jar of patent construction which provides for supporting specimens on glass supports Nos. 6253 and 625!. The smaller jars have one pair of depressions, while the larger jars have three. Each lid has a small hole in one corner through which the fluid contents of the jar may be changed, or additional fluid added after sealing the jar. The assortment of eleven sizes are those recommended by competent authorities. Complete jar and cover, but without specimen support. SIZESMUIN DOR asset Feed oes arta eet ck eae eee 1 2 3 4 5 6 Height, cm. i - 5 10 15 15 16 20 Width, cm... Be 5 4.5 8 15 10 8 Depth, cm........ 28 ae 3 3 5 9 8 4.5 Hachiseirs Aaa owe, : anes 55 70 1.35 2.50 2.10 2.50 10% discount in case containing. . Sk er 240 180 48 24 36 30 Sizeonumiber nets te Sans a haces Oe oe he yes 7 8 9 10 11 Height, cm.. ; : se! 20 20 22 25 25 Width, cm.... wae - se 13 13 15 22 25 Depth, Cm .i cee kena ne 28 13 5.5 10 _12 aC hihi ern natn tae tures .. 2.70 3.40 3.50 8.00 13.00 10% discount in case containing. Od ede GES AIA rane 18 18 18 12 9 —————______ 6253. Specimen Support, to fit American Medical Museum Jars, consisting of a straight eee glass rod of sizes to fit the respective jars. Size number .. . 1 o 3 4 5 6 7 8 9 10 11 Each...... 10° 210) 10° 2) 10: 310° 12, A? 2 ASS Per dozen..... 1.00 1.00 1.00 1.25 1.00 1.00 1.25 1.25 1.25 1.50 1.50 6254. Specimen Frame Support, consisting of a glass frame with projections to fit in depressions in top of jars; for specimens which require stretching on the frame or support at both sides and top. For jars number 1 2 3. °4«4 5 6 i 8 9 10 11 Each.......... 25«(25)~CO2t«s«i«ist«i«iSC‘ “’SOC«#SSC«ASC«i«‘SC«C*OO Per dozen..... 2.50 2.50 2.50 3.00 3.00 3.60 3.60 3.60 4.25 4.25 4.25 353 AOR Hs UR H. T H O M A S CG. - OMe Pa A Ns GROUND SURFACE. ih TT A a Tin 359.5 35x* 30cm cn 6256. Jars, Museum, Hopkins-Columbia Model; with flat lid with airtight grinding” between lid and top of jar, as shown in diagram. The portion of the lid or stopper projecting inside of the jar is unground and fits loosely. This arrangement provides a flat lid for convenient stacking, and which is not easily removed; with a ground surface for temporary or permanent sealing which obviates all pos- sibility of sticking, a difficulty commonly experienced with all large jars with ground-in stopper. Height, CMs. oc aiswexdoasd cones 12 15 18 22 22 24 30 35 85 Diameter,em.............. 6 8 14 10 20 14.5 15 9.5 30 Walia n ey cer Siete 72 114 2.70 1.95 5.40 3.25 4.00 3.00 20.70 10% discount in case containing 100 50 32 35 6 10 8 20 4 2 «10% 104 x 884 6258 6258. Jars, Storage, with slight constriction at neck, also provided with a rubber washer which renders the jar partially but not entirely airtight. These jars are remarkably low priced when the size is considered, and have been found very convenient for laboratory use. Meight,inehes =). 2 nso ied) i .cteneeaNo atnaee tascn Saas 2 as 10} 114 123 133 Diameter, ANCHES: 5 4.5 psicice Saeed deed cbthe nse eat y i 3 10} 10} 113 Capacity gallons cc scmvuldactiat wnledw exeluesevaameh nee a 1 2 3 4 5 Balchin i oh rs ce ie ks Se Oe en eee ee hc 2.35 | 4.75 \ 5.00 6.50 8.15 10% discount in case containing.................. 10 4 3 2 2 6259. Rubber Gaskets, only, for Jars No. 6258. Each.......... 10 10 10 10 10 354 6260. 6262. 6263. 6264. 6265. Jars, Storage, with lid smoothly fitting but not ground airtight. jars may be readily stacked one on top of the other. in laboratory work for the temporary storage of specimens. Knob in lid is countersunk so that These jars have been found very convenient Height, inches................ Pee ee ek 33 43 58 6 64 Tt Diameter, inches yt re 61 61 83 93 102 113 Capacity.......... 1 qt. 3 pt. 6 pt. 9 pt. 18 pt. 2 gal. Each. ga tanetire athremvedteney eta .80 1.00 1.80 1.90 3.75 4.40 10% discount in case containing.......... 36 28 12 10 7 5 Jars, Standard Museum, with mouth same size as body. glass suspension rings on under side of glass cover. 18x7%| ne Se Be arco With rubber band and metal clamp and two For over 20 years this has been the standard American cylindrical jar for museum purposes, particularly where preserved material must be easy of access, i. ¢., not in a permanently sealed jar. Height; inchese. 2, ouuiked sea kegeas esa ies 4 8 6 8 12 18 Diameter, inches...............-0. 00050055 1 2h 34 32 32 1 Capacity, pints: o..cc0. eee sewe kee eens : i 1 13 24 4 6 Each...... Bh scansfe ies Gis ee ae REM evar MG astetay 95 1.05 1.40 1.50 1.75 2.10 Per dozen... Pidtok ater cde Rade Mie ee tse 9.50 10.50 14.00 15.00 17.50 20.80 Height, inches............--.--....0-05: 8 12 18 8 12 8 Diameter, inches................. 6 5 5 63 61 78 Capacityiec ins che an ct ee eee ee ae 23 qts. 4qts. 6 qts. lgal. ligal. 13 gal. Each ... poke sats 2.65 3.15 3.65 3.40 3.80 5.25 Per dozen....... or 26.65 31.50 36.50 34.15 38.00 52.50 Height, inches... . 12 18 24 36 12 18 24 Diameter, inches............... 73 73 78 78 113 113 113 Capacity......... 2: gal. 3igal. 4i gal. Tegal. 4% gal. 7} gal. 10 gal. Wahi nbk cee oe en Bee aS : 6.00 7.00 8.00 10.50 12.40 15.75 19.70 Per dozen.............-0.00055 59.85 70.00 81.00 105.00 124.80 157.70 197.00 Fittings for No. 6262 Jars. Diameter, inches. ... 1 i 5 64 18 113 Lids, only, each. . 0.6... ee .07 15 .26 37 .65 1.70 Clamps, only, each...........-5--. 00005. e aes .33 -40 -62 .73 1.16 2.25 Rubbers, only, each..........------2:5 020s .03 1 .25 .30 48 1.10 A: oR FT -Ae UR Fi T H O M AS C—O" Ms oP A NY 1ox3% | 6266 6266. Jars, Standard Specimen, with extra wide mouth and stopper carefully ground in. For many years the Standard American specimen jar Height, inches.............. 3 24 34 5 34 5 7 4 6 Diameter, inches. : 13 2 2 2 23 23 24 3 3 Capacity, ounces... 3 3 5 6 8 11 16 14 20 ach icc es wile i < nieve DO tb oI 34 36 389 .45 46 51 57 60 .68 Per dOZENS votes 3. 3.40 3.60 3.85 4.45 4.56 5.13 5.70 6.00 6.84 Height, inches.................... 6 8 10 5 8 12 7 10 Diameter, inches 33 32 33 42 1 1 6 1 6 Capacity, ounces 299 40 52 38 62 92 98 140 Bachiss cc aia eeeied eco ih oes eeaas : 90 1.08 1.28 1.11 1.37 1.65 1.95 2.56 invoarevatdhen Wied. Mee BONES . 8.90 10.80 12.80 11.10 13.70 16.50 19.40 25.60 6268 6269 6270 6268. Jar, Museum, with foot and ground-in airtight stopper with knob. Lid is provided with downward projection 1 inch deep which is ground, as is also the inside of the jar for the same distance. Inside dimensions, 73 inches high by 43 inches diameter........... 5.00... cece eee eee eee 2.40 6269. Jar, Museum, with foot and ground-on lid with projection 3 inch deep inside to keep lid from slipping off. Inside dimensions, 72 inches high by 43 inches diameter 1.80 6270. Jars, with lid closely fitting on shoulder but not ground airtight, with cut and polished knob. So-called “Dressing Jars.”’ Height: Anchess 2 sgkc wishes Aueme fiche hoiy seneet Smet atic glans ARG So A a ae ete 4 6 Diameter, inches........... gre A ee P Cae ak po ee : 4 6 6272 6274 6272. Jars, Inverted Specimen, for cork stopper. Height; anChess..).g4 vesicle o2 Qaad 33 4¢ 6 73 9 11 14 Diameter, inches............... 13 2 2 23 38 4h 53 Ga pacitys cues tng hes Brennen et $ pt. } pt. 3 pt. 1 pt. lqt. gal. 1 gal. Pte a Fee sie eek ses wot 31 38 51 -68 1.02 2.05 Per d0ZeM 3 ce55 2k Fa eee es 2.70 3.05 3.85 5.10 6.80 10.20 20.50 6274. Jars, Preserving, of green glass, made fairly airtight by means of a spring wire clamp and rubber gasket. A very low priced jar for temporary storage of laboratory material. Gapacity io Sisk mek reise a a where ee arom eaweoegs cay hein eyein cm meaieei ren: 3 pt. 1 pt. 1 qt. Pa CHS cle oe og cre ace toes stk ale cates Rcceyel els eaal manele et galavacemn eA Bigs 12 14 18 10°% discount in cases containing 144. SION LEN [AKT co | 6283 6278. Jars, Preserving. Offered as the most satisfactory household jar for laboratory use. The necks are without constriction and threaded on the outside, permitting the metallic clamp to hold the lid absolutely airtight against the rubber gasket, and to be tightened and loosened at will. The me- tallic clamps are non-corrosive in any climate. The glass, while not entirely colorless, having a slight greenish tint, is much less green than the ordinary household jar. Gapacity; Ounces ies heck Wise ee cis Sa ashe aun Allan Sadat Mar ti rel A ate fae A 8 18 28 aC Ue secrete nc ge me Ne ae Me nai nay rere PTAs Meat At 18 20 .23 10% discount in cartons of 1 dozen. 20% discount in cases of 1 gross. a 6279. Metallic Clamps, only, for above Jars. Per dozen..................0 0000 ccc ee 40 6280. Rubber Gaskets, only, for above Jars. Per dozen................. 0000 ee .25 6283. Jars, Jam, with lid held reasonably airtight by means of a spring wire clamp and rubber gasket. A very widely used jar for temporary storage of material in laboratories of normal pathology and histology. 4 3 4 6 43 Mei ght INCHES sc ve Gora 6 tess av eva wee Accom ees aba 14 3 ‘ 2 Diameter, inches) 24 esses eh os ed ed 14 2k 24 3 3 4 Capacity, Ounese = i..2 asc bas eae dae ck wed 1 5 8 10 16 24 Each 3 Bie ies Ae neue dendtns Sameaun oeseeenena 14 .20 -22 25 30 -50 10% discount in cases containing 144. \ 6284 6284. Jars, Screw Cap, with cork-lined metallic screw cap, making a fairly airtight joint. Height; inches.c.. Raxccoc i hatG av ediage Shee Gere he 3h 33 43 4i2 53 Diameter, inches...........--- 00-000 eevee eee 1k 1k 1: 22 3h Capacity, ounces)... 6.6: sca2e- are ta ney eee een 1 2 4 8 16 Peer oZens snes once eg a re a 1.00 1.10 1.35 1.80 2.70 10% discount in cases containing 144. 6285. Jars, Screw Cap, square, with cork-lined metallic screw cap, making a fairly airtight joint. 3 2 Height, inches... 005.6000: 0b be cee pe ee eee wee ee ee eee cats 23 33 4} Widths Gnches.ccseeagiannysnr ni toekiaionls Woe tuscan se eb ee aye: 1i 13 13 Capacity, ounces... 6.62. Rapa 1 2 4 PP rsd Ze ies 6 econ sehen ea Ieee ea eS DRAG Toran cee hd te 1.00 1.10 1.35 10% discount in cases containing 144. - , Ointment, of glass, with metallic screw cap lined with paraffine paper. The bottoms are slightly ate ae eaaided tide and the inner surface of the jar is straight and smooth, 7. e. without shoulder. Height, inches.........0.6 00000 e cece eee eee eens 1k 2 24 Diameter, inches... .........-.-: EUAN sORT GI aera ete aht geil gona terse Nee : 2 24 28 Capacity, ounces..... ie Teco eae thread oo eeslaie Rese haathy Aarne et aN AT aN lee ene eee Gr COZENS Be net EF GI Ee a Dee 1.45 2.15 2.60 10% discount in cases containing 144. . Jars, Glycerine, with metallic screw cap lined with paraffine paper. The bottoms are slightly rounded ica sc acide and the inside of the jar is straight and smooth, i. e., without shoulder. 7 Height, inches........... 0000200 eee etree eet t ete 2 25 34 Diameter, inches..........--.+-5+-+5 aie eens ache tne tee arn geen a8 lt 1 13 Capacity, ounces...........-..5-5-- Sn Ate ems mene og Ahsan Phe pe eg een ee Pere dozerticg ok eos cease) ee gg ate en ean 1.20 1.40 1.70 10% discount in cases containing 144. hi y 7 6290 6291 629 6290. Jars, Precipitating, straight cylindrical form, with spout. Capacity, ml... ... 125 250 500 1000 2000 4000 6000 10000 Each . eA oO 45 -60 1.00 1.50 2.50 3.50 5.00 6291. Jars, Presse conical or Sapenne form, with spout. GaPa city. a sme, oecuals ucbarte as ... 8o0z. 1602. 382 oz. zeae lgal. 2gal. 3 gal. Height, inches......... 3 53 6 8 7 12} 15 16 Top diameter, inches. : : 1: 23 3 x 3 41 6 7 Bachizcs23 238. Pune 2 a .85 -90 1.55 2.00 2.50 5.00 10.00 6292. Jars, Waste, of glazed stoneware, with two handles and cover. Because of their low value in relation to their bulk a considerable part of the price aes is for the necessary boxing. Capacity, gallons. PA AAR ora Ee 4 5 6 8 12 Total height, inches... : 14 16 LY. 184 20 22 Diameter, inches......... ee 10 12 13 13 143 16 Bachice ora cater sis ‘ chee. : 1.20 2.20 2.80 3.20 4.85 6.25 6293. ditto, but without cover. Capacity, gallons......... as cuias. tok 2 4 5 6 8 12 Bach). cic vce ie ua ces Ue eer 1.00 1.95 2.55 2.90 4,45 5.75 6294. Covers, only, for above. oe : a é .20 25 25 .30 -40 -50 6298. Knife, Laboratory, with 33-inch 1 leds of caeane shape for cutting corks, and for other laboratory pur- DOSCSarynis cr tn hehe the ered pea tey Pine a eae eee tt te Sad tO tac le Re agi mites Roses her A -20 6066. Knife, Glass Cutter. A most convenient and eae laboratory utensil...................... .80 eR te — ase % ee eS , ; | 13716 x1 Se ih | Mex Ae ) ee xe | | | | 6300—(Actual size) 6301 6300. Labels, Dennison, pummens on white paper with red border. pe : Pee S Bat neni ok 225 223 217 213 209 205 201 izes, incl exten ; Panes ax eXte lgxtt 134x1l 1x1} 3x13 23x14 Number in box. aes ae Pe We ea Per box... ‘ 10 -10 10 -10 -10 -10 10 Per carton of 1 doz. boxes... _. ... 1.00 1.00 1.00 1.00 1.00 1.00 1.00 6301. Labels, Dennison, gummed, perforated, in rolls. Each roll is contained in a special box with slot opening so that labels can be drawn out as needed without opening the box. Each roll contains 1000 labels. Number... BA eats chen) on aa tee gona Rea Peed che ne A eri 217 209 205 Size, inches.............. pig eas es e ooo... 13x18 1,5x14 133x145 PerrOllecay ee eon Wer g ih west: Gets enone: nitevta eee nL eee 0 Per carton of 10 rolls. : es Me aR actrees eur co a 3:00 A R T H U_R H. T AH © M AS c Oo M P A N Y | 8313416 x 1946 Ss Ato, oF 6303— (Actual size) ATCO 6302—(Actual size) 45g X 2 : 1 | 46x 1% 2728 X 15¢@ is is 6307—(Actual size) 6308—(Actual size) 6302— (Actual size) ARTHUR H.THOMAS CO° WHOLESALE RETAIL AND EXPORT MERCHANTS pete aS Fn aan LABRATORY APPARATUS AND REAGENTS iY a | WEST WASHINGTON SQUARE a PHILADELPHIA Ae USA. | 1 | 12% % \ / / a / [TED ew see ees ae 6304— (Actual size) 6305—(Actual size) 6309 6302. Labels, Dennison, gummed, white with red border, large rectangular shape. Packed 75 in a box. INGimmberse seat i daneiahe etad eee 2004 2007 2001 2005 2003 Sizes in Chest2G an laron ses thant oouatuh BR certo te 23x12 3x1} 38iixlgs 4y6x13 43x2 PT OK Sse ay eae einer op eeaes av .20 -20 .25 .30 .35 Per carton of 10 boxes.............-.-.-00-000555 1.50 1.90 2.30 2.65 3.40 6303. Labels, Dennison, Oval Shape, gummed, white with red border. Number....... Shad Shee PMG Me Nice eb yee pat ve Sk ty San er on oat en 241 239 229 Size, inches.......... Ci ct era alae a AHA A eek Ute ar ORS ears RR AE 28x25 1fgexte lixlis Per (boXxXscon5 23 ass oe rae Pett Ge AG eRe Ree cee eer et -10 10 10 Per carton of 12 boxes... 2.0... eens - .90 -90 -90 6304. Labels, Dennison, Circular, gummed, on plain white paper without border. Each box contains 1000 labels. Number....... red ene ERR Racer eter Rent aro rh Ree em hs ieteeny tent aay ee aaa ke A 83 A 85 Diameters inchess cscs ios es Saas ak hiearsee eed OG he a ee DE ESS 3 a PSE Dio Kes alc cee ets tence 8 Gag) IC Oe Pa G Betts ea Reka eee .25 .30 Per carton of 10 boxes. . 0.6. ee re EEE EA ee ees .. 2.50 2.75 6305. Labels, Dennison No. A-18, gummed, on plain white paper without border. Rectangular, size 1)x} Per box of 1000 labels..............--..5- 40 Per carton of 10 boxes...............-. 3.75 6307. Labels, Micro Slide, gummed, 22 mm square, with blue border. Per box of 100 labels.............. 12 Per carton of 10 boxes... ........0 0-0 e ees Sh Yee ev aisle Sh Skee hn ahr 1.00 6308. Labels, Micro Slide, gummed, rectangular, 22x15 mm, with blue border. Per box of 100 labels..... 10 Per carton of 10 boxes... : cs c00 pee cee eee nhs ne PREP EEE ER rn tiny Stk gt .60 6309. Labels, Micro Slide, in books of 500 labels each. These labels are printed on best white gummed paper with blue border; size 22 mm square, and are scored so as to be readily torn from the book, leaving clean edges; interleaved with paraffine paper. Per DOOK ns ked fa eR ele en ea ee aes .40 359 POTASS, CHROMIUM SULPHATE | 1A 6312, 6318, 6314 CHROME ALUM. K2Crz(S04)4 + 24H,0 6310. 6312. 6313. 6314. 6316. 6318. 6319. 6320. 6321. 6324. 6326. 6328. 6329. 6310 cL 6319 Labels, Chemical. A book of gummed, perforated labels, each bearing both name and symbol of the ordinary reagents, and arranged for convenient removal without disturbing the book. Per book containing 500 labels\c.3 voec Ste oe we a eh ee ee ila ee A etn eee cule ede 50 6326 Labels, Figures, 0 to 9, of blacked gummed paper, exact size of illustration. Very convenient for labora- tory labeling. Per box containing 100 of one figure.................00 000.000.0000. e eee -20 Labels, Letters, A to Z, of black gummed paper, exact size of illustration. Per box containing 100 of ONE Tete Nr aio. nes pean he ie teeth wenn ieee Bala wl a hipaa al fan wom he Wen nae leak oe yan LAN itu tat Me aa -20 Labels, Letters, of black gummed paper exactly same as No. 6313. ‘‘Handy Box’’ containing 1000 letters, assorted, put up to give a large number of letters most used, and few of such as Q, X, etes, whichsare Sl d OMsMSEG ends och aos tae ee eases aah tas weber cette donieehe ope oad ott Meade arene 2.50 NoteE—The figures and letters listed above make durable and satisfactory reagent bottle labels when neatly attached and covered with a coat of shellac. Ladle, of wrought iron, with lip, 4 inches diameter................00.0 000000 eee 590 Lamps, Alcohol, of polished brass, with metal cap. Capacity; Oun CES 9 Sc6 cation nent yeascattee Nee an. Rae WN a alley Renta hd Su ere cate 4 8 VON ee cn oa sete a eae a pss aes mTOR ee ers MICH Leet ae ERS eC a ties E .80 1.10 Lamp, Alcohol, College Type, with screw cap, nickel plated, size 23 inches diameter by 2 renee high... 1.60 Lamps, Alcohol, cylindrical shape, of glass with cap ground on. With metal fitting and wick. Capacity, MMe pany tel ee eens Na rae ite ns ca tata chee ce came tak Eni ott beer aah 30 60 100 IACI og se ote ites ta ae oat ete ake eho Ghent Sam, on BOs FINO Beas ht el 30 40 45 Lamp Wicking, a wick of any size is obtained by using the required number of strands. Per bundle :of 12 fits. 2. 1a icsteigie Seo ee He ea nay reel Na a A een ate lt 15 Lead Shot, No. 6, for cleaning bottles. Perlb... 2.0.0.0... 000.0000 teen . 12 Lens Paper, Japanese, for cleaning lenses. Does not easily collect dust, or become greasy and harsh. It is very soft and free from impurities. Size of sheets, 7+ by 11 inches. Per package OLOLOO SHE CES i eae ok rat nese Bes eon gaa te oh ae ee UIE a nt te tel Dea eee Sle 40 10% discount in lots of 50 packages. Level, round, in brass case, nickel plated; 15 mm diameter...............0.0 00.0.0 e cence ee 15 Magnets, Bar, of steel, best quality. Length,mm.................. Atay, eee eashat 150 200 CHa ee ee ane eet ns NE tet eet ahi thea eee enon aaler as Ura eee .30 40 Magnets, Horseshoe, with armature. Length,mm............................ cedar 100 150 Bia chic stone act shore tre eka peek textes eta cess arnt rr ees A eA ome ts tye cade SE 25 -90 Metric quantity specifications for items listed and packed on the dozen basis, and vice versa, result in unavoidable delay in shipment and tend to retard, rather than advance, the universal adoption of the metric system in commerce and trade. We favor the use of the metric system wherever practic- able, but encounter many difficulties in the way of its rapid adoption because of the use of automatic machines for the making of standard cartons and boxes, and long established practice in trades other than those connected with the Laboratory Apparatus business and finally, because of many items which pack better by dozens than by tens. For example, certain articles pack in a carton of satisfac- tory shape in three rows of four, rather than in one row of ten or two rows of five pieces. 360 6332. 6333. 6334. 6335. 6336. 6337. 6338. 6339. Magnifiers, Pocket, Oval Shape, Single Lens. Mounted in best quality vulcanized rubber; durable, light weight and of neat appearance. INUIT DO sco ee ck Sor ct tay Sh ema UG Geer tartan ha rsuaratenn eee © 56 62 68 Diameter of lens, mm.......... : ee 25 30 37 Magnification... . es Naan : : i 4x 3.5x 3x Ce ye ee ee oe PET ARS Re RES a aE gato TENE Renee: 1.35 1.75 2.25 ditto, but double lens. Number.cs-icecscen anaes Pee eS a Seana eee toed eee ect) ge EAH 57 63 69 Diameters of lenses, mm. . ; ... 21,25 28,30 30,37 Magnification.......... 5 Megs eee .... 4to 9x 3.5to8x 3 to 6x Beha ee as tS SGA EE eS iter NS edt 2.50 3.35 4.25 Magnifier, Pocket, Bellows Shape, Triple Lens, No. 103. Mounted in best quality vulcanized rubber, durable, light weight and of neat appearance. Diameters of lenses, 12, 15 and 18mm; magnification EOP SOK see ao Pianeta ec neh ete NDE ne loa) ete sale ur @ aac wetse Ga aaa Shane oe areas Unread nse 3.00 Magnifiers, Doublet. Consist of two separate plano-convex lenses; mounted for use on dissecting microscopes. Number............ Cadet Asem A ARC e HEM oxo ed rea E a Ratna Tn nn ko anomie 1 2 3 Magnification......... A aaah he oae ee atti er oe ene 7x 10x 14x Equivalent Focus,mm.......... We eathiee eases ae eee ear aoe 38 25 19 Diameter of field, mm... Baa Nat onan a aviator PN cee ees 18 16 10 Working distance, mm.............----- Nh Vek aa ctatiets Mtn A amnesia sare’ 20.3 20.1 8.9 Pee Bek ee reelected ie am eb aicaye are ng eae eR Val 1.75 1.75 1.75 Magnifier, Doublet, No. 6, magnification 14x, equivalent focus 19 mm, diameter of field 10 mm, working distance 8.9 mm; in metal hand magnifier mounting with hexagonal handle................ 1.75 Magnifiers, Doublet. Consist of two separate plano-convex lenses; mounted in metal folding pocket case. NH DOD so oars aed eo au gcd ese BESO EE SE OE eae thes Ses Mi Ta Magnification.............---- Bea Upc oneman pane eh erent es eee sein & adhe 14x 12x Equivalent Focus,mm........ Baap her PONS ences create wake Ree ant Rat as Rome fen ta 19 22 Diameter of field, mm............. 0005000 e eres My Enea MyGen: 10 12.5 Working distance, mm............- eS Bn ects ee te time oan erin nba kate age 8.9 12.5 2.00 2.00 Magnifiers, Coddington. Give a good definition and a wide field. Composed of a cylinder of glass with a deep groove cut in at equal distance from ends to serve as a diaphragm; ends of cylinder ground spherically and polished to form lens surfaces. Mounted in metal folding case. 163 162 161 160 Number woo, ein ees tome een nes a ne enema eH Magnification.......... Koi gets Fai ae eee ee TX 10K 14K 20X 38 25 19 13 Equivalent Focus,mm......... eee Serer: Diameter of field, mm............ i z 3 30 20 14 8 Working distance, mm........... 28 18.8 14.1 8.4 3.25 3.25 3.25 3.25 Bah se ng psn ae ee ditto, but mounted for use on dissecting microscopes. : Naber Sha hiran Ahi Gls Sones aA btlcye fea e du atten Re teea Gene ettnieee nada Suartaarineeg 163a 162a léla 160a Magification...... Fe Ais acted tery chat eay abiea Coon bear cist ; TX 10X 14x 20X BEACH chen pase BE rete eA eh ee ies eee Be 3.00 3.00 3.00 3.00 6340. 6341. 6342. 6343. 6344. 6345. 6346. 6347. 6348. 6349. Pik | a) se 6340 Magnifiers, Triple Aplanats. A high grade magnifier with a large field and perfect correction for chromatic aberration as well as flatness, astigmatism and distortion; new construction designed for highest grade work. Composed of two meniscus lenses of flint glass separated by double convex lens of crown glass. Mounted in metal folding case. 6344 INGUIMID ER fake ie Sicha sistas, sete a3tho Gabe, Seren cart un aM Neuman rar dat onr tare 168 167 166 165 MES on CAtlOME rs wins eae sources eens la clagclg thew aoa we Nene an Aas BOTAN 7.5X 10X 15X 20X Hi Gurvialenit. HOCUS, Sin .8 erence tnt ck seers cath J iaph Suatraclatenasesa wit a eR 34 25 17 13 Diameter of teldy mim j.2. 2a: Se cyan Sean eRe esige Re eereet 28 20 14 8 Working distance mim. ws.az + teases eminem ee eee 29.5 22 15 11 BACH aches fee ees cates Ceres ght hie abet aah cae cae ohare rege to 6.50 6.50 6.50 6.50 ditto, but mounted for use on dissecting microscopes. INT De tase taints oe Naat: Octet Care OAR AEN Ae. FUR cre ran a 168a 167a 166a 165a Magnification . 2 aan Dalal yobs Lace A ean plead Mh agg Pram ee neta es as EDX 10X 15X 20X ACM es aes ss mea i ea aes a eet ne ren meee iy Ss 6.25 6.25 6.25 6.25 Magnifiers, Hastings Aplanatic Triplet. With a very large angle of view and corrections of a high order. Mounted in metal folding pocket case. INIT Or te ered aed ah sence epee Gun A ail Pea sae om pea es Riese dae 173 172 171 170 Maonitication': IMs PRP GAS cNeo 6575. Combined Grinding and Polishing Machine, Wysor, triple spindle type, similar to the single spindle machine excepting that three spindle heads are provided, i. e., one for each of the three polishing dises, thus avoiding any interchange of polishing discs. For round belt drive, without THOCOPM sae-uutcent is ever netnhe oat atl bythe aay nA apne eed tang Pie ance Aue wis Mleantd Rig Ciah Mire apaegen cies 120.00 Norr—The three spindle Wysor machine is not regularly furnished on a base with motor. A !4-h.p. motor is required, which gives a speed of about 800 r.p.m., with a 2-inch pulley. 6576. Grinding Wheel, coarse, 6 inches diameter, ?-inch thick, with }-inch hole.......... : : 3.25 6577. ditto, medium, 6 inches diameter, inch ‘thick, with 34-inch hole. ces 3 Pte wecDO 6578. ditto, fine, 6 inches diameter, 3-inch thick, with ETCH Ole eer aston tae ne een eR ees 2.50 6579. Grinding Wheel, of Alundum, coarse, elastic wheel for roughing, grade 46-4, 6 inches diameter, {-inch Chicks -withs=inChe Ole ssc atytachash s eehisrcchiseh cad myo aie nou ao tse ais ao Pa nsonoee a tans Reheat 9 eaters 2.10 6580. Grinding Wheel, of Crystolon, medium, for removing feed lines, grade F-N, 6 inches diameter, 3-inch VOR WGI ETI OL Os ore ree rae Mrcnedgesean tae ne oR ai Sie Mig shave secs teem sel prembhid 2 abe Seascedtue saoet Se apt edpem at Bo 1.80 6581. ditto, fine, for semi-polishing, grade XF-M, 6 inches diameter, ?-inch thick, with 2-inch hole... 1.80 6582; Polishing: Dise; of brass, without:clothsi.....: 005.00. ccacW as asec eee pins eRe tek Ghana beta gas 4.50 6583. Cloths: (Periset 0ti5s cian a. eS cee ee KS Dehetre NTC iss eee Ee ene hanes -50 6584. Emulsion Bulb, of glass, with rubber stopper................ Sheedy : ‘ AT bet ee tae 55 6585. Wooden Stand, for 4 emulsion bulbs............0...0...00 000002 e eee eee a ark 1.50 6586 ROUGH GRINDING MACHINE FOR METALLOGRAPHIC SPECIMENS. This machine is intended for rough grinding in straight parallel lines. The specimen is turned at right angles when changing from the coarser to the finer grinding. This method permits the observation of the rougher scratches of the coarser grinding until they are completely obliterated by the finer scratches at right angles to them. The specimen is held against the flat steel top of the machine and against an attachment which holds the specimen firmly while being ground, thus insuring an evenly ground surface. The carborundum grinding belt runs over this flat steel top at a speed of about 1000 r.p.m. A }+h.p. motor with 23-inch pulley is required for operation at this speed. The grinding belts are 4 inches wide, and the dimensions of the flat top of the machine 10 inches long by 6 inches wide. The grinding belt is tightened by the suspended metal cylinder, and the machine is equipped with tight and loose pulley, belt shifter and a vertical disc wheel attachment, 8 inches diameter, for use in roughing out work. This is not shown in above illustration, but is attached by a set screw to the center shaft at the right which ex- tends about 14 inches. The grinding belts are conveniently and rapidly interchangeable and this machine is suit- able for rough grinding of very large specimens, such as sections of rails, shafts, etc. 6586. Rough Grinding Machine for Metallographic Specimens, as above described, with three grinding belts of carborundum of different grades of fineness, but without motor......................- 55.00 6587. Carborundum eine Belts, only, for apeNe machine. Grade. . Seas a ence eg ene Very Coarse Coarse Medium Fine Very Fine Bat Cterscce a oa tte crate creer oan en ate .50 -50 -50 50 50 378 F, Upper focal plane of objective. Virtual image formed at the F. Lower focal plane of eyepiece. projective distance C, 250 A. Optical tube length =distance mm from between F, and F,. Eyepoint. O, Object. Condenser diaphragm. O, Real image in F., transposed Mechanical tube length (160 by collective lens, to mm). O; Real image in eyepiece dia- ,3 Three pencils of paralle phragm. light coming from different points of a distant illuminant, for instance, a white cloud, which illuminate three differ- ent points of the object. Diagram Showing Path of Light Rays. The essential features of Bausch & Lomb Microscopes necessary to an intelligent selection and comparison with other makes are as follows:— Focusing Adjustments. The coarse adjustment is by rack and pinion with diagonally cut teeth and provision for adjusting pinions after long service. Lever-fine adjustments have now almost entirely replaced the prism form of fine adjustment. The lever- fine adjustment is an application of one of the oldest and most durable forms of fine adjustment applied to modern stands. The construction is shown in Fig. 1 on following page. When the fine adjustment screw head is rotated, its movement is imparted to the lever, which in turn imparts the motion to the body tube. By means of a left-handed thread the clock-wise movement of head imparts a downward motion to the tube. The adjustment ceases to act the moment the objective touches the specimen. This prevents injury of ordinary specimens and objectives, as only a light spring is required. The micrometer screw has threads of 0.5 mm pitch, and with lever arm of unequal length, that is, the lever arm twice as long on the side toward the screw as on the other side, one revolution of the screw-head moves the body tube 0.25 mm. When the fine adjustment head is graduated into one hundred parts, as in the FFS, each division represents a movement of 0.0025 mm =2.5 microns. The large broad bearings are placed very near the optical axis, and the screw is called upon to carry only the body tube and rack adjustment, no matter how great the distance from the arm to the optical axis. All parts of the mechanism are encased in the arm, thereby protecting them from dust and injury. The micrometer screw head is locked so that it cannot be removed without the use of special tools. A later adaptation of the lever-fine adjustment is the side wheel form shown in Fig. 2 on following page. The screw, which may be rotated by milled heads on both right and left sides, is standard 0.5 mm pitch, with a thread of such form as to insure perfect contact between screw and worm gear segment, even after years of use. The rotation of the screw moves the worm gear segment which, acting as a lever, always moves the body tube in the same direction, up or down, as a corresponding turn of the coarse adjustment heads. The spring above the lever always causes the teeth of the worm gear segment to engage the screw so that there can be no lost motion. Another excellent feature is the very positive stops for the screw. These stops are so constructed that. when the end of the adjustment is reached, the operating heads come to a definite stop. The same result takes. place at the opposite end of the adjustment, when the operating heads are reversed. These stops eliminate all possibility of wedging the screw. The adjustment ceases to act when the objective touches the cover glass. This form of adjustment is made in two degrees of sensitiveness. In the FS, FFS, FCS, FDS and APS, one complete rotation of the milled head moves the body tube 0.25 millimeter and in the CAS and DDS, one. rotation moves the tube 0.125 millimeter. In this latter form graduations are provided reading to 2.6 microns. 379 A RT AU R H. T H O M A 5 GO." (MEP AS SIND Fig. 1—Lever fine adjustment. Fig. 2—Side fine adjustment. Fig. 4—Complete substage. Substages. These are now furnished in two types designated by Bausch & Lomb as quick-acting screw form and the new complete substage with swinging device. The quick-acting screw substage, Fig. 3, consists of an arm with tube of standard size, into which a substage condenser, or other substage accessory, may be clamped and focused by means of a six-threaded screw. This gives a delicate and yet quick method of focusing. When the end of the thread has been reached, the arm with the condenser, diaphragm, etc., may be swung to one side, leaving the lower side of the stage entirely,free. Ample means are provided for accurate centering, and the thread - is protected from dust and injury. The new complete substage, Fig. 4 with centering device for condenser, offers advantages in simplicity of construction and convenience of manipulation over other substages. A heavy bar, rigidly attached to the stand, serves as a slide, upon which the substage proper is moved by means of a rack and pinion adjustment, and as a holder for the mirror and fork, which remain in a fixed position during the adjustment of the substage. Thus, when the illumination has once been centered by means of the mirror, no change is experienced when focusing the condenser, etc. The upper arm with centering device carries a ring of standard substage size, and this in turn will carry any of the Bausch & Lomb condensers, dark-ground illuminator or the swing-out condenser with self-locking upper iris, a clamp being provided to hold them. The advantage of this arrangement will be appreciated by those who are called upon to do a wide variety of work with frequent changes in accessories. The lower arm supports the condenser diaphragm. This mounting is so arranged that the diaphragm may be decentered for oblique illumination, may be oriented to bring the oblique pencil at any relation to the object, or may be swung entirely out of the optical axis. Substage Condensers. Abbe Condensers are neither chromatically nor spherically corrected, but for all ordinary work serve their purpose very well. Their function is to send light through the object under an angle sufficiently large to fill the aperture of the objective with light. They are furnished in two numerical apertures 1.20 N. A., containing two lenses with top lens removable, and 1.40 N. A., containing three lenses. The condenser mounts fit into the substage from below and are provided with an iris diaphragm, which controls the amount of light entering the condenser and the angle of the emitted cone. They are also provided with a swing-out carrier for holding a blue glass disc or a dark ground stop. The aplanatic condenser 1.40 N. A. consists of three lenses—an over-hemispherical, a meniscus and a double convex, which has a spheroidal surface for correcting the spherical aberration. The spherical correction obtained in this way is of the highest degree and perfect for all zones of the condenser, a result that has not been reached by any other construction. The lenses are separable, and the condenser, with the upper lens removed, gives a numerical aperture of 0.60; with both lenses removed, one of 0.40. The quality of correction in each case is of the same high order as that of the complete combination. When the numerical aperture of an objective is greater than 1.00, a drop of cedar oil should be placed between the upper lens surface of the condenser and the under surface of the slide. Otherwise the useful numerical aperture of the condenser will be limited to 1.00, and only a part of the full aperture of the objective will be utilized. An oil immersion of 1.30 N. A. will lose more than 10% of its efficiency, if the condenser is not immersed. Achromatic Objectives and Huyghenian Oculars. The tube length for which all of Bausch & Lomb objec- tives are computed is 160 mm (about 63 in.), reckoned from the upper end of the draw tube to the shoulder of the objective screw. The tube length may be accurately adjusted by means of the draw tube, which is graduated in single millimeters. The dry objectives are corrected for a cover-glass thickness of 0.18 mm, the mean thickness of No. 2 cover-glass, which we have found most practical for general use. For critical work, where an objective is expected to show all its efficiency, measured cover-glasses of 0.18 mm thickness should always be employed. This is very important, as a variation of 0.03 mm in the thickness of the cover-glass may destroy the spherical correc- tion, and with it the definition of the object. The influence of slight differences in the thickness of the cover-glass may be compensated for by increasing the tube length in case of too thin a cover-glass, and shortening for one too thick. The amount of compensation thus obtainable varies with the equivalent focus (E. F.) and the numerical aperture (N. A.) of the objective. Ina 4-mm objective of 0.85 N. A., for instance, an increase in tube length of 30 mm will balance a decrease in cover- glass thickness of 0.03 mm. 380 A RR TT H Us: R H. we SH OM “Ae 8s c 0 M P A N FY The performance of homogeneous immersion objectives is quite independent of variations in the thickness of cover-glass, as the refractive index of the immersion liquid (cedar oil) is practically the same as that of the cover- glass. On the other hand, the correct tube length (160 mm) must be very strictly adhered to, a variation of 5 mm being sufficient to destroy the perfection of the image. Unless higher power objectives (from 8 mm up) are tested under the circumstances for which they are corrected—160 mm tube length and 0.18 mm cover-glass—the best results cannot be expected. This should be borne in mind especially when comparisons are made with objectives of other makes on slides with unknown cover-glass thickness. The finer the corrections and the adjustment of an objective, the more sensitive it is to any change in the conditions mentioned above. The huyghenian oculars are marked according to their magnification when used as magnifiers. This is equal to the distance of distinct vision for a normal eye (250 mm or 10 in.), divided by the focus of the ocular. The lower focal point in this series of oculars is situated somewhat higher than usual, thereby increasing the optical tube length—the distance between the upper focus of the objective and the lower focus of the ocular. The magnifications obtainable with these oculars are therefore greater than those obtained with the usual oculars of the same equivalent focal length. The whole series of oculars is par-focal, that is the lower focal planes of all lie at the same distance below the eye-lens, so that in interchanging them only a very slight change of the fine adjust- ment is necessary. Apochromatic Objectives and Compensating Oculars. The superiority of the apochromatic objectives over the achromatics lies in the finer color correction of the former. While in the achromatic objectives the chromatic aberration is corrected for two colors and the spherical aberration generally for one, in the apochromatic objectives the chromatic correction is accomplished for three and the spherical for two colors, which means that practically all the images produced by the different colors of the spectrum lie in the same plane and are equally sharp. The necessary consequence is a higher efficiency for the apochromat, which manifests itself by the absence of color halo when focusing with central illumination on a black and white object and by the appearance of such an object (Abbe test plate) under oblique illumination. While the image by the achromat under the latter circumstances is fringed by heavy borders of color, the image produced by the apochromat has just barely noticeable fine color fringes of tertiary nature. White objects like diatoms, plant sections, etc., are rendered in their natural white while the achromat will show them in the yellowish or greenish hue of the color for which the spherical aberration is corrected. Although the differently colored images lie in the same plane they are of different sizes which, with ordi- nary oculars, would give color fringes in the margin of the field. This difference is, however, neutralized by com- pensating oculars so that the combination of apochromatic objective and compensating ocular gives a field free from color to the very margin. These compensating oculars also work very well with achromatic objectives whose focal length is 8 mm or less but are not satisfactory when used with the lower powers. The fact that the violet rays are brought to the same focus as the visual rays makes these objectives excellent for photographic use, both for white light and for monochromatic light. It is imperative for obtaining best results with apochromatic objectives that the tube length of 160 mm is constantly maintained, also that the 8 mm and 4 mm, which are mounted with correction collar, are carefully adjusted for the thickness of cover-glass used. Numerical Aperture and Depth of Focusing. Resolving power is the property by which an objective shows distinctly separated two small elements in the structure of an object, which are only a short distance apart. The measure for the resolving power is the numerical aperture (N. A.). The higher the N. A. the greater the resolving power of the objective and the finer the detail it can reveal. N. A. is given by the formula: N. A. =msin wu wherein . ae n =the lowest refractive index that appears between the object and the front lens of the objective and u =half the angular aperture of the objective. _ : ; If a very narrow central pencil is used for illumination, the finest detail that can be shown by a micro- / scope, with high enough magnification, is equal tow where 7 is the wave length of the light used for illumination. The wider the pencil used for illumination, the greater the resolving power, until a maximum is reached, when the width of the pencil is sufficient to fill the whole aperture of the objective. In this case the resolving power is twice A as great, the finest detail that the objective can show being now equal to =>": This same limit is reached when a narrow pencil of greatest possible obliquity is used. For example, the wave length of the brightest part of the spectrum may be assumed to canal de mm. Consequently an objective of N. A. equal to 1.00 will resolve two lines separated by a distance ra =0.00053, with a narrow central illuminating cone, and = 0.000265, with a cone filling the whole aperture, or with a narrow oblique cone. ; , ee The 4-mm, 0.85 N. A. objective will resolve lines separated by distances ranging between 0.00062 and 0.00031, dependent upon the aperture employed. For the 4-mm, 0.65 N. A. objective the limiting values are 0.00081 and 0.000405. The N. A. can also be expressed by the equation d effective aperture of back lens Maite = af. 2 X equivalent focus Two objectives of the same equivalent focal length and the same N. A. should show the same illuminated area in the back lens, when viewed without an ocular and illuminated with the widest cone of light ake in. : ee ne canine foregoing explanation shows the importance of the N. A. to the efficiency of an objective. It also is evident that an objective cannot show its full efficiency if it is not used with a condenser of an N. A. large enough to fill the back of the objective with light. ; : ; a Depth of focus (known also as depth of sharpness or penetration) is another important factor which is often not clearly understood. It depends on the N. A. and the magnification and is inversely proportional to both. The higher the N. A. and the higher the magnification, the less the depth of focus. It is beyond the power of the optician to change these conditions. Every effort aiming at an increase of the depth of focus, for example, by inserting diaphragms above the back lens of the objective must necessarily decrease the effective diameter of the back lens and thus decrease the N. A., thereby lowering the efficiency of the objective. 381 6600. 6601. 6602. 6603. 6604. 6605. El F AND FF MICROSCOPES, WITH LEVER FINE ADJUSTMENT, Bausch & Lomb. Recommended for all educational laboratory work because of the facility and the safety with which the arm of the microscope may be grasped with the whole hand, and the large amount of space available for manipulation of the object on the stage, and the unquestioned durability of this type of lever fine adjustment in the hands of students. Base—M odified horseshoe form, of rounded contour. hae Pillar—One piece with base; provided with broad, double-bearing inclination joint, having vertical and horizontal stops. Arm—Long curved form with rounded edges, of rugged construction to withstand laboratory usage; provides maximum space for manipulation of object. Body Tube—Outside diameter, 35 mm; provided with society screw thread; standard size oculars are used; draw tube graduated in single millimeters with every tenth line numbered, adjustable in lined sleeve, or in metal fitting, if so specified, and pro- vided with society screw thread. Focusing Adjustment—Coarse adjustment by standard rack and pinion, provided with stop to prevent pinion from overriding rack; fine adjustment of Bausch & Lomb original lever type with milled head, ceasing to operate when objective touches slide; adjustment head locked to prevent removal; all parts of fine adjustment thoroughly dust-proof. Stage—Of metal, completely covered with vulcanized rubber except at point of attachment; measures 102 x 102 mm, with distance of 76 mm from center to arm at stage surface (distance from optical center to extreme inner curve of arm, 85 mm); provided with spring clips and an iris diaphragm with mount having screw thread for attaching a substage ring to hold an Abbe condenser; iris diaphragm controlled by milled ring, operated from any point of its circumference; stage attached to arm on broad bearing surface to insure maximum rigidity. Mirror—Plane and concave, 50 mm in diameter; adjustable in two planes in a fork, mounted on swinging arm for oblique illumina- tion and provided with stop for central illumination; mirror not easily removable. Finish—Body tube in alcohol-proof black; base, pillar and arm in black crystal finish, aleohol-proof; pinion and fine adjustment heads in yellow. Case—Of hard wood with polished finish; fitted with brass lock and key. Substage of F Models—No substage is regularly supplied with F Microscopes. ring is provided to carry same Substage of FF Model—Adjustable for focus by quick-acting screw; consists of tube for condenser, which comes into plane of stage when screw is turned up as far as possible, allowing condenser to be used in immersion contact with slide; condenser is provided with iris diaphragm beneath; substage is swung to left of optical axis when screw reaches limit of motion down- Where Abbe condenser is supplied, as in F6, a suitable ward. Achromatic Objectives B. & L. A Huyghenian Abbe No. Dry Oil Immersion Oculars Nosepiece Condenser Price F2 16mm 4mm 7.5 Circular Double 60.50 F4 16mm 4mm 5x 10 Circular Double 63.00 F6 16mm 4mm 5x 10 Circular Double 1.20 N. A. 76.00 FF6 16mm 4mm 5X 10 Circular Double 1.20 N. A. 84.00 FF8 16mm 4mm 1.9 mm 1.25N.A. 5X 10 Circular Triple 1.20 N. A. 128.50 FF10 16mm4mm “7*1.9mm 1.30 N.A. 5x 10 Circular Triple 1.20 N. A. 141.50 * The 1.9 mm, 1.30 N. A. Oil Immersion Objective supplied with outfit FF-10 is the new Fluorite Objective No. 6726 described on page 395. For description of optical properties and working limitations of various objectives, see pages 380 and 381. 382 6608 6612 FS AND FFS MICROSCOPES, WITH LEVER SIDE FINE ADJUSTMENT, Bausch & Lomb. With the increasing popularity of the side fine adjustment, the FFS8 Microscope has become the standard instrument both for physicians’ private and institutional laboratory work in medicine and allied sciences, and also in the Medical Department of the U. 8S. Army and other Government departments. 6608. 6609. 6610. 6611. 6612. 6613. Base—Modified horseshoe form, of rounded contour. Pillar—One piece with base; provided with broad, double-bearing inclination joint, having vertical and horizontal stops. Arm—Long curved form with rounded edges, of rugged construction to withstand laboratory usage; provides maximum space for manipulation of object. Body Tube—Outside diameter, 35 mm; provided with society screw thread; standard size oculars are used; draw tube graduated in single millimeters with every tenth line numbered, adjustable in lined sleeve, or in metal fitting, if so specified, and provided with society screw thread. Focusing Adjustment—C oarse adjustment by standard rack and pinion, provided with stop to prevent pinion from overriding rack; side fine adjustment of lever type, with micrometer head on each side of arm; complete rotation of micrometer heads pro- duces vertical movement of 0.25 mm, always in same direction as coarse adjustment heads; fine adjustment ceases to operate when objective touches slide; positive stops denote upper and lower limits; automatic take-up for wear is provided, and all parts of fine adjustment are dust-proof. Stage—Of metal, completely covered with vulcanized rubber except at point of attachment; measures 102 x 102 mm, with distance of 76 mm from center to arm at stage surface (distance from optical center to extreme inner curve of arm, 85 mm); _ pro- vided with spring clips and an iris diaphragm with mount having screw threads for attaching a substage ring to hold an Abbe condenser; iris diaphragm controlled by milled ring, operated from any point of its circumference; stage attached to arm on broad bearing surface to insure maximum rigidity. Mirror—Plane and concave, 50 mm in diameter; adjustable in two planes in a fork, mounted on swinging arm for oblique illumina- tion and provided with stop for central illumination. Finish—Body tube in alcohol-proof black; base, pillar and arm in black crystal finish, alcohol-proof; pinion and fine adjustment heads in yellow. Case—Of hard wood with polished finish; fitted with brass lock and key. Substage of FS Models—No substage is regularly supplied with FS Microscopes. Where Abbe Condenser is supplied as in FS6, a suitable ring is provided to carry same. Substage of FFS Models—Adjustable for focus by quick-acting screw; consists of tube for condenser, which comes into plane of stage when screw is turned up as far as possible, allowing conde 2nser to be used in immersion contact with slide; condenser is provided with iris diaphragm beneath; substage is swung to left of optical axis when screw reaches limit of motion down- ward. Achromatic Objectives B. & L. . \ Huyghenian Abbe No. Dry Oil Immersion Oculars Nosepiece Condenser Price FS2 16mm 4mm 7.5% Circular Double 64.00 FS4 16mm 4mm 5X 10 Circular Double 66.50 FS6 16mm 4mm 5x 10% Circular Double 1.20 N. A. 79.50 FFS6 16mm 4mm 5x 10 Circular Double 1.20 N. A. 87.50 FFS8 16mm 4mm 1.9 mm 1.25N.A. 5X 10X Circular Triple 1.20N.A 132.00 FFS10 16mm 4mm *1.9 mm 1.30N.A. 5X 10 Circular Triple 1.20N.A 145.00 *The 1.9 mm, 1.30 N. A. Oil Immersion Objective supplied with outfit FFS-10 is the new Fluorite Objective No. 6726 described on page 395. For description of optical properties and working limitations of various objectives, see pages 380 and 381. 383 6615 6619 FCS AND FDS MICROSCOPES, WITH LEVER SIDE FINE ADJUSTMENT, Bausch & Lomb. These microscopes are of exactly the same construction as FFS except as to stage, which is of the circular, revolving type instead of rectangular. 6614. 6615. 6616. 6618. 6619. 6620. Base—M odified horseshoe form, of rounded contour. Pillar—One piece with base; provided with broad, double-bearing inclination joint, having vertical and horizontal stops. Arm—Long curved form with rounded edges, of rugged construction to withstand laboratory usage; provides maximum space for manipulation of object. Body Tube—Outside diameter, 35 mm; provided with society screw thread; standard size oculars are used; draw tube graduated in single millimeters with every tenth line numbered, adjustable in lined sleeve, or in metal fitting, if so specified, and provided with society screw thread. Focusing Adjustment—Coarse adjustment by standard rack and pinion, provided with stop to prevent pinion from overriding rack; side fine adjustment of lever type, with micrometer head on each side of arm; complete rotation of micrometer heads pro- duces vertical movement of 0.25 mm, always in same direction as coarse adjustment heads; fine adjustment ceases to act when objective touches slide; positive stops denote upper and lower limits; automatic take-up for wear is provided, and all parts of fine adjustment are dust-proof. Stage of FCS Models—Circular, revolving, of metal with vulcanite top, 125-mm diameter, with a distance of 76 mm from center to arm; provided with centering screws and spring clips. Removable for substitution of revolving mechanical stage. Stage of FDS Models—Circular, revolving, combined mechanical and plain, with centering screws; 125-mm diameter, with a distance of 76 mm from center to base of arm; provided with two rack and pinion movements covering range of 75 mm and 33 mm respectively; pinion heads close together in fixed relative position at all times. Stage construction allows easy removal of the mechanical stage only, and the groove left open is filled with a tightly fitting piece converting the stage to a plain surface for using the stage clips. Substage—Adjustable for focus by quick-acting screw; consists of tube for condenser, which comes into plane of stage when screw is turned up as far as possible, allowing condenser to be used in immersion contact with slide; condenser is provided with iris diaphragm beneath; substage is swung to left of optical axis when screw reaches limit of motion downward. Mirror—Plane and concave, 50 mm in diameter; adjustable in two planes in a fork, mounted on swinging arm for oblique illumina- tion and provided with stop for central illumination. Finish—Body tube in alcohol-proof black; base, pillar and arm in black crystal finish, alcohol-proof; pinion and fine adjustment heads in yellow. Case—Of hard wood with polished finish; fitted with brass lock and key. Achromatic Objectives B.&L. - ~ Huyghenian Abbe No. Dry Oil Immersion Oculars Nosepiece Condenser Price FCS6 16mm 4mm 5x 10 Circular Double 1.20 N. A. 109.00 FCS8 16mm4mm_— 1.9mm 1.25N.A. 5X 10X Circular Triple 1.20N.A. 153.50 FCS10 16mm4mm 7*1.9mm 1.30N.A. 5X 10X Circular Triple 1.20N.A. 166.50 FDS6 16mm 4mm 5X 10 Circular Double 1.20N.A. 145.00 FDS8 16mm 4mm 1.9mm 1.25N.A. 5X 10X Circular Triple 1.20N.A. 189.50 FDS10 16mm4mm_ “*1.9mm 1.30N.A. 5X 10 Circular Triple 1.20 N.A. 202.50 *The 1.9 mm, 1.30 N. A. Oil Immersion Objective supplied with outfits FCS-10 and FDS-19 is the new Fluorite Objective No. 6726 described on page 395. For description of optical properties and working limitations of various objectives, see pages 380 and 381. 384 A R T H U_R H. T H O M A S$ Cc O M P A N _ Y 6622 CAS MICROSCOPE, WITH LEVER SIDE FINE ADJUSTMENT, Bausch & Lomb. Designed for individual use in research. This stand differs from the smaller models in size and in the following principal specifications: 6622. 6623. 6624. 6625. Focusing Adjustment—Coarse adjustment by standard rack and pinion, provided with stop to prevent pinion from overriding rack; side fine adjustment of lever type with micrometer head on each side of arm—one with drum graduated to read 2.5 microns of vertical movement; complete rotation of micrometer heads produces vertical movement of 0.125 mm, always in same direction as coarse adjustment heads; fine adjustment ceases to operate when objective touches slide; positive stops denote upper and lower limits; automatic take-up for wear is provided, and all parts of fine adjustment are dust-proof. Stage—Of metal, completely covered with vulcanized rubber, except at point of attachment; measures 116 x 108 mm, with distance of 87 mm from center to arm at stage surface; provided with spring clips. Substage—Complete with swing-out condenser. This new complete substage offers advantages in simplicity of construction and convenience of manipulation over others of similar type. A heavy bar, rigidly attached to the stand, serves as a slide upon which the substage proper is moved by means of a rack and pinion adjustment, and as a holder for the mirror and fork, which remain in a fixed position during the adjustment of the substage. Thus, when the illumination has once been cen- tered by means of the mirror, no change is experienced when focusing the condenser, etc. The upper arm with centering device carries a ring of standard substage size, and this in turn will carry any Bausch & Lomb condenser, dark-ground illu- minator or the swing-out condenser with self-locking upper iris, a clamp being provided to hold them. The lower arm supports the condenser diaphragm. This mounting is so arranged that the diaphragm may be decentered for oblique illumination, may be oriented to bring the oblique pencil at any relation to the object, or may be swung entirely out of the optical axis. Finish—Body tube and arm in alcohol-proof black; base and pillar in black crystal finish, alcohol-proof; other parts in yellow. Case—Of hard wood with polished finish; fitted with brass lock and key. Achromatic Objectives B. & L. A ‘ Huyghenian Abbe No. Dry Oil Immersion Oculars Nosepiece Condenser Price CAS8 16mm 4mm 1.9mm 1.25N.A. 5X 10 Circular Triple 1.20N.A. 192.00 CAS10 16mm4mm *1.9mm 1.30N.A. 5X 10X Circular Triple 1.20N.A. 205.00 Apochromatic Objectives B&L. ;- . Compensating Abbe No. Dry Oil Immersion Oculars Nosepiece Condenser Price CAS14 16-mm 4-mm 7.5 12.5% Circular Double 1.40 N. A. 214.50 CAS18 16mm4mm 2mm 1.30 N. A. 7.6% 12.5% Circular Triple 1.40 N.A. 297.00 *The 1.9 mm, 1.30 N. A. Oil Immersion Objective supplied with outfit CAS—10 is the new Fluorite Objective No. 6726 described on page 395. For description of optical properties and working limitations of various objectives, see pages 380 and 381. 885 TE OU) OR H. TE OM AS Cc O M P A N Y U B B B zB B 2B 6626 DDS MICROSCOPE, WITH LEVER SIDE FINE ADJUSTMENT, Bausch & Lomb. With large body tube for photomicrography, and with large revolving mechanical stage. Designed for individual use in research and for photomicrography, particularly with Camera GP, as described on page 420. Similar in finish and con- struction to CAS and preceding models, excepting in the following principal specifications: 6626. 6627. 6628. 6629. Pillar—Double rectangular in section; provided with broad, double-bearing inclination joint and clamping lever to secure instrument in any position, having stops in vertical and horizontal positions. Body Tube—Outside diameter, 50 mm; provided with society screw thread; standard size oculars are used; draw tube graduated in single millimeters with every tenth line numbered, adjustable in lined sleeve, or in metal fitting, if so specified, and pro- vided with society screw thread; lower collar may be removed for attaching the Micro-Tessar, 72-mm objective. (See No. 7110. Focusing Adjustment—Same as in CAS, described on page 385, i. e., with fine adjustment drum graduated to read 2.5 microns of vertical movement; complete rotation yielding a vertical movement of 0.125 mm. Stage—Large mechanical, circular, with centering screws; removable, with clamping device to prevent rotation when desired; 125 mm in diameter with distance of 87 mm from center to base of arm; provided with two rack and pinion movements covering a range of 75 mm and 50 mm, respectively, permitting the examination of 75 x 50 mm slides from corner to corner; upper part of stage may be removed, leaving a large flat surface with one rack movement; entire mechanical stage removable for substitution of plain revolving stage. Substage—Complete with swing-out condenser, as described in CAS on page 385. Mirror—Plane and concave, 50 mm in diameter; adjustable in two planes in a fork; attached in fixed position to substage support. Finish—Lower parts, arm and body tube in alcohol-proof black; other parts in yellow. Base and pillar are not now finished in black crystal as shown in illustration. Case—Of hard wood with polished finish; fitted with brass lock and key. Achromatic Objectives B. & L. fs . Huyghenian Abbe No. Dry Oil Immersion Oculars Nosepicce Condenser Price DDS8& 16mm 4mm 1.9mm 1.25N.A. 5X 10X Circular Triple 1.20N.A. 270.00 DDS10 16mm4mm *1.9mm 1.30N.A. 5X 10X Circular Triple 1.20N.A. 283.00 Apochromatic Objectives B. & L. , Compensating Abbe No. Dry Oil Immersion Oculars Nosepiece Condenser Price DDS14 16mm 4mm 7.5% 12.5 Circular Double 1.40N. A. 292.50 DDS18 16mm 4mm 2mm 1.30 N. A. 7.5% 12.5% Circular Triple 1.40N.A. 375.00 *The 1.9 mm, 1.30 N. A. Oil Immersion Objective supplied with outfit DDS-10 is the new Fluorite Objective No. 6726 des- cribed on page 395. For description of optical properties and working limitations of various objectives, see pages 380 and 381. 386 6643 AP AND APS PORTABLE MICROSCOPES, WITH LEVER SIDE FINE ADJUSTMENT, Bausch & Lomb. This microscope was originally designed for use by the International Health Board of the Rockefeller Foundation for their field work. Recommended for all uses where portability is an important consideration. 6640. 6641. 6642. 6643. 6644. Base—Folding, with each arm turning on its own center. Pillar—Rounded, of one piece with arm. Arm—New handle type, with rounded edges; provides ample space for manipulation of object. Body Tube—Outside diameter, 35 mm; provided with society screw thread; standard size oculars are used; draw tube graduated in single millimeters with every tenth line numbered, adjustable in lined sleeve, or in metal fitting, if so specified. Focusing Adjustment—Coarse adjustment by standard rack and pinion, provided with stop to prevent pinion from overriding rack; side fine adjustment of lever type, with micrometer head on each side of arm; complete rotation of micrometer heads pro- duces vertical movement of 0.25 mm, always in same direction as coarse adjustment heads; fine adjustment ceases to act when objective touches slide; positive stops denote upper and lower limits; automatic take-up for wear is provided, and all parts of fine adjustment are dust-proof. Of metal, completely covered with vulcanized rubber except at point of attachment; measures 92 x 76 mm, with distance of 62 mm from center to base of arm; provided with spring clips. Mirror—Plane and concave, 50 mm in diameter; adjustable in two planes ina fork, mounted on swinging arm for oblique illumination. Finish—Body tube, with connections, draw tube and substage in alcohol-proof black; base, pillar and arm in black crystal finish, alcohol-proof; pinion and fine adjustment heads in yellow. Case—Of hard wood with polished finish; fitted with brass lock and key; dimensions, 263 x 162 x 95 mm (1034 x 62 x 334 in.). Weight—APS in carrying case, 8 lbs., 714 ozs. Substage of AP2 and AP4—No substage is regularly supplied with these models. Substage of APS6, APS8 and APS10—Adjustable for focus by quick-acting screw; consists of tube for condenser, which comes into plane of stage when screw is turned up as far as possible, allowing condenser to be used in immersion contact with slide; condenser is provided with iris diaphragm beneath; substage is swung to left of optical axis when screw reaches limit of motion downward. Stage Achromatic Objectives B. & L. Huyghenian Abbe No. Dry Oil Immersion Oculars Nosepiece Condenser Price AP2 16mm 4mm 7.5 Circular Double 70.00 AP4 16mm 4mm 5 10 Circular Double 72.50 APS6 16mm 4mm 5 10 Circular Double 1.20 N. A. 93.50 APS&S 16mm 4mm 1.9mm 1.25N.A. 5X 10 Circular Triple 1.20N.A. 138.00 APS10 16mm4mm *1.9mm 1.30N.A. 5x 10 Circular Triple 1.20 N.A. 151.00 *The 1.9mm, 1.30 N. A. OilImmersion Objective supplied with outfit APS-10 is the new Fluorite Objective No. 6726 described on page 395. For description of optical properties and working limitations of various objectives, see pages 380 and 381. == The merchandise listed in this catalogue originates in some 1200 different establishments. The selection is based upon thirty years of experience in the supply of apparatus and reagents to chemical, metallurgical and biological laboratories and has been made with painstaking care. 387 AS OR oT ve CUS GR: H. T H O M 6458 FSM METALLURGICAL MICROSCOPE, Bausch & Lomb, especially designed for and widely used in met- allography or in any other opaque microscopic work requiring the use of a Vertical Illuminator and focusing stage. In general construction, the microscope is identical with the FS type with lever side fine adjustment, except in the specifications mentioned below. This microscope is recommended for use with Camera RS, as shown in the illustration of this outfit on page 372. ; Stage—Adjustable vertically by standard rack and pinion to increase working distance and allow focusing without displacing vertical illuminator with reference to light; circular, 78 mm in diameter, with a distance of 70 mm from center to base of arm; aper- ture 40 mm in diameter; of metal with vulcanite top; provided with. centering screws and spring clips; removable for substitution of attachable Mechanical Stage No. 6470. Vertical Illuminator—No. 6464, consisting of a plane glass reflector, full circle, so mounted as to be readily adjusted by means of a head at the side. The reflector carrier is mounted on a slide providing for centering. 6458. Microscope FSM1, as above described, with 16 mm and 4 mm objectives in regular size mounts, the 4-mm objective specially corrected for uncovered objects; 5X ocular and vertical illuminator No. 6464, incase: withlock-ard keys fox. seece Mos tes va Bevin Sanat pence ge Men umes G18 wean Sah ya nee eae 198.00 6459. Microscope FSM§9, identical with No. 6458, but with the addition of one 10 ocular, one 32-mm objec- tive in short mount and No. 6470 Mechanical Stage, specially designed for metallographic work and described and illustrated on page 370... 0.0.0.0... 20000000 ccc cece tees 249.00 M CHEMICAL MICROSCOPE, Bausch & Lomb.* A laboratory microscope of wide application since it can be conveniently utilized both for the examination of chemical crystals by polarized light, for the examination of metallurgical and other opaque specimens and for ordinary work by transmitted light, as in bacteriology. For opaque work the revolvable stage is removed and Auxiliary Stage No. 6653 is fitted in its place, by which change a focusing stage is provided. For bacteriological work, the polarizer is removed and replaced with a usual Abbe Condenser, and the regular oil-immersion objective attached to the quick-changing Nosepiece No. 6822. Stage—Circular, revolving, with milled edge, graduated on circumference in single degrees, with every tenth line numbered, and read by conveniently placed pointer; measures 88 mm outside and 87 mm inside graduations, with distance of 58 mm from center to base of arm; has vulcanite top and is provided with spring clips and centering screws. Substage—Adjustable for focus by quick-acting screw of long range; consists of mounting for polarizer, which is swung to left of optical axis when screw reaches limit of motion downward. Analyzer—Consists of Thompson prism mounted in revolving collar graduated in two-degree divisions, with every tenth line num- bered; collar revolves smoothly in cylindrical mounting fitting over draw tube and is slotted to engage stud for zero point; can be easily removed for insertion of microscope ocular. Polarizer—Consists of high-grade Nicol prism, mounted with revolving ring graduated in two-degree divisions, with every tenth line numbered, and having an indicating pointer; entire mounting securely supported in substage and fixed for zero point by stud which engages corresponding slot. B. & L. Cross Hair Quick Changing No. Objectives, Dry Oculars Nosepiece Price 6650. M1 16mm 8mm 10x 12.5x 140.00 6651. M2 16mm 8mm 10x 12.5 With two rings 151.00 6652. M4 32mm 16mm 8mm { ae oo } With three rings 174.50 6653. Auxiliary Stage, fitting substage for use in metallurgical work.................... 0-0-0005 6.25 * After the design of Dr. E. M. Chamot, Cornell University. 388 Dae ere Corba 6657 KA (GREENOUGH TYPE) BINOCULAR MICROSCOPE, Bausch & Lomb. This is the most satisfac- tory binocular arrangement for low power work. Because of the use of separate objectives it is not advisable to use objectives of less than 24-mm focal length, affording with a 10 ocular a total magnification of an actual field of 2 mm, of 74. Arm—Embodies two special features: (1) provides for extraordinary range of working distance up to 155 mm, measuring from lower edge of nosepiece to stage; curved part is adjustable along upright and can be clamped in any position by clamping head shown in opening of curved part; working distance can also be decreased by detaching curved part from upright and body tubes, inverting and replacing it, for focusing some distance beneath stage (as when used on stand KN, see page 390; (2) entire arm with body tube can be removed and used on stand KN. Body Tubes—Combination of two microscope tubes, the upper parts of which are fitted with Porro prisms and are rotatable for adjusting position of oculars to observer’s pupillary distance; one image merges with the other, and object is seen stereo- scopically, erect and not transposed; nosepiece provided takes self-centering slides, upon which each pair of objectives is mounted with means for centering one with the other, but when the instrument leaves the factory the objectives are properly centered. Focusing Adjustment—Standard rack and pinion; pinion heads placed with relation to body tubes so as to eliminate completely inconvenience caused where these parts are close together; location of rack slide such that it is not immersed when working with water immersion objectives. Stage—Of metal with large rectangular aperture provided with two removable plates; one of glass, 80 x 95 mm, the other of metal, same size, with aperture 22 mm in diameter, underneath which a rotating plate provides white opaque, black opaque and ground-glass stops, or clear aperture; provided with detachable metal hand rests and spring clips. Mechanical Stage No. 6828 can be attached by slight modification of the microscope stage. ‘ Mirror—Plane and concave, 50 mm in diameter; adjustable in two planes in a fork, mounted on swinging arm; mirror not easily removable. Case—Of hard wood with polished finish; fitted with brass lock and key. B. & L. i: No. Paired Objectives Paired Oculars Price 6656. KAI 40 mm 10 108.00 6657. KA3 48 mm 32 mm 6.4 X 10 133.00 6658. KA5 55mm 40mm 24mm 5x 7.5 10x 158.00 6659. Stage or Fork, taking plates 96 x 135 mm, for use in place of regular stage...................... 18.00 K BINOCULAR MICROSCOPE, Bausch & Lomb. This microscope is identical with type KA, but with- out base, for examination of objects too large to be placed on microscope stage, but which can be examined with incident light. Widely used in entomological work, and in industrial laboratories for examination of wood, metal, leather, paper, etc. The price includes a suitable carrying case. Baa Paired Objectives Paired Oculars Price K1 40 mm 10x 98.00 he K3 48mm 32 mm 6.4 x 10x 123.00 6662. K5 55 mm 40mm 24mm 5x 7.5% 10X 148.00 389 AY ORS 9 T—-Ay UPR FL T H O M A _ 8 C O M P A N Y 7: Ej 2 Ej 6664 6670 KC BINOCULAR MICROSCOPE, Bausch & Lomb. This microscope consists of binocular body KA with support arm mounted on a special support to clamp on the edge of table, as designed by Prof. J. H. Schaffner, of Ohio State University, for the observation of herbarium sheets. It has also been found very useful in zodlogical work for the examination of specimens in dissecting pans, on glass plates, etc. The instrument is offered com- plete with new support, and the new support is offered separately for those who are already provided with the KA Binocular Microscope. The dimensions of the arm permit for working distances up to 195 mm, measuring from the lower edge of the nosepiece to table top. 6664. Clamp Stand KC1, as above described, with microscope body KA, paired objectives 40 mm, and paired oculars) 10.x3and! casetor body “onlyinin24 se icles Samia an glen Bh et ae oe ee ee oe 102.00 6665. Clamp Stand KC3, with microscope body KA, paired objectives 55 mm and 40 mm, and paired oculars 64 TERMINALS Fig. 4. Silverman Illuminator, showing Tungsten Fig. 6. Silverman Illuminator, lamp as seen from below. with adapter attached to stage of a attached to objective of a monoc- binocular microscope. ular microscope. SILVERMAN ILLUMINATOR (Patented), for use with ordinary Monocular and Binocular, or special Metallurgical Microscopes, for the examination and photography of opaque and semi-opaque objects. This is a simple device consisting of a circular tungsten lamp, surrounding and conveniently attachable to the objective of an ordinary monocular microscope, which furnishes a diffused and uniform illumination of the stage area covered by the field of the objective, with a silvered reflector throwing the light inward and downward on the specimen on the microscope stage. A baked enamel coating protects the silvered reflector and prevents any light Delng (Oren from the lamp into the observer’s eye. The circular lamp bulb is furnished either colorless or Day- ite glass. The lamp operates at about 0.9 amperes at 13.5 volts for visual observation and for focusing, but during photographic exposures should have 1.06 amperes at 18 volts as may be conveniently arranged through the adjust- able rheostat supplied with the outfit. The illuminator is conveniently held in place on the objective of the microscope by means of concentric fingers operated by two small handles and a spring. When used to illuminate the field of a binocular (two-objec- tive) microscope, a special support is provided which clamps to the stage of the binocular microscope as shown in Fig. 5. Ashutter (Fig. 2) is provided to cut off about one-half of the light source, causing an appearance of oblique illumination valuable for the examination of certain specimens. An absorption disc (Fig. 3) is also provided with hole in the center to be laid on the specimen when the illuminator is used with very low power. It prevents reflec- tion of the light back into the microscope tube from parts of the polished surface outside the field of the microscope. As the Silverman illuminator remains in a fixed position on the objective and, therefore, is raised and low- ered with the body tube in focusing, no vertical illuminator with its outside source of light or a focusing stage is required for the examination of opaque specimens and as is provided with metallurgical microscopes as designed for this purpose. e a addition to the examination of metallurgical specimens, the attachment has found convenient use in the examination of opaque specimens as is provided with metallurgical microscopes as designed for this purpose. In addition to the examination of metallurgical specimens, the attachment has found convenient use in the examination of textiles, paper, rubber, refractories, insulating materials, linoleum compositions, etc., and plant pathology. Bie : : : See Alexander Silverman, “A New Method of Microscope Illumination,’ Metallurgical and Chemical Engi- neering, March 15, 1918; “A New Illuminator for Microscopes,” The Journal of Industrial and Engineering Chem- istry, December, 1918; “A New Microscope Illuminator,” Transactions of the Faraday Society, Vol. XVI, 1920, and “A New Departure in Photomicrography,” Journal of the Society of Chemical Industry, Vol. XXXVIII, pp. 126, 127, May 31, 1919. 6880. Silverman Illuminator (Patented), as above described, consisting of one lamp holder for monocular micro- scope, Fig. 4, two tungsten lamps of colorless glass to fit same, one stage adapter, Fig. 1, for use with binocular microscope, one shutter, Fig. 2, one absorption disc, Fig. 3, and with rheostat (not shown in illustrations) with double button snap switch and a one-button contact key; the switch controls the current for visual observation and the contact key is intended to be held down during photographic exposure. For 110 volts.............. 2.0.00 cece eee eee 45.00 6881. dittoxbut tor 22 OVoltsic0s Netcare n cies eine eee nt alls £ ee baie Nia a essence MASS OA Eye 45.00 6882: “Lamp, only; of colorless:glass\¢ eui4:.. space Ree hae eas on P apes tun ea Gage area eee ape ane 4.00 6883. a GES TY AVI IGO: CLASS re. a tasauscesearetanaed a bat eh a Sts at av cara tautomer apnea ae somite voce Mh cean va tea ee Nba See a 4.50 i ac h 6891 MICROSCOPE, ZEISS STAND III. This is the most popular of the modern series of Zeiss Microscopes. For all ocular observations, it meets the requirements of the most refined investigations, but is not recommended for use in micro-photography or micro-projection because of the narrow or standard tube. We stock this Stand with two stage arrangements as follows: Stand IIICA, with a non-revolving stage fitted with a movable plate giving a backward and forward movement by operating two screws jointly, and a transverse movement by operating the same screws in opposite directions; with a total range of dis- placement of about 10 mm. This arrangement has been found in practice to be as convenient in most routine use as the large revolving mechanical stage. Stand IIE is fitted with the large revolving mechanical stage with center housing, exactly as illustrated with stand IB, This stage has a range of motion of 50 mm in one direction and 35 mm in the other, with a third scale and vernier showing the position of the movable stop for the object slide. Both Stands are furnished with complete Abbe illuminating apparatus with condenser of 1.40 N. A. These condensers are so mounted that the two front lenses can be removed, permitting the remaining lens to serve as a long focus condenser of small aperture for use with objectives of low power. When these condensers are used up to their full aperture with objectives of wide angle, the space between the condenser and object slide should be filled with immersion oil. 6890. Microscope, Stand IIICA, with simplified, non-revolving mechanical stage and complete Abbe illumina- ting apparatus with condenser of 1.40 N. A.; without nosepiece, objectives or oculars. In MN AN OLANVACASCk cs cw cee ented ta, ee eee naam Succes na Sieah mest anemia § eC at rh led Sur apucca stats 116.00 6891. ditto, but with triple revolving nosepiece and achromatic outfit consisting of objectives A of 18 mm focus, D of 4.4 mm focus, 142 inch fluorite homo-immersion objective of 1.30 N. A., and huy- ghenian oculars 2 and 4. Complete in mahogany case.........0... 0... c ccc cece cee eees 217.00 6892. ditto, but with apochromatic outfit consisting of dry apochromatic objectives of 16.2 mm and 4.3 mm and 2 mm homo-immersion objective of 1.30 N. A., with compensating oculars 6 and 12. Com- Dlete ln mahogany Cases sescccjere sce Ses easue te ool taceots ders art ioe singh ha ter che antten ee cae nee eed a mane ws 309.50 6893. Microscope, Stand IIIE, with large revolving mechanical stage, complete Abbe illuminating apparatus with condenser of 1.40 N. A., as above described, but without nosepiece, objectives or oculars. In mahog- ETA CAS Cea retclainteishyaye esccies heats ely Baie tase areata Aare Groce tO Reise eh Sea ayo de tet ainlats aespten tee nih att Oe 160.00 6894. ditto, but with triple revolving nosepiece and achromatic outfit consisting of objectives A of 18 mm focus, D of 4.4 mm focus, 142 inch fluorite homo-immersion objective of 1.30 N. A., and huyghenian oculars 2 and 4. Complete in mahogany case... 10.0.0... cece cece ence eet eeeneeaee 261.00 6895. ditto, but with apochromatic outfit consisting of dry apochromatic objectives of 16.2 mm and 4.3 mm, and 2 mm homo-immersion objective of 1.30 N. A., with compensating oculars 6 and 12. Complete AMET AMO PAT YACASCe fete cece cot ex geen ea tn fash cater ease eo ok mo cet A ge Mattes cite ces oe ete ASIA eel Pccnesne Ua eas Se 353.50 Note—The above outfits comprise the minimum equipment of objectives and oculars recommended for purchase with these microscopes. These selections of objectives and oculars in either the apochromatic or achromatic series, are usually included in all outfits, so that for more elaborate outfits it is only necessary to add to the above prices those for the addi- tional objectives or oculars required. 404 \W ; a AN wi ee a MM Wie 6899 MICROSCOPE, ZEISS STAND I. This instrument is recommended for the most refined investigations by ocular observation, micro-photography and micro-projection. The large body tube permits the use of projection objectives and micro-planars, with full utilization of the emergent beam. We stock this Stand na two Bee apeneencns as follows: Stand IA with plain, vulcanite revolving and centering stage. This stage is interchangeable wi revolving mechanical stage listed with Stand IB, and both are listed Sopanersly for purchase ae eee ment. For much laboratory work this large revolving plain stage is more convenient than any mechanical stage. Stand IB. This Stand is provided with large revolving mechanical stage in place of the plain vulcanite stage, with which it is interchangeable. This stage has a range of motion of 50 mm in one direction and 35 mm in the other, with a third scale and vernier showing the position of the movable stop for the object slide. Both Stands are furnished with complete Abbe illuminating apparatus with condenser of 1.40 N. A. These condensers are so mounted that the two front lenses can be removed, permitting the remaining lens to serve as a long focus condenser of small aperture for use with objectives of low power. When these condensers are used up to their full aperture with objectives of wide angle, the space between the condenser and object slide should be filled with immersion oil. Where outfits other than those listed are desired the total cost is to be had by adding the prices of the selected accessories to the prices given below for the Stand only. Stand IA, with plain vulcanite revolving and centering stage and complete Abbe illuminating 6896. Microscope, ; : apparatus with condenser of 1.40 N. A., but without nosepiece, objectives or oculars. In mahogany 153.00 gC eter ae Ure ater Sgn tery Nie nce nea mee Mey een aren ye cee eR none but with triple revolving nosepiece and apochromatic outfit consisting of dry apochromatic 2mm and 4.3 mm, and 2 mm homo-immersion objective of 1.30 N. A., with compensating oculars 6 and 12. Complete in mahogany case.......... 0.0.00. 346.50 6898. Microscope, Stand IB, with large revolving mechanical stand and complete Abbe illuminating apparatus with condenser of 1.40 N. A., but without nosepiece, objectives or oculars. In mahogany case 186.00 6899. ditto, but with triple revolving noseplece and apochromatic outfit consisting of dry apochromatic objectives of 16.2 mm and 4.3 mm, and 2 mm homo-immersion objective of 1.30 N. A., with compen- sating oculars 6 and 12. Complete in mahogany case............00.. 000s 379.50 Note—The above outfits comprise the minimum equipment of objectives and oculars recommended for purchase with these microscopes. This selection of objectives and oculars, in either the apochromatic or achromatic series, is usually included in all outfits, so that for more elaborate outfits it is only necessary to add to the above prices those for the additional objectives or oculars required. 6897. ditto, objectives of 16. 405 MICROSCOPE, ZEISS STAND IPhC FOR MICRO-PHOTOGRAPHY. This is a recent modification of Stand I designed especially for use in micro-photography and micro-projection. It is provided with a large body tube, which permits the use of projection objectives and micro-planars with full utilization of the emergent beam, and with special micro-photographic stage which differs from the large revolving mechanical stage listed with Stands IB and IIIE in that it imparts an exceedingly slow motion to the object. On this account the total range of displacement is only 10 mm in two directions at right angles to one another with the displacement reading by two scales and verniers. This stage is not fitted with centering device, and is not interchangeable with either the large revolving mechanical stage or plain vulcanite revolving stage, as supplied with Stands I and III. We stock this stand with the complete Abbe illuminating apparatus with aplanatic condenser of 1.40 N. A., which has been found more satisfactory for photographic and projection work than the Abbe condenser regularly supplied with Stands I and ITI. In this condenser the front lens can also be removed when desired to use the rear lens as a condenser of narrow angle with low power objectives. 6910. Microscope, Stand IPhC, with large revolving micro-photographie stage, complete Abbe illuminating ap- paratus with aplanatic condenser of 1.40 N. A., as above illustrated and described, but without nosepiece, objectives or oculars. Sins Mahogany: cases soei5 esta aus slesdnnse ices Aon uptanases 207.00 6911. ditto, but with quadruple revolving noseplece, dry apochromatic objectives of 16 mm, 8mm and 4 mm focus, 2 mm homo-immersion objective of 1.30 N. A., compensating oculars 2, 4, 8, 12and 18, and micrometer ocular K-6. Range of magnifications 31 to 1800 diameters. Complete in mahogany case 474.50 6920. Plain Revolving Vulcanite Stage, interchangeable with large revolving mechanical stage on Stands I 1 ePID Nd Raabecos neck ccs eh see A heen one AN) ha anaes he weaer Sates Ci ener ena yd aes CSIRO oes 1.00 6921. Large Revolving Mechanical Stage, with.centering Blass: cece ns eee a ne oa eee ..... 44.00 6922. Center Housing, for attaching either of above Stages to Stand IIICA, but not required for Stand IIIE, IA GE soles kg geese Bae Eee SFI ea ating ere sen A Saran Aci Sh ee Ryd eoaede cee ane Sedan cas 7.50 6923. Paraboloid Condenser, for dark field illumination. This condenser is interchangeable with the Abbe con- denser of 1.40 N. A., regularly furnished with Stands Tand III......................... 20.00 6924. ditto: without, diaphragm oA! eccu fr ox spe tanhe aes br ona le Saas aac Pipa hia, ca ine 16.00 6925. Paraboloid Stops, for Zeiss objectives of over 0.8 N. A., when used for dark field ork. These are fur- nished without charge when paraboloid condenser and objective are ordered at the same time, but when ordered separately for any given objective are furnished at.................... ; 45 6790. Cardioid Condenser, for ultra-microscope; interchangeable with the Abbe condenser of 1.40 N. A. regu- larly furnished with Stands I and III. For more detailed discussion see page 398........ 20.00 6927. Triple Revolving Nosepiece..... 2.2.0... 0 020 c eect e tte tet t eens _ 11.00 6928. Quadruple Revolving Nosepiece.... ............. a ee an Plts id eer rch dor adh wet une mere mS 1) A R T H UR H. T H O M AS Cc O M P A N_ Y _ ZEISS HUYGHENIAN AND ORTHOSCOPIC OCULARS AND ACHROMATIC OBJECTIVES. Huy- ghenian or Orthoscopic Oculars should never be used with Apochromatic Objectives, as they are computed only for use In connection with the achromatic systems. The compensating oculars, on the other hand, may be satisfactorily used with achromatic objectives of considerable aperture, i. e., 0.85 N. A. and upwards, or, in other words, with Achromatic Objectives F and 1/12th inch homo-immersion. The two new Orthoscopic Oculars are recommended for use with Achromatic Objectives where high magnification with large field of view is required. As in the case of Compensating Oculars they permit the use of the eye at a very comfortable distance above the eye lens with the entire field in view. 4 We emphasize the new Achromatic 1/7th inch homo-immersion Objective not included in the pre-war Zeiss series. Many examinations are nowadays made without the use of cover glass, particularly in bacterio- logical and blood examinations, for which purpose we predict a wide usefulness for this Objective. 6930. Huyghenian Ocular, Zeiss, No.1,50 mme.f., 4X... at een ee F 3 2.50 6931. is < pe “2,40mm ‘“ 5X.. é eres 2.50 6932. ee nS “ 3,30mm “ 7X. 385 ; ‘ oe 2.50 6933. . - “~~ 4,25mm “ 10X. : ; i me 2.50 6934. “ » n “5,20mm “ 15X. ; : Sse 2.50 6936. Orthoscopic Ocular, Zeiss, No.6,15 mme.f.,20X............ .............. cape 5 5.75 6937. e ~ “7, 9mm “ 380X... i pag ‘ 7.50 6940. Achromatic Objective, Zeiss, a,, dry series, 36 mme. f.. Cees coun 4 4.75 6941. So Fs ““a*, dry series, 25 mme.f......... eee : 16.00 6942. ne cc “aa, dry series, 23.5 mm e.f., 0.17 N. A. ‘ : 11.00 6943. "3 os “A, dry series, 18 mm e.f., 0.20 N. A. . Rare 5 8.00 6944, te a “ _D, dry series, 4.4 mme.f., 0.65 N. A....... Ra eae ee a 15.00 6945. cr i “DD dry series, with correction collar, 4.4 mm e.f., 0.85 N. A... 29.00 6948. se rs ““ 1/7 inch homo-immersion, 3.5 mm e.f., 0.90 N.A........ . 25.00 6949. = is “1/12 inch Fluorite homo-immersion, 1.8 mm e.f., 1.30 N. A. 62.00 Table of Magnifications with Zeiss Achromatic Objectives and Huyghenian and Orthoscopic Oculars at 160 mm tube length and calculated for an image distance of 250 mm. Huyghenian Oculars Orthoscopic Oculars | | Objectives | a | | 1 2 3 4 5 6 7 | | a, 12 15 21 30 45 60 90 a* 3-8 5-12 8-18 10-22 15-31 20-40 32-63 | a 24 30 42 60 90 120 180 A 32 40 56 80 120 160 240 | D 160 200 280 400 600 800 1200 DD | 160 200 280 400 600 800 1200 1-7 || 200 250 350 500 750 1000 1500 1-12 ‘| 400 500 700 1000 1500 2000 3000 ZEISS COMPENSATING OCULARS AND APOCHROMATIC OBJECTIVES. The excellence of the Zeiss Compensating Oculars and Apochromatic Objectives needs no emphasis in this place. It should be re- membered that Apochromatic Objectives must be used with Compensating Oculars for satisfactory results, but that Compensating Oculars on the other hand can be satisfactorily used with Achromatic Objectives of con- siderable aperture, i.e., from 0.85 N.A. The two new homogeneous apochromatic objectives No. 6964 and No. 6965 are designed primarily for dark-field work. They produce a perfectly black field and at the same time are more convenient to use than the high power dry lenses because of freedom from sensitivity to fluctuation in cover glass thickness and perfection of cover glass surface. They also have greater working distance, and do not have to be provided with a special stop to diminish the aperture as do the wider angle homogeneous immersion ob- jectives. They are also valuable for bright-field work; being highly corrected, the image is of outstanding crisp- ness, and the low aperture results in a great depth of focus. 6950. Compensating Ocular, Zeiss, No. 2,83mm e.f., 3X.... Rule eye ea ae Name ee 6.25 6951. ss i “« 4,50mm “ 5X.... Ree Ve eae eaten 16:25 6952. “ &s ee “6, 35 mm EK ees oe chai Red was ees eer : 6.25 6953. “ Ke Ee Boom, LOX cea caaes nama re seer are 8.25 6954. «“ “ ei Aba 167 gam“ P6X aes iene eee ieee “Ae 6955. « i 78, 12-5: 20K vee PER Recgtenaa te eaoe erectile : 7.50 AG Ree 0 = eh > uO H. THO” M.A S Cc O M P A N Y 6957. Apochromatic Objective, Zeiss, dry series, 16.2 mme.f., 0.30 N.A.......................... 31.00 6958. 7 ie s poe Te 8 23nmcesfis (Os6 5) Ni Als: m2 a ae Agee Mea eecnaien, 44200 6959. Se oe ~ ess 4.3 mm e.f., 0.95 N. A Un ach ere eee ene eee! 53.00 6960. y we ee ce ue 2:9 nin Cf... O95 SNAG: cc me cao ee ca ew oie ee Hoe 63.00 6961. iG ns ne SS OM Ota. AON GA kn s ponds ee Bee eee eae wes 125.00 6962. ie “_homo-immersion, 2 mme.f., 1.30 N.A.... 0.0 ..0..0..00000004 84.00 6963. i iG “ . AB minvied.,. V80NG Ave ji parse cS ede daecdies 103.00 6964. @ a oe or Me 9:2 mm:6.t.;- 0:85 NA. oe eae tae eeee see. +5300 6965. as fs 2 “ i Bmanef.00.85. NAc. cox iach mee seeiaes 53.00 Table of Magnifications with Zeiss Apochromatic Objectives and Compensating Oculars at 160 mm tube length and calculated for an image distance of 250 mm. Focus of the Objective, mm | Seeker | Compensating Oculars | 3 | 5 7 10 | 15 20 | 16.2 30 50 | 70 100 150 200 8.3 60 100 140 200 300 400 | 4.3 120 200 280 400 600 800 2.9 180 300 420 600 900 1200 | 2 270 450 630 900 1350 1800 1.5 360 600 1200 | 1800 2400 | 840 ao hey ae at EN \\ \\ \ \ a yy ey fe \ WO 6966 ULTRA-MICROSCOPE OUTFIT, with Siedentopf Cardioid Condenser, Zeiss. As a complete outfit utilizing the Cardioid Condenser No. 6790 described on page 398, we recommend the following: No. 6968 Zeiss Stand III, without usual condenser, iris diaphragm or diaphragm carrier, but with simplified movable stage, cardioid condenser, centering adapter for the tube, 1-12th inch homo-immersion fluorite objective, specially cor- rected for 0.4 mm cover glass, compensating eyepiece No. 18 and Hyughenian eyepiece No. 1; No. 6791 Object Slide, chamber form, of rock-crystal; No. 6792 Holder for object slide; No. 6793 Cover Glass 0.4 mm thick; glass cell on wooden block (No. 9160 is also suitable for this purpose); and No. 7006 hand regulating are lamp, with 100 pairs of carbons. 6966. Ultra-Microscope Outfit, complete as above described and as shown in above illustration, with are lamp POLE LO VOCS: erik ara oo ect ne tepn Merah tat 2a 8 oe CURA RENE, See By iy me By ic oe een Neve a 253.70 6967. ditto; ‘with-are lampcior 220i volitss.02 u's 2 nis ied anh ie Ske hed hi fo deatatersrenc, henealy pene elloed aot aeals 256.95 6968. Ultra-Microscope, only, as supplied in above outfit, consisting of Zeiss Stand III without the usual con- denser, iris diaphragm or diaphragm carrier, but with simplified movable stage, cardioid con- denser, centering adapter for the tube, 1-12th inch homo-immersion fluorite objective specially corrected for 0.4 mm cover glass, compensating eyepiece No. 18 and Huyghenian eyepiece No. 1, IM CASC ses amare Data Mansel eaah aS Actas SINS Zeta eae ENEMA tHe IRA Seely eared Ale MEU atc BY entrap get idee 189.00 Nore—The Slit Type Ultra-Microscope, Siedentopf and Zsigmondy, is not carried in stock, but is supplied on special order. 408 6970 MICRO LAMP, 6-VOLT, 24-WATT, Bausch & Lomb, consisting of a gas-filled Mazda lamp with con- centrated filament, which closely approaches the ideal point source of light. The bulb is adjustable with reference to the condenser and the housing can be set at any point along the horizontal or vertical rods, or tilted. This lamp is furnished with a spherical bi-convex condensing lens, with which very satisfactory results are obtained, and as alternative equipment with an aspheric condenser in place of the spherical bi-convex lens. The aspheric condenser is corrected for spherical aberration by grinding to non-spherical curves, and the focus is such that a 60° cone of light is collected, permitting the full aperture of the substage condenser to be used. This form of condenser adds considerably to the price, but is recommended for the most satisfactory work. This lamp will be found satisfactory for all kinds of microscopic illumination, and is particularly recom- mended for dark field illumination, for which work its efficiency is further increased by the use of No. 6814 Auxiliary Condenser, which renders the beam parallel before it is reflected by the microscope mirror into the back lens of the dark field illuminator. Diagram below shows the approximate relative position of these illuminating units with which to secure sharp definition in dark field illumination. In this arrangement the lamp filament is distant from the micro- scope mirror about 30 inches and it is, of course, directed to line up with the mirror. The auxiliary condenser is set up about 8 inches from the mirror, intercepting the beam of light. The next step is to focus the filament by means of the sliding bulb support so that an image of the filament is formed upon the condenser back. There will then emerge from the condenser a parallel beam of light about 32-inch diameter and the final adjustment of the mirror is then made, preliminary to centering the dark field illuminator. Directions for manipulation of the dark field illuminator will be found in the booklet ‘‘Use and Care of the Microscope,” copy of which is sent upon request. As the Mazda lamp requires only 6 volts, a transformer or resistance must be used when it is connected with ordinary lighting circuits of 110 or 220 volts. On a.c. circuits, the small transformer is the most economical and convenient method of reducing the voltage, while on d.c. circuits the usual resistance is used. 6970. Micro Lamp, 6-Volt, 24-Watt, B. & L., as above described, with spherical condenser, cord and plug for lamp socket, and transformer for 110-volt a.c. circuit............0..00 00000 23.75 6971. ditto, but with transformer for 220-volt a.c. circuit................... Fe eee EE 23.50 6972. see“ resistance eo VR Qserte aia. is Fe Bie aeons Pherae Ne ee tee 24.50 6973. Sean ae es PDO ener oe a Rien Seat ie 27.75 6974. Micro Lamp, 6-Volt, 24-Watt, B. & L., as above described, but with aspheric condenser in place of the spherical bi-convex. With cord and plug for lamp socket, and transformer for 110-volt a.c. CINCUIbie aoe? ae ae Bee ke tes SNe cbs Pose ieNR se oat ae yh cw | Ottiy ee a me eee carer ain 35.50 6975. ditto, but with transformer for 220-volt.a.c. circuit... .. 0.2.0.6 cee ee eens 35.50 6976. eG te ’ -Fesistances. 1 WO ite Soo + ak Re Ra eee a at ie Wg vba pana sho eshte ANS 36.50 6977. ee: ee Se DD sS okt AT Wee cepa cts alin hy tee rand es fe ee boar rae cet cent 39.75 6560. Lamp Bulb, only, 6-volt, 24-watt, gas-filled Mazda bulb. ..............-0.. 0. . epee eee eee 1.25 6553. Transformer, for use with 6-volt, 24-watt, gas-filled Mazda lamp, on 110-volt a.c. circuit........ 7.50 6554. ditto,but fore22 0zvoltsases Cin CUlb ex .f6.s Sos wcdsneaacs a must nreiieasuial tiga satan satiex dee enaxh an Fae eee a Cito» MS 6555. Resistance, for use with 6-volt, 24-watt, gas-filled Mazda lamp, on 110-volt d.c. cireuit.......... 8.75 6556. ditto; but:for 220-volt-dves circuit: ¢ses5i cies esis eae Se ere ng Bee ond anyae dine. ... 12.50 Diagram showing Micro Lamp No. 6970 and Auxiliary Condenser No. 6814, in their relative position to the Microscope in order to secure sharp definition for dark field illumination, 6814. Auxiliary Condenser, for use in dark field illumination to secure most satisfactory results. The lens ; mounting carries both the convex condenser and blue glass filters, and the two clamping screws secure it at any desired height and at any vertical angle.....................02 0000000 5.75 409 A R T H UR H. T H O M A 5 C. - O° MJP A IN) LY 6980 6986 MICRO LAMP, 6-VOLT, 108-WATT, Bausch & Lomb. Thisis the new arrangement providing perhaps the most convenient all around laboratory micro lamp now available. The 6-volt, 108-watt lamp with concentrated filament gives a very intense light sufficient for dark field illumination, and is mounted in a large lamphouse on adjustable support. It is furnished with both double convex and aspheric condenser, and with and without Daylite glass. The lamp with aspheric condenser but without the Daylite glass is identical with that supplied with Micro Projection Outfit No. 7076. In the outfit with Daylite glass, one glass 55 x 55 mm, polished on both sides, is placed directly back of the condenser, while in the rear of the lamp box is mounted an additional glass 82 x 82 mm, yielding light of proper intensity for ordinary micro work. Because of the wattage of this lamp, it is recommended only for use with transformer on 110-volt, a.c. circuit. Transformer for 220-volt circuit can be supplied on special order, as can also suitable resistance for use on 110-volt d.c. circuit, in which latter use because of the direct pull of 18 amperes on the line, a circuit must be tapped having at least that capacity. For use in dark field illumination, the lamp should be used at a distance of about 15 inches from the front of the condenser to the mirror of the microscope. 6980. Micro Lamp, 6-Volt, 108-Watt, B. & L., as above described, with double convex condenser, and two Daylite glasses, one 55 x 55 mm behind the condenser and one 82 x 82 mm in rear of lamp. On adjustable support, with cord, plug and transformer for 110-volt a.c. circuit.....................-.. 43.50 6981. ditto, but without.:Daylite glasses: bc. awe was bee aol Mad oe ced a epee Gna dd poeeee en pues 38.00 6982. Micro Lamp, 6-Volt, 108-Watt, B. & L., as above described, with aspheric condenser, and two Daylite glasses, one 55 x 55 mm behind the condenser and one 82 x 82 mm in rear of lamp. On adjustable support, with cord, plug and transformer for 110-volt a.c. circuit....................0.-- 55.50 6983. Gitte bub: without -Daylitecelassess (ric comers wracl b os us lessens Gtk mapa cal Sorat sere aoe ae ooh aid tle anes eae ca 50.00 6984. Lamp Bulb, only, 6-volt, 108-watt, gas-filled Mazda bulb.............00.00.0.0. 00.00.0000. . 2.50 MICRO LAMP, SUBSTAGE FORM, Bausch & Lomb. A compact and efficient source of light for the microscope, in which the complete outfit is placed between the members of the microscope base and immediately beneath the substage with the microscope mirror pushed to one side. When desirable the lamp can be used equally satisfactorily in front of the microscope with the light reflecting from the mirror in its usual position. The illuminant is a 15-watt, 110-volt Mazda lamp mounted in metallic housing with double ventilated sides and top, and deep curved reflector fixed behind the lamp bulb to intensify the illumination. The lamp is oe supplied with one blue glass and one ground glass, and as alternative equipment with Corning Daylite glass (see Prof. S. H. Gage, Science, October 15, 1915, pp. 534-6) which gives when placed in front of the microscope lamp an almost pure white light, rendering true color values of stained specimens. 6986. Micro Lamp, Substage Form, as above described, with one each blue glass and ground glass, connecting cord and plug for 110-volt circuit . toy rant encna ivaeetites adhe oe cgs & thaws pagers sages, ach oe geen ean 6.00 6987. ditto, but with resistance for 220-volt GiRCLL eee en Aa Re re ea ne A . 10.25 6988. Micro Lamp, Substage Form, as above described, with Corning Daylite glass in place of the blue and ground glass; connecting cord and plug for 110-volt cireuit............0..0. 0000000000 ee 7.00 6989. ditto; ‘but.with resistance for-220=volt; Circuits) oe fh. sus cache nc ska. oot ka Gok b wunoulels sLaineees . 11.25 6990. Resistance, for use with 15-watt, 110-volt Mazda lamp, on 220-volt circuit................... . 4.25 6991. Lamp Bulb, only, 15-watt, 110-volt Mazda bulb. .... 0.0 ees 1.00 410 6992 MICRO LAMP, CHALET FORM, Bausch & Lomb. A new lamp in accordance with the specifications of Prof. S. H. Gage, see Science, October 15, 1915, pp. 534-6. The illuminant consists of a 100-watt 110-volt Mazda lamp in a light-tight housing, with projecting eaves to shade the eyes of the worker, and with either one or two windows equipped with Corning Daylite glass, giving an almost pure white light which brings out the true color value of stained specimens. The lamp bulb is adjustable for bringing the filament opposite the windows. The housing has no floor or bottom, and may, therefore, be placed over dishes for melting paraffine, etc. 6992. Micro Lamp, Chalet Form, as above described, with one Corning Daylite glass window; cord, switch and DlUgtOr LOZVOltCINCUIbs neues Hak ante ohne kills eat en od i eA yd he cme coh ah l 14.50 6993. ditto, but with resistance for use on 220-volt circuit................. ieee dent oie eS axe. 22:50 6994. Micro Lamp, Chalet Form, as above described, but double form, 7. e., with two Corning Daylite glass windows; cord, switch and plug for 110-volt circuit........0.0.0.000 00000002 c ee eee 16.50 6995. ditto, but with resistance for use on 220-volt circuit.........0.0000 0.0000 ee 24.50 3748. Resistance, only, for use with 100-watt, 110-volt Mazda lamp, on 220-volt circuit............... 8.00 3749. Lamp Bulb, only, 100-watt, 110-volt Mazda bulb........0.0 20.00.0000 ee 1.35 6996. Micro Lamp, Welsbach Gas Lamp, Bausch & Lomb, with burner of the inverted type enclosed in a ventilated housing measuring 34 inches each way and provided with a high-grade condenser 13 inches in diameter. In addition to the vertical adjustments, the lamphouse may be tilted and revolved about its own center. The compactness and adjustments are such that the condenser may be brought within 2 inches of the microscope mirror, if desired. Complete on stand, with mantle and condenser, but without gas tubing............. 0.0.0.0... 0c ee eee eee 11.50 6997. Welsbach Gas Mantle, Reflex, size four... 0.20... 0. eee eee ee .25 “7000 MICRO LAMPS, HAND FEED ARC. The arc lamp used on d.c. circuits remains the ideal source of light for microscope illumination for all purposes, including dark field illumination. With a little experience, the feeding of the carbons can be accomplished conveniently and many observations can be made between the feed intervals. Where d.c. is available, the crater of the positive carbon should be used as the point source of light. Where only a.c. is available, the advantages of the arc lamp as compared with the (Continued on following page.) 411 Ap GRO oF He Us —-R Hi hE Os 2M ASS. Cc O M P A N_ Y MICRO LAMPS, HAND FEED ARC _ (Continued) 6-volt, 24-watt, gas-filled Mazda lamp as used in Micro Lamp No. 6970, etc., are distinctly diminished, but even with a.c. the arc is preferred by many workers. _ Both the Bausch & Lomb and Spencer Micro Lamps are furnished with adjustable condenser and mounted on adjustable stand. In the Bausch & Lomb lamp the carbons are fed at right angles to each other and in the Spencer lamp at an angle of 60°. ; : a common with all are lamps used on incandescent lighting circuits, a resistance suited to the voltage is required. The lamps are regularly supplied with solid carbons of 4 mm and 5 mm diameter for use on d.c. circuits. On a.c. circuits, the best results are obtained by the use of 8 mm cored carbons for both poles and the lamps are so fitted out when a.c. is specified. 7000. Micro Lamp, Hand Feed Arc, Bausch & Lomb, as above described and illustrated. The carbons can be fed independently or simultaneously. With cord and plug for incandescent lamp socket, and resistance 4.5 amperes for 110 volts. . cao eee Senate aC ae een aati pean 32.25 7001. ditto, but with resistance for 220 volts : ; i ponies a Meas ee De SIO rola 36.00 7006 7002. Micro Lamp, Hand Feed Arc, Spencer, as above described and illustrated. With blue glass and ground glass in addition to condenser, connecting cord and plug for incandescent lamp socket, and resistance A-HcamMpPeres fOns OF VOICES: ae. ct cab pe aan bao cam os Pera Sent mB ce Gs. Se Sarahonenn ety. bane be uae eee aa aac eth et 32.25 7003. ditto, but with: resistance tor 220) VOltsy occ ci crac b.acklchd arid Lideausadtr Gages te Seat enema weed Aue heedehs 35.50 7004. ‘‘Daylite’’ Glass and Adapter, for Spencer Hand Feed Arc Lamps......................0.0.4-. 2.25 7006. Micro Lamp, Hand Feed Arc, Zeiss, with resistance for 110 volts..............0.0..0.0........ 33.75 7007. ditto, but with resistance for 220 volts...............200000 000 cece ee . 37.00 6557. Resistance, fixed form, 4.5 amperes, for use with any of above hand feed arc lamps on 110-volt circuit ie 15 6558. ditto, but for 220- volt OLN CUM Gee sired oan eae tenes teas as Seen en ae Be tne ane aay EA A yeep eS ek ome a 2.50 2852. Carbons, Cored, for use with hand feed arc lamp, when same is used on a.c.; ; 150 mm long x e mm Giameter: “Per Oy ic otc get ais Sar ata thas oa name Paterno NN cae ce prs DEN PRN oem .40 2853. ditto, but 150 mm long 3 xi6smm diameter. (Per WO. is a tamsgevan of cncrmtAn dps onan wane ante .40 2854. C arbons, Solid, for use with hand feed arc lamp, when same is used on d.c.; 150 mm long x 5mm diameter. PT UO soi aa cigs anes nc ee) il ia eA al a ITA Kaa ee REAR Are tar Ie By ale Seca nee pee -40 2855. ditto; but 150:mm-long:4 mmrdiameter. Per VO... 4 208s ceed ee eas el eae he .40 Parcels in our shipping room specially packed for parcel post export shipment. 412 MICRO COVER GLASSES AND SLIDES Le — <— Zam. som. 18mm NS Ue cede | meets ___anr.ca. 7020—(Actual size) 7020. Micro Cover Glasses, Squares, Non-Corrosive, Red Label, of hard crown glass of slightly greenish tint when viewed edgewise, guaranteed against corrosion in any climate. These are the only Cover Glasses we are willing to guarantee against corrosion under all conditions and should not be confused with lower priced glasses made of soft white glass. From the same source and of exactly the same quality as sold by us for the past twenty years. Neatly packed in } ounce round wooden boxes with conspicuous red label. Please specify size and thickness in ordering. DIZE SIN nee ete he een PAY ny a 12 15 18 22 25 No. 1 (from 0.13 to 0.17 mm thick), per ounce......._ 1.80 1.50 1.50 1.50 1.50 No. 2 (from 0.17 to 0.25 mm thick), perounce.......__1.50 1.10 1.10 1.10 1.10 10% discount in cartons containing 25 ounces=50 boxes. 20°% discount in cases containing 100 ounces=4 cartons =200 boxes. a / S x \ * Be Oe / x \ / 5 ‘ ese JS %% / \ : | deo ee a ; 29 | 25mm. ON \ 1 Sith | «wo MM. / \ ia Sees ( 12mm) 15mm. an \ pee 7 } y, / f Te ; = Z Nano” Sars oer AT COL Sel Aa es 7022 7022—(Actual size) 7022. Micro Cover Glasses, Circles, Non-Corrosive, Red Label, same quality as No. 7020. Packed in 4 ounce round wooden boxes. ‘Diameter mmc s ex. ioc, diss eeuseatenn beter as Stee ea ee ee ee eee ee 17.50 H MICRO-PHOTOGRAPHIC CAMERA, Bausch & Lomb. This camera is designed for medium power work in any laboratory and has long demonstrated its general efficiency and convenience for such purposes. The outfit consists of a heavy base 13 x 93 inches; adjustable plate 8 x 6 inches to carry microscope; graduated optical bed, 263 inches long, carrying camera parts; inclination joint permitting optical bed to be adjusted at any angle between horizontal and vertical. With adjustment of camera supports to align with microscopes of different dimensions. The two camera supporting frames are clamped to the optical bed and carry a bellows long enough to accommodate work at any distance along the bed. The first frame carries the front board with tube adapted for the microscope, or a shutter and this adapter. The rear frame carries a plateholder box with a hinged cover at the back and two springs, permitting the plateholder to be laid in place and then gently, but firmly, pressed into exact position. The focusing screen of ground glass with clear center slides into two grooves in the camera box. The microscope plate has a movement of 4} inches, permitting the microscope to be removed from the optical center for examining a slide and quickly replaced. The adjustments on the plate will accommodate any standard microscope. 7084. Micro-Photographic Camera, Model H, as above described, with camera parts to take 4 x 5 inch plates, but without shutter, or illuminating apparatus or microscope, as shown in illustration... .. 75.00 7085. ditto, but with camera parts to take 5x 7inch plates. Without shutter, or illuminating apparatus Or microscope;.as shown in ilustration j..c.5.2¢4hccsy Sheen cern Shc bez atonn s Aunts MEG armae ea die 80.00 6544. Automatic Shutter, with maximum opening of 40 mm, for use with instantaneous bulb or time exposure, ready; to-attach tovcamera :ssccec cfc toh Ot cued Gone oman pn ie au nneae & Samer mama aes wick 17.50 We list and sell many articles under the manufacturer’s name and, while these manufacturers are primarily responsible for the design and performance of their product, we take full responsibility— having exercised no little discrimination in our selection—for all such trade-marked or branded items in this catalogue. 418 Micro-Photographie Camera LDA, with arc lamp and rheostat, and with compound microscope in position for drawing. ; LD MICRO-PHOTOGRAPHIC CAMERA AND DRAWING OUTFIT, Bausch & Lomb. This apparatus is arranged so that it may be used for micro-photography with either an ordinary compound microscope, as shown in the illustration, in either a horizontal or vertical position, or with the special Photomicro Microscope No. 7100 in the horizontal position; also for drawing by directing the image on a horizontal drawing board by means of a reflecting mirror placed over the ocular. It is very rigidly constructed and will be found most satis- factory for general laboratory work. Where the outfit is to be set up for routine work, especially in drawing, such as reconstruction work, the use of Photomicro Microscope No. 7100 is particularly recommended. Supporting Stand—Of cast iron; feet of stand have lateral spread of 25 inches; base plate, carrying camera bed and optical bed for illuminating accessories and microscope plate, is 45 x 7 inches, and 39 inches from the floor. . : Illuminating System—Consists of a 5-ampere, 90° hand-feed arc lamp with rheostat, 6-volt Mazda lamp and transformer, or Pointolite lamp with special starting and controlling resistance; aspheric condenser in focusing mount; support for ray filter; one ground glass, one blue glass and one green glass filter. All of these parts are mounted on a support adjustable for height, and with micrometer adjustment for vertical and lateral adjustment. ; Microscope Plate—Attached to optical bed by means of clamps so that the microscope may be moved along the optical bed to bring it to the desired location, either for drawing or for connection with the camera. Camera—Optical bed 25 inches long, graduated to 60 cm with inclination joint; wooden frames, bellows, ground glass and one double plateholder for 5 x 7 inch plates; wooden frames attached to two supports on optical bed, upon which they are adjustable to bring center of camera into alignment with microscope; front board of camera fitted with automatic shutter and light-tight connector for microscope. d ina? Drawing Board—Of wood, neatly finished, 14 inches square; adjustable on front standard of supporting stand, which is graduated so that one can readily reset the board at any particular position; supplied with velvet hood on adjustable standard to shield board from light when desired. 7086. Micro-Photographic Camera LDA, as described above, for use with either ordinary compound microscope, as shown in illustration, or special Photomicro Microscope No. 7100, with arc lamp and resistance for: 1.1.0 volts, but without microscopes « 03.46 fa ce sce din ack enw toe eA Sone Gates hou WA 285.00 7087. ditto, but with resistance for 220 Volts: 0.0. ccc be oe ee ee eee 288.75 7088. Micro-Photographic Camera LDM, as de- scribed above, for use with either ordinary compound microscope, as shown in illus- tration, or special Photomicro Microscope No. 7100, with 6-volt Mazda lamp and transformer for 110-volt a.c., but without microscope.............. ... 275.00 7089. ditto, but with transformer for 220- VO iis wer she arise aa panned ence 278.75 7090. Micro-photographic Camera LDP, as de- scribed above, for use with either com- pound microscope, as shown in illustra- tion, or special Photomicro Microscope No. 7100; with Pointolite lamp and special starting and controlling resistance for d.c. only, either 110 or 220 volts, but without microscope............ 300.00 Micro-Photographic Camera LDA, with arc lamp and rheostat, and = with compound microscope arranged for micro-photography in 7086 i horizontal position. 419 7092 Micro-Photographic Camera GPVA, with are lamp and rheostat, showing camera on sup- plementary optical bed and compound micro- scope (not included in the price) in position for vertical micro-photography. GP MICRO-PHOTOGRAPHIC CAMERA, Bausch & Lomb. This camera is recommended to those who wish an apparatus of unusual rigidity and mechanical accuracy, particularly where high magnifications are to be undertaken. The support for the microscope is adjustable for height, so that any standard type of microscope may be used and brought into alignment with the center of the camera parts, and the microscope plate may be turned 90° to enable one to conveniently look directly into the microscope for searching the field to be photographed. By means of the supplementary optical bed carrying the camera parts, the camera may be used in either a horizontal or vertical position. Such an arrangement is often desirable for photographing gross objects. When the equipment is fitted with the supplementary vertical bed the rear frame of the camera is fitted with a door on the side so that the image may be focused through this open door when the camera is used vertically. Supporting Stand—Of cast iron, massive construction, having base of four feet cast in one piece with heavy connecting rib; base has spread of 54 x 24 inches, and feet are fitted with both casters and leveling screws; two upright supports carry optical bed at height of 42 inches from floor; optical bed, 78 inches long by 4}2 inches wide, is graduated in millimeters and centi- meters with every fifth centimeter numbered; wooden shelf for accessories, measuring 37 x 18 inches, is mounted between upright supports. Illuminating System—Consists of 5-ampere, 90° hand-feed arc lamp with rheostat for 110 volts, 6-volt Mazda lamp and trans- former for 110 volts, or Pointolite lamp with special starting and controlling resistance; aspheric condenser in focusing mount; support for ray filter; one ground glass, one blue glass and one green glass filter. All of these parts are mounted on a support adjustable for height, with micrometer adjustment for vertical and lateral adjustment and with extension rod for adjusting arc from rear of camera. Camera—Consists of supports carrying tapering bellows with draw of approximately 50 inches, having wire supports in center; rear support carries box of neatly finished hard wood, with reversible adapter carrying laboratory plateholder for 8 x 10 inch plates and kits for smaller sizes, also with two focusing screens, one ground glass with clear center and one clear glass with graduated cross lines in center; hinged cover with two springs at rear of adapter permits plateholder to be placed easily in exact position without jarring apparatus; plateholder of special book form construction, insuring exact registration; automatic shutter, No. 6544, with steel leaves, having a maximum opening of 40 mm; may be set for instantaneous bulb or time exposure; supplied with tube for making light-tight connection with microscope eyepiece. Microscope Plate—Of metal, 734 x 5'4 inches, provided with three leveling screws to serve in bringing any microscope into exact alignment with optical axis of camera; fitted to main optical bed by clamping block and provided with vertical screw of 9-inch range, operated by hand wheel, for accommodation of varying center distances on different microscopes; so con- structed that plate may be turned out 90° for locating field to be photographed by direct observation, and provided with a stop which brings it at once into alignment with optical axis of camera when turned back; support attached to plate carries universal joint and pulley with extension rod, by means of which fine adjustment of microscope, whether lever, prism or side adjustment, can be controlled from rear of camera box. While an ordinary microscope, as shown in the illustration, can be conveniently used with this camera, we recommend where it is to be set up as a permanent installation for routine work the use of Photomicro Micro- scope No. 7100. 7092. Micro-Photographic Camera GPVA, as described above, for use with either ordinary compound micro- scope, as shown in illustration, or special Photomicro Microscope No. 7100, with supplementary optical bed permitting use of camera in either horizontal or vertical position, with are lamp and resistance for 110 volts, but without microscope... ........0...0. 0000 c cee 519.00 7093. ditto, but with resistance for 220 volts. 420 7094 Micro-Photographic Camera GPVM, with 6-volt Mazda lamp and transformer, showing camera on supplementary optical bed and compound microscope (not included in the price) in position for horizontal micro-photography. 7094. Micro-Photographic Camera GPYM, as described on preceding page, for use with either ordinary com- pound microscope, as shown in illustration, or special Photomicro Microscope No. 7100, with supplementary optical bed permitting the use of camera in either horizontal or vertical position, with 6-volt Mazda lamp and transformer for 110-volt a.c., but without microscope...... 509.00 7095. ditto, but with transformer for 220-volt/a.¢...0. 5c. ees ea ke hada ee Lee ew cae hbew es 512.75 7096. Micro-Photographic Camera GPVP, as described on preceding page, for use with either ordinary com- pound microscope, as shown in above illustration, or special Photomicro Microscope No. 7100, with supplementary optical bed permitting the use of camera in either horizontal or vertical position; with Pointolite lamp and special starting and controlling resistance for d.c. only, either 110 or 220: Volts, but withoutsmiCroscope. 2 sci deeccae waa oak ie ian eiee OA Aes occas ae acoale kes 539.00 MACRO-PHOTOGRAPHY. The Type G Camera can be conveniently adapted to macro-photography of large specimens by use of the attachments listed below and shown in illustration on page 374. Where it is not desirable to illuminate the object by oblique illumination to be had by tilting the illuminant as shown in the illus- tration, vertical illumination is secured by use of the clear glass reflector, which is attached to the end of the Micro-Tessar Lens. 6530. Cone Shape Adapter, with 14-inch square right angle prism for attachment to the front board of Type Gi Gamera anes Abeer cai evsum ees Ree iat eearmen cre eee Sectpeie RTA a Faeyr 50.00 6531. Specimen Table, for attachment to the optical bed of the Type G Camera, with hand wheel and worm screw for raising and lowering the specimen for FOCUSING cre ete 2 ce fa elegans syed Seats cant hil son A 45.00 6532. Clear Glass Reflector, for attachment to end of Micro-Tessar Lens for vertical illumination instead of oblique . . Be eta bara Paes reg at of nae taste tea apart tains SHAAN ad rer net YR 7.50 6545. Double Plate Holder, for 3} x 4} inch plates, without reducing kits........................... 1.75 6546. ditto, for 4 x 5 inch plates, without reducing kits...... 20... 6... een 1.75 6547. “but with reducing kits for 3! x 41 inch plates... 00... eee 2.25 6548. Double Plate Holder, for 5 x 7 inch plates, without reducing kits......................0...... 2.00 6549. ditto, but with reducing kits for 3} x 44 and 4.x 5 inch plates........0.....000............. 3.20 6550. Double Plate Holder, for 8 x 10 inch plates, without reducing kits..........0...00...0....0... 2.75 6551. ditto, but with reducing kits for 5x 7, 4x5 and 3; x 44 inch plates. ..... oo. 4.85 Special Single Laboratory Plate Holder, book form, for 8 x 10 inch plates, with reducing kits for any size of negative from:37:x 42 Up to:8 x10 mechs. oo scot aa name Mande en eae oa Ges de Bea E 7.00 421 6552. 7100 7100 Photomicro Microscope with Reversing Mirror No. 7101 Photomicro Microscope, shown with projection ocular and with Micro-Tessar and large condenser in posi- as used in micro-photography. tion for drawing, reconstruction modeling, etc. PHOTOMICRO MICROSCOPE, Bausch & Lomb. This microscope was specially designed for use with Micro-Photographic Cameras LD and GP and combines great rigidity, when clamped on bed plate, with sim- plicity of adjustment where routine micro-photography or drawing is to be conducted. It is provided with large body tube and with large substage condenser so that the full value of the three Micro-Tessars can be utilized when these objectives are used for low power reproductions without the use of an ocular. The projection oculars are recommended for use with this instrument for both micro-photography and projection with objectives of 16 mm and all hizher powers. When the high power objectives are used with projection ocular, the medium and high power condensers are fixed in a centering mount in the substage in place of the large diameter condenser as used with the Tessars. For drawing in connection with the LD outfit the reversing mirror is necessary, and this microscope is particularly recommended for use in connection with the LD outfit for reconstruction modeling as used with the Micro-Tessars and large substage condenser without oculars. 7100. Microscope, Photomicro, as above described, with large diameter condenser, for use with Micro-Tessars, and with aplanatic condenser, 1.40 N. A., in centering mount for use with the medium and high power objectives, and projection ocular, but without micro objectives or Micro-Tessars, or re- Versing Mirror Lor drawin Ge os de sans encks ae Stace Gee iee PHS ee era es ae ee A 174.00 7101. Reversing Mirror, for drawing, as shown in illustration, with collar for attaching to Photomicro Micro- SC ODO rons afte b Bumie ea an ori de ak Ma enlsh coneet aueennlen ts are cits mares ch em nea bay ee dd Yael toa bee Rania apaeerA a 18.00 7102. Projection Ocular, of achromatic construction; superior for both micro-photography and projection to the the ordinary huyghenian ocular; 3X...................... DE aha Ali tnoe tala Ponty ts Foci ys 9.00 7103. ditto, but 5X... Wa Meta d se Dein ae ee LE te Te ne ee Ee ee 9.00 7112 7114, 7115 MICRO-TESSAR OBJECTIVES, Bausch & Lomb. These are constructed after the formulae of the famous photographic objectives of the same name and are widely used in micro-photography where large areas are to be photographed at low magnification and without the use of an ocular. The angle of view is 55°. The illumination is uniform and the definition remarkably sharp. They have been found particularly valuable in the photography of certain kinds of sections in embryology and histology of the nervous system. The 72-mm e.f. Tessar is furnished in a regular photographic mount while the 48 and 32-mm are provided with society screw and, therefore, can be used on the nosepiece of an ordinary microscope. These Tessars are widely used with photomicro microscope above described and with the type LD micro- photographic camera. 7110. | Micro-Tessar Objective, as above described, mounted with metal iris diaphragm; 72 mm equivalent focus, in regular photographic lens style mount...........0..0..00..0..0..0..00 0-00-00 - eee 44.00 7111. ditto, but 48 mm equivalent focus, and provided with society screw........................ 36.00 7112. ditto, but 32 mm equivalent focus, and provided with society screw........................ 36.00 Focusing Glass. In all micro-photography a focusing glass is a very convenient accessory for securing a sharp definition and the two listed below are recommended. TAs. ““Doublet Pocusing Glass: ele eich tec aca: Bytes Res dela de 3 ity ecko dene eased see Maan tete take Ue hbo 5.00 7115... -Achromatie- Focusing Glasses kaki 2 oie stv sed oe Gave es 8 oxen Gye eA Aa ds Ba te as aes 10.00 A R T H U R H. T H O M AS C O M P A N Y RAY FILTERS, Wratten & Wainright “M”, specially selected for photomicrography, and described in booklets, “‘ Photomicrography” and ‘Wratten Light Filters,” published by Eastman Kodak Co. The filters are two inches square, cemented in “‘C” glass, a white optical glass of imperfect figure, suitable for visual work or such ais es pioomrorper any, where the filter is placed in the path of a dispersed beam. The set consists of nine ters as follows: Number Name_ Color Remarks | Number Name _ Color Remarks 25 A Orange (Tricolor Red) Contrast | 29 F Orange (Tricolor Red) Contrast 68 B Green sf | 15 G Yellow ss 49 C Blue “ fs 45 H Blue (Blue Green) Vie 35 D Magenta and Violet a 6 K-l Yellow Orthochromatice 22 E Orange re 7116. Ray Filters, as described above. Per set of nine, in leather case..............-.. cece e cece ee 14.00 7117. Photographic Plates, Wratten & Wainright ‘‘M’’. These plates are medium speed panchromatic, giving great density and contrast. Their use in photomicrography is described in a booklet, ‘‘ Photo- micrography,”’ published by Eastman Kodak Co., in which the multiplying factors of the filters are given. These plates must be handled and developed in absolute darkness, or by the light of a Wratten Safe Light Lamp, using a Special Green Safe Light, Series 3, to be had of photographic dealers. Size-of plates; inches... 5 ose Ganee eee Sanaa 31x 41 4x5 5x7 8x 10 Per dozens. nc a ior aed ee poety pln tt eo .80 1.10 1.80 4.00 7120 7128 CLINICAL MICROTOMES, Bausch & Lomb, a newly designed series of microtomes taking the place of several models of the older series such as Student’s and Clinical or Physician’s Microtomes. A new form body casting for rigid clamping on the table is the basis for all of these instruments. ; ; No. 7148 Object Clamp for paraffine or celloidin sections and No. 7149 CO. Freezing Attachment with regulating valve for frozen sections can be used interchangeably on all of these microtomes; and the knife holder on all of them takes No. 7182 Knife, 90 mm blade. ; , ; In the Simplified Model, both the feeding mechanism and knife carriage are operated by hand. In the Medium Model the knife carriage is operated by hand but automatic feeding is provided. In the Automatic Model both feed and knife carriage are automatically operated by means ofa wheel drive similar in principle to that used on the Bausch & Lomb Rotary Microtomes. In this model a cam plate adjustable to various angles guides the knife carriage in an oblique direction, thus bringing the entire knife edge into action. These. Microtomes cut sections of 5 microns or more in steps of 5 microns, and in all three models the knife when in an oblique position cuts with the draw stroke movement so desirable in the cutting of frozen and celloidin sections. icrotome, Simplified Clinical, as above described; with Object Clamp but without knife... ...... 47.00 To Se but with No. 7183 Knife, 90 mm, with Handle and Honing Guide Bare IS cas oe 57.35 7122. Microtome, Simplified Clinical, as above described; with CO, Freezing Attachment in place of Object Clamp, but without knife............. genfe Macs oe Ge Seite A ee eee n rede iuiednaes pln 53.50 7123. ditto, but with No. 7183 Knife, 90 mm, with Handle and Honing (Gru Conia sheeted Ged Sav ucres 63.85 7124. Microtome, Simplified Clinical, complete outfit, consisting of Freezing Attachment, Object Clamp and Knife, 90 mm, with Handle and Honing Guide......................... 0.00000 70.85 i me, Medium Clinical, as above described: with Object Clamp but without knife.......... 77.00 oes Se but with No. 7183 Knife, 90 mm, with Handle and Honing Guide........ Reareea ae me 87.35 7128. Microtome, Medium Clinical, as above described; with CO, Freezing Attachment in place of Object Clamp, but without knife............ Smee deiaiae Ce seal eae ag sents Seasons a Meare ete 83.50 7129. ditto, but with No. 7183 Knife, 90 mm, with Handle and Honing Guide............ Pisrionens 93.85 7130. Microtome, Medium Clinical, complete outfit, consisting of Freezing Attachment, Object clamp and " Knife, 90 mm, with Handle and Honing Guide.................... 0... e eee ee eae. 100.85 423 7132—Back view 7141 7132. eS Automatic Clinical, as described on preceding page; with Object Clamp, but without MGs ea tomdn ie aah ais eles ce. eal nara a ars meee haan nen hera users Zu meus tr OS! 87.00 7133. ditto, but with No. 7183 Knife, 90 mm, with Handle and Honing Guide............... . 97.35 7134. Microtome, Automatic Clinical, as above, with CO, Freezing Attachment in place of Object een but WIL OUG Kl Oi a io6 8p Pes entrada i merle bes tl whine ered A eal aac Dara mes idee ta ut Conc Wreat eaie Ow codec ene 93.50 7135. ditto, but with No. 7183 Knife, 90 mm, with Handle and Honing Guide.................... 103.85 7136. Microtome, Automatic Clinical, complete ‘outfit, consisting of Freezing Attachment, Object Clamp and Knife, 90 mm, with Handle and Honing Cane ates eee ee ay ..... 110.85 AUTOMATIC FREEZING MICROTOME, Spencer. An automatic microtome designed for the rapid and accurate cutting of sections frozen by CO2. Sections can be cut, stained and mounted in 13 minutes from the time the tissue is placed on the freezing plate. This microtome is also well adapted for celloidin sectioning with the use of the object clamp in place of the freezing attachment, but is not so well suited for paraffine work, although it can be used with that medium. The CO, Freezing Attachment is provided with a hard rubber, non-conducting plate between the corrugated surface to which the object is frozen and the rest of the apparatus, which prevents the conduction of heat from the other parts of the apparatus to the specimen, thus saving time and CO,. In operating this freezing attachment the valve at the bottom should first be closed and the valve at the cylinder slightly opened to admit the gas into the tube. Then by opening and closing the small valve at the chamber three or four times in quick succession, the tissue is frozen without any waste and without any incon- venience caused by the freezing up of the chamber or the connections. The object clamp supporting socket is raised or lowered by a vertical feed screw with fine micrometer thread having a crank at the bottom for independent movement. This screw is firmly held in double nut bearings which provide for taking up lost motion and for eliminating any wear that may occur. The object support is firmly held by a strong steel spiral spring down on the upper end of this screw. The automatic feed mechanism consists of an accurately cut ratchet wheel keyed to the vertical feed screw, in the teeth of which a hardened steel pawl engages. By means of a lever extending to the graduated scale shown on the front of the main frame base, this pawl may be thrown out of action by turning the index finger to the extreme left or it may be set to cut sections of any desired thickness. Each division of the graduated scale marks 5 microns. A drip pan shown in the illustration is intended for use with the object clamp, also shown, for celloidin sectioning. It is best to remove this drip pan when frozen sections are to be cut. 7138. Microtome, Automatic Freezing, as above described, with Freezing Attachment, but without knife or (OFS CE Clam Pierce sees eae eo ee oa tached tere eget ne MON a Lee eA Da tebe dee nye Monte oe hn 83.50 7139. ditto, but with Knife, 110 mm, with Handle and Honing Guide ......................... . 95.50 7140. Microtome, Automatic Freezing, as above described, but with Object Clamp in place of Freezing Attach- ment... “Wibbouts kiittels «ta own an eaate eae es eee akin nailcl's mek phe reads Oy aacn a a ake Meath ... 73.00 7141. ditto, but with Knife, 110 mm, with Handle and Honing Guide ............................ 85.00 7142. Microtome, Automatic Freezing, as above described, but with complete outfit pOnpintine of Object Clamp, CO, Freezing Attachment, Knife, 110 mm, Handle and Honing Guide. . ....... 98.50 7143. Object Clamp, only, for paraffine or celloidin SN aN ph ok hci ncey al nee ih Og ein tlhe dys A cot KEL e Lage ve 3.00 7144. Freezing Attachment, only, as described above, for COo........0.0. 0.000000 ee 13.50 7145. Microtome Knife, 110-mm blade, in case; for use with Spencer Freezing Microtome........ ... 8.00 7146. ditto, but with Handlé:and. Honing: Guides .s : occ ccccqgcn on ones caked boese A beens a Plast ae, a) at 12.00 7148 7149 7148. Object Clamp, only, for use with B. & L. Clinical Microtome, for paraffine work.................. 7.00 7149. Freezing Attachment, CO,, only, with regulating valve.........00.00.000 00000 c eee eee 13.50 CO, CYLINDERS, for use with Freezing Microtomes. (See illustration on page 327.) Of seamless steel, 54 x 51 inches. Each cylinder is tested, numbered and stamped with the wording required by Paragraph 1822a of the Interstate Commerce Commision regulations, which number is registered in New York with the Chief Inspector of the Bureau for the Safe Transportation of Explosives or other Dangerous Articles. Each cylinder contains 20 lbs. of CO, suitable for use in Freezing Microtomes and other laboratory purposes. These cylinders are returnable for credit at $9.00, all charges prepaid, only when they are stamped with our initials and test number and otherwise in accordance with the Interstate Commerce Commission regulations, which are frequently changed, and only when they have been used for containing CO». We do not undertake the refilling of customer’s cylinders, but ship from our own stock a filled cylinder, and credit, under condi- tions mentioned above, the returned cylinder. This procedure necessarily involves more expense than is incurred by the owner having his empty cylinder refilled at a local charging station such as are maintained in principal cities by the General Carbonie Company and The Liquid Carbonic Company. Our plan, as above described, has been found by experience to be the only practical method of control possible for us under all the circumstances of such transactions. Cylinders of CO, are preferably used in a vertical inverted position, so that all the liquid CO, is readily withdrawn. When used in a horizonital position, they should be slightly inclined toward the outlet for the same reason. These cylinders when containing CO. should not be stored or used near steam pipes, stove, or other source of heat greater than ordinarily room temperature, as the gas is liquified under enormous pressure which greatly increases by heating the cylinder. 5966. Cylinder of CO., as above described, containing 20 lbs. COz..............0.. 00.02 eee 26.10 5967. Iron Support, for CO, cylinders. Convenient for holding cylinder in inverted position, i.e., with valve LO Whos ie Sao rs ue tte tclsractte nays See meh eer agers cknk neal eras ea che a Ra ee Talia tN eras ONAN Sn G e 7.00 5968. Pair of Iron Supports, for supporting CO, cylinders in a horizontal position either on the wall, on top or underneath: the laboratory: tabley o)c..ayghoe sy ee kak ee ogee eee Deh oe Be ae anes 1.40 5969. Wrench, exactly fitting the hexagonal nut of the standard high-pressure cylinder No. 5966...... .85 Li i} 7150 7154 HAND MICROTOME, Bausch & Lomb. Designed primarily for free hand cutting of sections of stems and roots, but can also be used for animal tissues as well. The collar of the feeding mechanism is graduated in steps of 25 microns and the knife is passed over a polished glass plate through the center of which the object is clamped. Will take specimens up to 14 mm in diameter. Any section knife or razor can be used with this instrument. . Microtome, Hand, as above described, without knife orrazor...... bshice eticedea iv ee sebecnsart ener 10.00 viel, Section Razor, flat concave, with 75 mm blade. Suitable for use with the Hand Microtome...... 2.00 AUTOMATIC SLIDING MICROTOME, Bausch & Lomb. This is the most modern execution of the original sledge form of microtome. Itis alarge, rugged and substantial instrument providing a lateral adjustment of the feeding mechanism along the entire front of the stand, thus providing for different cutting angles and stroke lengths. The instrument feeds either automatically or by hand in steps of 2 microns with a range of 2 to 36 microns. A split nut provides ad release of the carriage at any point of feed and the resetting at any desired iti ed instantaneously. ave nee clamp engages Pee with the slide and accommodates objects 385x22mm. It is adjustable vertically and orientates in one plane and can be set at either side of the vertical slide for paraffine or celloidin sections. 7154. Microtome, Automatic Sliding, as above described, without knife......................200.. 115.00 7155. ditto, but with Shanked Knife, 165 mm.......... 00... eevee eee eee ...... 129.80 7188. Microtome Knife, only; shanked, 165 mm. In case............ 0.02.0 e cies e eee 14.80 425 7160 MINOT ROTARY MICROTOME, Bausch & Lomb. This is the original large model microtome designed by the late Dr. Chas. S. Minot, and improved from time to time under his supervision. It is recom- mended for making rapid serial sections in paraffine down to 1 micron in thickness. The feeding mechanism, protected by a metal guard, consists of a micrometer screw revolved by a large ratchet wheel. The amount of feed is controlled by a cam wheel which permits fine adjustment of the object in relation to the knife with the pawl disengaged and held off the wheel by a spring catch. The cam discis graduated in single microns numbered from 0 to 25, and the micrometer screw is fitted with a split nut and releasing lever by means of which the feed can be instantly brought to beginning, intermediate, or other position, and held. The object holder is in adjustable mounting, permitting orientation to any desired cutting angle. This microtome is designed and mostly used for paraffine sections, and while it can be used with special adjustable block for celloidin, its use for cutting in this medium is not recommended. 7156. Microtome, Minot Rotary, as above described, with three object discs but without knife....... 132.00 7157. ditto, but with No. 7183 Knife, 125 mm, Handle and Honing Guide..................... 144.80 7182. Microtome Knife, only, 125 mm, for Minot Rotary Microtome............................ 8.80 7183. ditto, but with Handle and Honing Guide. In case................... 000.0000 200002 ue 12.80 7158. Clamp, only, with plane post, for Minot Rotary Microtome, for use when paraffine specimen is embedded on block. Will take blocks up to 1 inch square.................. 0000000 cece eee 5.50 MINOT ROTARY MICROTOME, SIMPLIFIED MODEL, Bausch & Lomb. This instrument was also designed by the late Dr. Chas. S. Minot, to embody the convenience and efficiency of the original larger model ina simpler and less expensive execution. The general principles of the larger model are followed throughout, but the ratchet wheel is smaller diameter and provides only for sections from 2.5 microns to 25 microns in steps of 2.5 microns. This microtome is designed and mostly used for paraffine sections and while it can be used with special adjustable block for celloidin, its use for cutting in this medium is not recommended. 7160. Microtome, Minot Simplified Rotary, as above described, with three object discs, but without knife 82.50 7161. ditto, but with No. 7183 Knife, 90 mm, Handle and HoningGuide....................... 92.85 7182. Microtome Knife, only, 90 mm, for Minot Simplified Rotary Microtome...................... . 6.35 7183. ditto, but with Handle-and Honing Guide: .. 0b eck gh emcee Ba BR AEG s kee gene des 10.35 7162. Clamp, only, with ball post, for Minot Simplified Rotary Microtome, for use when paraffine specimen is embedded on block. Will take blocks up to 1 inch square............................ 6.00 ROTARY PRECISION MICROTOME, Spencer No. 820; with inclined plane feed which overcomes the inaccuracies usually encountered due to the up and down movement of the object. In this microtome the feed and movement are entirely independent. The sliding part which carries the object clamp (see SP, Fig. 1, page 427) is carried up and down by the block B, through which it is free to move backwards and forwards. It is, therefore, free from lost motion. The polished inclined plane surface at the end of this sliding part is held firmly against a projection P. It is a part of the very rigid feed mechanism which is independent of the up and down movement. The feed mechanism is composed of a rigid bearing, on which the feed block FB (of which the point P is a part) is moved by the feed screw F'S. As this block travels toward the side on which the balance wheel is located, the sliding part SP is forced forward towards the knife one half as much. The polished surface resting against the point P is set at the proper angle to accomplish this end. The screw is cut with two threads to the millimeter; it is revolved by a ratchet feed wheel with 250 teeth; each tooth represents, therefore, a move- ment forward of the object of one micron. The feed is so arranged that it can be set for sections of any thickness, from 1 micron to 60 microns, by turning the knurled button at the back of the case until the number representing the desired thickness appears opposite the indicator at the small opening in the side of the case near the balance wheel. 426 7166. Fig. 1 ROTARY PRECISION, MICROTOME, Spenc2r (Continued) The total excursion of the feed is 37 mm, allowing a sufficient range for cutting a complete series of a very large object without the necessity of a break due to resetting the knife and feed mechanism. The object clamp is a part of a ball which fits into its socket so uniquely that it is clamped as solidly as though it and its socket were one piece. The object is easily, accurately and delicately oriented to any desired angle. The angle can be changed in any plane without interfering with any angle already attained in another plane. The object may easily be rotated. The up and down stroke of the object clamp is 50 mm, which permits the cutting of very large sections and gives sufficient stroke for celloidin cutting. The clamp is held at its upper limit for orienting or trimming the block by pushing in the pin F. The knife is fastened by two clamps, each of which clamps the knife at the back and along 11 inches of the edge as well. It may be turned to any desired angle, and the clamps may also be moved toward one another to bring them as near to the ribbon as desired to gain additional rigidity. When the clamps are thus drawn together the knife may be moved so that practically all of the cutting edge can be used before the necessity of resharpening. The adjusting screws provide for knives of different widths. The whole knife support is adjustable to and from the object, and is very easily and conveniently clamped in any location, by a lever connected with an eccentric cam. The whole of the feeding mechanism is covered, protecting the wearing parts from dust and presenting avery neat appearance. The top of the case is hinged to the lower part, permitting it to be easily opened. The balance wheel is grooved, so that the instrument may be run by a motor. 7167 7166. Microtome, Precision Rotary, Spencer, as above described, without knife but with object discs.. 166.50 7167. ditto, but with Knife, Handle, Guide for honing, and three object discs ................... 180.00 7168. Microtome Knife, Plain, for use with Spencer Precision Rotary Microtome; 110 mm long, without Wari dlecstace ae ae nat amesetre onan py eomea sais Ome heh teed Aaah cau eemyi una pide euremate 9.50 7169. ditto, but with Handle and Honing Guide. In case. . rime GS:50 427 = 7170 MINOT PRECISION MICROTOME, Bausch & Lomb. This microtome, designed and improved under the supervision of the late Dr. Chas. S. Minot, is recommended as the best microtome available for the most precise work in either paraffine or celloidin, particularly in the cutting of large specimens. The knife is rigidly clamped to the rectangular frame in either oblique or horizontal position, while the object moves on the slide underneath. The feeding mechanism operates automatically and provides for cutting sections 1 micron up to 25 microns in steps of one micron. The available feeding length of the micrometer screw is 38 mm, and the screw is fitted with a split nut and releasing lever by means of which feeding can be instantly brought to begin- ning or any intermediate position and held. A rack and pinion device is provided for raising and lowering the object clamp, which is of rugged construction and takes specimens measuring 35 x 33 mm. It orientates in two planes, giving any desired cutting angle. The dimensions of the microtome are 40.5 cm long, 19.4 em wide, 24.5 em high. 7170. Microtome, Minot Precision, as above described, without knife................000.0.....0.. 275.00 7171. ditto, but with No. 7176 Minot Microtome Knife, 315 mm;in case ....................... 300.00 7172. Microtome, Minot Precision, as above described, but complete outfit consisting of No. 7176 Knife, 315 mm, No. 7174 Tilting Knife Clamps, No. 7175 Zabriskie Object Clamp, No. 7177 Glass Plate and Nop (18: Diamantine Powder msc 6 35 casey errno ih, oe ooeuags Sai hd Duman lah Guha Sane walt Berd Ss 339.50 UU wh UU - 7174. Tilting Knife Clamps, for Minot Precision Microtome. Per pair................. 00002000055 13.50 7175. Object Clamp, Zabriskie, designed to accommodate large objects on a Minot Precision Microtome. Takes Objects: measuring 1008 OMIM. ae eae Nestle nade 4 s1ktes eerste es wen Nie aa Sean cei 20.00 7176. Microtome Knife, Minot, designed specially for the Minot Precision Microtome. The handles are simply extensions of the back of which they are a part and have the same section, hence when the knife is placed in the clamps it is held perfectly true. The knife may be honed in the usual manner but, instead of stropping, the edge is polished by means of diamantine powder on a plane glass plate. The knife is 315 mm long, with a cutting edge of 190 mm. Incase...................-. 25.00 Wiis ‘Glass-Plate;:foruse im Sharpening. ..4.2. cs dene a taeda dee be nied daemon neh ondana lela seeltes 5.50 7178 —Diamantine: Powder) Per bottles. :,.5 5s sdsede sc ora coodlacerste ecclesia wea ny sole: sleepiness ease eaters 50 SFSPISIS IS TIS Is aa EE ‘Io 33 IS) ANAT CO. SL i 7184 7185 In position on knife 7188 7188 _ MICROTOME KNIVES. Our microtome knives are specially made for us under our direction in Phila- delphia, by workmen of long experience, They are forged, ground and tempered with exceeding care, and while some slight variation is to be expected as to relative hardness and thickness in different knives, they are all within the limits for satisfactory section cutting and sharpening. -Our method of grinding these knives provides that the cutting edge and the edge of the back lie in exactly the same plane, a very important feature in the longer knives when used obliquely as in celloidin sectioning, and also in sharpening. The plain knives, 7. e., without shank, for use in freezing and rotary microtomes, should always be honed and stropped with the use of attachable handle and honing guide, and where new knives are pur- chased we recommend that these attachments be purchased with the knife as listed, as the honing guides are fitted to each individual knife with which they are shipped and when ordered separately do not always fit the knife for which they are intended unless the knife is sent to us for adjustment. Most difficulties in satisfactory section cutting are due to the condition of the knife edge because of un- skilled attempts at sharpening. A microtome knife is usually considered to be unfit for use if it will not easily clip a human hair held by one end; and for many kinds of work even this is not a satisfactory guarantee of keen- ness. The cutting edge of a knife can also be easily examined under a low power on the microscope stage, and when it has been properly sharpened the edge will be seen to be smooth and even. 7182. Microtome Knives, Plain, for use with Freezing and Rotary Microtomes. With threaded hole in which to screw Handle No. 7184 for sharpening. Each knife is furnished in a suitable protecting case, but without handle or honing guide. engthvoriolade; Mimi h..0 5 joe cad. pce eed ea tas A eW ie eeeees 90 125 165 eS SCuthing Od Fes IMM 5 2 foc gre fs cena wat cae Sh MA a Sh apenas 82 120 158 PC Ne aise ce ce eon ere Ne Ph MAGMA elle Mra WY aia a trae taal 6.35 8.80 11.40 7183. ditto, but with Handle and Honing Guide, in case. Gength or blade; MIM.: . .c0-.a cork Micntiwersatnw net other aetneaw hn wgigiere @ iacgueee S 90 125 165 a ) = 4b - par lea BP one oe ye oe AE | ( A Be i Tomo ot [He he eo ee ee oot SAAN SNARE CANAL ESAT FLL is & ee OB Be et eee tet LACTOMETER HEADING _, xcibtstes= sian 7238 Slide Rule, Richmond, original form, for calculating the total solids in milk for specific gravity and per- centage of fat...... ee sige nie te aaee tetra athe tin ce omen 6.00 ditto, improved form, with the addition of several new scales providing for practically all of the calculations required in dairy chemistry. See Analyst, June 1920, 45, p.218, and Dairy Chemistry, 3rd ed., by H. Droop Richmond .........-. +000: see ee eeer eect nents eect e eee 15.00 fm 7240. 7242. 7246. 7247. al 7244 Balance, Torsion, for cream test; with sliding tare weight, weight pan, special bottle holder and arrest, sensitivity 8 milligrams; with special 9 and 18-gram weights. Finished in white enamel. HOT DO CULES wear sant memer hie POC etek menos try dSirca/ ik lonela ifthe ACA ea Oe eS 1 2 4 Ws ecticrhy lia a an ese ce Mer ecectan haar tena a alop mearetln PS te eC Ea spd Oe 30.00 31.00 34.00 Fat Extraction Tube, Rohrig, for use in the Rose-Gottlieb method; with hole in side of neck at top of tube 46 em high with a capacity to base of neck of 873 ml. The delivery tube is so placed that its center line coincides with the surface of 23 ml of liquid in the main tube. With polished wooden base with indentation for flask, but without flask as shown in illustration. As used in the Dairy Laboratory, Bureau of Chemistry of the U. S. Department of Agriculture....................000000- 3.50 ditto, but without hole in side of neck at top of tube...........0.0..0..0 000000 cece cece eee ee 3.10 Fat Extraction, Tube, Rohrig-Biesterfeld, for use in the modified Rose-Gottleib method, as described by Biesterfeld Evans, ““A Study of the Estimation of Fat in Condensed Milk and Milk Powders.” See Journal of Industrial and Engineering Chemistry, 9 : 12 (1917) 3.80 Sediment Tester, Wisconsin Type, for the determination of sediment in milk, filtering one pint of milk in a few seconds. The sediment is collected on a standard size cotton disc filter 1 inch diameter. Apparatus complete weighs about 2 lbs., and consists of metal cylinder with handle at side and air- tight top. Pressure on the bulb at the side forces the milk through filter. Complete with 500 COLCONSILGCTS astm sagt putty tae arte ne ee od DL GUN SESE cael race uet en boks eta tace es NaS oA eke 15.00 4316. Cryoscope, Hortvet, for the rapid and accurate freezing point determi- nation of samples of market milk. See Journal of Industrial and Engineering Chemistry, 13 : 3 (1921). Complete outfit including vacuum vessel, pair of special test tubes, metal stirrer, special top with metal tubes, rubber connecting tubes and bulbs, air drying tubes, funnel tube for pouring in ether, tube with side tube at bottom for removal of ether fumes, supporting stand, therometer reader, control thermometer, milk freezing-point ther- mometer, directions for use and bibliography of CES OSCODES: pa the detection of added water in milk.................. .00 4317. ditto, a simplified outfit consisting of the Cryoscope only, rubber bulb, funnel tube and two test tubes, but not including thermom- eters and other accessories listed above................. 30.00 4318. Thermometer, Cryoscope, graduated from + 1° to — 2° C, in 1/100° CIVISIONG eo) sha oh reac es hone erat ave ae eae Re ae eS 17.50 4319. ditto; the control thermometer for guarding against excessive super-cooling and the consequent too low convergence tempera- ture. Graduated from + 30° to — 30° C, in 1° divisions.. 6.00 434 CONTENTS RHOMBOHEDRAI vm ‘CUBIC SYSTEM Wy anand sa ant 11 AVUTUVE vita teteeatagaiis Lic MNEnHUIL A Gait ORTHORHOMBIC SYSTEM WV sven MMETRIC SYSTEM ‘Ah SMUT AMER ys Pe GNM MAME MSL FNL ane ANAL WANNATAN fan " tnt CONTENTS lieaer CUBIC SYSTEM © RHOMBOHEDRAL SYSTEM] He HH ty Qi) enema ta NTT ae ae vee om ti nny aT we mmm main wi |i eae ORTHORHOMBIC SYSTEM/} 4 i omit i ve mma nl z TERA ONAY SET Hu aaa aWE APM i ni TN HAAN (MONOS YEA. /rnNMHNMTEAL WE HO Nat ai 7255 50.00 On The set includes 12 8.00 Rhombohedral System Orthorhombic System Monosymmetric System 8.75 7252 7254 7250. Models, Atomic,*Kekule and von Baeyer, consisting of 15 nickel-plated binding posts with two clamps, 20 black balls with four connecting posts each, 10 red balls with two connecting posts each, 30 white | balls, 10 yellow balls, 10 green balls, 10 violet balls, and 10 silver colored balls, each with metallic tubulations to slip on the connecting posts........... 7252. Models, Valence, Nead’s. The blocks representing the positive elements are provided with pins which fit into corresponding holes in the blocks which represent the negative elements or radicals. each block is a clip for holding a card on which is printed the symbol of the element represented. With these blocks, valence and equation writing are made perfectly clear. _ t blocks for univalent elements, 6 for bivalent, and 4 for trivalent, half of each being positive, and 100 printed cards for symbols of elements and radicals. ... 7254, Models, Crystal, Set No. 1, of lime-wood. These wooden models are of an average size of 2 inches, packed inta{neat cardboard box with divisions. The set consists of 25 models as follows: Cubic System 1. Cube 13. Obtuse Rhombohedron 2. Regular Octohedron 14. Acute Rhombohedron 3. yg Pentagonal Dodecahedron 15. Hexagonal Scalenohedron 4.4 Rhombic Dodecahedron 16. Hexagonal Bipyramid 5.4 Tetrakis-Hexahedron 17. Hexagonal Prism and Basal Pinacoid 6. Triakis-Octohedron 7. Icositetrahedron 8. Hexakis-Octohedron 18. Macro-, Brachy-, and Basal Pinacoid 9. Regular-Tetrahedron 19. Macrodome and Brachy Pinacoid 20. Brachydome and Macro Pinacoid 21. Macrodome and Brachydome combined 22. Macro Pyramid Tetragonal System 10. Pyramid of the First Order 23. Ortho-, Clino-, and Basal Pinacoid 11. Pyramid{fof the Second Order 24. Prism and Basal Pinacoid 12. Prism and Basal Pinacoid 25. Hemi-Pyramid POE CCl stair en otras toe eat ae a enn we Sear TEN Ta Bae 7255. Models, Crystal, of lime-wood. This set is a continuation of Set No. 7254, and consists of 25 modelsas follows: Cubic System Combination of 1. Octohedron and Cube 14, 2. eB and Dodecahedron 15. 3. Cube and Dodecahedron 16. 4. Dodecahedron and Icositetrahedron 17. 5. Cube and “ 18. 6. “and Triakisoctohedron Gs “and Tetakishexahedron 8. “and Tetrahedron 9. and —,Tetrahedron a 20. 21. 22. Tetragonal System Combination of 10. Prism Second Order and Pyramid Second Order 11. Pyramid First Order and Prism Second Order 23. 12. Pyra First and Second Orders 24, 13. Tetragonal Sphenoid 25. PGE SEbs cits es ee ae ee ees mes Rhombohedral System Combination of Rhombohedron and Prism First Order i eu “« Second Order Pyramid First Order and Prism Second Order Me a e ee “First Order Pyramid Second Order “ce “ “ Orthorhombic System Combination of Prism-, Brachy-, and Basal Pinacoid Macro Pyramid and Basal Pinacoid Orthorhombic Sphenoid Prism and Sphenoid Monosymmetric System Combination of Hemipyramid and Clino Pinacoid m and Ortho sf Prism-, Clino-, and Basal Pinacoid 7260 7288 7292 MOLECULAR WEIGHT DETERMINATION APPARATUS, Beckmann, for depression of the freezing point, for both hygroscopic and non-hygroscopic solutions, consisting of zinc pan with outlet, cooling jar with nickel-plated cover, air jacket with rubber stopper, freezing tube with rubber stoppers, filling pipette, stirrer consisting of a platinum ring (approx. 2.1 grams) on glass rod, sulphuric acid tube with drying bulbs for hygro- scopic solutions, mercury trap with pipette for non-hygroscopic solutions, glass syphon to draw off cooling mix- ture, stirring ring for cooling mixture, “seeding”? device, consisting of test tube and rubber stopper, glass tube for drawing out into capillary form, with pinchcock and rubber tubing. Note—In the illustration the sulphuric acid tube with stirrer passing through it is shown in position. In the side illustration is shown the mercury trap for non-hygroscopic solutions with stirrer passing through it, and mercury pipette. 7260. Molecular Weight Determination Apparatus, Beckmann, complete as above described, but without Beck- mann thermometer, reading device, auxiliary thermometer for the cooling jar, or Ce. ring for ENG SEIT RET Pie eye rca nies oh peo ae gio hed wa ASD ANS Mad eh ae tery nal tn ki tiAts o he alld ees . 22.00 @261; “Metallic: Gover: for cooling jars.c6 8.5642 Gale eho ee ie bs Shee Wises Fa eee Oe Seas Pees BREAD 4.50 M262 GLAMCH PANzawlthrOutle bs naco8 oes asset eee eee ee tar a eet aR PTT) Lode ape ts oe nal DONTE REE ea reo 2.80 M2OSs%, GATE DACK Obscsrsics eas cae Cath Lok Labs Laide ome ne peg ok Sa nled eae iNia abe Ru Ney & Bess Aveat habeus eos aus Cater Rea ae -90 RAGA Ls: | PE COZAIE ST UDC sei coc rch tact Ae secede heb Ute aie Mena Pat yg Race Ak ae gee cean MARR cea aha etl sy Shei -90 7265. Sulphuric Acid Tube, for hygroscopic solutions..............0...0.00 2000 1.30 7266. Stirrer, platinum ring on glass rod, approximately 2.1 grams of platinum......................... 5.00 7267. Mercury Trap, for non-hygroscopic solutions... . 0.0.0.0... 00 eee 1.20 TZOSi2 SV DNOM aes cee cate eh ner oe tare eee TRS es ha ee ala Datak oh one RU DSeu crea steam sks, eatra UAL eceet fad be ... 1.20 7269: (Stirring Ring; for-cooling mixtures: 3 bi5-5 econ « Micke dae pte es Aes ated sh deed age Geena Suites Rene ws ane kates oe OO 127 oe OMAN ESP Pebter.o 30.5. h eee d ae scexcger eh gions GRE rae HS oe AS a Grea eae ee ANG 2 aL AS see ee aac eck 1.20 2097. Glass Jar, 7 inches high by 5 inches diameter..............0 00000... 0 0 oe ... 1.10 9568. Thermometer, Beckmann, with scale reading downward in 1/100° divisions. Without Bureau of Standards CORUM CALE Miu p atrcuctita ho tae cies thier ee MAR GS Sp ciekn hace skaters yee Ne ern gate ese arr ake alent mre ne 18.00 9569. ditto, but with Bureau of Standards certificate........000000 000 eee . 30.50 7272. Thermometer, Heidenhain, specially designed for study involving the depression of the freezing point. With enclosed scale reading in 1/100° from +1° to —5° C. For many purposes this thermometer is more convenient than the Beckmann or Differential Thermometer, inasmuch as it requires no “‘setting.”’ Totallength 500 mm.............. oe erm A ae itr nies ia area chs otal Oa 12.00 7273. ditto, but with Bureau of Standards CELL CALE ee oe enemas Senn ena tea _. 24.00 7274. Auxiliary Thermometer, for cooling mixture, reading from —20 to +40° C, in 1° divisions. .... .. 1.50 Cryoscopes, see page 209. 7280. Molecular Weight Apparatus, Beckmann, consisting of boiling point tube with steam jacket and fittings, asishowa nell luUstrattOne evo. 2 ciea ce mun Seton ae ive clin anc Ritles a tre a Uri ees Ra ese Se Bes Ne ... 10.50 7281. Boiling Point Tube, only, with fittings, as used in above Molecular Weight Apparatus....... ... 4,00 7282. Steam Jacket, only, with fittings, as used in above Molecular Weight Apparatus................ 7.50 7284. Molecular Weight Apparatus, Menzies, for the determination of molecular weight of dissolved substances by measuring the lowering of vapor pressure of the solution, and of easily volatile substances by measuring their vapor densities. No thermometer or other accessory apparatus is required.. 10.00 436 A -R. fF HH U R H. T H OF M AS G. Or OMe SR 2A, UND © 7288. Boiling Point Apparatus, Cottrell, constructed entirely of glass, making possible a perfect equilibrium between the two phases and at the same time enabling an exact determination of the temperature of this equilibrium when both phases are under the same external pressure. The ground-glass stopper will take Beckmann Thermometers, but these thermometers are not included in the price of the outfit. See F. G. Cottrell, Journal of the American Chemical Society, 41, 721 (1919). The apparatus we offer embodies the modification suggested by Washburn and Read, Journal of the American Chemical Society, 41, 729 (1919)............ ere coe ELEN aie k, 30.00 7290. Boiling Point Apparatus, McCoy, consisting of a graduated vessel with water jacket. See Journal of the American Chemical Society, April, 1900. The apparatus is now made with ground joint instead of cork stopper as shown in illustration............ ernest Lane eae Roe apes 5.70 7292. Boiling Point Apparatus, Jones. A glass vessel with ground-in stopper and side tubulation....... 5.25 9566. Beckmann Thermometer, with scale pees ee in 1/100° divisions. Without Bureau of Standards certificate... : : : Resse ree OP aw secant Shes ee 18.00 9567.) ditto, but with certificate.........0.......... para yolract eee © RNAS CAAA Fees SA Speah ee AB gS 30.50 7300—(1/6th actual size) . 7300. Mortars, Glass, with glass Besee Capacity, OUNnCeS...4 .uGss aoue yee Ape he eer ge Se rere ree 2 4 8 16 Inside diameter, inches.......... ites tay eee ee ee 24 34 4 4s Baths. 2 ccs ence oe Sat sitet Ge te Ae slag Sein te Caen ecoas OAE 45 -60 75 1.30 7301. Pestles, only, of glass, for No. 7300 Mortars. Fits mortar size, ounces... F Are Aenea Be apnea soe ae 4 8 16 Each. Masts ee Berle hire eats Sater Bcnea ectitnae eM in, Coeds -16 -16 16 .16 7304—(1/6th actual size) 7304. Mortars, Porcelain, with spout and pestle, glazed outside and rough inside. Grinding end of pestle is also lazed. : Ouade diameter, mm..... 65 80 110 —_—s:130 150 | 175 200_ 260 Batches cea tee 38 66 1.00 1.50 2.10 2.90 3.80 4.95 ly, for No. 7304 Porcelain Mortars. E TAO aE errr lef cies 65 go. 110 ~=—«130—S 150,175 200260 Bach: 4c ca eee 15020 .30 45 .70 .90 1.10 1.30 , Porcelain, with oe and pestle, glazed inside and outside. Grinding end of pestle also glazed. 7308, MorlarG uiside diameter, mm. 65 s0 {10 30 50 200. 280 aC esi oo tenheeetee are -50 “85 1.30 1.95 2.75 3.75 5.00 6.50 , only, for No. 7308 Porcelain Mortars. : es Fee ET arate TMM 5,5 sees 65 80 110 130 150 175 200 260 Bachised oie sities gocnit 12 .20 28 .40 .70 .90 1.10 1.30 7312—1/6 actual size) 7312. Mortars, Hard Acid-Proof Stoneware, so-called ‘‘ Wedgewood,” with pestles. Sizes up to and including No. 5 have solid stoneware pestles, while the remaining sizes have wooden and stoneware pestles. Number: . oss. es2 cee nok 4 0000 00 1 8 5 i 9 12 Outside diameter, inches... 3 4 4i 62 8 10 113 14 Wachite sh aces shavineihat : 1.00 1.25 1.55 2.10 2.95 4.30 6.40 10.50 7313. Pestles, only, for Stoneware Mortars. For mortar No......... . 0000 00 ‘ 9 12 Wahi ce costae saps : : : 3 sf é < . 2.10 3.50 7318. Mortars, Iron, with pestle. ACOA CADACLEV cau Gass cen bed oa a ee dg Ba ahaeasane ee 1 pt. 1 qt 1? qt. 33 qt. 5.qt. Outside diameter, inches.......................00.. 5 53 63 84 10 1.25 4.25 7320. Mortar, Spiegel, of forged tool steel, for powdering spiegeleisen, white cast iron, ete. Mortar is 5 inches high and 3 x 3 inches outside, 33 inches deep by 12 inches diameter inside. Pestle is 10 inches long, with rounded end 13 inches diameter, fitting closely into the mortar............ _. 20.80 7322. Mortars, Iron, Buck, for grinding and amalgamating. By rotation of the miller a large sample of quartz may be ground in contact with quicksilver. Diameter, inches.................. 63 Be Cheol sense a an ee SS EE ED Ee SA er te Pee MN aoe tis 13.50 18.00 7324. Mortar, Diamond, Leeds, of hardest steel. Inside diameter of mortar 22mm............-- ... 3.10 7326. Mortars, Diamond, Plattner, of hardest steel. Diameter of pestle, mm............---. 1 5 PRCT ie cece 2 Oe ee Oso eat A Te Pei titaty sea Stee eee ore 5.25 7.30 7328. Mortars, Agate, carefully selected. With agate pestle. Dimensions given are over all. Diameter, mm... 35 40 50 65 75 90 100 110 120 Bah esc. ac ers west 3.25 3.50 4.25 5.00 7.50 12.00 15.00 16.00 24.00 438 7330. 7332. 7336. 7338. 7339. 7342. 7343. 7330 Motor, Water, for direct attachment to faucet. A 4-inch motor of simple construction, furnishing } h.p. on 80 lbs. water pressure with a free speed of 4500 r.p.m. Because of the silent operation and ease of control, this motor is very convenient for laboratory work, supplying sufficient power and speed for a great variety of processes. With grooved pulley for round belt drive........ 5.25 Motor, Water, suitable also for use with steam or compressed air. A clamp not shown in cut is furnished with the motor for convenient attachment to a support either in vertical or horizontal position. The motor is 5 inches diameter, and yields a speed of from 2300 r.p.m. at 20 lbs. pressure to 4200 r.p.m. at 60 lbs. pressure. Inlet pipe is furnished for }-inch i.p. thread.................. 9.70 Motor, Electric, for operation on primary or storage battery circuits up to 8 volts. A convenient motor for laboratory purposes where small power is required, such as in the operation of stirring devices, etc. The motor is finished in gray and black enamel, neatly mounted on wooden base with brass binding posts. The grooved pulley is ? inch diameter and the size of the motor proper is 34 x 4} RO pI MOS oxic ode eyes chs path s a eoa echelon e eet inate ith omentum nhs idaumntend aah IAL 4 wT Races ae ... 5.00 Motor, Electric, L. & N. Constant Speed, consisting of a 1/50 h.p. motor with L. & N. electrical governor which controls the speed to within } of 1{¢. By means of the gear shift arrangement, shaft speeds are obtainable of 12, 30 and 60 r.p.m. Because of the slow controlled speed, this motor is found most convenient for driving of kymographs or other recording drums in a great variety of laboratory work, and also for stirring devices and many other purposes in the laboratory where slow, constant, predetermined speed is required. The motor is supplied with 34-inch shaft and three-way cone pulley taking }-inch round belt. For 110-volt die... .. 2 ee 100.00 ditto; but: for 110-volt,60-cy.cle; a Gav yoo SES eek es es Fe ee oes eet 100.00 7342 7343 Motor, Electric, with grinding and polishing attachments, and with universal winding operating satis- factorily on either 110-volt direct or alternating current, 25 or 60 cycle. Three speeds are possible by means of a switch in the base. This motor was primarily selected for use as a source of power in laboratory work, but the grinding and polishing attachments furnished will be found very use- ful in any chemical laboratory, and they are, therefore, included with the outfit as it is prepared for the manufacturing jewelry trade. The motor is rated at 1/30 h. p., and gives approximately 1200 to 3600 r.p.m. on alternating current, and 2000 to 4000 r.p.m. on direct current. It is 5} inches square at base, length of shaft 11 inches, height of motor 7; inches. The outfit regularly includes one each tapered mandrel, left-hand thread; }-inch grinding wheel chuck, sleeve for 3- inch grinding wheel, brush wheel 2{-inch diameter by s-inch face, and small pulley for round belt. With 8 ft. cord and plug for swivel lamp socket................ 0500s eee eee euee 34.50 Polishing Head, for belt drive; equipped with } inch steel spindle 10 inches long, provided with a taper screw on one end and a three-jawed chuck, capacity 0 to | inch, on the other end; and with flanges for holding a wheel * inch thick. The pulley is 2} inches diameter and will take either | inch round Or finch flat: Delivers Gira ite ood wea ceiacesedue ar earn et bse Gon bes Sao aA eee eat as pea ae rie oo 7.00 2753 7346 7350 2753. Motor, Electric, series wound type, 1-25 h. p., with pulleys; universal, operating equally well on 110 d.c: or 110 a. c. 60 cycle. Mounted on a neat base in which is concealed a rheostat for controlling the speed. This is the motor regularly supplied with the Parr Standard Calorimeter... 30.00 7344. Motor, Electric, Laboratory Slow Speed, with single speed reduction on worm wheel shaft, which reduces the speed of the armature to 32 r.p.m. at the pulley. This motor is recommended for laboratory stirring, and other purposes where motion rather than power is required. It is rated at 1/24 h. p. and there is a loss of about 40% due to worm gear transmission. The worm wheel and worm are submerged in grease, which insures quiet running of these parts with the least friction and wear. The pulley is l-inch diameter, grooved for }-inch round belt. For 110-volt d.c..............28.00 7346. Motor, Electric, Cenco Friction Drive, consisting of a small compact 1/40 h.p., ventilated type motor, mounted in a special frame which provides for clamping on a vertical support with the motor shaft either in vertical or horizontal position, and with the friction drive permitting variation in speed from 0 to 3,000 r.p.m., the full speed of the motor shaft. The shaft is provided with binding posts for the rotating of anodes in electrolytic analysis and with two chucks for the rotating shaft, the smaller one taking wires from 12 to 18 B & S gauge, and the larger one glass or other rods vary- ing from 15/64 to 17/64 inch diameter. The vertical and horizontal shafts are provided with grooved pulleys 3-inch diameter, taking 7,-inch round belt or cord. This motor is regularly supplied with { our Rotating Anode and Stirring Apparatus No. 4784. For 110-volt d.c.................. 31.00 7347. ditto;(but- tor L10-volt; 60=¢y CleyaiGoc: 06 crn a heen Biv pis or New aux ed mittee Sa wen lease ma sd ohana: 31.00 7348. Flexible Shaft, 12 inches long, for use with Nos. 7346 and 7347 Electric Motors. With guide to provide bearing for lower end and with solid chuck to hold }-inch rods. Can be attached to support by any ordinary right angle clamp.......... bis ean Uipiomiae hae haba 2 Bit MORES pk ses peceneske ae 3.00 ELECTRIC MOTORS FOR POWER DRIVEN LABORATORY APPLIANCES. The electric motors listed above are such as required in laboratory work where motion rather than power is the prime requirement. The following series of motors is selected for permanent installation where power and more or less continuous operation is required. The variety is sufficient to operate all of the power driven appliances listed in this catalogue, such as grinders, crushers, air compressors, air pumps, shaking apparatus, etc. I-R Single-Phase Induction Motors, Repulsion Start Type, for overload starting duty. These motors are recommended as the best small alternating current motors for developing a maximum starting torque with a minimum starting current, and are adapted for air compressors, air pumps, grinding and crushing machines, and other service requiring a starting torque considerably in excess of running torque and frequent starting under full load. These motors will carry overloads of at least 50%, and will start under loads equivalent to twice their ratings. They start as repul- sion motors and after reaching speed operate on pure induction principle. The brushes and commutators carry current for only a second or two when the motor is started. Single-phase induction motors are necessarily constant speed types. The speed of such motors does not vary appreciably under varying loads, nor is there any practicable method of varying or regulatng the speed of such motors electrically. The motors have four 12-inch leads brought out through the field ring. Each lead is tagged so that connections may be readily made for either 110 or 220-volt circuits in accordance with directions supplied with each motor. The flat pulleys are 2, 3, 3,3 and 4-inch diameter, respectively. | | Approx. Watts Approx. rm ie Romesaatee Mowe Jevtes | vase | 7. ABISE cg 7 pay |—eene—| oe | Load | Load Net | P’k’d. 7350. Motor, Electric, as described above...| 60 |1100r220| 4 | 1750] 85 | 300 | 33 | 43 | 64.00 7351. es ri Hs “ 2.) 60 |1100r220} + 1750 | 125 | 570 67 90 | 92.25 7352. a “i a a: “...| 60 |1100r220} 2 1750 | 130 | 800 95 | 140 | 114.00 7353. ie in e a eae 60 |1100r220; 1 1750 | 145 1060 | 100 | 145 | 124.75 7354. * ia ie a < 60 (110 0r220 2 1750 | 210 | 1930 | 160 | 220 | 173.50 440 7356 7360 _ Split-Phase Induction Motors for 110-volt, 60-cycle a.c. These motors have split-phase windings, with starting coils which carry full line voltage at starting, but which are cut out of circuit by means of an internal automatic centrifugal cutout after the motor reaches speed. They operate on the simple induction principle, without brushes, commutators, or insulated windings on any of the moving parts. Nos. 7356 and 7357 have a 14-inch diameter pulley grooved for }-inch round belt, while No. 7358 has a 13-inch diameter pulley grooved for 3;-inch round belt. ° oe Approx. Watts Approx. Weight lit-Ph: ion Mot ‘ycl ; aie el igan kee i Split-Phase Induction Motors Cycles | Volts | H. P. RPM. No Full Price Load Load Net P’k’d 7356. Motor, Electric, as described above..| 60 110 | 1/30 | 1750 35 70 10 16 25.00 7357. ne re ee i “| 60 110 | 1/15 | 1750 75 130 18 24 30.50 7358. ES i oy — «| 60 110 | 4 1750 80 180 23 30 35.50 Direct-Current Motors, Ventilated Type. These slightly compound-wound motors operate very much like shunt-wound motors, as the slight variation in speed under varying loads will not ordinarily be objectionable. Such motors have distinct advantages over the plain-shunt winding, possessing better starting torque, being to some degree self-reguiating under overload and less likely to be burned out by excessive load. While this compound winding is more expensive to make, we believe these motors will prove more satisfactory for power purposes in laboratory work than the plain-shunt windings of equivalent ratings. Suitable starting rheostats are supplied with each motor, with complete directions for starting, operating and reversing. The 3, 3 and 1-h.p. motors have 3-inch diameter flat pulleys, while the 2-h.p. motor has a 4-inch diameter flat pulley. | Approx. Watts | Approx. Weight es Approx. a D. C. Motors, Ventilated Type Voltage| H.P. IR p.m. No Full ae mea Price Load Load 7360. Motor, Electric, as described above......... 110 3 1750 90 525 15 105 81.75 7361. a cs a See rtencronen aon 220 $ 1750 90 525 15 105 81.75 7362. fs me ee oe ot Eee 110 3 1750 | 105 720 110 160 | 104.75 7363. . i i ee He intrcvenbvarcell OLL0 2 1750 | 105 720 110 160 | 104.75 7364. a re es ie Pe Badge ne rs 110 1 1750 | 105 920 110 160 | 110.82 7365. - ne Pee Gateant aa Nee 220 1 1750 | 105 920 110 160 | 110.82 7366. a a3 oe i e GAma eae 110 2 1750 | 300 | 1800 160 220 | 156.50 7367. “ e ae ae See orate el aeO) 2 1750 | 300 | 1800 160 220 | 156.50 Direct-Current Motors, Two-Pole Ventilated Type. These are shunt-wound motors, with the exception of the 1-h.p. size, which is compound wound. It has been found that in this size motor a slightly compound wind- ing is better adapted to general service than a plain-shunt winding. The frames are ventilated type, permitting free circulation of air. ‘ ; The z;-h.p. motor has a 13-inch diameter pulley grooved for }-inch round belt; the 75 h.p. a 13-inch pulley grooved for 35-inch round belt; the j-h.p. a 1j-inch pulley grooved for ;;-inch round belt; and the }-h.p. a flat pulley 2 inches diameter. Approx. Watts Approx. D. C. Motors, Two-pole Ventilated Type Voltage| Winding H. P. Peek a Sai 4 wOVeighto) Price Load | Load Net | P’k’d , Electric, as described above...} 110 Shunt ay 1750 | 35 80 12 17 29.00 ae) ee en te as DRO a | 1750| 35 | 80 | 12 | 17 | 25:75 7372. “ “ “ “ “410 es io 1750 | 40 140 16 23 33.75 7373. ‘6 6 66 “ Ce Fal e220) ‘s ie 1750 40 140 16 23 30.50 7374. “ 6c se “ fee el) 10) t 1750 | 55 170 16 25 35.25 7375. 6“ “cc 6 66 “cc ke 220 ee t 1750 55 170 16 25 32.25 7376. “ “ te fe CS eal EEO) Comp. 4 1750 | 70 280 82 43 46.50 7377. “ “ “ se £6" 28h al 220 ‘ + 1750 | 70 280 82 43 46.50 7380. 7381. 7384. 7385. 7386. 7387. 7390. 7400. 7402. 4384, 5702. 5703. 5705. 5683. 5684. mM ITM i 7380 7390 Countershaft No. 1, for use in power transmission with small laboratory motors. The shaft is 12 inches long by }!-inch diameter. Pulleys are 1, 2, 3 and 4 inches diameter, grooved for % or 7¢-inch round IBelieeerectctes ats ota eee et aoe aes ne ea om ates anna ln ed Adc Py Saat oh ere One NE eMart Renal Ati 2.50 Countershaft No. 2. Very convenient as a speed reducer or speed accelerator. The shaft is 3-inch diameter. With two pulleys 4 and 6 inch diameter; cone pulley 1, 13, 2 and 23 inches diameter. All pulleys are grooved for ;s-inch round belt.............. 0.0... c eee cc eee 3.50 Speed Reducing Gear No. 1, geared 48 to 1. The diameters of the three-groove driving pulley are 2, 3 and 4 inches; of the two-groove driving pulley 2 and 4 inches; all grooved for 7 or }-inch round belt. The round plate may be removed if desired, and direct connection made to shaft...... 7.00 Speed Reducing Gear No. 2, geared 48 to 1. In this device the gears are enclosed in a case which is filled with grease. All bearings are perfectly lubricated so the gears will run silently and without atten- tion for a long time. Diameter of fast running pulley 4 inches; diameters of slow running cone pulley 1, 14, 2 and 24 inches; all grooved for 7 or j-inch round belt.................... 10.50 Speed Reducing Gear, Precision, with constant oiling device on high speed shaft. The large pulley has three grooves of 13, 34 and 6 inches diameter while the small pulley has three grooves 1, 2 and 3 inches diameter. Both shafts are 3 inch diameter so that the pulleys are interchangeable. The reduction is 100 to 1. This device is specially made for laboratory work............... 32.00 Extra Gear:tor téeduction:of 200: to: Lee. ean tas Sees ss abs Ss nes cee eee as ee a 5.00 Motor Generator Set, for operation on 110-volt, 60-cycle, single-phase, a.c. circuit. Delivers from d.c. end 23 amperes at 110 volts. Maximum current consumption of a.c. motor 375 watts, and of d.c. motor 275 watts. This set is recommended where permanent installations are made for electro- lytic analysis where only a.c. lines are available. With the set is furnished a field rheostat to vary the voltage so that with the rheostat furnished with the Braun Electrolytic Outfit for control of the electrolysis current, both the voltage and amperage are independently controlled at the will of the OPeCLatOr: cocsuvraiies Gham ue isie ess 265.00 7400 7402 Mould, Pouring, of cast iron, with three conical cavities 2 inches in diameter; with wooden handle... 1.10 Mould, Pouring, of cast iron, with nine hemispherical cavities 13 inches diameter.................. 1.25 Moulds;/Cupel, of brass: ‘Size, mchess.. 025... pac gpodaraee i saees dexvavnbbavagts 1} 1} i PaO Ee eo aes CAE Ae ret a sve demi ieee Geteee eet 4.00 4.70 5.50 Muffie, of Clay, for use on No. 5700 Fletcher Combined Muffle and Crucible Furnace. Inside dimen- SIONSS S DY aie DY OR AN CHES ikea dene en oo oy ot Paes era ce nlite oa oie oa Na. eget earl nde 2.75 Mufile, of Plumbago, for use on No. 5700 Fletcher Combined Muffile and Crucible Furnace. Inside dimen- sions 33 by 23 by 64 NICHES ey ge eh neces Ceara manera Mop nh wean ri ae iD Atak) Aad mee rae 4.10 Mufiles, of Clay, for use with No. 5704 Wiesnegg Muffle Furnaces. SIZE“ CHES es hecacvs serrate cera ech leer Mian ieh ein bn iia Ba nea eat Sean A ae 63x4x25 10x6x4 Bachicn eit ere hak eee Bene en aa ened taba tNaualits fel ete ea 1.35 1.60 Domes, Perforated, of Plumbago, for use with No. 5684 Muffles in Fletcher Muffle Furnaces No. 5682. TO Mt TURMACE NOs, acne ee nias A Wsadcnicn eee weeny aut 3 4 5 BON, oie cress Bhs erm Tig oe aut nee PR ee ele 2.85 3.15 3.85 4.55 Mufiles, of Plumbago, to fit Fletcher Muffle Furnaces No. 5682. Toit furnace NO uot sokh es ie Coe Ree a 3 4 5 6 Inside dimensions, inches..................... 3x4x23 33x52x3 42x63x4 6x81x4i ahs ee Ue hee hens paca baeee aeons 2.75 3.50 4.25 5.00 R T H UR FA. Te EO Me A 28 Cc O M P A N Y 7410. NEEDLES, INOCULATING 7420 7410 7422 cooly oy LY ‘oy LHW VU t] H te 7 ( 7411. 7412. 7413. 7414. TA15. 7416. 7418. 7420. 7422. 7431. 7432. 7433. 8303. 7434. 7435. 7438. 7439. 414 7418 7433—(Actual size) Needle, Inoculating; an 8-inch glass rod with 14 inches of No. 26 platinum wire fused'in end......... 75 ditto, but with 31 inches of No. 24 platinum wire fusedin end. ...... 1-6... sees eee eee 2.50 ditto, but with 31 inches of No. 26 Chromel wire fused in CNG ee ey ee aaa eee eee ts oat .40 ditto, but with 31 inches of No. 24 Chromel wire fused inend.......... o teaertAO Needle, Inoculating, Ravenel; consisting of a straight needle of No. 24 platinum wire 13 inches leng securely mounted in an 8-inch aluminum rod; with protecting and insulating sheath made of a glass: tubes. eee eR eee eg ee RS an . 1.50 ditto, but with 2 mm loop of No. 24 platinum wire... 0... 00-65 sere eee eee eee eee 2.50 ditto, but with 3! inches of No. 26 Chromel wire.......- 2... +0 ese esse eset eee ees 50 Needle Holder, Rosenberger, with hard rubber handle 2 inches long, remainder of aluminum; with slid- ing brass collar for holding wire needle. Total length64: an chess ..0 vis secee open een 0 she 9 50 Needle Holder, Kolle. The rod is composed for one half the lengh of hard rubber for insulation, and the remainder of aluminum; with carefully made clamp for wire needle. Total length 10 inches. MEA GCH co ek n cateide cs cs Pepa cc as a Soe es ren ines Pee al Ri, easter an eh Ae ale ela 75 Per dozen, each............-.-.-.-5- .70 Per gross, each................. 0.005. .55 Needle Holder, Rosenberger and Greenman. A convenient needle holder of the Kolle type for bac- teriological work, with an improved clamp to hold wire needle. The clamp is made of brass nickel plated, and the handle of aluminum and vulcanized fibre for inoculation. Each....... 1.00 Per dozen, each...............-..--.++ 90 Per: oross;, Gach: 2. 2 gone cee es ea pee 80 Aluminum Rod, 3; inch diameter, for making inoculating needle holders. Approximately 4 feet to an ‘ounce. Per pound........ i eeaen, LS Needle Holder, Aluminum, 8 inches long by 7 inch diameter; with one end tapered and drilled for No. 24 platinum wire. Will take No. 26 platinum wire by means of slight compression with forceps. Very convenient for making inoculating needles in the laboratory. Each................... 25 Inoculating Loops, Platinum Iridium. These loops are carefully made of exactly the inside diameters indicated; with fused (not twisted) joint. Platinum iridium wire, 157, is used because of its rigidity, permitting the use of somewhat smaller wire than when pure platinum is used. The wires are 12 inches long; and the Imm and 2mm sizes are made of No. 28 wire while the 3mm and 5mm are made of No. 26 wire. Size of loop,mm...............-.+- 1 2 3 5 Bia Chis aso cx eek one PES LR RE SG Re EE Gn PED CREO A 1.00 1.00 1.00 1.00 Platinum Wire. For making inoculating needles and loops No. 26 wire is mostly used, particularly for loops, but where a stiff needle is required for culture stabs No. 24 is recommended. Bee S PAU ee coy etree sce es ni nish pts ante A ED ATOR mee ROSE ASM 26 24 Bt £0 Oboe snes ea es are ig ota ease oes SEE eg eee ent 2.35 3.70 Platinum Iridium Wire, 15%, for makinginoculatingneedlesandloops. B&Sgauge.. 28 26 | 24 Pee TO0t ine oe he ea ohne 4.52 7.04 Chromel Wire, for making inoculating needles and loops, the only satisfactory substitute for platinum for this purpose; a nickel chromium alloy which resists destructive oxidation to a remarkable degree even at high temperature, and which is non-corrosive at normal temperatures. In coils 24 inches Mop cat 28 long. B&S gauge..........0-2 0s eee 26 24 22 Peri COilin cece hoes Bo ee oe Se he EES ES -10 -10 10 10 Loop Gauge. A set of steel rods exactly 1mm, 2mm, 3mm and 5mm diameter, neatly mounted in a wooden base, for conveniently forming inoculating loops in the laboratory....."° tence. 3.00 Needle Holder Support. A polished hardwood block, weighted for stability; with holes for supporting needle holders in an upright position. Number of holes.........-..----00000555 _ 6 12 ERGHG cess Be ee teed Hal Gee ee ie eg RN Sea ance eet 25 50 443 A R T H U_ R EA. T H O M A 5S CG -O IM -P- AN Y¥ NITROGEN DETERMINATION APPARATUS 7440 7442 7440. Kjeldahl Distilling Apparatus, complete for gas heating; consisting of No. 7448 Condenser and Ne. 7450 Heating Shelf with adjustable burners suitable for use on illuminating, natural or gasoline gas. Without glassware. Number of DUMMeTS.:3. 2 joo uk rae a eae ee a ee tre A atic ose 6 10 CHR 0 eect tsi ks gn Aas RL ae SE eh pee nes Bee se reser 68.50 104.25 7442. Kjeldahl Distilling Apparatus, complete for electric heating; consisting of No. 7448 Condenser and No. 7452 Heating Shelf with Gilmer Electric Heaters for 110 volts, to be connected in series of two on 220-volt lines. For complete wiring directions, see page 340. Without glassware. Niimber-of heaters: .ctscce costes cen ee os ea es es ar dus Grane Meck He SUSY 6 10 Pea Rditthadn e Seeece 82.25 133.00 7444 : 7446 7444, Kjeldahl Digesting Apparatus, complete for gas heating, consisting of No. 7450 Heating Shelf with ad- justable burners suitable for use on illuminating, natural or gasoline gas, and No. 7454 Ventilat- ing Flue with supports. Without glassware. Nim berzo fp urnelsas AME IP A IN. CY: WATER SUPPLY —_— 7502, 7503 7508, 7509 7480. Kjeldahl Distilling Apparatus, new form, with individual condensers, light and portable and offers the advantage of complete adjustment in all directions so that different size flasks and connecting bulbs may be used. Each burner is furnished with a removable protecting shield, and condenser jackets are of brass with condensing tubes of heavy block tin. With adjustable burners permitting the use of illuminating, natural or gasoline gas. Without glassware. IN TUM bersol CON deMSersshne enk lee eects eacromy he cakeen Mates hae tw a 1k Pe he en 4 6 Baltes wired nett ancien eta nen aatted weg hnings feet alc Ri Aes R ieony te Ae Nac ars me vat 2 ota Ss 55.25 60.00 7484. Digestion Apparatus, Fumeless, Sy. See Journal of Industrial and Engineering Chemistry, September, 1912. With this apparatus digestions can be made without the use of a fume closet in any place having a water supply and drain. All fumes are disposed of by means of a filter pump and the price includes filter pump, connecting bulb tubes, stand, burners and four 500-ml Pyrex Kjeldahl Flasks UNO AAD sesso est rte gnc en cy te oe amet fede Pe pele i oe eee be ee A ecg aes tee Pa eet 22.00 7485. Connecting Tube, only, as supplied with Sy Fumeless Digestion Apparatus.................... .70 7486. Manifold, only, as supplied with Sy Fumeless Digestion Apparatus......................0005. -80 7487. Support Stand and Burners, as supplied with Sy Fumeless Digestion Apparatus. Without glassware and: Tubber' tui gs. he ye so ketan ccstea maaan eteces a ioe dae esraeaN tae te oe peep alin Rea eased Niarcles e et aek 13.00 7490. Kjeldahl Distilling Apparatus for Single Determinations. Convenient where but little work is to be done. Complete as illustrated, including glassware..........0.0 00000 eee 7.50 7500. Kjeldahl Connecting Bulbs; spherical form, with one curved tip at top. Diametercotbu Wo Smee octets Saves eeton ee aol Ae ace ces pita senade etn nen eee 52 65 Bea CW see carseat nurse toe lag bs costae cores oh tt es on aca a anesthe reenact er .60 -70 10% discount in case containing 12. 7501. It GOs DUTIOR PROX sClASS: nhs Be Ae eG eR ee NA arenes eA volt hah anus th Uncut Au naan ig 1.20 1.40 7502. Kjeldahl Connecting Bulb, spherical form, with one curved tip at top, and with straight connecting tube for bending to any desired angle; diameter of bulb 52 mm...................0....0 00005 .55 10% discount in case containing 12. 7503. ditto: butiot Pyrex glassicciy aie atin se vein rete ee Ae eed Oe pie eee ee la eset earth 1.00 7504. Kjeldahl Connecting Bulb, Jennings, as used in water analysis. With tubulationin bulb.......... 95 10°% discount in case containing 12. 7505. GIGLO sDUTCOL Ay REXIOlASS 2p een ON ont een ON ates canna Cael mina yeah win ea Aa And) cad Rae A cee a eae 2.00 7506. Kjeldahl Connecting Bulb, Clark, with baffle plate in the form of a deep watch glass, which reaches to within 5 mm of the interior wall of the bulb and which effectually prevents any spray from reaching the exit holes. See Journal of Industrial and Engineering Chemistry, 12: 366 (April) 1920..... 2.90 7508. Kjeldahl Connecting Bulbs, cylindrical form, with two curved tips inside the bulb. Diameter OL Poulos IMM reais ton iecatea devises leven wenctv erence eo ig see Banteist incavaon ab het waren Ue tee aes 45 55 Length of bulb, mm e..095 te eid Bo eee gene ere ee ee ae PR 100 120 EACH), eits tein ce eed ee et es act An SAA na mle aber a ate -70 1.00 10% discount in carton containing 12. 7509. ditto; but: of Pyrexglass.4 ick 5.234 oon at ee weg Rea eh aE Ses SES 1.80 2.25 447 A R T H UR H. T H O M A S&S G (07 -M.- .P-sA:_.N?_-Y 7510 7510. 7512. 7513. 7518. 7520. 7524. 7525. 7526. 7530. 7531. | 7512, 7513 7518 7520 Kjeldahl Connecting Bulb, of Pyrex glass. Model of the Southern Cotton Oil Co. laboratories..... 2.40 Kjeldahl Connecting Bulbs, Hopkins, with single straight tubulation inside of bulb. Diameter-of Duly: Wnts ere bess cae om ee pens eyn room wb eae la e Oenes Gah Bare be AOS 50 65 Each.........- rates af ’ Mad ate Reese en ye : -60 -70 10% discount in carton containing 12. : ditto; but: of Pyrex: glass... e057 .0e oo creas hcg Andee ea PSEA EM Teg Se ... 1.30 1.50 Kjeldahl Bulb and Scrubber, Davisson, of Pyrex glass, capacity 200 ml; with three openings in the bulb of the inlet tube. The first steam passing into the bulb condenses on the inside surface, flows down about the small bulb and there acts as a scrubbing solution for the remaining vapors. See “A Scrubber for Ammonia Distillations,” by B. S. Davisson, Journal of Industrial and Engineering Chemistry, 11,0: 65 (May 1919) ic. 26 2 oi5 cea alin be pe noes cae Pyetd BEG RRR ieee ea 2.00 Kjeldahl Adapter, for insertion in the flask receiving the distillate. Used in connection with Davisson Kjeldahl Bulb and’ Scrubber. See “A Scrubber for Ammonia Distillations,’ by B. S. Davisson, Journal of Industrial and Engineering Chemistry, 11, 5: 465 (May) 1919.........-+ +010 +-> 1.00 OILY 7525 7526 Nitrogen Bulb, Vollhard, Improved, latest form...................... setae Poe ck ok Aare 4d Vea ... 1.30 Nitrogen: Bulbs PE rowis: <0 «ccc ane ese etay omcemusc aacmmh sede tne bee Gace eae aaes es EEN AR NOR an ee AN 1.10 Distilling Tube, Watson and White, recommended as a satisfactory substitute for the usual distilling bulb in the Kjeldahl method for the determination of nitrogen. The large bubbles of foam, in passing through the numerous small holes, are broken up, thus preventing frothing while distilling over ammonia. See Thomas Watson and H. L. White, The Journal of Biological Chemistry, 45, 3 CHEULU CTU) al Gillean teucenesit eee eg en wile tears Ac ieetec hon Reed cea ben x {oetr ct ite peat ie "50 Nitrogen Purifying Apparatus, Badger, for the purification of nitrogen in small quantities for laboratory use, complete with bottle and rubber stopper. See “A Nitrogen Generator for Laboratory Use,’ W. F L. Badger, Journal of Industrial and Engineering Chemistry, 2, 11: 1052 (November) 1919..... 3.75 Purifying Bulb only, without bottle or rubber stopper..............000 0000p eee tee eee . 3.00 448 7540. 7542. 7543. 7544. 7545. 7546. 7547. 7548. 7549. 73556. 7558. 8842. E) | | { i fq 8842 cet i le i / 7540 7554 "7556 7558 Nitrometer, Dupont, Latest Modification, as used by the manufacturers of explosives. For description see Journal of the Society of Chemical Industry, 1900, p. 182. Complete glass parts with iron support anidirtib ber CU Une sake chink es vacua Sits Sheed eee ee tron eae Ee Peatacataroay Jveine ds eens See 100.00 Nitrometer, Dupont, glass parts only, without iron support, but with 5 ft. of nitrometer tubing, as shown in illustration of No. 7540 complete outfit........0.0.0.00 00.000. 29.00 SEPARATE PARTS FOR DUPONT NITROMETER Compensating Tube only, part B ofillustration.............0 000. 1.90 Large Measuring Tube only, part C of illustration............... 000.02 eee 7.00 Universal Measuring Tube, of precision grade, made in accordance with the requirements established by the Dupont Company. Part C of illustration.............0000. 00.0. 10.00 Nitrogen Bulb Tube only, part D of illustration.......0.0 00. ee 8.00 Leveling Reservoir only, part EH of illustration... 2.22... -90 Reaction Bulb only, part J of illustration.... 0.000.000.0006 eee 7.00 Three-Way lube: only. seccc taurine ea lois eee ress woes ER I ae. -60 Large Iron a with six uprights fitted with rings, rack and pinion movement for leveling bulb, Ee Cee ele Re cee Eh NISL ey eC eee cana Ss a) SCRE MU yahoo ac N EDA Bip ine en Atel 70.00 Nitrometers, Lunge, with 3 ft. of nitrometer tubing. Intended for use with ordinary clamps and supports. GApacity 4 sg ecn ets a ee We ae Rees See 50 ml in yoths 100 ml in jsths BACHE Ope ee Ee THAT Gan mene eA ne ae WAP Ee 7.15 7.85 Nitrometer, Lunge, as used in the determination of nitrogen in gunpowder, nitroglycerine, dynamite, etc. Graduated from 100 to 140 mlin j5ths. With 3 ft. of nitrometer tubing. Intended for use with ordinary: clamps and SUpPPOrtS. 5¢4 54 wads digere hd make AE CFA GEA TA) DARE oa aaa Ae Re 8.15 Nitrometer, Schiff, graduated to 100 ml in jths. On support with reservoir, special clamp and 2 ft. of MitromMmeter CUDIN Ge v5.2 sven wses pe nae Aa earns Cuotemslskateuemanaias os 5 alk mela ian Sarwin Mee alae 10.00 Rubber Tubing, Pressure, Grayish Red, specially selected for use on nitrometers. Inside diameter } inch with 3;-inch wall. PGE LOO cites oe ido eae alS ol SENS ov Oe elo ig acre Began alae Abe Ghat eA GMS ceua eee sures 55 449 ae ova. fost Leet To hat # (ot Tort TTT, Za (Qo fo. aT 3%, 7562 APPARATUS FOR THE GASOMETRIC DETERMINATION OF ALIPHATIC AMINO GROUPS, VAN SLYKE. The nitrogen gas evolved from amino groups and nitrous acids in the reaction RNH:+ HNO.,=ROH+H,0-4N, is purified and accurately measured in a gas burette. A complete determination of the NH, nitrogen of amino acid requires but six to ten minutes, and the accuracy is equal to that of a Kjeldahl determination, i. e., within an accuracy of 75 mg of nitrogen. An indefinite number of successive determinations can be performed without disconnecting any of the parts. This method has been applied to varied problems, among which are study of protein digestion, both in vitro and in vivo; the determination of the nature of the amino acids yielded by hydrolysis of small amounts of protein, determination of free amino groups in fixing the constitution of various organic substances; and the determination of amino acid nitrogen in urine, blood and tissues. See Journal of Biological Chemistry, 12: 275, 1911, and 16: 121, 19138, also Abderhalden’s Handbuck der biochemischen Arbeitsmethoden, V, p. 995. The apparatus is now furnished in two sizes, the so-called ‘“‘ Macro” and ‘‘Micro” sizes. In the Macro size the reaction vessel is graduated to 10 ml and the gas burette to 40 mlin yoths. In the Micro size the reaction ves is graduated to 2 ml and the gas burette to 3 ml in 1/100ths. The gas pipette for shaking is identical for both sizes. 7560. 7561. 7562. 5953. 7566. 7567. 7568. 5953. 7569. 3595. 7570. 3232. Amino Acid Nitrogen Apparatus, Van Slyke, so-called ‘‘ Micro” size, complete as per illustration which shows the author’s working arrangement, including support, glass parts, clamps, pulley for shaking apparatus, leveling bulb, rubber tubing, etc., but without motor......................... 51.50 Reaction Vessel, only, for the Micro apparatus, graduated to2 ml.................0.0.0.0..... 28.00 Gas Burette, only, for the Micro apparatus, 3-ml capacity graduated in 1/100ths; with three-way stop- COC Kesehatan pad Pan eg ty Been nlsla mena eM © bas fora crag ae Reni ade oe ae ge ere Ia 9.00 Leveling Bulb, only, 23 inches diameter, 130-ml capacity, for use with Micro apparatus............. 1.00 Amino Acid Nitrogen Apparatus, Van Slyke, so-called ‘‘ Macro” size, arranged exactly as shown in illustra- tion of No. 7560, including support, glass parts, clamps, pulley for shaking apparatus, leveling bulb, rubber tubing, etc., but without motor.........00.0.0 0000.00 eee 56.00 Reaction Vessel, only, for the Macro apparatus, similar in appearance to No. 7561 but of larger capacity, VKC se SOTACUATCECOsL OTM) ate ince ddan th sed deiashcans a tacer estes ne hat? ota ba hit ane R atti ny teen Le on ey hed 30.00 Gas Burette, only, for the Macro apparatus, similar in appearance to No. 7562 but of larger capacity, tes Craduated to Om tse thsy vacss soc cea cotta cee Uae on yal pene ntee a dleae win ietaten: 11.00 Leveling Bulb, only, for use with Macro apparatus, 3 inches diameter, 250-ml capacity........... 1.20 Gas Pipette, new form for shaking, for use with either the Micro or Macro apparatus............. 2.80 Thistle Tube, only, with stem cut to three inches length, for use with either of the above outfits...... .20 Shaking Device, consisting of wooden pulley 4 inches diameter attached to clamp for use on any labor- atory support, with slotted eccentric and loose arm 5 inches long; as used for shaking the gas pipette in Van Slyke Amino Acid Nitrogen Apparatus and convenient for other similar WOT sed nor, Se nce the Re eal Td ye tule chs Puree ae Oo eaN ea Dee mW veered nity) CrP av Yon Wier A day eae hn ttn 2.20 Clamp, for supporting reaction vessel and gas pipette of Van Slyke Amino Acid Nitrogen Appa- RA GUISE iy. to rena eesti hse Mme Gee has hoped eae ears Cmca ett Gh pcs Nir afin hl neo Oeee ysis ne te deen reset Rh et er hate lia de 4.00 A R T H U_ R H T H OO. M A S € -Of M.-P. A IN ¥ OIL TESTING APPARATUS COLORIM ETERS for Oil Testing—See Lovibond Tintometer for petroleums and Wesson Tintometer for cottonseed oil on page 162, and Saybolt Universal Choromoneter for refined petroleum on page 161. i F | 7580. Fire Tester, Elliott, for determination of the flash point of illuminating oils. Of polished copper with alcohol burner and thermometer reading to 600° F in 2° divisions 12.80 9526. Thermometer, only, for No. 7580 Fire Tester, engraved on stem, range 30° to 600° Fin 2° divisions...... ......... 1.60 7582. Open Tester, Tagliabue Improved, for flash and fire tests of illuminating oils. Of polished copper with alcohol lamp and gas flame testing burner with regulating stopcock and wheel for the dip test. With paper scale thermom- eter reading from 10° to 220° F in 1° divisions, and CITECHIONS TOP USE yes soko ain ore ane Se Le 10.00 7583. Thermometer, only, for No. 7582 Open Tester, paper scale, range 10° to 220° Fin 1° divisions.................... 2.00 7584. Open Tester, Cleveland, for flash and fire tests, with tripod, Bunsen burner and thermometer reading from 30° to 700° F in 2° divisions, and directions for use.......... 12.00 7585. Thermometer, only, for No. 7584 Open Tester, engraved on stem, range 30° to 700° Fin 2° divisions................. 6.00 7586. Open Tester, Cleveland, Large Model, for flash and fire tests of high-grade lubricating oils. A heavy, substantial tes- ter made of cast brass with both alcohol lamp and Bunsen burner, thermometer reading from 80° to 640° F in 2° divisions, and directions for use.................. 18.00 7587. Thermometer, only, for No. 7586 open Tester, engraved on stem, range 80° to 640° F in 2° divisions.............. 9.00 451 A 7590. 7585. 7592. 7593. 7594. 7595. 7600. 7601. 7602. 7603. 7606. 7607. R YT -FooU CR H. T H O M AS Gc oO M P AN: ¥ 7590 7592 7600 Tester, Cleveland, A.S.T.M. Model. A Cleveland Tester modified to comply with the recommendations of the A.S.T.M. Committee D-2 on Lubricants and Committee on Standardization of Petroleum Specifications (U.S.A.). The sand bath used on the large model Cleveland Tester is replaced with a metal plate covered with asbestos board, and a bead of the proper size for testing the gas flame has been added. With Bunsen burner; thermometer engraved on stem, range 30° to 700° F in 2° Givisions: ‘and directions: TOr: USC « <-> Sse css ea ane die ee hk es Helped ee Mieamasse A ae Saaiods otedoues 18.00 Thermometer, only, for above Tester; engraved on stem, range 30° to 700° F, in 2° divisions... .. 6.00 Flash Point Tester, for Petroleum, Abel-Pensky. Latest model with clockwork for opening cover and depressing the test flame. With one thermometer 10° to 50° C in 3° divisions for the oil cup, and one thermometer 50° to 75° C in 1° divisions for the water bath. Certified by P. T. R. both as to apparatus and thermometers. In polished wood case with Aneroid Barometer mounted in lid, and with directions for use BE Al eiie cited triad cgi bene oea Rane te meal eed Sa ebayer tea wk seed UC AI RA Yok Oo aca can ee DRA ss 100.00 Thermometer for Oil Cup, with enclosed opal glass scale, cemented in brass collar; range 10° to 50° C in 3) divisions: “With: certificater ss ocr sesapsie e208: 5 v2.2 wget wrasse ; devices ©5500 Thermometer for Water Bath, with enclosed ep Eres scale, cemented in sme allen range 60° to 75° C in 1° divisions. With certificate. ASL aN terete é 3 Ss al si a 4.00 Aneroid Barometer, as supplied with see Flash Point fester With ee fee screwing in lid of case. 15.00 Flash Point Tester for Heavy Oils, Pensky-Martens. Latest model for gas heating, with thermometer 80° to 250° C in 1° divisions. Complete with burner for gas pis and certificate for ther- miometer:: “InSGASer vers none pale alae Ae ee oe gene erty ral ey rietyh eee ere Ree poke a tyne 80.00 Thermometer, enclosed opal glass scale, with brass collar; range \ 80° to 250° C in 1° divisions, as supplied with Pensky- \ Martens Flash Point Tester. With certificate...... 5.00 ditto, but range 40° to 160° C, in 1° divisions, for low temper- ature investigations. With certificate.............. 4.00 ditto, but range 200° to 400° C, in 1° divisions, for high temper- ature investigations. With certificate.............. 5.60 Closed Flash Point Tester, Tagliabue. A new and simplified form of closed tester approved by the A.S. T. M., and adopted by the National Paint, Oil and Varnish Association, The Paint Manufacturers’ and National Varnish Manufacturers’ Association, etc. It can be operated with either gas or oil to supply the ignition flame without any change in the appar- atus, with gas flowing through the oil chamber when gas is used. With alcohol lamp and two thermometers 10° to 220° F in 1° divisions, one indicating the temperature of the oil and the other indicating the eat of the water bath, and directions for use...... 48.00 Thermometer, for oil cup or water bath of No. 7606 Flash Point Tester. Engraved on stem, range 10° to 220° F in 1° divi- SIO aes pea ciety ee eons eh core Rene nae pt A eT Tae 3.00 rw a Ih 7610 7612 7610. Oil Tester, Hexagon, Electric, for the determination of flash and fire points in light and heavy oils, con- sisting of an electric heater with top of heavy polished copper and mounted on a heavy iron base. The equipment includes two double-walled Cleveland oil cups of polished brass and copper with covers. With electric sparking device, detachable, by means of which an arc can be produced above the surface of the oil, which permits the accurate determination of flash and fire points, as the surface of the oil is not heated by a testing flame. By means of a switch the electric heater can be operated at two heats, making it possible to test any oil. With oil cups removed, this device becomes a convenient electric heater for distillation, Kjeldahl determinations, etc. The diameter of the heating surface is 44 inches. With thermometer reading to 600° Fin 2° divisions. For 110- Vib CLR CUD ide casters Ut tga ey etl SV es Neely Aine aa aR a aipntc deat nates ethene Ra nk eS REL ORLA 50.00 9526. Thermometer, only, for Hexagon Electric Oil Tester; range 30° to 600° Fin 2° divisions........... 1.60 7612. Hydrogenation Apparatus. A copper retort 8 inches high by 4 inches diameter at bottom, with clamped- on lid and stirring apparatus for pulley drive, as used for building up oils or other carbon compounds by adding hydrogen or other atoms to the molecule. The top is provided with a brass tube 1}-inch diameter which reaches to the bottom of the retort for the admission of gas. Intended for pres- sures of about 2 atmospheres. As used in the laboratories of Columbia University . . ... 21.00 HYDROGENATION APPARATUS, designed for the treatment of liquids with hydrogen and other gases under varying degrees of temperature, pressure and mechanical agitation. Constructed of steel, consisting of a conical retort 4 inches diameter by 9 inches deep, with all joints autogenously welded. The bottom of the retort is provided with a 3-inch drain cock. The cover is secured in position on the retort with six bolts, and carries the agitator shaft, inlet tube for admission of the gases, thermometer well, relief valve and filling connection. Designed for a working pressure of 60 lbs. per square inch, to which all of the outfits are tested before leaving the shop. It is not possible to connect the apparatus directly to a high pressure gas line, and a pressure regulating valve should be inserted between the apparatus and the source of pressure gas. In using inflammable gases, such as hydrogen, all joints must be tight before attempting to operate the machine. A little soap suds applied at the joints will quickly indicate any leak, and a flame should not be used for this purpose. — ; The apparatus will be found convenient for hydrogenation of oils, deodorization of oils, blowing of oils, polymerization of oils, sulphonation, rendering, renovating, distillation tests with steam and inert gases under pressure and vacuum, etc. See “On the Catalytic Hydrogenation of Cottonseed Oil,” by Louis Kahlenberg and George J. Ritter, The Journal of Physical Chemistry, XXV, 2, (1921). 7614. Hydrogenation Apparatus, as above described, complete with wrenches and ring burner.......... 125.00 7618. Distilling Tube Receiver, for the determination of water in petroleum and other organic emulsions by the Bureau of Mines method. See ‘“‘A Convenient Method for the Determination of Water in Petroleum and Other Organic Emulsions,’ by E. W. Dean and D. D. Stark, The Journal of Industrial and En- gineering Chemistry, 12, 5: 486 (May) 1920. There is required for this method a No. 5334 Flask, 500 ml, No. 3905 Condenser, 375 mm, and a suitable source of heat. No. 6138 Cenco Electric Heater is convenient for this purpose. Tube Receiver only............................. 1.00. 7620. Oil Test Cup, for gasoline corrosion and gumming test. A hemispherical dish of copper, 34 inches diameter, With Dea ded Piles a aecey cae neo tercs see eran ate Sas th ener are tan SA TREN cece ia sala on Mienetitnc dal in ao : il | i ONG IM sto 5002 Bene | divastons cs ah o-0h Sete oe cage oe ans als ah omy Seay Sau tA un Sa 5.60 Thermometer, Distillation, engraved on stem, 385 mm long, range 0° to 400° C, in 1° divisions. Cor- rected for totalimmersion. As usedin A.S. T. M. test D-28-17.............000000..0..... 9.00 Sheet Iron Protecting Cover, asbestos lined, with door, for protecting burner flame in outfits Nos. 7628 to MOS Ls ee crib ezeres eulgl , Ohre Peete on ebla gal ries. alae wet sner dw NONE She INL AIM ag ate hha byron sane le alan tions ahh & 8.80 Heater, Cenco Electric, as described on page 341, with 6 ft. of cord and plug for attachment to any lamp SOCKS TOR TAO Volts ies spectre cer ae eae seeayidex Seeirde Soe rae septs aE eNOS GaP. tome Aarne EIA ts in 17.50 aitto but for2Z0-voltsecees ci side Shakes ae ona mae eos, erate aaa Dat ath MacoreeeeN peaie Maen, wireaal nda arlate 18.50 Heating Unit for replacement, for Cenco Electric Heaters. ROREVOL US aetaed ete cee ratte a ees Enna oem weete tenia yey ay Ae hn ores Sree mma han Catania 110 220 SB CMake hss oe ee ee ae Ato etre epbca torte ne Nene sss ch eandeacar Wrens co Leute eleach tava otk stoops oR 5.00 5.00 7640 7644 7650 } i n, for the determination of the carbon residue in petroleum lubricating Se ae eee as described in A. S. T. M. Standard Methods for 1918, p. 621, consist- ing of a hollow sheet iron block with removable hood and short chimney and the following acces- sories: Porcelain Crucible, 30 ml without lid, Skidmore Crucible, dp oz., without fittings put with lid, Iron Crucible, 200 ml with lid, Pipestem Triangle, 2} inch, Tripod, 53 inch, and Tirril meer This outfit has found wide use in U. S. Government Departments...... Ae ae es Sheet Iron Block with Hood and Chimney, for Conradson Carbon Residue Outfit............... F NoteE—This item is offered separately so that those having all the other items need not purchase the complete outfit. Viscosimeter, Scott, of polished copper, on tripod, with burner, thermometer reading from 0° to 220° F, i 20.00 in 2° divisions, and graduated cylinder 50 Moe oe wae ere Se bb! wy cay gt aeactanicicn ohn oe Scott Viscosimeter, engraved on stem, range 0° to 220° F, in 2° divisions... 1.20 iveri isti in 35 t erature of Viscosity Pipette, Dudley, delivering 100 ml of distilled water in 35 seconds at a temper oe i i erating upon the principle of a cylinder rotating in the liquid ee eon ee ee atari aight and at a known temperature. It consists ot a cylinder which by ‘means of a weight acting through a spindle, a eT is ae ee rotate in a test cup. This cup, in turn, is surrounded by a water or 01 pee used. a pe ath tenance of the desired temperature, measured by a thermometer for w ue Bree s ma " To the spindle which supports the cylinder, a revolution coat efistilled water and in the substance i ke a specified number of revolut : car eee totus cheese of comparison, or, in other words, gives a means of determining Bye Wy dig oN ale tee gibay Re Reet) MO | Re va ese etme dod cite randie yl aMiu® Greer iGo the ye teaers 48.00 the veer Ce EE aioe a eee Pn mia Test Cup, only, for Stormer Viscosi Eee ea eptee itn ee Rabies Duma S Ea he Cre aA: Revulvable Cylinder, only, for Stormer Viscosimeter......---- +++ +00 esr ernest 3.35 455 A R T H U_ R Ih T H O M A 5 Cc O M P A N_ Y 7654 SAYBOLT UNIVERSAL STANDARD VISCOSIMETER. The standard instrument for testing cylin- der, valve and similar oils with bath at 212° F, and the oil at 210° F; for testing reduced black oils, with bath about and oil at 130° F; for testing neutral, spindle, paraffine, red and other distilled oils, with bath about and oil at 100° F, or at any temperature from 70° to 212° F. It is equipped with an electric heating device, a U-tube steam heater and a gas burner, in addition to a turntable stirring arrangement. The bath liquid recommended is a paraffine, pale engine oil, of about 350° to 400° flash, to be used for viscosity tests at all temperatures. The substitution of oil for water avoids the com- mon difficulty arising from the mixture of water with the oil under test. Cold or warm water can be run through the U-tube when necessary to reduce or raise and accurately control the temperature of the bath, whether the heating element is steam, gas, or electricity. 7654. Viscosimeter, Saybolt Universal Standard, as above described. Without stopwatch, but with six ther- mometers and electric heater for 110 volts... 0.0.0... 0.00. ee 90.00 7655. ditto, but for 220 volts 7656. Viscosimeter, Saybolt Universal Standard, same as No. 7654, but with Stopwatch. For 110 volts 100.00 7657. GItCOs: DULSTORAZ OVO lt Smets ter hud et rood iol susie aged ON aa eatin as ea cent a dope iE an Net coo Recta aware als Merial ee ites 100.00 SAYBOLT STANDARD FUROL VISCOSIMETER, for the determination of the viscosity of fuel and road oils. This instrument is identical in general construction with the Saybolt Universal Standard Viscosimeter listed above with the exception of the outlet tube and the thermometers, of which only two are furnished with the Furol instrument, range 100° to 140° F, as the prescribed temperature for taking the viscosity of fuel and road oils is 122° F. The same flask is supplied with both instruments. 7660. Viscosimeter, Saybolt Standard Furol, as above described, without stopwatch, but with two thermometers and electric: heater for 1.110 voltsvs.) 155 cx, vests es nh Reed eats cae ety ok han on vane nani 90.00 7661. ditto, but for 220 volts............... ME iste Aol a sant eee hey oh oeen i: eee me te 90.00 7662. Viscosimeter, Saybolt Standard Furol, as above listed, but including stopwatch. For 110 volts.. 100.00 7663. dittoxbut:for 220 -voltseeH sono aie wettest enon ethno on eh ray ae ont oan ane aver) Sinbad 100.00 7666. Thermometers, for use with Saybolt Universal Standard and Furol Viscosimeters. FRAN Per aca eke s Se tena G ween wen iasnne 70° to 110° F 100° to 140° F 180° to 220° F ACH et esi tee tte ay ee Cea 3.60 3.60 3.60 5534, Volumetric Flask, Pyrex, for use with Saybolt Universal Standard and Furol Viscosimeters. With hemispherical: lip, G0-ml capacity... ooh; cog woecew aon 84 8 3K ddd G4 oid sane bade e ees 1.25 10% discount in case containing 144. 7667. Pipette, only, with rubber bulb, for use with Saybolt Universal Standard Viscosimeters......... .60 7668. Electric Heating Unit, only, for Saybolt Universal Standard and Furol Viscosimeters; with a 5-ft. cord and plug*tor lamp socket. Bor 1l0'volts).. 3i:) isc 2 aca 5 akan craceine Geek bance 2A As Adee 8.25 7669. dittobubdor 220 WOlts: te secede be tat ON tytn eten cog) oe a, Oh Oi a a Ree atonal Meike een 9.00 7670 7676 VISCOSIMETER, MacMICHAEL IMPROVED, Patented. This instrument is designed for the deter- mination of a wide range of viscosities on the principle of the force required to produce a definite relative movement of the fluid particles in a given time. As originally introduced, the range was limited from the viscosities of the light liquids to that of pure glycerine. Many important improvements have now been made and the instrument is adapted for the accurate determination not only of the lighter liquids, but also of very viscous substances, as, €. g., the heaviest and stiffest glues. The motor and governor are enclosed in a dustproof case, and a handle is provided on the upright for con- venient carrying. The ordinary lighting circuit is utilized for heating and operation, and the motor is universal, operating on either d. c. or a. ¢. The wires now furnished with this instrument are unstandardized, and it is recommended that customers inform us when placing order of the nature of the material to be tested, so that suitable wires may be selected for shipment. The manufacturers expect to furnish standardized wires at an extra cost in the near future. 7670. Viscosimeter, MacMichael Improved, Patented, as above described, with unstandardized wires, and Mmocortor: ALO wirnve cenive, aeem-oere a ok cosh kek SRSA EA eS 10x 10x12 aches ine peek tires Gop tneen een tera tite war RAMI CN 7 50.00 ditto, but with heating plate wound for 220 volts. Inside dimensions; IMCHESiaacc ¥ cccc econ cad AAAS Ler peu mika manera banks 10x 10 x 12 aCe eta te sat cn aoe maya oe pecan ausus ei eeeen SOE pR a andes ea 50.00 18x12x14 70.00 18x 12x14 70.00 Oven, Thelco Electric, Compartment, Double Wall, otherwise similar to No. 7830. Inside dimensions, 14 inches high by 8 inches deep by 18 inches wide, provided with a perforated aluminum frame dividing the heating chamber into eight compartments, each 4 inches wide by 6 inches deep by 5 inches high. This frame is supported one inch from each wall of the oven in order to provide a circulation of heated air. With removable heating plate, connecting cord and plug, but without thermometer. With heating plate wound for 110 volts.................0......... ditto, but with heating plate wound for 220 volts. ..... 0.00.00... eee eee eee Heating Plates, only, for use with Thelco Electric Ovens, wound for 110 volts. SIZE OLNOVENs INCHES s fad’: 5 unael Ltaedameate Riera totes See mae ae 10x10x12 1 BSAC He Sees oe a a ea oer daca eel cota ional pee enim cwtecm aeaaee erect 6.00 ditto, but wound for 220 volts. Size of oven, inches................. _10x 10 x 12 VCO Ae saceetccte ies cate calcd sh tm er TT LE eS Ora we emote ches 6.00 Shelves, only, for use with Thelco Electric Ovens. Size of oven, inches. . . 10x 10 x 12 VC He ese Ae recut amie tea ee a SV IS ky So SRC oar e cD ie mtran uae he tae 1.00 Pilot Lamp, 15 watts, for use with Thelco Electric Ovens... . 2.0.0.6... eee eee een 467 Gh Bait 120.00 eed et 8.00 ae 8.00 18x 12x14 1.25 75 7840 FREAS ELECTRIC DRYING OVENS. Constructed with a double wall of heavy asbestos transite, with cast aluminum frame and doors. The air space between the inner and outer walls is filled with air cell asbestos. The interior is fitted with shelf racks, allowing the shelves to be placed at any height. A small electric lamp is placed within the Oven, which is used for illumination and as a pilot light if so desired. By means of this light and the small window in the door, the interior compartment can be observed without opening the door, with the resultant cooling of the compartment. Type R No. 100 and Type HT No. 104 are finished with walls tinted brown, while the remaining Ovens of both series R and HT are finished in white. The heating element consists of a wire-wound resistance plate placed at the bottom of the Oven and which is easily removable when necessary. The Freas Patent Regulator is the essential feature of these utensils. It is made entirely of metal of robust construction, and seldom gets out of order. Its action depends on the expansion of a metallic tube extend- ing from the bottom to the top of the chamber, operating a lever which ‘‘makes”’ and “‘breaks”’ the contact without arcing. The lever is extended and serves as a pointer, operating on a graduated temperature scale on the outside of the Oven. When the pointer is set on the scale at the temperature desired, the indicated temperature is approxi- mately attained with some adjustment. For final adjustment, comparison should be made with the thermometer inside the chamber. The automatic temperature regulation maintains the indicated temperature with reasonable accuracy after the Oven has been on the circuit a sufficient time to thoroughly and uniformly heat the walls, and is most satisfactory under continuous operation. With an intermittent use there is always some loss of time after the indicated temperature is reached before uniform control is attained. A considerable time is required to reach maximum heat, in common with all electrically heated utensils, and for these reasons the whole con- struction of the Oven is designed for continuous operation. For instance, starting with a room temperature of 20° C, the compartment of Type R No. 100 Oven reaches 100° C in approximately 45 minutes, 150° C in2 hours 10 minutes, and 175° C in 3 hours 45 minutes. Starting with a room temperature of 22° C, the compart- ment of Type HT No. 104 Oven reaches 175° C in 1 hour 3 minutes and 260° C in 2 hours and 25 minutes. 7840. Oven, Freas Patent Electric, Type R No. 100, as described above. Inside dimensions, 12 inches wide by 12 inches deep by 12 inches high, on low base of cast iron, for operation from room temperature to 175° C by attachment to ordinary lamp socket. With thermometer reading to 200° C, connect- ing cord and plug. With heating plate wound for 600 watts at 110 volts................ 135.00 7841. ditto: but for 220 Volts xeenive ta.ener a eda ea Maret rece aaiee seam 8 Mayan ee Oke ..... 135.00 7844. Oven, Freas Patent Electric, Type HT No. 104, similar in appearance to No. 7840 but with four control switches at top. Inside dimensions, 12 inches wide by 12 inches deep by 12 inches high, on low base of cast iron; for operation from room temperature to 260° C. Recommended for use in baking tests on bread and other food, testing asphalt, enamels, rubber, high flash point of oils, etc. The heating plates are wound for 1500 watts, and, therefore, oven cannot be used on a 6-ampere lamp socket but must be connected directly to a line of this capacity. With thermometer reading to 300° C. For 110 volts...................... eee nt cen toast iert ta . 165.00 7845. ditto;-buttor.220 VoltsSiccac cians ae oe eee eae Rae h Vet ialabha Stati E eae: snlthee satena eee, 60200! 7848. Oven, Freas Patent Electric, Type FA No. 105. This utensil consists of a No. 7844 Type HT No. 104 Freas Oven for operation up to 260° C, and with inside dimensions 12 inches wide by 12 inches deep by 12 inches high, with the addition of a forced air arrangement by means of a centrifugal fan driven by an electric motor supported on the rear wall of the oven. By this means a forced circulation of heated air and consequent withdrawal of moisture-laden air is maintained, materially shortening the time for drying operations. Heating plates are wound for 1500 watts and this oven, therefore, cannot be used on an ordinary lamp socket but must be connected directly to a line of this capacity. With thermometer reading to 300° C, and motor for use on 110-volt, 60-cycle,a.c........ 245.00 468 ae Pon SU a Read cos 7850 7854 7850. Oven, Freas Patent Electric, Type R No. 110, as described on preceding page. Inside dimensions, 14 inches wide by 17 inches deep by 18 inches high, on high iron stand; for operation from room tem- perature to 175° C, by attachment to ordinary lamp socket. With thermometer reading to 200° C, connecting cord and plug. With heating plate wound for 600 watts at 110 volts... 265.00 7851. ditto; but tor220/Volts.c20o Ost aoe. a ot ae amewted nual ce ean es MON eee eRe ale 265.00 7852. Oven, Freas Patent Electric, Type HT No. 114, similar in appearance to No. 7850, but with four control switches at top. Inside dimensions, 14 inches wide by 17 inches deep by 18 inches high, on high iron stand; for operation from room temperature to 260° C. The heating plates are wound for 1500 watts, and, therefore, oven cannot be used on a 6-ampere lamp socket but must be connected directly to a line of this capacity. With thermometer reading to 300° C. For 110 volts............ ; ; Aisle moana k aah ed ; Se ain hee re AS 285.00 7853. ditto: Dutsfor:220 Volts ices foie zac ic goes civ Shweta deena teh Deiat ahumald leh Aes Salah aang ee 285.00 7854. Oven, Freas Patent Electric, Type R No. 140. Inside dimensions, 32 inches wide by 18 inches deep by 22 inches high, without central column, on high iron stand; for operation from room temperature to 175° C. Because of its size, the heating plates must be wound for 1500 watts, and this oven cannot, therefore, be used on an ordinary lamp socket but must be connected directly to a line of this capacity. With thermometer reading to 300°C. For 110 volts.................. 400.00 7855. - g 8150 8151 8152 8154 8155 8155 Front view Back view TRANSFER PIPETTES. These have recently been re-designed as to shape and dimensions and time of outflow, and we endeavor by frequent control to keep the limit of error of total capacity within the toler- ances printed on page 486. As these pipettes, even in the smallest capacities, are provided with a slight bulb in{the tube, they are not always convenient for bacteriological and serological work, for which purposes we list specially designed pipettes on pages 489 and 490. 8150. Pipettes, Transfer, with bulb in middle of tube. To. deliver; ‘Mle sevsecemcere esas ee 1 2 3 4 5 10 12.5 Total length,mm................. 325 825 350 375 400 450 500 EACH co se nosh et OL 18 18 -18 18 18 22 .24 To. deliver; Mle-.ca8 cc hee he eee S 15 20 25 50 15 100 200 Total length,mm................. 500 500 510 520 540 560 580 ae ices sise ak Sistecar tava aoa inaeecenes -28 32 32 -42 .50 .55 -76 10% discount in carton containing 12. 20% discount in carton containing 144. 8151. ditto, but without graduation, i. e., for calibration in the laboratory. Suitable for capacity, ml........... 1 2 5 10 25 50 100 | OEY (a ea ee ee ae ne A een 10 10 10 15 25 35 -50 10% discount in carton containing 12. 20% in carton containing 144. 8152. Pipettes, Transfer, with bulb low on tube. Tosdeliveremls sic. cet peu es Ape ota hee es 5 10 25 50 100 Total length MMs... xin, t eae a sirstesnaeimssliae a gh a han Gaes 300 315 335 345 360 Ba Chesed oe oh ag oe ae ee a ae deee satan Ante Ree eee he “ 18 22 35 40 » 65 10% discount in carton containing 12. 20% discount in carton containing 144. CERTIFIED TRANSFER PIPETTES. Pipettes with unofficial certificate are not always in accordance with certain minor specifications of the Bureau of Standards which do not, in our judgment, interfere with practical use and, while the errors shown on such unofficial certificates will usually be found within the Bureau of Standards’ tolerances, it is not to be understood that pipettes with unofficial certificates will always pass the Bureau of Standards’ certification. The unofficial certificate is particularly valuable as a check where re-calibration is to be undertaken in the laboratory. ; Pipettes tested by the Bureau of Standards and engraved with official mark of certification are, of course, within the tolerances established by the Bureau and otherwise in exact accordance with the Bureau of Standards specifications for shape, dimensions and perfection of workmanship. For the Bureau of Standards’ tolerances for transfer pipettes, see page 486. 8154. Pipettes, Transfer, Certified, with unofficial certificate. To deliver, ml........ 1 2 3 5 10 15 20 25 50 100 200 Total length, mm..... 825 325 350 400 450 500 500 510 520 540 = 580 Bah cies eanus rete aun ek -90 90 1.00 1.05 1.10 1.30 1.40 1.70 2.00 2.70 4.00 8155. ditto, but tested by the Bureau of Standards and engraved with official mark of certification. To deliver, ml........ ‘ 1 2 3 5 10 15 20 25 50 100 200 Baehiccsiak ess eee 1.70 1.80 1.90 2.00 2.10 2.20 2.30 2.60 3.20 3.70 5.00 487 A RCT Ae eR H. T H O M A 5 Gc ©O M P A N Y =e] a pereass — (al : Me Na Vel bene! 33} (tc 9 iso ag ao 0° Za es ‘ oO eee Et _o o — & bes = = : é Le =] | A a = : E ‘ = [2 [2 ‘ Lo = = | E -< rl e = cE) =) Ce =e = = |_1| 4) = LB | —8 I Es F =. = ike ks =9 = ls Ee = = = | MB | E | E40) —10 | | | 7 | | i \\ t jj } yoy / V | | | : U uy 8160 8162 8163—Front view 8163—Back view MEASURING PIPETTES. These have been recently re-designed as to shape and dimensions and time of outflow, and we endeavor by frequent control to keep the limit of error of partial and total capacity within the tolerances printed on page 486. 8160. Pipettes, Measuring, so-called Mohr Pipettes. To deliver, ml. ceccce ee oes d ; : teed 120 1 1 2 2 Graduation interval, ml............... Reet. FOO 1/10 1/100 1/10 1/20 Total length,mm........... pian Gye arnt cee nantes . 805 330 385 355 355 Wachee oe hes ce hicty ee ha ia A gie mut nebee Ons -45 .40 45 45 50 ‘To. deliversml ss vs:54 oso noo olka Aa ee am 5 5 10 10 25 50 Graduation interval, ml............. pein reve Lf TO 1/20 1/10 1/20 1/10 1/5 Total length, mm. «2.40 6c..s 40044040 0010s 380 405 430 455 490 600 ACH ys 6.0 hear ane Wah tcsactins ceo oie ota ten cee 50 55 55 .65 -70 1.10 10% discount in carton containing 12. 20% discount in carton containing 144. CERTIFIED MEASURING PIPETTES. Pipettes with unofficial certificates are not always in accordance with certain minor specifications of the Bureau of Standards which do not, in our judgment, interfere with practical use and, while the errors shown on such unofficial certificates will usually be found within the Bureau of Stand- ards’ tolerances, it is not to be understood that pipettes with unofficial certificates will always pass the Bureau of Standards certification. The unofficial certificate is particularly valuable as a check where re-calibration is to be undertaken in the laboratory. Pipettes with the Bureau of Standards certificates are, of course, within the tolerances established by the Bureau and otherwise in exact accordance with the Bureau of Standards’ specifications for shape, dimensions and perfection of workmanship. For the Bureau of Standards’ tolerances for measuring pipettes, see page 486. 8162. Pipettes, Measuring, Certified, with unofficial certificate. To deliver:smlixiai 3.0.5 Bas a eke ee ee, 1 1 2 5 10 25 Graduation interval, m]................... 1/100 io a ay iy to Total length,mm.................... =e 885 855 355 380 430 490 aches ea neste hes oie aera 1.60 1.30 1.80 2.20 2.60 3.00 8163. ditto, but with Bureau of Standards certificate. Tovdeliverjcmlsce weg kris ee 8 Phy oats, Sree A 1 i 2 5 10 25 Graduation interval, ml................... 1/100 to 10 to te to RCW eas eae gree cette eee ch 2 epee ee ep eter 1.90 1.50 2.00 2.40 2.80 3.30 Note—The extra price charged for B. of S. certification includes the Bureau fee, the cost of transportation to and from the Bureau, breakage loss in both transportation and testing, the loss for rejected pieces, and a reasonable profit on these expenses, which become a part of our merchandise cost when the item is placed in our stock. 488 A R T H U _ R H. T H O M A S Cc O M P A N Y ] 1] 7 ee | | | nm ra i 3 Ey F ' |: i : : : : C a a e a | i 3 =z a z 4 i. ; = i ’ ; ol ; 8 | 8 || = mi) a L a — ES 84 A | Es Es Fe = | E ti Hy -2| 2 Ea| al E - _ EI ate i 3 [3 = IE t E| E Ly Al Hy Es FI E E = ry Fi L5| = = L : EY LE I A HEL - F | ES = 4 7| 2 | en as = | Ea Si L a i. E Fal F 3 | Esl fis ry 3 = = [4 |e | \ \ On1 smi \ a L0mi J 8168 8170 8172 8169, 8171, 8173 8180 SEROLOGICAL PIPETTES. These pipettes have been specially designed for serological purposes, with special reference to use in Wassermann and other complement fixation tests. In such work, involving the use of pipettes ca'ibrated to the extreme tip, it is more convenient to blow out the last drop than to wipe off as specified in the Bureau of Standards’ methods for adjustment of volume. For the purpose of ready identi- fication we mark all pipettes adjusted by blowing out the last drop with two etched bands as shown in illustration. These pipettes are all adjusted within the tolerances printed on page 486 for Measuring Pipettes. Safety Filling Attachment can be supplied with any of these pipettes for handling infectious material to avoid danger of mouth suction. It consists of a glass cap with a tubulation which is withdrawn with finger or thumb closing the opening, thus filling the pipette. Exact control of the discharge is accomplished by removal of finger from the opening. As this attachment must be fitted to the individual pipette, it is not sold separately. 8168. Pipettes, Serological, calibrated to the extreme tip. To deliver, ml..2. 2202 24 ncaee ares taone ns iy 2/10 1 1 5 10 Graduation interval, ml................... 1/100 ~=—1/100 zy ~—«i1/100 to a Total length,mm........................ 300 300 300 325 300 325 Bah cecc he ee ete chs ee ‘ -45 50 40 -45 .50 -55 8169. ditto, with safety filling attachment........... 70 75 -65 -70 75 .80 8170. Pipette, Mill-r, designed for use in Wassermann and similar technique where } ml is used as the unit of volume. Calibrated to extreme tip, and with zero mark 100 mm from the top. To deliver 1 40 ml, graduated in ¢;ths, with number at each % ml. Totallength300mm................... ‘ 8171. ditto, with safety filling attachment.. Poet sacra Vd eccatli te metic arhaclet is caer, ced Nate tt at Nee ee Ook .65 8172. Pipettes, Kolmer. These pipettes are not calibrated to the extreme tip. Tor delivers tM les wen sacevtewn cine eae ar cate een Ok 2/10 1 1 5 10 Graduation interval, ml.......................... 1/100 zo —«i1/100 ty 3 Total length,mm........................ ens 330 300 300 325 350 Te a AEA ORES RE Oe OEE oe 50 45 45 50 -50 8173. ditto, with safety filling attachment. wee ee 15 -70 70 75 15 BACTERIOLOGICAL PIPETTES. For use in eee te technique the usual transfer and measur- ing pipettes are often found to be inconvenient as to shape and dimensions. The following pipettes have, there- fore, been specially designed for bacteriological work. 8180. Pipettes, Bacteriological, without bulb, as used in bacteriological examination of water, milk, etc. Geli VO Ts sk see Nese eng cel 9) wind cepcreiccus Sols storia Nee mer rase Rw aE wt DAR eee Total length, PULTVN oo sc aed ce CN Rr Seth Sores pe Ren dy teas Ted Noo nN ite ie ay 275 300 325 14.18.22 The Pipettes listed on this page are all subject to a discount of 10% in cartons containing 12, and to a discount of 20% in cartons containing 144. 489 AO OR. 9 (OH (Us oR H’. T H O M A _ S§S CO MP A NY | 1] E Hl a) | = ca si Rea ~ Mi "| [Om Ment : = iB s a 20'¢] 20°e, | 5 ; i | a ies AKT Prk ¥ i ‘ Lyi wi iy - 1 2 10 ae 1} ial lial , : Bl L os Le) = S A (\ = = - -— , 4 gi ‘r) = =. a | 4 | | Le a 2 Ls EJ Eg 5 i | er a a As i 3 F = 20 3 y | | ss og = : i | = z ag 05 = E = b : a | uw “ E 4 i 8 = fi 5 | ed a Hoy ml | H = 20° i c 1 Hei Lo | ae Ps ‘ 20° ‘a | ¢ e | || | yo oY | ees 8182 8184 8190 8191 8192 BACTERIOLOGICAL PIPETTES (Continued) 8182. Pipettes, Bacteriological, Stokes, specially designed for bacteriological examination of water and differing from No. 8180 in both shape and dimensions. These pipettes are intended for use with rubber bulb for filling and discharge. TR OTGelIVER sitll ct ae cata ls oon syste sack tomate alAbates Sanaa Antal ce trcad Cte aps anat oy Syrah kates rece iusto 1 10 Total lenothecminiy oc 35 «hic ake ccsn boaveaguud, atcane hh ina ALA oe een ina conti iba caer eee ee 170 334 Ba Chae sire cee eee te ee ey cea tates a IR NA ch Can pers Wh rerataaen Saari aces Rue eae ce 20 .30 10% discount in carton containing 12. 20% discount in carton containing 144. 8184. Pipettes, Bacteriological, Model of the Hygienic Laboratory, U. S. Public Health Service, and specially designed for use in water analysis. The 2-ml pipette is graduated from 0 to 1 ml in y5ths and is ungraduated from 1-ml mark to 2 ml. The 10-ml pipette is graduated from 0 to 10 ml in single ml. The 11-ml pipette has a mark at 0, 10 and 11 ml only. POL ELIVER In tiene ence naga las mM ge, itcara Psrirach a a au ouch ah arhree any AA Real Et eel aatitaney® 2 10 11 Total lengthemims oh ole rave ends reek ca Ny pee a eesk Ge bad Sonia Mau een nen eCe eA 350 375 400 GACH eho Gece eee sy Rac cn aE RR ee ehh camer any tease arte cay My Sera 32. 32 «232 10% discount in carton containing 12. 20% discount in carton containing 144. IMMUNITY UNIT PIPETTES, Model of the Hygienic Laboratory of the U. S. Public Health Service, for determination of the immunity unit in the standardization of diphtheria antitoxin in connection with No. 4416 Immunity Unit Cylinders, described in Hygienic Laboratory Bulletin No. 21. The volume is adjusted within the tolerances given on page 486 for our certified pipettes, but these pipettes are not regularly furnished with certificates. It should be noted that Pipettes Nos. 8190 and 8191 are graduated to deliver, whereas No. 8192 is graduated to contain. In the graduation of these pipettes, the volume is adjusted by blowing out the last drop. 8190. Pipette, Immunity Unit. For ready identification, this pipette is supplied with two etched bands near the top: ‘TotalJength 300 mm. ‘To deliver Lomb. icc 2 2 cults asin hee eg be ana ead eee -80 8191. Pipettes, Immunity Unit, so-called “Ehrlich” pipettes. Graduated in 1/100 ml between the capacities indicated. Mo delivercimle secs oo eo eae a ee eons Wenee Bain er Ge aie, .01 tol 0.7 to 2 1.5 to 3 MotalsleneGhesraime bs .qinentus urhehd Reacusae ety ne tein Eh eds wade noe 350 400 425 ee Hacc oes ek oe fees eS A ro Re ere Rae Oe hens 1.25 2.00 2.00 8192. Pipettes, Immunity Unit, as above illustrated and described. To. contains: Mla. seks Fg eed 1 2 3 4 5 6 10 Total length,mm.................. 800 300. 300 300 320 340 375 Bache: odin oe aie ei areeen saa Bes .60 -60 .60 -60 -70 75 -90 490 A R T H U R H. T H O M A _ SS Cc O M P A N_ Y f a | ® f l & pr B f mi z ka poe 8 } g re & 2 = Le | er {15 | Fe 4 al M | : | 4, Ea fr | a : A | : = : | ‘4 L_| ; ei 8 6 3 S _ F : z fs a 7 i P| 4 [| z | i +24 s = 8 / 8 i} \ = Af] | x % = = g No. 126 g eis {4 =f EA 3 Sut 5 a \ \ | : | | rp ! | (0| FS \ 8200 8201 8204 8205 8206 PIPETTES AND BURETTE FOR THE NEWER METHODS OF BLOOD AND URINE CHEMISTRY. The wide adoption of the newer methods of blood and urine chemistry, as described by Folin, Van Slyke, Lewis- Benedict, and others, has developed new uses for the so-called Ostwald Pipettes, originally described by that author for calibration purposes. These pipettes differ from the regular transfer pipettes in shape, dimensions and accuracy to which the volume is adjusted. Our Ostwald-Folin pipettes are adjusted within a tolerance of + 35 of 1% when the last drop is blown out. It should be noted that No. 8200 Pipette is graduated to deliver and that No. 8201 is graduated to contain. These Ostwald-Folin Pipettes are used in Folin’s method for the determination of total nitrogen, urea and ammonia in urine; Van Slyke’s method for the determination of carbon dioxide and carbonates in the blood and other solutions, and for the determination of sugar in the blood by the Lewis-Benedict method, in addition to a great variety of other uses. 7 The Folin-Wu pipette for use in the preparation of protein-free blood filtrates is graduated to within the tolerances established for our regular transfer pipettes and as given on page 486. 8200. Pipettes, Ostwald-Folin, as above described. TOsdelivier. talec omy aw ersba Peewee incon tn aera aint a ate 1 2, 3 5 10 Totallemoth simmers: te wal da ce eee A ater ON ot a a es 275 275 300 325 325 BO Drees cee ete heed RSE LEECH teh hE ey G .80 85 -90 1.10 1.30 8201. ditto, but graduated to contain, ml....................... 1 2 3 5 10 ACH oe ae) tacts cack aman nts sue el os ae Gaal Ohne -cumeet ante -80 85 -90 1.10 1.30 8202. ditto, but without graduation or adjustment for volume, 7. e., for calibration in the laboratory. Suitable for capacities, ml..................2....000. 1 2 3 5 10 ACH Ree eee ee Deere Macarena -40 45 -50 -60 -70 8204. Pipette, Folin and Wu, 15-ml capacity, graduated from long tip in 1 ml divisions, for use in the preparation of protein-free blood filtrates. See O. Folin and H. Wu, ‘‘A System of Blood Analysis,” Journal of Biological Chemistry, MOY; VOLO scoot io soins. is, 6 eis coh Ph A BAD ace cance leks dean Gia auang Wises elena 50 8205. Burette, Sugar Titration, Folin, as used in the titration of undiluted sugar urine by the drop method. Delivers 25 to 30 drops per ml. See Folin and McEllroy, “‘A Qualitative Test and a Quantitative Test for Sugar in Urine,” The Journal of Biological Chemistry, March, 1918. Capacity 5 ml, gradua- tion interval 0.02 ml; with glass stopcock. These burettes can be read to 0.01 ml.......... 4.75 INJECTING AND MEASURING PIPETTE, designed for use in the U.S. P. method for the physiologic assay of digitalis and other drugs. The transfer of small amounts of fluid from a measuring pipette to a glass container and then to an injecting pipette is avoided by the use of this combination pipette, which serves both for the measuring and injecting of the drug in less time and without loss of fluid. ; The lower end of the pipette is drawn out to a fine sharp point with an opening in the side somewhat above the point. This design permits the easy introduction of the pipette into the anterior lymph sac of the frog, and the position of the opening prevents it from being clogged with tissue. As designed by Dr. G. B. Roth, Hygienic Laboratory, U.S. Public Health Service, and described in the Journal of Laboratory and Clinical Medicine, Vol. IV, No. 6, March, 1919. 8206. Pipette, Injecting and Measuring, Roth, as above described. To deliver 1 ml, graduated in 1/100ths. .80 The Pipettes and Burette listed on this page are all subject to a discount of 10% in cartons containing 12, and to a discount of 20% in cartons containing 144. 491 oR eR H. TT H O M A 5S Cc O M P A N Y 8210 8210. 8211. 8212. 8214. 8216. 4102. 8218. 8219. 8220. 8212 Showing arrangement of slot in stopcock plug which admits air to the bulb on second turn or half-way. ed ay 8212 8214 8216 4102 8218 8219 PIPETTES DESIGNED FOR SPECIFIC USES. Pipette, Automatic, 1 ml, with rubber bulb. Very convenient for rapid automatic delivery of 1 ml CH Arges ick. ree trea netotee ed ctee in esata ek nhc ths Siuna ter peat rate reer eane este Marra aracteantae rd 1.30 Pipettes, Automatic, with three-way stopcock. Tovdelivers mils ots sine Sicsiycieucraect arn ce eos Aerated mane ene ica tie 10 25 50 100 ahi eee ives Resouces ene ok erate ma cus ee atest iar 2.80 3.60 4.50 5.00 Pipettes, Lowy Automatic. The liquid is drawn up until it just passes the graduation mark. The stopper is then rotated through an arc of 90° cutting off the excess liquid from the exact measured volume drawn into the pipette. Another rotation of the stopper through a 90° arc permits the delivery of the measured volume of liquid. Any excess liquid drawn into the pipette is returned by revolving the stopper to its original position. Tovdeliver).ml.....25.. 3c. ys Woes eee cai 1 5 10 25 50 100 Baehis cc.cc tus pakionunantn ui wiouensen cutee ea een 2.75 3.00 3.20 3.80 4.00 4.50 Pipettes, Calibrating, with two marks. These are in the main as originally devised by Ostwald, with some slight changes in shape and dimensions as suggested by competent users. OPO eli vere Mil vacgerte crate isn fy oes es sabia» ON erate ame Sie aaht catered Ge oer Ree nete c 2 5 BACT eo oe Sel ect caus Sete ei ch INC 2 SHS Tea to rt dc er vegas ep vet ah 1.25 1.35 Pipette, Calibrating, to deliver 2 ml; graduated for #5 ml in 1/50ths above and below both zero MYLES ssa Ses Rae aT ag ee ate Pa aR, Saeki uae NaI A hr fal lie RE aha Tani Teno i ane UN 1.80 Pipette, Capillary, Breed and Brew. Without bulb, capacity 0.01 ml, calibrated in accordance with the specifications of the authors to deliver 0.01 ml of milk, sp. gr. 1.032 at 21° C. See Breed and Brew, Counting Bacteria by Means of the Microscope, Technical Bulletin No. 49, New York Agricultural Experiment Station, and Standard Methods for the Bacterial Examination of Milk, A.P.H.A., 8rd Ed., LD coc covtse es Sop hats aa EN ASN GARI ods Oe HPAES De IG BENS TS Iie sa TK see soap ee te an trang gas Rah 1.20 Pipette, Collecting, Banta, 200 mm long, with glass bulb 35-mm diameter, and with 50-ml rubber bulb. Capacity of the rubber bulb and the large mouth of the pipette facilitates catching by sudden suction small animals too quick to be taken in a small gauze net. The capacity of the glass bulb permits examination of the sucked in water. See Science, July 17th, 1914, A New Form of Collecting Pipette Artur Mi BOM eo os asc Sates ahigh toons tee Ses a oe asec eta? day aiken hoes eee OT 60 Pipette, Cottonseed Oil, graduated to deliver 7.05 grams of prime crude vottonseed oil at 20° C in from 1v to 15 seconds, in accordance with the specifications of the American Oil Chemists’ Society. While designed especially for cottonseed oil, this pipette is also used for other vegetable oils, such as peanut, cocoanut, sesame, soya, rape-seed, etc... 0.6... eee cee eee 50 Pipette, Dilution, Freas, for convenient delivery of eleven successive charges of 9 ml each of. sterile water, as required in filling dilution blanks in milk analysis. Graduation interval 9 ml, total capacity 99 ml. With glass bell over tube to protect the outflow from air contamination. 9.00 492 A R T H U _ R H. T H OF M AS Cc O M P A N _ Y SUE ETRE EEA See See AKT co. Jor | Sucrose 52.096 Grammes} fod LWW y 8222 8223 (Straight) (Curved) 8225 8226 8227 8230 8231 8240 8242 8224 8224 8222. Pipette, Dropping, 4 inches long, with straight tip and bulb of red non-blooming rubber of superior quality. Not to be confused with the ordinary medicine dropper. Perdozen....................-.-- 35 10% discount in carton containing 144. 8223. ditto, but with curved tip. Perdozen..........0...0 0.00. c ccc ete tee eee eens .35 10% discount in carton containing 144. 8224. Pipette, Dropping, with a bulb in the center of the glass pipette which prevents the liquid from entering the rubber bulb. Length 32 inches, with a 3-ml red rubber bulb. SL VTCR a canes as Sol Saeed pat coast coe ved a a dean che bes aR NE IEEE Ca Aelia oan cee Straight Curved IE RCTs arate tater te aes eal sere ce are Saad ak heme ite i tt ln AE AS Tech ocean Rar tent N aN ea -10 -10 10% discount in carton containing 12. 8225. Pipette, Dropping, with glass tube 3} inches long of large bore and with rubber bulb, suitable for removing large pieces of sediment, small embryos, etc. Each................. 00.0.0. c cee e cece eee 10 Per dozens, one ed eles een gabon eek -70 8226. Pipette, Dropping, straight, without bulb. Teen gthy AM ees u cee ner chee -o algae un canes hele Men Raa Mb evandiene ettes fone 200 300 WA Ee es each he ee ba ates Pe eae aie eel Aili cas Sa ce iA erica ene eles eel aah chee nee aon on To 10 12 10% discount in carton containing 36. , 8227. ditto, but with red rubber bulb of about 3-o0z. capacity. Tse mn SEH SMT eyes toteseecentiess Oirs teak a te doen terosapa g lah ERASED heey ER AVON dire a ec cate ceeieo 200 300 Blaha eek eh eats oss Ne eRe Seek I Sen) sie Pubeaahsa bi Ghee nce ee me 25 -28 10% discount in carton containing 12. 8230. Pipette, Mercury, for taking up drops without danger of same entering the mouth............... .45 8231. Pipette, Mercury, for the convenient handling of small drops of mercury....................... 45 SUGAR PIPETTES. The Spencer-Crampton Sucrose Pipette, devised independently by C.A. Crampton and G.L. Spencer at about the same time, is so graduated that if filled with juice to the mark corresponding with the observed (uncorrected) degree Brix, it will deliver two normal weights of the liquid, i.e., a total of 52.096 grams on the basis of the Mohr liter, or a total of 52 grams on the basis of the true or metric liter. It is graduated for a range of density from 5° to 25° Brix in ygths. These pipettes are made in accordance with the author’s specifications as to shape and dimensions. : The Spencer Glucose Pipette is on the same principle as the Sucrose Pipette, but graduated to deliver 50 ml if filled with juice to the mark corresponding to the observed (uncorrected) degree Brix. See ‘A Handbook for Cane-sugar Manufacturers and their Chemists,” by Dr. G. L. Spencer. 8240. Pipette, Sucrose, Spencer-Crampton, to deliver 52.096 ml. Graduated in Brix scale from 5° to 25° in 1 Bc ae des peer ae es a nents ete erana se A ty sue a 2.00 8241. ditto: butsto: deliver-52.mlty cco cosh ak hs tere ee nas Sema seein Se ee 2.00 8242. Pipette, Glucose, Spencer. To deliver 50 ml. Graduated in Brix scale from 5° to 25° in 7gths.... 1.80 493 AS SRS Ts te) W oR H. TH Oo CMe MASS Cc O M P A N_ Y 8250. 8251. 8252. 8253. 8254. 8255. 8256. 8260. 8262. 8263. 8264. 8265. 8255, 8256 3264 Pipette Boxes, cylindrical, of polished copper, with tightly fitting lid one-third the total length of the box, permitting pipettes to be easily removed when the lid is taken off. Diameters In CheSe he sotst its saan eet ci crbe then sh namie cucceyy acm hnnonn ae) aweer deh Mane. een na et 24 2 Men eth tn Chestian core tl aes Guinan ain Soiale alah emer abo FA ok. h ee oe vie ote es 10 16 aC Diese ey Nila cA naa a aR PE Get h rsasto ed Oe oe Rte aaa rrn arpa aie ear terre rcs 2.50 2.90 ditto; butsof sheet irone~ qin io va non week eater ee oimatyae o atamenn anes elnino oul arcoe castle 1.25 1.80 Pipette Boxes, rectangular form, of polished copper, for sterilizing pipettes in bacteriological work. SIZES ACHES ai a ee eieanea AAaree carer peor: aot toy waeery Mister meme leet a adh 13x 24x10 13x23}x16 AC Higley woera osteseea orate aA ae aoe Aiea Cub da ated anidyan feat en oincpeas 3.60 4.00 ditto; but: of sheet aroncscer ¢ cccAx cue ete meena peas eee He Areas ornGen eal 1.50 2.50 Pipette Box, rectangular, of nickel-plated brass with asbestos lining, with lid and removable end as shown in illustration. Convenient for transportation purposes. Dimensions 2 inches high x 4 inches Widesxsl Gumches:1OMnGNs 42 5.8 atk eee Aumann ee mime Reker eek eet on lata eae, ocishn teibats aan wean ee 12.50 Pipette Box, Portable, rectangular form, of polished copper, with convenient handle. Dimensions 1% inches high x 34 inches wide x 24 inches long. ....... 2... cece Bien 8.25 ditto; butiol galvanized iron s:.2.4:.. sesees-ceee ss tcnaw Weaiey eee aoa, Oawee Rare oh ae epee aac 6.60 Pipette Rack, of copper nickel plated, with removable bottom shelf of glass to protect tips of pipettes. Capacity, LOM PNPELEES Ge st Cie saacitnckec. 1 hog rae. adit oceta aes ease a a ane Bou Oe UA, Pasadiig hle Tole be 3.50 Pipette: Rest; of porcelain; 75: x:650mm yy.e3 a otha ade ee geek Laas eis Say eae thm aes eee e's .65 Pipette Rest, of aluminum, with twelve numbered depressions for pipettes in horizontal position.... 2.00 Pipette Support, Revolving, of polished hardwood, with eight 17-mm and four 7-mm holes.......... 2.50 Pipette Support, Revolving. The perforated decks are of polished copper ene on metallic ae support; with thirty-two 10-mm, twenty-four 12-mm and eight 15-mm holes. 3 . 5.00 494 8270 8271 8274 . 8275 8270. Plates, Glass, Circular, plain, with edges as cut, i. é., not ground. Diametersin chesictelo.stiantcty tae mt eA Ban re ee eee oe 3 4 5 6 _ Per OZONE ize es Gg Pa Og cuca htt ae DRUh iene ede 72 .96 1.50 3.24 8271. ditto, but with one side ground. Each........................... 10 12 -20 32 8272. Plates, Glass, Circular, with edges slightly ground and hole in center to admit stirring rod. Convenient for use as covers. WDiametersinches, Packs ccc sss erento eee ok areas See ee ee ee 3 4 BEACH a sah tiee ae cre ee alee een Octane Weeden en serra tas eri dey Shei anata Nee Betsy .30 -40 _ 10% discount in packages of 12. 8273. ditto, but with hole at one edge. Diameter sin chess isc asave neo hte Aacaeed tn ee are a eev ren deb “ares mwa ob ee 3 4 BRC gy he ce cerns cee nO esp pa eee etre Ne Dee Ad) teh Sete aac Cb Ls .30 -40 10% discount in packages of 12. 8274. Plates, Glass, Square, plain, with edges as cut, i. e., not ground. DIZERINCHES 6a eke bes Biaveny, oo oan3 anu lynn nian kona etree homie automa 3 4 5 6 THAN eae ecseta crt aie tat fa tienda teen eran te ao Ponte gia 10 12 14 15 10% discount in packages of 12. 8275. ditto, but with one side ground. NIZE AN CHES aoa ce sarrrge hence canvas opal Mby basta zaiigtcnde Sata aces el GUAM oA ee eceioerte 3 4 6 ACI rye ee ore preety cet aki eae Coppa As AEM cA Cul act tee ae, -20 -26 .30 10% discount in packages of 12. 8286 8276, 8277 8284 8285 8288 8276. Plates, Heavy Plate Glass, Square, with edges as cut, 7. e., not ground but with one side ground. SIZE; LIN CNOS ie ans escheat dav erie ease Sea tere eeaasinaeesasse RAG eetror hi det eee arias 6 8 10 12 AOI 2 ek fre on, arsine cnr aera a eid cs PR tae arate pe MS Deh a cane eee CI 50 .60 1.60 2.00 10% discount in packages of 12. 8277. ditto, but with edges ground. Each......................0.00055 -60 70 1.70 2.10 10% discount in packages of 12. 8280. Plates, Blue Glass, so-called “cobalt” glass, for observing the potassium flame; with ground edges. This glass is pot glass and not flashed glass, which latter is totally unsuited for the purpose intended. Sizesin ches? hrs dco ease Gs Case Pa eae a te Re 2x2 2x3 3x3 4x4 BOM adore coe ernie eee tc a teeth Won arrcket alcoy Sha cea Som teats ts aus Anos lar ge 14 16 .20 -26 10% discount in packages of 12. 8282. Plates, Corning Daylite Glass, as used in Colorimeter and Micro Lamps. SIZOs TA eae sees ee eee seen eoshig re Se nite nce Sere Wee RE SAAR on ree eared tae aii h Guo Srtamige 55x55 82x 82 RTDs acdc a sae eco eS oe RS ne MTOR fers EON ad oa aie aetna Aer lap A Been ns AACN la 2.00 3.50 8284. Plate, Earthenware, White, so-called “‘tile,”’ glazed on one side only, size 6 x 6 inches............ -40 8285. dittosbub: blacks ie. eies ce ONC ais ais Meat G rest a mialy Gnmoslicus cmpeiag ticciay neva nmdn mani wtsunh muepansve Sua ay 50 3 ; lazed Porcelain, beveled at an angle of 60°, and perforated for use in funnels as filter discs. ee eee ies TAIMG ethers A aominpoeuceanenti CS eth SRR Sars neg 22: 25 30 388 50 60 Thickness; mms cvcwiess Gali a are ie Pe howe chy nears 2 3 4 4 4 4 Diameter-of holes, mms. 5 2:ecanr ah as omsee kee ae on 8 tA ks 1 Wa Chie oie ae ed ec oan Re bee Ie a aa eds B2E 28S 36% 4G: ab 10% discount in carton containing 12. in, f lor reactions. Glazed, with twelve concavities. fee Baa ea eee ener een irae 110x90 160 x 125 Each .84 1.14 Ae URS A 250. eR H. T HH -O M A 395 Cc O M P A N Y - ate 8290 8291 8292, 8293 8294 8295 8290. Plates, Porcelain, flat surface, glazed with the exception of the bottom surface. Very convenient for colorimetry, titrations and other purposes requiring a white background. Approximately 7 mm thick. SIZeP MM: ie ea ce ea eS 100x100 152x152 1387x175 126x203 203x305 Hache: oto. anor eee Ni eke hoes 84 1.80 1.80 2.40 7.20 8291. Plates, Porous, of unglazed S. C. P. porcelain, for drying crystals and precipitates. This ware is par- ticularly recommended for its unusual absorption property. Diameter 10 inches......... 25 10% discount in packages containing 12. 8292. Plates, Porous, of unglazed porcelain, for drying crystals and precipitates. SUZ Oe MY yeh eae ees cul Ta armen Ne iate ena olla SRO nd BRA carat earayne _150 x 150 200 x 200 SFA 2h telesales itl eh a eid Rage NLA a lea ce Rr ener -50 1.00 8293. ditto, but of Coors unglazed porcelain, 6 mm thick. SEZ IVT ea ik oot ee re PR ia Banh baa: Foes yal eh ail ats Annee in ame nla ace 300x200 305 x 305 aC hae eh cee Sans ae eer a ea ne rebinn at oe aye Nay RCPS nt ead utp Peon oh Bt 3.30 4.40 8294. Plates, Porous, Circular, of unglazed porcelain. Diameter: MMe e oer Gites, oak Sounds iano Oe en iee PA O 145 175 220 Wachisys os eas es errata ee See et hag eters mul gion 2 ce igs Sis Sane 1.08 1.44 2.40 8295. Plate, Streak, of unglazed porcelain, as used in arsenic tests and by mineralogists. Size 100 x 60 mm, ASTMITA CHUCK cree A et tra Ved nh aN AN ae Bk Nahar Nac ease oat aeT ew Sic te Vo eR an Ue a ea a eneor EN Saget Aue 48 8296. Plates, Opaque Silica, Unglazed, }-inch thick. Preferable to wire gauze for use as heating plates on account of their cleanliness and absolute resistance to corrosion. Will stand extreme changes of temperature without cracking. Sizesinches Aue cin ceie yee rai acm en ah te en a aoa aoe aetna armed wiemmue sil 3x3 4x4 6x6 MC Mn as Bese ors teats A sts hang cute eee Tie Ted Seg es eben Rene en Cs ae dy eat ene Renate .50 88 1.98 8297. Plates, Opaque Silica, Glazed, }-inch thick. : SIZ ORM CHES sai ascarena ator event eianc'A niet Wares neta ds cake emonaea Sean aone nein 8x3 4x4 6x6 ah ise eas Wee caine ee astern sens Maris oti» Saas Mine amet eg ent aan cert nc O tk 1.98 3.52 7.92 8298. Plates, Transparent Silica, ~s-inch thick. These plates have a smooth fused surface, and are not ground for optical work. SIZE AMCHES ss i atin Sete ene thee ne Gl Santee aE eeu Beene cay ceaants ees co oes nae Le ee 3x3 4x4 ACH Gyles icc asteat ans Sate dete i paseeas id seek A ESE TNT mn Saou Se PAM RA Ee cep eee ek tp Stee 5.85 10.40 PLATINUM WARE Our stock of platinum ware for immediate delivery is confined to the shapes and sizes listed below. All other shapes and sizes are handled on special order, about one week’s time being mostly necessary for delivery. As platinum ware is sold by weight, we print the approximate weight of each piece. Prices are not printed because of constant fluctuation. Our per gram prices for foil, wire and hammered shapes are kept in accordance with market change and are quoted on request. Precautions to be Observed in Using Platinum Ware Do not heat “unknown” substances in platinum vessels. ; Always keep the platinum ware bright and clean. For this purpose use fine sea sand, with rounded grains and free from grit, a3 a polishing powder. This removes most impurities, and polishes without serious loss. Apply the sand with the finger. To fuse a little potassium bisulphate in the dish is a good method for cleaning the inside of badly tarnished crucibles. The bisulphate is poured out of the crucible while fluid and the crucible then cleaned with water and sand. Never heat the platinum crucible or dish in contact with iron or metals other than platinum, nor let hot platinum be placed in contact with foreign metals. Use nothing but pipeclay, quartz, or platinum triangles, and platinum-shoed tongs. Do not fuse metals in a platinum crucible, nor heat in the crucible salts of the_easily reducible metals, particularly salts of lead, silver, arsenic, antimony, copper, bismuth, tin, etc. Do not heat phosphides nor the sulphides of the metals in platinum crucibles. Sulphur alone has no action. Phosphorus attacks platinum. Phosphates, under reducing conditions, may form phosphides and phosphorus, which attack the metal. ss Alkaline carbonates do not attack platinum very much, but the attack by caustic alkalies and alkaline earths is serious—particularly lithium and barium oxides. Hence, alkaline nitrates, nitrites, hydroxides, and cyanides should not be heated in contact with platinum, if it can be avoided. Do not use aqua regia or free chlorine in contact with platinum. Watch for reactions in which chlorine might be liberated. For instance, hydrochloric acid and oxidizing agents. Direct contact of platinum with burning charcoal, coal, or coke must be avoided. The platinum becomes brittle and liable to frac- ture if this precaution is neglected. Never permit a smoky flame to be used in contact with platinum, since a gray film is formed on platinum in mild cases, and the platinum is quite disintegrated in bad cases. For a similar reeson, do not let the inner cone of a Bunsen flame come in contact with the metal. Meker burners should be preferred. Platinum is easily bent, and care must be taken not to bend the crucible in handling, gripping with tongs, ete. 8300. Platinum Foil. This is carried in stock 8 inches wide and can be furnished in any length up to 24 inches. Light Medium Heavy THICKNESS: sM MNES. ¢ eats en nate hue ae Senter a tne ae ae hoes re ah a, .03 .04 0 “ TUSKOO (HRP ES NCW RCA RU RRSO SEES eee tS Sea VERE ET even ties ee Te .00118 .00157 .00196 Approximate weight per square inch, grams........................ 353 530 -705 8302. Platinum Wire, special for calorimetry, exactly #5 mm in diameter. 496 8306 8307 8308 8309 8303. Platinum Wire. Platinum loops for chemical laboratory work are usually made of No. 26 Wire, as are platinum inoculating needles for bacteriological work. For a stiff inoculating needle we recom- mend No. 24. All weights given are approximate. BSS i BAUger te iiatsns tee nut oh eote 12 14 16 18 20 22 24 Diameter, inches............ eee .080 .064 .050 .040 .031 .025 .020 i MMI 4 o| de ee aks 2.021 1.625 1.269 1.015 -787 .634 .507 Weight per foot, grams........... 21227 13.62 8.31 5.36 3.20 2.08 1.33 BeQS sagen: skis oda Monee 25 26 27 28 30 32 36 Diameter, inches................. -017 -015 .014 .012 .010 -008 .005 ey NOTA = AI SL na be 431 880 355 304 .253 .203 .126 Weight per foot, grams............ “yO 7 75 -65 48 33 AS -086 8305. Platinum Anode, height 125 mm, diameter of spiral 15 mm, approximate weight 8-10 grams. 8307. Platinum Anode, made of heavy wire with special elongated loop. Weight approximately 4.5 grams. Intended specially for use with No. 4786 Braun Electrolytic Outfit. 8308. Platinum Electrode, with closed gauze cylinder. Height 2 inches, diameter 1 inch, of 52 mesh gauze. Approximate weight 10 grams. Care of Electrodes. At the end of electrolysis, the moment the current is turned off, it is advisable to place cathode in a beaker of water without taking time to disconnect. Then dip in alcohol, dry and place on tray. The deposits are hard and firm, eliminating any danger of removal of copper by handling. The electrodes are cleaned by dipping in nitric acid, washing thoroughly and allowing to stand. 8309. Platinum Filter Cones, seamless, with perforations, .020 inches in diameter. Diameter ainches:<. (ace 2dciel ish canes 2s adic Gee aeinle bile Mecsas Ginn d eau tei non eee aad 3 z Approximate weight, grams................ 00.00 cece eee cee eee Sie ks eee 1.0 15 8310. Platinum Crucibles. Covers are always furnished unless otherwise ordered. Capacityaml saci wie eee ae Ace wae ens 10 15 20 25 30 Approximate weight, grams...................... 10 15 20 25 30 8311. Platinum Dishes, withlip. Capacity,ml....................0..0-.0.000. 50. 75 100 Approximate weight; grams) co os ener ee yee ea aA whe AN ed eee 17 25 33 8312. Platinum Sponge, set in ring. For igniting hydrogen, and for similar purposes................ 75 ” 8320 8321 " 8322 8323 8320. Pliers, Steel, with pointed nose. Jaws are flat inside, 5 inches long 8321. Pliers, Steel, with flat nose, 5 inches long......... 0-0... cee ees 8322. Pliers, Steel, with flat nose, side cutting, 8 inches long... 5 ed sake hee ss 8323. Pliers, Steel, with round nose. For bending, etc.; 5 INCHES LONG reid nape. s Gaon erg tee see eee 8324. Pliers, Steel, end cutting, 5 inches long...........-. 6-6 o ee eee ees 8325. Pliers, Steel, with diagonal jaws for cutting, 5 AMCGHeSs LONG ss widen wern areata occa TATA ea ea aes 497 Ay aR. Te OH Ud: "RR H. T H O M A 5 Cc O M P A N YY 8327 8328 8329 8326. Pliers, Wire Cutting, Bernard’s. Open throat, parallel jaws, nickel plated, 54 inches long........ 2.60 8327. Pliers, Combination. A flat nose gas plier and wire cutter combined. Open throat, parallel jaws, nickel plated 5s cineches JOM pits cc nia 4 cu reenak rh ho Ain ak Sn elecaelGiacmiere we ateee le, aia Ouaweta less eann kecmeasdet waar 2.15 8328. Pliers, Nippers, End cutting, Bernard’s, open throat jaws, nickel plated, interchangeable parts. Its compound system of leverage makes this tool a very powerful cutter; 6 inches long...... 3.60 8329. Pliers, Combination; gas plier, wire cutter, wrench and screw driver combined. Drop forged from high grade tool steel and warranted free from defects. Nickel plated, 6 inches long 8330. Pliers; gas tongs or pipe wrench, 8 inches long. Will grasp pipe from 2 to 1,3; inches diameter.... 1.25 Prompt, accurate and economical service is much facilitated by the use of our original package quantities, or even multiples thereof, in the preparation of order lists. These packages also increase safety in shipment, convenience in unpacking and in checking invoices and safe storage on laboratory or store-room shelves. In many instances shown throughout the catalogue a discount is allowed for these original packages be- cause of the economies effected in our own handling. Metric quantity specifications when items are listed and packed on the dozen basis, and vice versa, result in unnecessary delay in shipment. 498 A R T H U_ R Hi. T H OF M AS C O M P A N_ Y POLARIMETERS AND SACCHARIMETERS To avoid confusion in the designation of instruments, we list as Polarimeters those instruments in which the compensation is accomplished by rotation of the analyzer and in which the angle of rotation is read in degrees of arc. All such instruments require a monochromatic source of light. Under Saccharimeters, we list the instruments designed for use in the sugar industry with an arbitrary scale which depends for its value upon the linear movement of a quartz wedge by which the rotation of a sugar solution is compensated. In these instruments, the polarizer and analyzer always remain fixed. Polarimeters are frequently furnished with a sugar scale in addition to the angular scale, but are seldom required with the sugar scale only. Saccharimeters can be used with approximately white light, though they are usually supplied with a stand- ard ray filter of potassium bichromate, or colored glass of equivalent spectral value.* The power of a substance to rotate the plane of polarization of plane polarized light has come, as a result of the work of Pasteur, Yan’t Hoff, Le Bel and others, to have wide significance in modern analytical methods, in addition to its application to the sugar industry as embodied in the modern Saccharimeter. The power of inert substances to exert influence on the rotatory power of optically active solutions has also assumed importance in analytical work, as, e. g., Acetone, and also Boric Acid can be determined in solutions of Tartaric Acid of known strength, and in other instances where the solvent used to dissolve an optically active substance has considerable influence on the rotatory power of the latter. As all saccharimetric scales are arbitrary, depending both upon the length of the scale division and the angle of the wedge, the resultant values have been occasion of both confusion and dispute. For example, the modern French scale is determined by the rotation of a control plate of right-handed quartz exactly 1 mm thick, having its optic axis perpendicular to the surface of the plate, and the normal sugar solution is defined as the amount of sucrose in 100 cc that gives in a 200-mm tube the same reading on the saccharimeter as the above mentioned quartz plate. Various values have been determined for such a normal weight of sucrose, but that established by the Inter- national Congress of Applied Chemistry, in Paris, in 1896, of 16.29 grams dissolved in 100-metric ce at 27° C, remains the official normal weight of the French government, and the basis on which most Saccharimeters of French manufacture are calibrated, unless otherwise ordered. The Ventzke Scale was based on 26.048 grams of sucrose in 100 cc of solution. This volume was later accepted as referring to 100 ce Mohr, which equal 100.234 metric ce. The confusion resulting from this difference, was considered by the International Sugar Commission, in Paris, in 1900, which Commission re-defined the normal weight in terms of the true, or metric cc at 20° C, as the standard for the 100° point of the Ventzke Scale. This re-definition of the normal weight of the International Sugar Commission is as follows: ‘‘The graduation of the saccharimeter shall be made at 20° C, 26 grams of sucrose dissolved in water and volume made up to 100 metric cubic centimeters. All weighings to be made in air with brass weights, the completion of the volume and the polarization are to be made at 20° C. This will determine the 100° point.” While the above definition of the fundamental standard is entirely clear it is in practice difficult to make up such solutions of the required purity for use in the manufacture of saccharimeters. Secondary standards or control plates are, therefore, made of quartz of such thickness as will rotate the plane of polarization through exactly the same angle as the normal sugar solution as above defined, and, therefore, read 100° on the saccharimeter scale. This angular rotation of such control plates for a known wave length provides the conversion factor on which the standardization of saccharimeters is based. Herzfeld and Schoenrock, Zeitschr. Ver. Zuckerind., Vol. 1, II, p. 826 (1900) and Vol. liv, II, p. 521 (1904), established the factor of 34.657° rotation as equal to 100° sugar, their work being based on the yellow radiation of sodium light (7 = 5892.5A). Most saccharimeters made since 1900, with the exception of those of French make, have been calibrated on the basis of this determination. In 1916, Bates and Jackson, at the Bureau of Standards (see Bulletin vol. ii, page 67, 1916), found that the most carefully prepared normal solution of both cane and beet origin read less than 100° on the saccharimetric scale. With a green mercury light (7 = 5461A) which is a more strict monochromatic light than that of the sodium flame, and after careful comparison between the rotatory properties of quartz for the mercury and sodium radiation, they finally established a conversion factor of 34.620° as the equivalent to 100° sugar in terms of sodium light, and this factor is now the official standard of the U. S. Bureau of Standards. As saccharimeters calibrated on the Herzfeld and Schoenrock data are in wide use and still being sold, the fact that a normal solution reading 100° sugar on a saccharimeter calibrated on the data of Bates and Jackson would only read 99.89° sugar on a similar instrument calibrated on the Herzfeld and Schoenrock data, should be noted in making precise comparisons. As no uniform practise has as yet been agreed upon by manufacturers of gaccharimeters and sugar chemists of various countries, it is our practice to state in our specific description of saccharimeters the data on which the saccharimetric scale has been based. : Within recent years there has been a strong movement to establish 20 grams as the normal weight of pure sucrose for an international saccharimetric scale. See Dr. C. A. Browne, The Polariscope Situation and the Need of an International Saccharimetric Scale, Journal of Industrial and Engineering Chemistry, Vol. 10, No. 11, page 916, November, 1918. At the time of preparation of this catalogue, no agreement had been reached, although we have supplied some saccharimeters of French make with scales based on the proposed 20-gram normal weight, for which the conversion factor was determined by the French manufacturers to be 26° 36’ and the thickness of the quartz plate for this angular rotation to be 1.227 mm. *The standard ray filter is made of a solution of potassium bichromate of such a concentration that the percentage content of the solu- tion multiplied by the length of the column of the solution in centimeters is equal to nine. POLARIMETERS, HALF SHADE, Duboscgq-Pellin, (Soleil 1819-1849, “Duboscq 1849-1886, Pellin 1886-1921). In these instruments the double field is divided vertically, and the polarizers are of the Jellet-Cornu- Duboscq type, which are adjustable for sensitivity, i. e., with variable half-shade angle which permits more or less polarization with reference to the greater or less absorption of the solution under investigation. They have adjustment for zero, and mirror for illumination of scales. The scales read in angular degrees, and_as compen- sation is by rotation of the analyzer, these instruments must be used with monochromatic light. The troughs were heretofore made to take only French tubes of 41.5 mm diameter, but are now made specially for us with troughs to take tubes of 29 to 30 mm diameter, such as are now in more general use. Listing and illustration on following page. 499 Fal Te Or (MA SS Cc O M P A N so Noy oo aga Ss POLARIMETERS, HALF-SHADE, Duboscq-Pellin (Continued) Polarimeter, Half Shade, Duboscq-Pellin, as described on preceding page, for tubes up to 200 mm long, and with scale reading by vernier to 2 minutes, 7. e., 1/30 degree of arc. On tripod base, in case with lock and key. Without tubes or lamp............. 000.0 eee ee . 163.50 8341. ditto, but with one each 100 and 200 mm tubes source of monochromatic light. On tripod base, in case with lock and key.... 8340. ere 187.00 tg len | Pry pred | ee Weert ad 8342. Polarimeter, Half Shade, Duboscq-Pellin Precision Model, as described on preceding page, for tubes up to 500 mm long, and with scale on divided circle 27 cm diameter reading by vernier to 1/100 of a degree of arc. This instrument was used by MM. Mascart and Bénart for the official determi- nation of the present French normal weight, 16.29 grams. d See Annales de Chimie et Physique, 1899. On tripod base, in case with lock and key. Without tubes or lamp 8343. Seta ree gh oeese . 310.00 ditto, but with one each 100, 200 and 400 mm tubes No. 8380, and No. 8410 Sodium Lamp for gas. On tripod base, in case with lock and key 3 Or ci en woos Ra Be 2 de fen Rin ate Rape orca eae dle si aye eer 40.00 A R T H U _ R H. TH 20M) AC SS Cc Oo UM oR ASIN TY. _,. PRECISION POLARIMETER, HALF SHADE, Hilger. In these instruments the polarizer is of the Lippich three-field type, providing the most satisfactory method of obtaining a variable half-shadow angle. The advantage of a variable half-shadow angle is that in each case the maximum sensitivity obtainable with the amount of light reaching the analyzer can be insured. If the solution to be examined is clear, and the light source very bright, a small half-shadow angle can be used (say 1° or 13° on the upright lever projecting above the polarizer). If, however, the solution absorbs a large proportion of the light, or if the latter is feeble, the half-shadow must be made greater (say 4° or 5°), the accuracy of the readings being thereby somewhat reduced. It is more accurate to work with a slightly greater half-shadow angle than with the angle too small, and consequent feeble illumination. This Lippich polarizer is of special construction in that the spar is cut with reference to its cleavage plane in such a way as to remove its tendency to split in course of time along the obtuse angle of the small prisms which form the separating lines of the field. There is no glass between the polarizer and anlayzer except two thin protecting windows, which have been carefully tested and mounted so as to be free from strain, so that with a zero half-shadow angle complete extinction can be obtained over all the field, even when a powerful light source is used. A low power telescope is used to observe the field of the polarizer, and to insure that the best definition is obtained, the aberration of the object glass of the telescope is corrected for observation at a short distance instead of for infinity, as is usual in telescopic objectives. The instrument is mounted on a substantial iron base, with rigid trestle supports for the polarizer and an- alyzer. The circle in which the analyzing prism is mounted is 7 inches in diameter; the scale is engraved on platinoid, which does not easily tarnish, and it can be read to .01° with the vernier. With the help of the two reading glasses, there is no difficulty in estimating to .005°. When an approximate setting has been made, the vertical milled head screw can be tightened; this brings the slow motion into action, and the accurate setting is made by turning the horizontal screw on the right hand side. This slow motion can be brought into play in any position of the circle, and is a great help for making accurate settings. The slow motion screw is of platinoid, which stands the corrosive atmosphere of a chemical laboratory better than steel. ; The observation tube is supported in a stout V trough, that can be raised or lowered, tilted, or moved laterally to either side. The design of the mount is such that the axis of the tube is, during adjustment, kept par- allel to the optical axis of the instrument. The trough can be quickly removed, when a clear space is wanted between the polarizer and analyzer for experiments such as the determination of the rotation of solids, etc. For most purposes, monochromatic light from an ordinary sodium burner will be found satisfactory, but for very accurate measurements, the Mercury Vapor Lamp is recommended, and for such work the polarizer should be used with No. 8351 Slit, and the analyzer with direct vision dispersing prism which deviates all the radiations of mercury except the one desired, making the instrument in effect a Spectro-Polarimeter. Prisms to give radiation with the yellow or violet ray of the mercury spectrum, Nos. 8352 and 8353, are quickly interchange- able, when this is desired. : : : ; ; These instruments are furnished in case of polished white wood, with handles and lock and key, and with drawer taking a number of tubes of different lengths. The tubes supplied with the Hilger instruments are guaranteed for length to within .025 mm at 20° C. 8350. Polarimeter, Hilger Precision, as above described, for tubes up to 400 mm in length, with one each tubes 100, 200 and 400 mm long, sodium burner and bottle of fused borax. In polished wood case with lock and key and drawer, but without spectroscopic attachments.......................... 902.00 eter, consisting of slit to fit the polarizer and a high dispersion 8351. Spectroscope Attachment for Hilger Polarim direct vision prism for the green ray. In mount to screw on the eyepiece.................. 61.7 8352. Additional Direct Vision Prism, only, for redray........... 0.0... cee ee 27.50 27.50 8353. ditto, but for the violet ray... 06... - 02ers ce ee eee ene een nee eas A R T H U _ R El T H O M A _ S§ Cc O M P A N Y 8356 8356—Front view SACCHARIMETER, HALF SHADE, Duboscq-Pellin. In these instruments the double field is divided vertically, and the polarizers are of the Jellet-Cornu-Duboscq type, which are adjustable for sensitivity, i. e., with variable half-shade angle which permits more or less polarization with reference to the greater or less absorption of the solution under investigation. They have adjustment for zero, and mirror for illumination of the scales. The troughs were heretofore made to take only French Tubes of 41.5 mm diameter, but are now made specially for us with troughs to take tubes of 29 to 30 mm diameter, and as are now in more general use. The rotation of the plane of polarization, which takes place in the solution under investigation, is compen- sated by a linear movement of a quartz wedge, which movement is read on the saccharimeter scale to 0.1 degree. A reading lens is provided for the reading of thescale. Heretofore, these saccharimeter scales have been calibrated on the basis of the official French weight of sucrose, 16.29 grams. We have imported a few instruments with scales based on the proposed normal weight of 20 grams, but by special arrangement with the manufacturers, these sac- charimeters are now made for us with the so-called “ International”’ saccharimetric scale, based on a normal weight of 26 grams, as mentioned on page 499. The adjustment of these instruments is based on the Herzfeld-Schoenrock conversion factor of 34.657 angular degrees = 100° sugar where a sugar degree is the 100th part of the rotation shown by a column 20 cm long of a solution of 26 grams of sucrose dissolved in water and the volume made up to 100 metric cc, for light from an incandescent gas mantle, passed through 1.5 cm of a 6% potassium bichromate solution, the temperature being 20° C for graduation, preparation and observation. These instruments are intended for use with any source of white light such as kerosene or incandescent electric, for which use they are provided with a standard bichromate filter. While the scale and compensation of these saccharimeters is not enclosed in metallic housing, they are with reasonable care entirely durable and satisfactory in sugar laboratory practice, and possess the advantage of easy accessibility for purposes of cleaning. In offering these French Saccharimeters, made in an establishment, the proprietors of which since 1819 (Soleil 1819-1849, Dubosceq 1849-1886, Pellin 1886-1921) have made repeated and important contributions to both the science and technique of saccharimetry, we feel it right to emphasize the work of other French scientists from the time of Biot, without which the sum total of our knowledge in this field would be comparatively small, despite the important contributions of both English and German physicists. See: The Polariscope Situation and the Need of an International Saccharimetric Scale, Dr.C. A. Browne, The Journal of Industrial and Engineering. Chemistry, Vol. 10, No. 11, p. 916, November, 1918. 8356. . Saccharimeter, Half Shade, Duboscq-Pellin, as above described, for tubes up to 200 mm long. On tripod base in case with lock and key. Without tubesorlamp...................02-0- 178.25 8357. sae but with two 200-mm tubes No. 8380, and Electric Lamp No. 8416. In case with lock and FENi7 ee aree ct iohes emcne rerent nr eae teeta eet weeded GRD TRL he Se ean a eect MANES Aero cy 217.85 8358. ditto, with two 200-mm tubes No. 8380, and Kerosene Lamp No. 8414 in place of the electric lamip.;~ injcase-with lock and:key wes. cis ins nies gcc lo waked nae y-ack ee ovine tutte hace Baie tides 202.60 A R YF H VU R H. T H O M AS Cc O M P A N Y SACCHARIMETER, HALF SHADE, Bausch & Lomb. In the development of this, the first American made saccharimeter, the manufacturers have been in close consultation with a large number of representa- tive sugar chemists in the U. S., Cuba and Hawaii, as well as with the Bureau of Standards. The instrument in both its optical and mechanical features is in accordance with specifications originally prepared by a committee of the above mentioned scientists. While of simple and rugged construction as required in a commercial instru- ment, several new optical and mechanical features tending toward ease and convenience in manipulation have been embodied in the construction. Optical Construction. Illumination is provided by means of a 100-watt, concentrated filament Mazda lamp, placed in a well-ventilated lamphouse with an opening in the side, over which is placed a plate of ground glass, which becomes the light source. Between the light source and the polarizer is placed the glass filter, which supplants the cell for holding the bi-chromate solution ordinarily used for the purpose of light purification. The filter has the same optical properties as 15 mm of 6% potassium bi-chromate solution and may be instantly removed from the optical system by means of a push rod, actuating a lever attached to the filter mount. The end of this rod, located at the observation end of the instrument, is easily accessible to the observer. This is of particular advantage when dark solutions are being measured. OP Q R > See WHE sy l A C6 6. FS H | oy aK L ~-| ota oe an fe oh 8366 Side View of Optical System A 8 © pe F.- a aT yx L ----f----fey es} (R= = = ==7F {ot = 4----- fetes Plan view of Optical System The polarizer is either of the Lippich or of the Jellet type.’ The Lippich Polarizer consists of two prisms, a larger of the Glan-Thompson type, and a smaller half-shade prism which is placed in front of it, covering only one-half the field. The advantages of this polarizer lie in the facts that the half-shade angle may be adjusted to any desired value, that it is very sensitive, and that the dividing line is practically invisible. The sharp edge of the half-shade prism, however, is fragile and subject to disintegration, causing the ordinarily invisible dividing line to appear as a ragged edge, which reduces the sensitivity of the instrument. : een ; The Jellett Polarizer is made of one prism. The half-shade angle (app. 7°) is fixed and the dividing line in even the best prisms is visible. In sensitivity it is not the equal of the Lippich. Its chief advantage lies in the fact that it is less liable to damage and is not easily put out of adjustment. ’ : Both types of polarizers have their advantages and disadvantages, and there is no decided preference among chemists in favor of one as against the other. For this reason either type may be chosen by the purchaser. The quartz compensation is of the single wedge type, which consists of a long movable wedge, a short, stationary wedge and a stationary plate, all mounted closely together in a dust-proof case with a removable cover to provide access to these parts in case of need. The length of the long quartz wedge has been chosen so as to provide sensitiveness of setting, together with uniform accuracy throughout the length of the scale, a factor con- trolled by the purity of available quartz. E ; The scale and vernier are engraved on closely adjacent plates of glass. In this way the troublesome black dividing line, which exists between the vernier and scale of all metal scales, is entirely eliminated. For the sake of additional ease in estimating fractional parts of tenths of sugar degrees, the ends of the scale and vernier lines overlap slightly. In this way estimations of 0.025 degrees sugar may be easily and accurately made. As regularly furnished, the saccharimeter scale is based on the conversion factor 34.657°, determined by Herzfeld and Schoenrock (Zeitschr. Ver. Zuckerind. vol. 1, II, p. 826, 1900, and vol. liv, II, p. 521, 1904), as the angular rotation of 26 grams of pure sucrose dissolved in 100 cc of water, solution and polarization to be made at 20° C, as re-defined by the International Sugar Commission, Paris, 1900. The scale covers a range of from — 3 to + 110 degrees. The vernier is double, providing for both positive and negative readings. . The scale field is illuminated by the same source which provides light for the polarized field. The light, reaching the scale field, passes through a filter similar to that used in the observation system, so that the scale field and the polarized field have the same color. Futhermore, the illumination of the scale field is so controlled that it is comparable in density to that of the polarized field at the end point. These features tend greatly toward comfort and the elimination of fatigue, which is of importance when a long series of observations is being made. 503 A R FF HU R H. T H O M A S$ Cc O M P A N _ Y 8366 SACCHARIMETER, HALF SHADE, Bausch & Lomb (Continued) . Illumination of the scale is obtained by means of two reflecting prisms in such a manner that the light is not cut off when a control tube or a constant temperature tube is being used. ’ The analyzer is a Glan-Thompson prism. __ The observation telescope and the scale reading microscope are focused with a spiral motion, which provides for a positive adjustment which is not easily disturbed by an accidental contact. Mechanical Construction. The instrument is mounted on a rigid trestle support with an I-shaped base, which provides for absolute rigidity. The trough or tube holder is V-shaped and is made of one piece of metal of sufficient thickness to prevent denting or bending under ordinary conditions of usage. It is 420 mm long, so that tubes up to 400 mm in length and control tubes may be accommodated. There is sufficient space between the ends of the trough and the splash glass holder so that solutions which may be spilled will drain off without coming in contact with other parts of the instrument. This clearance also protects against warping of the trough and the transmission of heat to the optics of the saccharimeter, when polarizations are made at high temperatures. The trough is removable, to provide for the accommodation of other forms of tube holders and baths which may be needed for special cases. The screws, with which the trough is fastened, are placed on the outside, so that they will not be subject to the corrosive action of solutions which may be spilled in the trough. The removable hinged cover, with which the trough is provided, is of sufficient length to cover the space between the trough and the splash glass holders so as to exclude all extraneous light. This cover folds back into a horizontal position, where it may be made a receptacle for tubes. The construction of the splash glass mounts permits of easy removal for the purpose of cleaning, a feature which will recommend itself to all who have had experience in the use of saccharimeters. Sugar tube cover glasses and splash glasses are of the same size. The analyzer and Jellet polarizer are so mounted that they may be removed and returned into position without disturbing the adjustment of the instrument. The movable quartz wedge is mounted, together with the scale plate, on a carefully fitted slide, which is driven by means of a rack and pinion without lost motion. The pinion is located at the upper end of a ver- tical driving rod attached to the trestle support. This rod is rotated by means of a large milled head, located a convenient distance above the table, so as to provide for a comfortable position for the arm. Either hand may be used in making settings. The vernier is adjustable by means of a differential screw, which provides a positive motion in either direction. The lamphouse is supported by means of a detachable bracket fastened to the trestle support of the saccharimeter in such a manner that conduction of heat to the polarizer does not take place. Permanent alignment of the light source with the optical system is secured by this construction, which is not disturbed when the instrument is moved. The lamp is adjustable vertically and horizontally so that the filament may be centered in the optical axis. Light shields are located at both ends of the instrument, so that practically no stray light reaches the eyes of the observer. To provide sufficient illumination for the purpose of recording readings, however, light is allowed to escape from the bottom of the lamphouse. Three observation tubes (100, 200 and 400 mm long), an adjusting key and a threaded tube for removal of polarizer and analyzer mounts are furnished with each instrument. 8366. Saccharimeter, Half Shade, Bausch & Lomb, as above described, with Jellet polarizer, for tubes up to 400 mm; with attachable electric light, and one each 100, 200 and 400 mm tubes No. 8388. In CASE: WIE DY OCIS aN CKO rc tine Shee eae ne a nd ee en, led oat et wane ae ae Ba a Meh cy tha ae Ra 525.00 8367. Saccharimeter, Half Shade, Bausch & Lomb, as above described, with Lippich polarizer, for tubes up to 400 mm; with attachable electric light, and one each 100, 200 and 400 mm tubes No. 8388. In GASERWA UM LOCKMAN EK OW er starvrsrsites seine arcu aerate ce psn al esses et tute oe cle Reagan AM nh treet 525.00 il ih Wun — i UH i 8370 SACCHARIMETER, Laurent-Jobin. A French instrument of new design in which are incorporated the most recent suggestions of the committee of American sugar chemists. The polarizer and compensator are en- tirely enclosed but are readily removable and each instrument is supplied with a separate containing case for polarizer and compensator, so that they can be removed from the Saccharimeter during periods of disuse and more adequately protected from climatic and other deteriorating influences. The polarizer is of the Laurent type with half wave-plate, reeommended by this maker for industrial use as preferable to the Lippich polarizer. In the Laurent polarizer the separation line is sharp and clear and unlikely to change. The half-shade angle of the polarizer is variable, permitting suitable adjustment between illumination and sensitivity, a feature valuable in the polarization of dark colored syrups. The movement of the compensator is by a milled head in convenient position for the hand and connected with the instrument by a toggle joint, and the scale is illuminated by means of a prism from the polariscope lamp. A practical point of importance in the operation of this instrument is the simultaneous adjusting of the zero with the shade in the field. As regularly supplied by us, the trough of this Saccharimeter is fitted to take tubes of 29 to 30 mm flange diameter, so that all tubes now in common use in the U. S. can be used with it. The Saccharimeter scale is adjusted for a normal weight of 26 grams based on the Bates-Jackson angular conversion factor of 34.620°. This instrument is manufactured in the establishment founded by Soleil Pére in 1819, where have been designed and made many important polariscopic instruments as used by distinguished scientists of France, and other countries, in their application of the principle of polarization to chemistry and physics. Samples of this instrument have been submitted by us to prominent American sugar chemists with uniformly favorable reports as to accuracy of readings and satisfactory design. 8370. Saccharimeter, Laurent-Jobin, as above described, for tubes up to 500 mm long. Without tubes or VATA 3. feoeicesy 3 oss cet aren cere tis nee ty Ua peak SS nel alee, ee meee dal tas Ua Re te at ahd ree ote Aa ON eR aN 400.00 8371. ditto, but with one each 100, 200 and 400 mm tunes, and No. 8416 Electric Saccharimeter Lamp. FORCUSE COME ORVOlUSS on hha ce mente o eben shrl eshte aie d weed Wines ae ahd eed ennteetacs poner as uae wea 444.10 8372. ditto, but with No. 8414 Kerosene Lamp in place of the electric lamp...................... 428.85 ACCESSORIES FOR POLARIMETERS AND SACCHARIMETERS 8380 POLARISCOPE TUBES, A. H.T. Co. Special. These tubes are of glass with metallic screw cap ends 29.3 mm diameter. They are made with and without enlarged end for bubble. The regular end takes cover glass 15.5 mm diameter and the enlarged end for bubble takes cover glass 23.7 mm diameter. The cover glasses are made of selected optically inactive glass, and the tube lengths are guaranteed to within + 0.08 mm, a tolerance satisfactory for most routine work. : The Bureau of Standards tolerance for length is + 0.04 mm, and the tubes with Bureau of Standards certification are, therefore, within this limit of error. The Bureau does not report the exact length of the tubes when the error falls within the above-mentioned tolerance of + 0.04 mm. 8380. Polariscope Tubes, A. H.T. Co. Special, as above described, without enlargement fe Panble, Teenie this mindy. catee ops, woh Suh eee Ge Oe Ba a atop ee Miers pecs 100-200 -~=— 400 Dea MeN eet niugil alee a 4.00 5.00 5.50 BCH per eee tlt sco near eee en fies Oucee Ronee a 8381. ditto, but with Bureau of Standards certification........................ 5.50 6.50 7.00 8382. Polariscope Tubes, A. H. T. Co. Special, as above described, with enlargement for bubble. Deneth fmm ssc rece eaten e ecient aarti teed ee ae Ta a stay sea ase 100 —-200— 400 Daeeleseg oan ee essen eee PUT ian aaa een 5.00 6.00 —~6.50 8383. ditto, but with Bureau of Standards Certifications MALS G OND

Av UN VY | / : 8650 8655 DIPPING REFRACTOMETER. This refractometer also depends on the observation of the border line of total reflection in a telescope for method of measurement, but the range of the instrument as compared with refractometers of the Abbe type is very much less, being nD 1.325 to nD 1.367. Measurements, however, can be made to 0.2 of a scale division, and under favorable conditions to 0.1, and as the latter value corresponds to 34 to 4 units of the fifth decimal place of nD, the Dipping Refractometer excels in accuracy all other refractometers, except those of the Interference type. The Dipping Refractometer is used to determine the refractive indices of fluids, such as alcoholic and weak acid solutions. In ordinary practical work, the divisions of the scale as read off the ocular give the desired result of the measurement, although in some cases the reading may have to be converted by means of the tables furnished with the instrument, into the exact values of the refractive indices. This method of measurement applies particularly to the analysis of standard solutions and the exact and rapid determination of the concentration of solutions. In solutions such as ether, which evaporate quickly, the metal beaker which fits over the prism end of the refractometer is used. The instrument is then held with the prism pointing up. The beaker, with the metal cap removed, is securely fastened in place on the refractometer, and the liquid for investigation is poured into the beaker until the latter is quite full. The cap is then replaced and locked in position. The solution for examination is now air and watertight, and the refractometer is hung from the wire frame of the bath—with the rack for holding glass beakers removed—with the metal beaker immersed in the tank bath. For the investigation of solutions such as blood serum, obtainable only in small quantities, or solutions such as molasses, too deeply colored to be measured by other means, an auxiliary prism is supplied, which in connection with the metal beaker requires only a few drops of solution for investigation. In using the auxiliary prism, care should always be taken to apply enough of the solution to fill completely the space between the two prism surfaces. 8650. Refractometer, Dipping, Bausch & Lomb, with metal beaker for volatile solutions, table for transposing scale divisions into refractive indices, table of scale readings for distilled water at temperatures from 10° C to 30° C, and directions for use. In polished wooden case.................. 200.00 8651. Auxiliary Prism, for B. & L. Dipping Refractometer, for use where only very small samples are avail- AND 1 Ges Soe Pos saepthes ce Pacey cece taste ester ale oeccoslcearertnd Sav se Gas fake OER ADE Sacto SRO AN AT tC PAYA Aon Ate agin 9.00 8652. Heating Trough, with glass plate in bottom, levelling mirror, support for refractometer and shelf for talking 24-small glass: beakers: > D C | | | | faa (eee ee ssaa| D AE Eesi-F op = Fig. 1 = | oi | ae For convenience we will suppose the whole optical system to be divided by a horizontal plane through the optical axis into an upper and a lower half, and we will at first confine our attention to the lower half, of which Fig. 1 is a view from above. Fig. 2 is a side elevation of the whole system. Light from a narrow vertical slit A is collimated by an achromatic object glass B in front of which are two vertical slit apertures C, 4 mm wide, 27 mm long, and 12 mm apart. The two parallel beams which pass through these apertures after traversing the two tubes D and E containing the gases to be compared fall each upon a thin glass plate inclined at about 45° to the optical axis, one of which, K, is fixed, while the other, L, can be rotated about a horizontal axis, perpendicular to the incident light, thus varying the thickness of glass through which the light must pass. The two beams are then brought to a focus by means of the achromatic telescope object glass, Q, and the image observed with a small cylindrical lens, R, which gives a very high magnification in a horizontal direction without the loss of light which would accompany the use of a spherical lens. The telescope is provided with a helical focusing adjustment, actuated by the knurled ring, V. The two gas tubes are each 100 cm long, and 1 cm square section. They are of brass, and the ends are closed by plane parallel glass windows. The tubes are supported on two standards and may be adjusted laterally by a screw and an opposing spring plunger. A milled nut provides vertical adjustment at each standard. The upper halves of the two beams after leaving the two slits travel uninterrupted until they reach the prism H, which is simply a thick glass plate inclined to the axis and beveled. The sole object of this prism is to bring the upper beam adjacent to the lower beam with a sharp dividing line, thus cutting out the obstructions, such as cell walls, etc., which would otherwise form a gap between the beams, and eventually between the band systems. a 7 | H Kel Fig. 3 Fig. 3 shows how this is accomplished. The beveled edge of the prism itself forms the dividing line between the two beams. The purpose of the upper beam is to provide a system of bands which remains immovable under all conditions, thus constituting a zero position to which the movable band system may be referred. The cylindrical ocular is a complete cylinder of glass of very small diameter with its axis vertical. Its function is to provide a very high horizontal magnification (about 50 diameters) of the vertical band system formed at the focus of the telescope; the bands are necessarily very close together on account of the unavoidable distance apart of the two slit apertures. At the same time, because the lens has no power in a vertical plane, horizontal lines will appear sharp at the ordinary distance of vision. Consequently the edge of the prism H is seen clearly dividing the upper band system from the lower. 524 AS OR i ee Us eR H. T H OF M A 8 G © M “cP A IN ¥ RAYLEIGH INTERFERENCE REFRACTOMETER FOR GASES (Continued) A glance at the diagram will show that the upper band system will remain immovable under all conditions, as there is no movable element in the optical path. The lower system, however, will only remain stationary so long as the movable compensating plate L is kept fixed, and the two tubes are filled with substances of identically the same refractive index. Briefly, then, the method of using the instrument is as follows: The instrument is sent out so adjusted that the upper band system is always visible. The tubes are then filled with identically the same substance, the slit being illuminated with white light, and the compensating plate is turned until the system of bands in the lower field becomes exactly continuous with those in the upper field. This is accomplished by means of the divided drum on the micrometer screw which presses against a hardened steel block at the end of the 8-inch lever. Its action is _opposed by a spring plunger. When exact coincidence is obtained, the reading of the drum is taken. This is then the zero of the instrument. If now a substance is introduced into one of the tubes of a slightly different refractive index from that in the other, the bands will be displaced, and a further adjustment of the compensating plate will be necessary once more to effect coincidence. The second reading of the drum then indicates the relative refractivity of the two substances. It should be observed that the nature and purpose of the instrument render it impossible to calibrate the drum to read direct in refractive indices. The drum is, therefore, divided into 200 equal divisions, and the pitch of the micrometer screw being } mm, a rotation corresponding to one division of the drum moves the end of the lever through .0025 mm, and, therefore, turns the compensating plate through an angle of 23 seconds. ; In its zero position the compensating plate is at about 45° to the incident light. In this position a change of tilt of 5 minutes is required to produce a shift of one band when using the green mercury line. Settings can be made to less than one-fortieth of a band, 7. e., to 74 seconds, or three divisions. ; The relative refractivity of two gases can be measured with considerable accuracy by means of this instrument. Rayleigh, in measuring the refractivity of argon, using his early experimental model, which had only 12-inch tubes, and in which the sensitivity was limited by the accuracy of reading a mercury manometer with only 8-inch total pressure, succeeded in obtaining an accuracy of one part in a thousand. See Proc. Roy. Soc. LIX, p. 201, January, 1896. With the present instrument, wherein the accuracy of reading exceeds that of setting, the error is probably less than one part in twenty thousand, corresponding to an error in refractive index of .000,000,015. The in- strument is consequently well adapted to determining the quantity of a known impurity in a gas of otherwise fixed composition. It has been used with great success in experiments on the permeability of balloon fabrics to hydrogen, the sensitivity for this work being such that it is possible to detect a quantity of less than .01°) of hydrogen in air. See Technologic Paper of the Bureau of Standards, No. 113, July 2, 1918. The instrument is, of course, equally valuable for any other kind of diffusion work. Another very valuable application is the estima- tion of any one constituent of a gaseous mixture. Thus the CO, in flue gas may be estimated by comparing the refractivity of the untreated gas with that of the same gas after absorption of the CO, with soda lime. In the same way it may be used for the control of gaseous products with reference to any desired constituents, e. g., the CO or SO; content of coal gas. Appended will be found a list of gases and the percentage which would be detectable (as an impurity in air) assuming an accuracy of setting of 1/40 band. Even greater accuracy than this can be attained with a little experience. In each case, it is, of course, necessary to calibrate the instrument for the particular work for which it is required. Thus, if we are estimating hydrogen as an impurity in air, a shift of 1/40 band corresponds to about 01%. If, however, we are estimating the quantity of helium in argon, the same shift corresponds to only .006%. It may be found preferable for some work to read directly in difference of refractivity of the two tubes independently of what gases they may contain. This may be done by making a small correction to each reading 7, of the form 1’ =r — ar? where a is a constant; r’ is then directly proportional to the difference of refractivity of the gases in the two tubes. See Adams, Journal of American Chemical Society, 1915, p. 1181. Quantities of Gases in Air Detectable by Rayleigh Interference Refractometer: Minimum observable shift assumed to be 1/40 band. Hydrogen 01% Argon.... 15% Water....... . .04% Carbon Monoxide .03% Nitrogen : 3% Helium........ 006% Hydrogen Sulphide .0045% Carbon Dioxide .0095% Nitric Oxide. . .0065% Sulphur Dioxide 034% Chlorine....... 003% Ammonia....... 017% Bibliography of Rayleigh Interference Refractometer, Original Arrangement and Laboratory Type 2 { Proc. Roy. Soc. (A) vol. 59, p. 201 (1896). Lord Rayleigh \ 4 oe Me ae” BY 97 (1898). g Proc. Roy. Soc. (A) vol. 62, p. 225 (1897). Ramsay & Travers r i of ss a «64, p. 190 (1899). Le Gy, 831 (1900). “Study of Gases,”’ Macmillan, 1901. Zeit. f. Phys. Chemie, Vol. 36, p. 232 (1902). Thesis. Amsterdam, 1904. Zeit. f. Elektrochemie, Vol. 16, p. 37 (1910) Zeit. f. angew. Chemie, Vol. 23, p. 1393 (1910). Zeit. f. angew, Chemie, Vol. 19, p. 1717 (1906). Travers. E. A.J. Cunaeus C. G. Gerrits L. Stuckert .. é F. Haber & F. Lowe F. Haber : \ “ “© Blektrochemie, Vol. 13, p. 460 (1910). Technologic Paper of the Bureau of Standards. J. D. Edwards {No 113. Jour. Amer. Chem. Soc. 39, p. 2382, 1917. Adams Jour. Amer. Chem. Soc. 39, p. 1181, 1915. Supplementary and Classified Bibliography of Rayleigh Refractometer: Inst., 177, p. 673 (1914).\ Connection between Density and Refractive f Index of Gases. Calibration. Matthews. J. Frank. Gale, Phys. Rev. 14, p. 1 (1902). J Edwards, (Bull. Bu. Stds: 14 p. 474, 1917) Jour. Am. Chem. Soc., 39 p. 2382 Ls . . (1917) Calibration. Adams, J., Wash. Acad. Soc., 5 p. 267 (1915). Jones & Partington. Phil. Mag., 29, p. 28 (1915). \ Ramsay & Travers. Proc. Roy. Soc. Lon., 62, p. 225 (1897-8).J Adams, Jour. Amer. Chem. Soc., 37, p. 1181 (1915). Burrell & Seibert. Bull. Bu. of Mines, No. 42, p. 73 (1913). Edwards, Tech. Papers, Bu. of Stds. No. 131 d Meggers & Peters. Bull. Bu. Stds., 14, p. 697 (1918). Edwards & Ledig. Aviation, 6, p. 325 (1919). Mohr, Zs. Angew. Chemie, 25, p. 1313 (1912). Kreisinger, Augustine & Ovitz. Bull. Bu. of Mines, 135, p. 107 (1917). 525 . Calibration and Deviation of Refractive In- dices of Mixture from Simple Law. Errors Due to Dispersion. Effect of Lowered Oxygen Content on Meas- urements of CO» Content. Applications of Gas Analysis. Measurements of Refractive Index of Air. “Significance of Oxygen in Balloon Gas.” Analysis of Flue Gas with Interferometer and by Chemical Analysis. Analysis of Flue Gas. nn Ty iti An WN SN vn sa 8680 8680. Refractometer, Interference, Rayleigh-Hilger, for gases, as described on preceding pages, with double gas tube 100 cm long, but without illuminating lamp...........0....0....00 2.000 .0000. 620.25 868i. sGas Taubes; only, 100 cmulOn eer. pk des kangen nel aa es ag Ades Bean ey Retest lh Wud GkOeedl sane 40.50 Adaptation of the Gas Interference Refractometer for Investigation of Liquids. By the addition of the accessories listed below, the Gas Refractometer can be readily adapted for the investigation of liquids. Where the investigations are to be conducted on liquids only, we recommend the purchase of the Liquid Refractometer listed below because of its much shorter support stand and more convenient manipulation. Where there is a possibility of both gas and liquid investigations, it is necessary that the Gas Refractometer be purchased with the accessories for liquid investigations, because of the impossibility of adapting the Liquid Refractometer to the investigation of gases, inasmuch as the long gas tube cannot be used on the short support provided with the instrument for liquids. 8682. Accessories to Gas Refractometer for Investigation of Liquids, including support for the liquid cell, holder for thermometers, liquid cell 1 em thick with interior surfaces accurately parallel to 1/50,000 inch, two tested thermometers, and compensating plates suitable for liquids, readily interchangeable with those for gases 135.00 “3624. ts RAYLEIGH INTERFERENCE REFRACTOMETER FOR LIQUIDS, Hilger. This instrument differs from the Rayleigh Interference Refractometer for gases in the following particulars: (1) the instrument is much shorter, since the length for the gas tubes is not required, (2) instead of gas tubes an accurate cell 1 cm long is supplied, the body of which is made of a solid piece of glass on which end plates are adhesed by the Hilger British Patent Process 103233/ 1916; (3) the movable plate is in the upper beam instead of the lower, so that the comparison beams of light which produce the immovable reference bands are produced by rays which have passed through the body of the cell. The cell is corrected by the Hilger British Patent Interferometer, 103832/1916, so as to introduce no error; (4) the plates of glass in the movable beam, the thickness of which determines the range of the apparatus, is 4.7 mm thick instead of 1 mm, so that the entire instrument has a range of .008 instead of .000017. The advantage of the modification (3) is that the part of the liquid under observation is remote from the surface; thus the differences of temperature and of concentration which are liable to occur in the neighborhood of the surface are avoided. 8684. Refractometer, Interference, Rayleigh-Hilger, for liquids, as above described, with double, one-piece, liquid cell 1 em thick with the interior surfaces ee ee to aus 000 inch. Without illuminating lamp. . tie octmne tite ........ 620.00 8685. Liquid Cell, only, 1 cm Thich oak ties Miser ks ete ame ER SEC deh O Ne ey Ob thd ininn NEE RARer G 104.50 Note—Extra Liquid Cells of any other desired thicknesses from 0.25 cm to 2 cm, on special order only. Price on application. 8686. Iluminating Lamp, consisting of Pointolite lamp, with resistance and lamp case with raising and lowering MOLIOMs, CHOL WTOSViOl Gs SO sas esse seed pete oyster tN) ey ea seem ae ree AA a Tee an foctt, sints Name ecus oe meson oat 139.25 8687. Bulbs; only; for Pointolite Lamp. 320 ton vei o aoa se teak Cage smd aaa oR arewaere hee we 8.50 8688. Illuminating Lamp, consisting of stand with ordinary metal filament lamp. This is a less expensive lamp than the Pointolite listed above. For 110-volt circuit 526 8691. 8692. 8694. 8691. 8695. 86956. 8700. 8702. 8704. 8706. "8707 8708. 8709. 1342. 3702 8709 Respirator, Cover’s Automatic, of soft white rubber. Easily kept clean and in conformity with the face. Filtering device consists of sponge and silk disc. Many thousands of this form of Respirator are in use for the protection of throat and lungs in laboratories, factories, mines, etc......... 1.50 10% discount in lots of 12. Sponges, for use in Respirator. Per dozen.............0...00 ccc cece vce c vee e vee cv ee ceees 1.80 Silk Discs, for use in Cover’s Respirator. Perdozen....................00.0 0 cc eevee vee eveee 1.00 Respirator, Hayward Automatic, of aluminum with rubber pneumatic cushion to insure conformity with the face. Filtering device consists of sponge and wire gauze. A satisfactory and widely used form OL POS PITA LOL eee renee et erty SRA eat aR tear aun ct tenes Leaetrae RUE em na chcteet tet bate aa neice Recon 3.35 10% discount in lots of 12. Sponges, for use in Respirator. Per dozen..........0.0000 000 occ 1.80 Wire Gauze, for use in Hayward Respirator. Each..................0.00000 0000 c eee eeee . 380 Rubber Pneumatic Cushion, only, for use in Hayward Respirator....................... 000 e eee 1.00 Retorts, of heavy polished copper, suitable for making oxygen, etc. Diameter of tube 12 mm. Capacitysemlicaiie tc Citic dene is tn So me hua es eaters tns ea, 250 500 1000 2000 ACN ecg Cerne tne Heenan en ene atr pale Aen ort Real 2.80 3.20 3.75 5.10 Retorts, heavy copper, tin lined, as used in distilling apparatus No. 4700. Capacity. gallons: no.i5 ccs 5 oe a chk as See RAMed eee ima’ 3 1 2 3 5 BACH es bees oyhen heer CUNT ERC EUR Ce In age de metrat: 8.00 11.20 15.20 20.00 22.40 Retorts, Iron, for distilling mercury, etc., with removable cover fastened by screw clamp and with delivery tube ground into cover. Capacity ...................005 2 pt. 1 pt. lqt. 4 gal. Bache eee creer een nae re ener pecs 3.50 3.85 4.25 5.15 Retorts, Pyrex Glass, with tubulation, but without glass stopper. Capacity, ml. 125 250 500 TORCH ie es ihe Laks ta Me Aes te Vata Cee eae tates aaa ae che a Oe nen MY 1.60 2.00 3.00 Retorts, of glass, without tubulation or stopper. Size,ml............ _ 150 250 500 1000 a Coss Fon dip os rs oe Ss ee tea eee ae iS SE eer 25 30 45 .65 ditto, but with tubulation, but without glass stopper. Capacity aml ice ain eer ca iene dou. 8 Pieces ee ecto sk 150 250 500 1000 2000 ACH ee cals Artem scents rien ech ete ae eee ate mts 50 .65 85 1.10 1.35 ditto, but with tubulation and ground-in glass stopper. Capacitysiml) noises say valu cenapin en creamer take 150 250 500 1000 2000 | DE Ree ner ar em eter RRC ER SR or ore aN Emre CeIn ER rene er -70 95 1.10 1.35 1.65 Retort, Pyrex Glass, capacity 250 to 290 ml; according to the specifications of, and as used in Barrett Manufacturing Co. Test H-6, and A.S. T. M. specification D-36-18 ..................... 1.90 10% discount in case containing 36. . 527 A RK T HH VU R H. Fr H © M A S C O M P A N _ Y RHEOSTATS 8712 SLIDING CONTACT TUBE RHEOSTATS, T. R. Laboratory Type, specially selected for use in chemical and biological laboratories. These rheostats are constructed for regulating small currents in the smallest pos- sible steps without opening of the circuit. The resistance element of this type rheostat is wound on a metal tube having a thin enameled wall. This unit is mounted on two iron stands or brackets, one at each end, which provide for fastening the rheostat to table or other permanent base. The slider box is mounted upon the triangular rod, which is parallel to the tube, and the brushes are mounted upon the box. The brushes consist of several laminations, with one of the heavier material on the outside to give a proper ‘‘set”’ to the contacts, and thus make constant and even contact when adjusting or moving the slider. Good ventilation of the rheostats is the result of using a tube, and therefore, the maximum temperature for any given load is soon reached. Also the coefficient of expan- sion of the tube is practically that of the resistance element. The resistance element, bare wire or strip, is made from a special resistance alloy, and is covered with a thin film of oxide, which gives sufficient insulation to overcome the small potential difference between adjacent turns. Therefore, it is obvious that no empty space between turns is necessary, and the entire surface of the tube can be used, thereby giving the greatest capacity possible for given physical dimensions. Rheostats of this type and design have a very wide range of utility as series and parallel resistance. They may also be used as potentiometer resistances and for calibrating all kinds of measuring instruments, and watt-hour meters, for photometric researches, for electrolytic investigations, etc. Where it is a question of regulating small currents within very wide limits, as when testing voltmeters or adjusting the candle- power pl mean destent lamps at various voltages, the use of the rheostat by the potentiometer method is suggested. The resistance having both ends connected direct to the source of current, the load-resistance is connected at one end to the slider by means of the binding posts on the slider rod, and at the other end to one pole of the source of current, so that the rheostat winding forms a pressure cascade from which any pressure from zero to the supply pressure can be obtained by the adjustment of the sliding contact. Each rheostat is provided with three double binding posts, one on the slider rod and one at each end of the resistance wire. It is possible, therefore, to connect in series with outside resistance. These rheostats in continuous duty work, with their rated current capacities, will have a temperature rise of approximately 200° C and are 16 inches long by 1.6 inches diameter. Approximate Resistance Continuous Capacity 8712. Rheostats, Sliding Contact Tube, T.R.Laboratory Type 3200 ohms 0.3 ampere 8.00 8713. ne Gi ey pe oS ae oe 1750)“ 0.4 re 8.00 8714. “ “ “ ‘cc “ 6 ““ 920 ‘“ 0.6 oe 8.00 8715. os ee a ce pe ie a 630“ 1.0 ns 8.00 8716. ne 7 re oS a se ef 3870“ 1.2 a 8.00 8717. oe “oe oe “ce oe oe ee 210 ce 1.5 “ce 8.00 8718. oe oe oe ee oe oe ee 120 “ce 2.0 “cr 8.00 8719. oe “ee “ce oe “es oe oe 70 “ce 2.8 cc“ 8.00 8720. “ce “cc “é oe oe oe “ce 50 oc 3.3 “cc 8.00 8721. “ee “ce “ce “ee oe “ce oe 25 oe 5.0 “ce 8.00 8722. “ se ae & ie oe 14 “ 6.5 = 8.00 8723. oe “es oe oe oe “ee “ese 8 ce 8.5 “ce 8.00 8724. “ee “ee “se “se “ee oe “ee 4 “cc 12.0 “ce 8.00 8725. “ «“ “ “ ““ ““ ““ 23 6 14.0 “ 8.00 8726. i a = ce ry = is Dien 16.0 oe 8.00 8727. “ “ ‘“ “ “ “ ““ 1 “ 20.0 or 8.00 8728. “ec oe oe ee oe oe oe 0.6 “ee 25.0 “cc 8.00 NoTtE—Rheostats similar to above, 8 inches long, also double and triple tube design, and in other capacities, also Stone Rheostats and Compression Carbon Rheostats supplied on special order. 8740. Coil, 10,000 ohms, 1/5%; as used in connection with Enclosed Lamp and Scale and Portable d’Arsonval Galvanometers in potential measuring outfits listed on page 252, etc., to protect the galvanometer TROMIOVETIOAG: 8A. s erect aa ssie eae Giabeene tan ene Blades head sine OHA Reh Ga 4G a nee Ma pad ata tes ten NN 4.00 8741. ditto, mounted in Bakelite tube on base with binding posts......... RHEOSTATS AND TRANSFORMERS FOR USE WITH PROJECTION APPARATUS 8540. Rheostat, for use with 400-watt, 110-volt Mazda lamp, when used on 220-volt circuit.......... 9.50 8541. Rheostat, for use with 600-watt, 110-volt Mazda lamp, when usedJon 220-volt circuit.......... 12.00 8542. Rheostat, for use with 1000-watt, 110-volt Mazda lamp when used on 220-volt circuit......... 14.00 8543. Rheostat, for 30-volt, 30 ampere (900 watt) Mazda lamp, when used on 110-volt d.c. With starting VEVER sts. tancua des Peete RSE SLES Aesth danas doce t fOlscee ACM Seat ae ea ites lene WR Nee Sho are hp Se 40.00 8544. Transformer for 30-volt, 30 ampere (900-watt) Mazda lamp, when used on 110-volt, 60 cyclea.c. With ammeter and adjusting shaft for controlling amperage in starting lamp.................. 55.00 528 3748 6990 RHEOSTATS AND TRANSFORMERS FOR USE WITH METALLOGRAPHIC OUTFITS, MICRO LAMPS AND MICRO-PHOTOGRAPHIC APPARATUS 6555. Rheostat, for use with 6-volt, 24-watt, gas-filled Mazda lamp, on 110-volt d. ec. circuit. .. ...... 8.75 6556. ditto, but tor 220=volty. dee: cincuiticee aioe poe he ese peek A ee ee : .. 12.50 6553. Transformer, for use with 6-volt, 24-watt, gas-filled Mazda lamp, on 110-volt a. ¢. circuit. . .. 7.50 6554. ditto, but for-220-volt as CG: CIRCMIbs. oe Uy ee wea ences aa ene Halden Ge bone Min elas Gents 3% 11326 6557. Rheostat, fixed form, 4.5 amperes, for use with hand feed arc lamp on 110-volt circuit . . ... 8.75 6558. ditto; but-for:220-Vvoltcmcuitea ss Bae ack rots os Cee ee ee Sen aha Gee . 12.50 6990. Rheostat, for use with 15-watt, 110-volt Mazda lamp, on 220 volt circuit...... Nicene . 4.25 3748. Rheostat, for use with 100-watt, 110-volt Mazda lamp, on 220-volt circuit... .. . 8.00 8750 8750. Rings, Concentric, Copper, tinned inside, with cover, for Water Baths, etc. Number of rings in set............ 2 38 4 5 6 if 8 Outside diameter of set, inches. .... 3 33 43 54 62 83 98 Per S@tia op cGin dynes ha Gre iad bls oe -40 56 72 -96 1.60 2.40 4.00 8751. Rings, Concentric, Porcelain, with cover, for use in water baths, steam baths, etc. Number AN Sets eas 3 eck cies giana cae ee ee ee ees 3 4 5 q 9 Outside diameter of set, mm................. bars 74 94 115 156 197 POP SObinic srcske seo ee TS BS eas Bh -60 -95 1.75 2.10 3.15 8752. Rings, Concentric, of japanned cast iron, with screw clamp on largest ring for attaching to upright support; outside diameter of largest ring 8 inches, with four rings in set. Perset.................. 1.60 8758. Rings, Suberite, for supporting flasks, dishes, etc. These are superior to the straw rings commonly used for this purpose, being neater and more durable. Outside diameter, inches.............-..--- 3 41 5A 63 8} 92 Inside diameter at bottom, inches...... ie 13 23 33 4t 6 7h 25 -45 -60 -90 1.20 1.45 & ht fy A oR a a oe hoe eh S!)~CO COMO Oe a upg 8760. Rings, Support, of japanned cast iron, with screw clamp with brass screw. Distance from center of support to center of rings 2$ inches. Suitable for use on upright supports with tripod base and supports with rectangular base in the smaller sizes. When used on the same support rings will be concentric. Inside:diamietersinehes:s 4 erg py fe a ee ett ary gk suid AO eRe ed aadey dad idag ean 24 3h AC Misch Sack cecal otc eee ac onsd name na hcp aa curt tone tae RRRn ers ue heawa a Cea creer ena 12 18 10% discount in cases containing 25. 8761. ditto, but with distance from center of support to center of rings 44 inches. Suitable for use on supports with rectangular base in the three larger sizes. When used on the same support, rings are concentric. Insidesdiameter;“inchesicc4 set et oe ea eee lay 22 3t 4} 52 ACIS hee hte ran cernee tne cto ere e enh dante See Dae Oe gst NEA Nek ASR Matern Wey -16 18 -20 30 10% discount in cases containing 25. 8762. Rings, Support, of japanned cast iron, with screw clamp and with opening for use with leveling bulbs, etc., so that same can be removed and replaced without detachment of rubber tubing. Inside-sdiameter, in Chessy secre o cccus oe. aati tas sev es Bak arb a as gee ee a tc 24 3t AC He irasted sta sacueag. os seo ind (au sdae enema agate tar sna) ate lays ate euaeaosTek Wrettieee eae roar a Am Sioa anea be -20 25 8764. Rings, Support, of japanned iron, with straight extension bar 8 inches long. Distance from end of shank to center of rings 93 inches. A clamp holder such as No. 3214 is necessary when these rings are to be attached to an upright support. Inside. diameter, inches... o..%. 6s Goan Ane See te a en 2k 3+ 4} 53 AC cee eet te neg reg Pony et con ee aye kee eee re 14 15 -18 .30 10% discount in cases containing 25. 8770. Roasting Dishes, Denver Fire Clay, very shallow. Diameter sin CHesvoe. hs sud gnu ances Bh al. cea pd We Ee aie tone Alene Be 3 4 5 6 POR MOZEM sb scsk seek tse ead ions ht acts Bene pg Ms ee Bharat Mareen 1.80 2.25 2.60 3.90 _ un CW | | . al em Mi mM \ | \ i = ry i n hi Wiis oa " Mil f } 3 “aug tt ei i mT] i} nets qm) ul 8772 8773 8774 8776 8777 8772. Rubber Bulb, of pure, acid-cured red rubber, as required in opsonic and serological work; about 2-ml capacity, as used in Dr. Wright’s laboratories..........00.. 000.000 ccc cece cece cece 14 10% discount in carton containing 12. 8773. Rubber Bulbs, of pure black gum, for dropping pipettes, medicine droppers, etc., superior quality. Capa cttysomnlar. cs cnr aed tia foie iy niet aeons Breage igo hn) aren lon quenced ah yin Mace t 1 2 RCTS OZON arena tent ech ee op ene one ae RN ga ne ee eh -20 25 10% discount in carton containing 12. 8774. Rubber Bulbs, of red non-blooming rubber, stout walled, for pipettes. CAaDAaClt ys, OUNCES e me isc ecb) pore eae, Norte wish Baek ane taint cs oe A oe fh i 3 3 Pen et hy AN Chess cet sess pears mean cate PEN eR BCH aS Ades AD ain Ree 14 13 23 Diameters IN Chess 46 ison t sete et! fda sna ih dunn ee nation non Genrer eeu anon an zt 14 13 SAAC Nee raat estan a et ck ee NA arene ere A ee OM dl et he ance lee 13 15 16 8776. Rubber Bulbs, of white composition rubber, large size for large pipettes, etc. Benothsincness: $c aka ute anAiie 2a tate yt ae een kel tenn byn 1) tobe the k oUl:h 4 335 4 AD IATME LET: II CMOS teat art retey hs beg sec enn entrar MRS Sek ore ley hte EA ap 3 18 1% BCI sii ue ck eos ree ge eat PG ra ee aes an nee Resse a rate gaa eM 21 22 25 8777. Rubber Bulb, with single valve, without extension tube, of gray rubber 23 inches long by 2 inches diam- EGET acer a ers ca ahs frase a nse rh ven Ream Ne ee pe ee Rd aA ed cea Oat Loe Ae oe oes rawr ghel lin Ape tg 28 A R T H U_R H. T H O M AS C O M P AN Y Ny : men | | : ‘i il 9% tt My ONg hay } : Hi i F = ” 8782 8778. Rubber Bulb, with two valves, of white rubber, with 5 inches of tubing......................... .40 8780. Rubber Bulb, of pure black gum, with long flexible tube, for use with gas analysis apparatus........ 75 8782. Rubber Bulb, with two valves, of hard rubber, giving the exhaust and pressure, i. é., the first compression of the bulb releases blast from one end, after which suction is produced from the opposite end, when the bulb resumes it usual shape. As used in gas analysis,etec............................ .75 8784. Rubber Bulb, double, of pure black gum, with heavy silk net, for constant pressure.............. 2.00 8786. Rubber Bulb, of black acid-cured rubber, with double valve set in bone AUTIN OS Ah erry eek ee ee 75 iii 8790 8791 8792 8793 8794 8788. Rubber Caps, with rolled edges, for covering tops of test tubes, cylinders, flasks, ete. : Diameter, inches........... 5 é 4 t 1 1+ 13 a 2 3 Per dozen................. 1.25 1.40 1.40 1.40 1.40 1.40 1.40 1.50 1.65 1.90 10% discount in cartons containing 144. 8790. Rubber Finger Cots, of pure gum, heavy weight. SIZ Carn rte Meer tte ay hier tsi Ve teat Ce ML Det MRA aREL pire aye ce Small Medium Large Thumb POP GOZOi a fiir Sees ee te ee yey haan es ae enn ta 15 15 75 75 i i bber tissue. a Seger oe ve e - ean : - . Led PHS eT Aan I OR Small Medium Large Thumb POR d OZER i405 hoe pt a ee eres eit ect yt iors Minted 30 -40 -40 -40 8792. Rubber Gloves, of pure gum, chocolate color, medium weight. Size No. 9 is required for normal male and. i 7 8 9 10 DIZON Giselle wee enon dates re woe eae ah Wine alas pee on na Pee DDAIT ie shind alo nelere pk aid ea scons than Ms het Ne cence eed tne L ays AL 1.10 1.10 1.10 1.50 8793. Rubber Gloves, of thinnest pure gum tissue, smooth finish, as used by surgeons. Sizes 64 to 9. ple SPeCiLy Size: When: OFGETIN Gers esas csscsici oes ae ea wide GN yO ba eg aon ae Ind eet HO Ae is ee Z 8794. Rubber Gloves, of heavy white rubber, so-called ‘‘acid gloves.”” Gloves measure 8} inches from tip of thumb to end of gauntlet. Sizes,9and10. Perpair........................0...0..... 3.75 ium-weight black rubber, with thin cotton lining and gauntlet. Widely used in is so tages Tomiie oid anette for post-mortem work, handling of pathological material, ete. S1Z68:- 9) COT e ROR: Palo see sczce seers ssus coast ee She cores ea cate anaes OsENG ae relate eo ee Mar ative 3.00 8798 8802 8796. Rubber Policemen, for washing down precipitates, narrow shape with glass rod. Rubber part is 3 by -80 HeinchilOnGee iP Cbd OLE sesh erctnr sees tue Peat, Sash ah arene ce Bo lenng A dmc VE SNe buen nee at 8797. Rubber Part, only, for No. 8796 Rubber Policemen. Per dozen...............0 00.02.00 e cee eee 50 8798. Rubber Policemen, wing shape, with glass rod. Rubber part is 1 by 1! inches long. Per dozen.. 1.05 8799. Rubber Part, only, for No. 8798 Rubber Policemen. Per dozen.....................00 0000005. 75 8800. Rubber Policemen, new shape, with glass rod. Rubber part is 1 by 1} inches long. Per dozen... .95 8801. Rubber Part, only, for No. 8800 Rubber Policemen. Per dozen................0.2..00 00 eee eee .65 6067. Glass Rods only, for above policemen, 6 inches long by 35-inch diameter. Per dozen............ 30 8802. Rubber Policemen, with hard rubber handle 71 by 3 inch and soft rubber cone-shaped tip } inch wide yea et Chill OT Decanter ane rien Reed SR oes ei Aa ete salt aN Sean cy Da Ex dial eA nih cht le de .30 8803. Rubber Tip only, for No. 8802 Rubber Policemen. Each.................0 00000 ce cece eens . 10 RUBBER STOPPERS 8810—(Exact size) 8811—(Exact size) 8812—(Exact size) RUBBER STOPPERS, A. H. T. Co., Special Quality, made of selected stock containing a large per cent of pure Para gum and distinctly superior to the stoppers ordinarily sold as pure gum. Each stopper bears our trade- mark. Specification as to size must be given with order. 8810. Rubber Stoppers, as described above, solid. Perlb........... 0.0.0.0 0c ccc eee 1.50 8811. ditto,;butsone hole: “Per Misc 222 ccn co rexe as A aeiees wo as Nas Wied Gade Aneotuot ee Becca esen pacers eoren 1.50 8812. By CW ORN OLS ot MOD MD ype hhe cee Duct pagar tyue Shirred CoA saa serice ease AAVe nh eee ah rae enc 1.50 10% discount in lots of 10 lbs. of one size or assorted. 20% = = oO OR a a “ 380% “cc “i “ee 6“ 50 “cc “cc “ce “ce 6“ “ec Table Showing Approximate Number of Rubber Stoppers No. 8810, 8811 and 8812 in One Pound Nun D6 iis Fa eis ate ener cess oie ne ep ene 00 0 1 2 8 4 5 6 7 8 9 10-11 12 18 | Diam. large end, mm................... 14 17 18 20 23 25 27 32 37 #41 #45 50 56 63 68 (eet Smal Semin sen aus tolun seine 9 12 15 16 18 20 23 26 30 33 387 42 48 538 61 | Approximate { SOMdi cons titan oe ee 120 80 60 55 42 33 28 20 15 12 11 8 6 5 4 number in ISHOLGY Gauss pen ere 130 90 65 60 45 35 30 21 16 13 11 8 6 5 4 | one pound [a hele oe te ree 134 94 70 64 47 38 32 22 17 14 12 8 6 5 4 | Approximate weight per 12 solid stoppers MOZS al eentaecer cs Bea cen red ely NNR 2 3 4 5 6 7 8 11 15 17 22 28 37 50 56 unc 32 MM-~~799- FR, Reon 27MM WA -~-= 26 MM---— pre eas ae --=20MM-- ‘ : 1 '06 : NOS 5 NO 4 S NOS No] = = 2 o a 3 % bocce: 26 MM_...--> : Sane eM Mas oS i 2 OIMIMan se i ----18MM.- -- ---1I5 MM. 8810 Rubber Stoppers—Exact sizes of some of most used numbers. 5382 A R TT H U R H. T H O M AS Gc OO: M FP A N Y 8814. Rubber Stoppers, exactly same quality as No. 8810, but new extra long shape. Solid. Perlb...... 1.50 8815. ditto, but 1 hole. Perlb............. Eh tear tua ies tg Rees hs eee ane e ea See tena 1.50 8816. ditto, but 2 holes. Perlb............... LP A SARS SLU ERE STUN LOTR FERG ONE TO eo Os 1.50 Table Showing Approximate Number of No. 8814, 8815 and 8816 Stoppers in One Pound | Number........... 3 ae ee eee a 20 21 22 #328 24 25 26 | | Diameter, largeend,mm................. te 22 25 26 28 30 34 40 | ee small ‘““ mm heer ee 17 19 20 22, 23 28 34 | Approximate ( Solid....................., ‘ 37 25 22 19 17 11 8 | number in MOLE aust Hy lence met ee ory er 38 26 23 20 18 12 8 | __one pound 2 holes ered eesce 40 27 24 21 18 12 8 | | Approximate weight per 12 solid stoppers, ozs 5 7 8 10 11 17 27 K----- 25MM ---- ----19 MM--- <--- 32 MM--- 77> <-- 32 MM----- 8814 Rubber Stoppers—Exact sizes of some of the most used numbers. 8820—(Exact size) 8821—(Exact size) 8822—(Exact size) 8820. Rubber Stopper, for use in the evolution method of determining sulphur, containing a minimum of sulphur in the composition. Furnished in No. 6 size only, with two holes. Average 20 to the pound. Per Liye re REE oe 2 een Soecttaae prudish me ae Win hth che Ge eas Hae tas Neue le pen Aur 3.20 8821. Rubber Stopper, for use in the official Brown Duvel Moisture Tester in glass flasks No. 5448. Made of a special composition to withstand high temperatures. See Bulletin No. 72, U. S. Bureau of Plant Industry. Size No. 5, one hole. Average 24 to the pound. Per Ib... 66 ces ne ees 3.00 8822. Rubber Stopper, Kjeldahl, specially designed for use with 500 ml Pyrex Kjeldahl Flasks; top diameter 32 mm, bottom diameter 26 mm, height 34 mm. The one-hole stoppers have a hole 8 mm diameter. They are made of the same special stock as our regular stoppers, and are carried in stock to meet the demands of fertilizer and other chemists conducting Kjeldahl determinations on alarge scale. Style... 0.0.0.0... 0.02 e cece teens Solid 1 hole PGE GOZGi. cries os hs ee oe eh Sf SLATS RES DRIES MONA Tm eae saad rio, 7 heZO 1.20 Rubber Tissue, or dental dam. Per sq.ft........-.-0---- 20s eee ee es BOR Da Aes tes poh Lat aia Ae 55 ANS UR. ES aU oR H. EH! © «Mi cA Ss G 0: M PP -A NY RUBBER TUBING Our Laboratory Rubber Tubing No. 8830 and No. 8831 F.S. Pure Gum Tubing No. 8834 and No. 8835, A. C. Pure Gum Tubing No. 8840 and Nitrometer Tubing No. 8842 are all made especially for laboratory use. All of this tubing is distinctly superior for laboratory purposes to the ordinary stock article current in the rubber trade and of similar appearance. Experience has taught us that only by establishing our own specifications, under which all of these tubings are made for us, is it possible to maintain a uniform and satisfactory quality. 8830 (Exact size) 8830. Rubber Tubing, Laboratory, thick wall. A white, hand-made, cloth-wrapped, flexible tubing guaranteed not to split and of great endurance when exposed to laboratory fumes. This tubing is made especially for us, is distinctly superior to the rubber trade stock article of similar appearance and each piece is marked with our trade-mark. The } x 4 inch is the standard size | for laboratory Bunsen burner connections. Bore, inches...............0. 00 ee eee 2 oy wes 3 a (Nee 3 1 Wall, inches...............000.0000. os, a a’ ae Mee es t e erst tie es era eee hatte airs era .07 09, AS / .18 | -.21 ae /30 35 AB 20% discount in cartons of 10 ft. 25% discount in Mae of 50 ft. 8831. Rubber Tubing, Laboratory, thin wall, of the same quality as No. 8830, but. with thinner walls. The 4 x js inch size is packed in 10 ft. lengths only. => BOT INCHES: wai-aaeavaaeaunh aire eteshad ion Wears - ae, ao bene Aare: 3 5 Wall, TICHOS hg citehs, cela hates ie Rt ee Oda ek te te te is s s POR fbi eee ate eae gh oe sot ok EE .05 -06 -07 -08 15 17 0% discount in cartons of 10 ft. 25% discount in cartons of 50 ft. 8834 (Exact size) 8834. Rubber Tubing, F. S. Pure Gum, thick wall. A seamless, hand-wrapped cloth impression tubing made of the finest grade of Para rubber and sulphur. This tubing is steam-cured and on this account is delivered with a slight ““bloom” and is of specific gravity 0.98, i. e., Floating Stock rubber. The hand-wrapping process makes the stock firm and eliminates porosity, while the curing on smooth mandrels makes the bore of the tubing absolutely.smooth. F. S. Pure Gum Tubing will last longer in laboratory work than acid-cured tubing and is_recommende lea for all laboratory work where the ealem sulphur content does not influence Ee X Bore, inches. . & o 4 \ 7 64 Wall, inches. . 08 12 15 25 30 35 / 5 20% discount in cartons of 10 ft. 25% discount in cartons of 25 ft. o cole a2 16 a is ai a 32 + 16 a Bt zs el aleo S| el colen SIH Oe Per fits: a. bhccee A 8835. Rubber Tubing, F. S. Pure Gum, thin wall, of the same quality as No. 8834, but with thinner walls. Borex inChess: weve safe adsars ees oaeed cools Mea wanton AR Gano aegin eens 37 ra t Weallisinthess.2cct. at. ae Atle a ee ieee eee ee ee ea er aa a er POR et tei oye hele ee erent: a Neenah aud RAT deka ean CA avai enema anaes 05 -06 -09 20% discount in cartons of 10 ft. A R T H UR H. To (HO. MA 3S G -O M P A N YY 8842—(Exact size) 8840. Rubber Tubing, A. C., Pure Gum, thick wall. Th’s tubing is made from semi-transparent, pure gum sheet and is in the natural color, i. e., without coloring material to make it either black or red. It is acid cured, i. e., without bloom, and is the best tubing obtainable for purposes in which an acid-cured bloomless stock is required. For convenience and economy it is packed in neat circular boxes containing 10 ft. lengths. Inside diameter, mm.................... Sie gael 3 4 5 6 8 Thickness: of wall) mmb. 2. cise ee ee es ee try oe pg 3 13 12 1? 2 Per foot, in less than original lengths................ 08 .08 12 15 .25 10% discount in cartons containing 10-ft. 8842. Rubber Tubing, Nitrometer, of grayish red rubber, specially made for use on nitrometers. Absolutely free from talc in the bore, nearly acid-proof, and retaining its flexibility and clinging quality for along time. Inside diameter } inch, wall ; inch. Per ft 10% discount in carton containing 25 ft. 25% discount in case containing 8 cartons, 7. e., 200 ft. 8844—(Exact size) 8844. Rubber Tubing, Pressure, of black semi-pure gum, very rigid to withstand heavy pressures. Recom- mended for use with filter pumps and similar connections. Inside diameter, inches................6-+0.00e 00005. t Ps 7 3 * Thickness of wall, inches..................0ee eee eaee z 5 vs i 3 POE fO0b 33 oo a er hE SIO RS 12 25 31 58 75 25% discount in cartons of 50 ft. 8846 8850 8846. Rubber Tubing, for Gooch Crucibles, so-called “band” tubing, very elastic. The inside diameter given ig when measured in cylindrical shape, i.¢., in position as used on crucible, and outside diameter is when measured flat. Inside diameter (cylindrical), inches.........-- +--+ 0-020 e sree 3 1 1 1 Outside diameter (flat), inches... .......... 2.0000 eee eee reese 1 13 a 13 POE LOO bis alee ee LE eR SE a a aan aaa lect atta eee 18 23 24 28 8848. Rubber Tubing, Haemacytometer, of pure gum. Specially made of correct size, thickness of wall and quality for this purpose. i Par fo Otsi ek se tee ocd Geatscar Beas dishes naan Rsocar ee tenuate ter ana ban a ay Naser ee Oy ee é 8850. Rubber Tubing Stretcher, for increasing bore of tubing for conveniently slipping over sonner Hon bales: (ChOs cig cage wn das ace axe ey bog POUR ERE ee NARI ETE EA ESR ere E Peer eta I 8860. 8861. 8864. 8865. 8866. 8867. 8870. 2850. 8872. 8874. 8876. 8877. 8867 8874 8876 8877 Samplers, Jones, for convenient, rapid and uniform sampling of ores, cement, etc., consisting of a hopper, scoop, four sampling pans and brush. All parts may be readily cleaned. SIZE INCHES se sens cea Manat s acatiie pit cop ich Ma lak Sik! Mian nahn iat die 4x4 6x6 8x10 Width of trough; inches). coc sees oes es tas hee Ure Moai teenie Ap 3 3 3 ACh eRe TE SUL etd te ISRO AT ean ke ie es 17.00 23.25 30.00 Sampler, with scoop; 6 inches square with divisions } inch wide................... 00002000000 4.35 Sand Baths, deep form of sheet iron. Diameter, inches................ 3 4 5 6 7 8 10 PACW. Coe Rie es eee Oo 10 -10 18 aoe .35 -40 .85 10% discount in lots of 10. 20% discount in lots of 100. ditto, but shallow form. Diameter, TNICHOSiicccc8 5 tees seas aay 3 4 5 6 7 8 10 ROR seg cate SR wae. SH ane 8 10 -10 “15 18 .25 -30 -60 10% discount in lots of 10. 20% discount in lots of 100. Sand Bath, or Hot Plate, of cast iron, with burner adjustable for height; size 11x 17}inches...... 19.20 Sand Baths, or Hot Plates, of iron, without burner. GigeninGhess: cdsrcnc tess oe Faved tees ke Ge eA aL On pte Ree ee ey atte 6x8 8x10 10x12 ache eter ett ae nis etn en aa tone a ERE ri aye RACE “2.00 2.80 3.45 Sand Glasses, in polished wooden frame. Time, minutes..... 3 1 2 3 5 10 30 60 AGN 5 ick eee ness 20 .20 25 25 .25 35 75 1.50 2.00 Schaelchen, Hofmeister, of very thin glass, about 2} inches diameter, as used in organic analysis .... 10 Scoeps, Counterpoised, for use as weighing-dishes, etc., see No. 4538, etc. Scoops, of horn, shallow form with handle. Agere thts ee ene een ee eres th Paces ete yee ree ae ee ACO hal 100 120 140 160 Ms eo ee ek ao ich st AL Be wee HE re eta 25 .30 .35 .40 Scoops, of horn, deep form without handle. Tren cthemmece eis een Ge BS oe a eas Runes aoe ct . 60 80 100 150 Each. ; Wout Se Rheroa nO: 25 .35 60 Scoops, Weighing, of glass: allow Tourn ith flat batten, Tuerigths inches: sc .aveso suena ian ooh iean ame g Ah ayes eave aerate Paty oan Cn er ee 23 33 DRE A ps eo pee 5 oar ee ee ine et an wag con edn aed SV creases stale a 35 50 Scoops, Weighing, of glass, deep form with flat bottom. Tene tn AN CHES, ee wie fata rcleer Cle dy sia temesleona Cone lstny Sante outta alecitn he erat hore 4 3 BCI sco iecek sa eee ps Scans Selon ei ede av an tn Meson Ne cade eh native ahaa Bas 35 50 8878. Scorifiers, Denver Fire Clay, regular shape, guaranteed not to crack in process, or to pit or leave any opening for retention of lead after completion. Diameter, inches.......................... Rene eileen ks 2 2t 2h 38 Per 100... Chee ne eee eee (ieee: 868 380 435 5.70 10% discount in original barrel containing... PERE es Gs nee 2000 2000 1750 900 8880 8882 8880. Screw Driver, watchmaker’s, nickel plated, very convenient in the laboratory for use on optical and other instruments; 5 inches long.................. renee Ms sty epteak rane erg! De Se 50 8881. Screw Drivers, as above, set of four sizes, i. e., 33, 4, 43 and 5 inches long. Perset...... same, ©2200 8882. Screw Driver, optician’s, 3 inches long, with three blades, large, medium and small.............. 1.30 a3 s 4 7, £& .¢> ull | \ i il AT aN eM x 8890 a 8895 SHAKING APPARATUS, International. A heavy, substantial machine with an ingenious combina- tion of journal and ball bearings yielding a smooth translation of rotary into vibratory motion. The vibration is elliptical with the longer axis vertical, and the amplitude is about 14 inches. The result is a vigorous batter- ing of contents of the containers, reducing it to a fine division. The machine is regularly furnished with a 4-bottle head with adjustable clamps, or a Rickards 24 Sputum Bottle Head. The 4-bottle head takes ordinary bottles varying in capacity from 200 to 1000 ml. Smaller bottles or tubes may be conveniently held by fitting necessary blocks. This head can be rotated at from 400 to 600 r.p.m. with small bottles, and 300 r.p.m. with 1000-ml bottles. The Rickards 24 Sputum Bottle Head (see Journal of Infectious Diseases, 1907, Sup. No. 3; and Science, April 8, 1909) provides for the examination of sputum where many samples are to be examined daily, and each sample must be rigorously inspected. The bottles used are the small bottles in which the sputum is collected, so that the danger of confusion of samples and of, infection when removing contents of collection bottle to shaker bottle is eliminated. The sputum, by vigorous shaking, is thoroughly and uniformly broken up. This makes possible a satisfactory even smear on the microscope slide, thick enough to present a fair sample of the particular specimen under observation, yet not so thick as to obscure light and thus jeopardize the chances of finding the organisms if present. This head may be operated at about 600 r.p.m. i ; , As these Heads are interchangeable, a very complete Shaking Outfit is to be had by purchasing either machine with either a Four-Bottle Head or a Rickards 24 Sputum Bottle Head as an extra part. 8890. Shaking Apparatus, International, with 4-bottle head, as described above, without bottles. For 110-volt c Ie a Pe Ett ete PN Nae NAL Lote TONE ASRS oP ee OA EMO Tr PARI ON on 165.00 8891. ditto; but for 220-VOlt;:d.@ss 5.0 o...0c es nie Pee Bas 6 Oe Rae OEM ae abe gE i _... 167.00 8892. ditto, but for 110-volt, 60-cycle, a.c.......0.0..00 006. eee Reheat A ect aah tae . 165.00 8893. ditto, but for 220-volt, 60-cycle, a.c........... 000.0002. ae tore 8894: <4-Bottle Head only. <3 sss fae ihe $22 bese trad Meena Gees Eee g Nee mieha 8895. Shaking Apparatus, International, with Rickards 24 Sputum Bottle Head, as above described, without Bottless Hor’ UlO=volts dics tas cede anette Guten cere en ocd we MAM BIRR aetea aba aEainn aes 165.00 8896. ditto; butfor:220-Volt, Chics notin are meee See ee ieee Gah eae RaSh Sagcobataee on ec 167.00 8897. ditto, but for 110-volt, 60-cycle, a.c.. 0.066. ete ee beens 165.00 8898. ditto, but for 220-volt, 60-cycle, a.c.......00 0.0 c ees ee 8899. Rickards 24 Sputum Bottle Head only........... 0-5-0... eee eee 8906. 8907. 8908. 8909. 8912. 8913. ‘ Ae | \ ie 8906 8908 8909 Shaking Apparatus, C. S. & E. A new device directly driven by electric motor with friction clutch adjustable for eccentricity, so that the speed of the shaking can be varied from almost nothing to a violent up and down motion. The holder regularly supplied with each outfit takes three 4-oz. wide mouth bottles. This holder is quickly interchangeable with holders for test tubes or holder for 500-ml flask or bottle, both of which are listed below. Complete with three 4-0z. wide mouth bottles, cord and plug for 110-volt, 60-cycle, a.c... 00.0 eee 130.00 IEEOs? DUGAtOrs ML O=ViG HG isha setae vers foresee nc Sire ri atsou at sect sieeh ttehence naa dpzsy nice rea ebeg cba Poe a ae SoA 130.00 Test Tube Holder, only, for above Shaking Apparatus. Takes six 150 x 18 mm test tubes, and is inter- changeable with the three-bottle holder regularly supplied with the machine. Complete with six test:tubestand wiulb ber:stoppersirac «4 ince sea neacomaet a = ae, GAMA ean cas eaeasina oaaia lesa tke 15.00 Flask Holder, only, for above Shaking Apparatus. Takes a 500-ml flask or 1000 ml bottle and is inter- changeable with the three-bottle holder regularly supplied with the machine. Complete with one 1000:ml-bottle-and rubberstoppers:: 2.2. sixes Eee ee etn ees en ee Be ow de ee 10.00 = t ( or ! Hifi ‘= LH Litgy iam ln ny Aaa a a pe - ; — 8912 : 8913 Shaking Apparatus, Steel Laboratory Model, of the type as originally suggested by Camp; particularly suited for the rapid precipitation of phosphorous by the molybdic method, and dissolving steels or pig-iron for carbon combustion. Made to hold 6 flasks from 6 to 24 ounces; pulley, 6 inches in diameter; power required, about ;; h.p. Can be operated by small electric motor with suitable countershaft to control speed, or by direct connection to a water motor. Without motor... 30.00 Shaking Apparatus, Sugar Laboratory Model, same as above, but with wooden disc and clamps to accom- modate twelve: dO0im) sugar faskss | in 3. cc. fi 5x alters Sass ean clniged Soked sue paw ie 45.00 pee 8920 8916. Shaking Apparatus. A most convenient form for a great variety of laboratory work. The carriage con- sists of a wooden box 15 inches long by 9 inches wide by 6 inches deep. Bottles and flasks are held in place by packing with cotton or scraps of paper. The carriage travels back and forth quietly, and seven different variations are possible in the length of the excursion. The moving parts of the apparatus are rigidly held in place by a metal frame and base. With 1-inch grooved pulley, but Without mOtons Sc: Geers eta a 8 learned coat dual area aNamne eetas a Reet Sak Sere eee aes 36.00 8917. ditto, but with motor for 110-volt, d.c....... 0.0000 ee Se Cem Wi ahs pel aac tea 60.00 8918. rn wee fo 1DO=VOlt, G0=CY cley AsO sc cia: cvee chee ee heen eG ARE RES A oS 60.00 8920. Shaking Apparatus, designed to meet the need in laboratories where only small amounts of material are to be handled, and with particular reference to shaking of haemacytometer pipettes with a rocking motion similar to that used when the pipettes are shaken by hand. By means of a rheostat the motion can be regulated from a very slow gentle rock to violent agitation. The pipette holder takes four haemacytometer pipettes, which can be conveniently inserted and removed without danger of breakage. A pair of clamps can be quickly added to hold a 250-ml Erlenmeyer flask, and an additional holder can be used in the same way for two 2-oz. wide mouth bottles, as shown in illustration. Test Tubes up to 120 mm long can be used in place of the haemacytometer pipette. The motor is universal, operating equally well on 110-volt, d.c., or 110-volt, 60-cycle, a.¢. circuits. In general design, with particular reference to the shaking of haemacytometer pipettes, this machine follows the suggestions of Dr. Russell L. Haden, A Machine for Shaking Blood Counting Pipettes, The Journal of Laboratory and Clinical Medicine, V, 10 (1920). Complete with rheostat, clamps for Erlenmeyer flask and bottle holder as shown in illustration......................--. 75.00 (TE 8932 8930. Shears, for cloth, with nickeled blades and handles. ‘ : * +s Total pene ene es : 3° n u 2 cutting edge, inches.........----+ essere 4 4 x ea Bhouae a ean vine eee atone, wade rene anata 135. 1.70 2.20 3.15 8931. Shears, strong and heavy, with short blades, for general laboratory use; total length 8} inches, length of cutting edge, 23 inches......... Gai eag ine oat ‘ - eset tpi cleesee ate Nee aie ae Ca ee 8932. Shears, Tinner’s, for cutting metal and wire. Total length, inches....... nae ss i i Length of cutting edge, inches......---+------0t sss ttt Fin G isos seco aatostan oe: ad Racca aw aay Tes Anat nee apr esa pe SE AE ee Cee a ee 10 20 40 60 80 —-100 8940. Each, : ee ae AS fondle eee ri reve we 3 ay oe EM ve au 8941. Each, 8 inches diameter.....--------- +0 3 A 5 8942. Each, 12 inches diameter........----+ +--+ > 1.15 1.35 1.60 2.00 2.60 3.75 i ing in diameter from 53 to 8 inches, with brass gauze and tin frame, in accordance ar Siete Nee eo “thé American Society of Civil Engineers. Eight in set consisting of one each 10, 20, 30, 40, 50, 80, 100 and 200 mesh. Per set..........-.00 20sec cree e eens 50.00 539 A R T H U_ R ELS T H O M A S G02) GM> Ps Aw Ne oy 8948 8950 Sieves, Brass Gauze, with Brass Frame, without cover or receiver. IVES hips eeepc iat or crane cheered 10 20 40 60 80 100 200 8946. Each, 5 inches diameter........... 1.70 1.70 1.80 2.10 2.20 2.25 4.70 8947. Each, 8 inches diameter........... 2.85 2.90 3.15 3.35 3.40 3.40 8.00 8948. Cover and Receiver, for above sieves. For, diameter, inches................... es 5 8 POP Setsof One veges ton 0) 8 hoteles ciel a aimee pst a eaten OR ele a BE engin oaths 1.50 1.85 8950. Sieves, Brass, in nest of five, 20, 40, 60, 80 and 100 mesh, with cover and receiver. Diameter, inches....... onan gaan Gains wen Les AUa Ba yh caus native te Teast ss 5 8 PGR NCSU joi aoe cheer cae ae cop ee ER AE EN ce SAME BESTS da ea OOH aEsP) tito OE 11.55 18.45 8952. Sieves, Tyler Standard, 8 inches diameter, with seamless brass frame and with specially woven brass cloth absolutely square in mesh and made from the same gauge wire both ways. The Bureau of Standards has standardized the 200-mesh sieve made from .0021-inch wire, having an opening of .0029 inch, and this sieve has been adopted as the base of the Tyler Standard Screen Scale. The ratio between the different sizes of the screen scale has been taken as 1.414, or the square root of 2 so that beginning with the 200-mesh sieve, the diameter of each successive opening is exactly 1. 414 times the opening in the previous sieve. The area of each successive opening in the scale is just double that of the next finer, or half that of the next coarser sieve. Mesh. tons ee See eee 20 30 35 40 45 50 60 70 Opening, inches : : .0340 .0198 .0176 .0150 .0127 .0110 .0087 .0073 AMM 2 cece ne Aes (hee 864 .503 .447 .3881 .823 .279 .221 .185 Diameter of wire, inches... . Areas .016 .01385 .011 .010 .0095 .009 .008 .007 Bachin. © 25 east nN ; ee . $3.60 3.60 3.60 3.60 3.90 3.90 3.90 4.10 Mesh. J eehione? : : 80 90 100 110 120 1380 140 150 Opening, inches. : ; ... 0068 .0059 .0055 .0051 .0046 .0043 .0042 .0041 TMM. + nc Sate ee ... .173 .150 .140 .130 .117 .109 .107 .104 Diameter of wire, inches... .. .00575 .00525 .0045 .004 .0037 .0034 .0029 .0026 Bache cc3.204<2s ee eee .. 445 4.80 5.20 5.35 5.50 5.95 6.25 6.60 Mesh......... eet er ‘ 160 170 180 190 200 220 240 8 300 Opening, inches . : : -0038 .0035 .0033 .0031 .0029 .0028 .0026 .0017 mm. : : . 096 .089 .084 .079 .074 .071 .066 .043 Diameter of wire, ‘inches. ....... 0025 .0024 .0023 .0022 .0021 .0017 .0016 .0016 POAC os eect A AS SEA Ca 7.00 7.70 8.40 8.80 9.15 9.85 11.40 15.00 $953. Cover and Receiver, of brass, for use with No. 8952 Sieves. Per set of one each................ 3.00 8954. Sieve, Tyler Standard Cement, No. 100, made in accordance with Bureau of Standards specifications, with seamless brass frame and brass gauze. The frame is 8 inches diameter by 22 inches high, provided with a cover and a pan 2 inches deep. The sieve has 100 wires per inch of .0045-inch CVATINC COTE esi csp vece resem ctotrses: ve nse Gate eco Ce ee Matis cael see sans Conse ENO neon AMG EAE pereore toe TA ep apen see ee 10.00 8956. Sieves, Cement, of brass, 8 inches diameter, 23 inches high, 200 mesh, with 200 wires per inch of .0021- inch diameter. Checked against a 200-mesh certified sieve, and furnished with a correction Hf ACEO Rs tehe recs eee caste pone wen Nae cok Gy wrem A ace ae pee ea hr fines Od oy Mig Sans Mek ot Rare share tank Maur Se eae fs 9.60 8960. Sieves, Brass, with seamless brass frame, 5 inches diameter, with circular perforations i in bottom. Size of perforations, mm... : See tate ie 3 1 2 Bla Clee sersee ceca ets oe ae iF eee Ne enced a NN antes ed 2.20 2.10 1.95 1.85 1.75 8961. Sieves, Brass, in set of five, as described under No. 8960. One each 3, 1, 2, 3, and 5 mm, with cover and POCOLV. Eloy 2h CLASOU perrris Sstn tea Aree prety res gee paren (Daron Aeaecaet Sheesh dt Jatin he LenaNG Sm mula Ne A 11.85 8962. Cover and Receiver only, of brass, 5 inches diameter, for use with No. 8960 Sieves, and as furnished with No: 8961. Sieves.. Periset-of one each «2 22.5.0 00h5 6 sonc Savane ales wladuntce caida she an nea ee eeeess 2.00 A R T H U R H. T H O M A S CO ME eR AD NY OY wii i 8972. Sieve Shaker, Per Se, taking standard 8-inch sieves, for power or hand driving; as used in sieving rice, drugs, emery, corundum, fire clay, litharge, silica, sulphur, cement, phosphates, pigments, sugar, gunpowder, guano, whiting, salt, starch, flour, linseed, cottonseed, boneblack, etc. The mechanical motion secured in these shakers is an eccentric, semi-rotary motion with a vertical drop. The sharp vertical drop or jog has been found very necessary in order to free the meshes from those particles which would ordinarily remain in the apertures of the cloth and to which in a great measure the efficiency of the device may be ascribed. These movements simulate very closely those obtained in hand manipulation of individual screens and the results secured show very close agreement between hand and the mechanical method. The machines are mounted on solid base with firm clamping device for the sieves. With pulley for power driving, and crank for hand driving, as shown in the illustration. Without sieves...........-..- 005-0 e eee een e renee 175.00 8974. Sieve Shaking Apparatus, for use with either hand or power; on wooden base 11 by 20 inches; height over all, 17 inches. Will take from one to four sieves. For sieves, diameter, inches.............05 2000-20 e eet e eee eens 5 6 8 | ET) en I Pe aia CTR or on eee Pa racer a hea ceria Sree aa a . 41.60 41.60 41.60 8980. Silica Rod, Transparent, in 12-inch lengths. Diameter, MM-c20s «ss soo sde ee aes RENE SF Peta ees me ES pea oath we es 1 3 ACH ee a OI ig te agnor Saray Re See 4 ; 50 1.25 8981. Silica Tubing, Transparent. Inside diameter, mm.........---- 5.0002 seers ... 1to1.5 1 to 1.5 3 3 Outside diameter, mm............----- See —.... 8t05.5 38 to 5.5 7 7 Length, inches...........5:-.05 50 se serene Seite onete 12 24 12 24 PACH onc hectare aoa hop tes RE a ee ee erate 1.00 2.00 1.90 3.80 8982. Silica Capillary Tubing, Transparent, with a bore of about 1 mm, outside diameter, 2 mm. Per foot.. 3.00 Silica Rod, Opaque, is manufactured in lengths up to 36 inches, and in diameters from 7; to 3 inches; and Transparent Silica Rod in lengths up to 24 inches, and in diameters from 7; to 7g inches. Silica Tubing, Opaque, satin surface, is manufactured in lengths up to 10 feet, and in bores from az to 2 inches, with thin, medium, or heavy wall. The sand surface tubing is manufactured in lengths up to 10 feet, and bores from 7’; to 43 inches. Transparent Silica Tubing is manufactured in lengths up to 60 inches and bores from 2; to 2 inches; lengths up to 42 inches with bores from 7 to +4 inches; lengths up to 24 inches with bores of 7 and 1 inch; lengths up to 18 inches with 1,3; inch bore; lengths up to 16 inches with bores from 2 to3 inches; lengths up to 12 inches with bores from 31 to 4 inches. | Because of the great variety of requirements, this rod and tu promptly from the manufacturers on special order. Silica Combustion Tubes, Opaque, are carried in stock and are listed under Nos. 3884, 3885 and 3886. 541 bing is not carried in stock but is obtainable 8986. 8987. 4880. H U R H. T H O M A S Cc 'O -M P A N Y aa ee a — 6 eee _ 2 —— 20 ° 6 9 bhi Ctmitsm diel eal fev Hu! daslodlal = i a aT Hy Auta B61 TE 910 40. : ohn htdbted wleok SEPP ep rr pe Te] Slide Rule, Mannheim Type, modified for calculation of urea index and sodium chloride formula. Adjust- able, 10 inches long, engine divided, divisions on white facings, with frameless glass indicator, in sewed leather case, with directions. See Journal of Experimental Medicine, 22: 212 (1915). 10.00 PETC Cen Ra ren 8987—Back Slide Rule, Duplex, designed to adapt the logarithmic and cologarithmic scales to the rapid solution of the problems encountered by the chemist. The symbols on the rule, being arranged in the order of their molecular weight, are easily found, while the application of a very simple rule enables the chemist to locate other symbols of less frequent occurrence. The rule carries 138 chemical symbols which include the common acids, bases, salts, oxides, and elements. As each symbol has its individual position corresponding to the logarithm of its molecular weight, the number of permutations and combinations possible covers the requirements of almost any problem. By using the logarithmic and cologarithmic scales in conjunction with the chemical gauge points, problems in Stoichiometry, such as gravimetric analysis, volumetric analysis, equivalents, percentage composition, conversion factors, volume of gas from a given weight of substance at different tem- peratures and pressures, and many other analogous problems are readily solved. The rule is ac- companied by a manual giving the theory of its use, together with numerous examples of both an arithmetical and chemical nature. Length 10 inches, engine divided, divisions on white facings, glass indicator, in morocco-covered case, with directions................ 0000s e eee eens 10.00 Corresponding Values of p, and Cy. for any p, Interval 4880—Front 4880—Back Slide Rule (Hydrogen-ion Calculator), L.& N. A specially devised slide rule, by means of which voltage readings at 25° C between a calomel electrode and a hydrogen electrode are easily converted into the corresponding pH or Ch+ value of the solution under test. It is based on the relation V=v +.0591 pH, in which V is the observed voltage, and v the potential difference between the calomel cell used in the measurement and a hydrogen electrode in a normal solution of H+. The values of v for saturated, normal and tenth-normal electrodes are marked on the voltage scale. The caleu- lator is correct for a temperature of 25° C. It is neatly made of celluloid, with directions for oper- ation printed thereon, and on the back of the calculator are tables giving the corresponding values of pH and CH-+ for any pH interval, by means of which more exact values of CH+ can be obtained than the H-ion scale of the calculator; and also a table of approximate pH and CH+ values of common solutions; and of the Clark & Lubs set of Indicators for the colorimetric determination of hy drogen=ton: concentrations: jaja sev. dees a aie ose hoe sunset aha Mapes Oe ae Rs ee eN ae Lee ee aS 50 Slide Rules, Richmond, see Milk Testing Apparatus, page 453. 542 A R T H U R H. T H O M A S Cc O M P A N Y Soap, Green, a soft soap of potash base with strongly detergent properties. Widely used for antiseptic purposes in connection with surgical and bacteriological work. Useful for many purposes around the chemical laboratory, such as cleaning glass and porcelain, desk tops, sinks, stained hands, etc. In concentrated form, for solution in water. Per Vian ce eee ie aes aay Oe Scr a EL Oe ea ape 53 Pees Ga ee Ww AMAT CO. | 8990 4429. Sodium Spoon, with brass gauze bowl with cover and with wooden handle.............-.-..-+45 55 8992. 8994. 8996. 8997. 8998. 9000. 9001. 9002. 9003. 9004. 9006. Sodium Spoon, with ramrod and tube mounted on handle ann 8996 Spatula, Glass, 6 inches long, with flat ground blade § inch wide..........---.---.-++ 0-00: dee .25 Spatulas, Horn, Double, with spatula on each end. Length,mm.... 100 120 150 200 Bea Chis ic tod ioscan mie: + aa Sera Poe Rate pe rnc eat Sone -20 .25 28 00 Spatulas, Glazed Porcelain, Double, with spatula on each end. Length, MM... 2.2... eee eee ee nee teen eee bent e ese r ete 120 150 195 Ba CH ek onc A A Sapa Sar es ae Nine cee Monee arts) DP Epi ene 43 50 -66 Spatulas, Glazed Porcelain, with spatula at one end and knob at other end. Length, Mm. cece yen he eee eee See a wae utara ee eee ‘ 200 310 442 aC haices besa ee ces oe eee eT ee tn et eee RE 74 1.32 3.18 Spatulas, Steel, very flexible, with cocoa wood handle. Length of blade, inches.... 3 4 5 6 7 8 10 12 Hach. eee 8 50 55 .60 .70 75 1.00 1.75 3.00 10% discount in cartons containing 12. 20% discount in lots of 12 cartons. Spatulas, Stainless Steel, similar to preceding number, with cocoa-wood handle but with blade made of stainless steel, recommended for all laboratory work because of its non-corrosive and non-rust- 6 ing properties. Length of blade, inches............-0eeee eee e neers 3 4 5 Bagh ses sues ase are a hn eRe a oa a ee Been oe ea oe? .90 1.00 1.10 1.30 Spatulas, Steel, with nickel-plated steel handle. Length of blade, inches......-.---+-+++serereeeees 3 4 5 6 8 Ba chis vc. ob cents) ieee eae Dee ee eS 75 -80 -90 1.00 1.30 10% discount in cartons containing 12. 20% discount in lots of 12 cartons. Spatula, Steel, with very flexible narrow blade and blackwood handle. Very convenient for weighing. Length of blade, inches......-.--.+-seseerer teeter er set sees 3 4 5 a OH es fer eek oe ae ea eee eee Seer aR aE ag -50 -70 15 -95 10% discount in cartons containing 12. 20% discount in lots of 12 cartons. Spatula, short form with wide blade, so called “Pill Knife,” of steel with blackwood handle. Length of -70 blade, 34 inches......-----+-:-seryne te agen an errr ere ee ee 10% discount in cartons containing 12. 20% discount in lots of 12 cartons. Spatula, folding form, i.e., like pocket knife; with thin flexible steel blade 3 inch wide and 3 inches long, i .20 in cocoa wood handle; very convenient for carrying in the POCKCE. vs cs ces saa aoe Hees 1.2 10% discount in cartons containing 12. 20% discount in lots of 12 cartons. Spatula, Hard Rubber, throughout, with very thin flexible blade. Length, inches... 4 6 8 Ba CWS oeeereses eet see ee ee PR eT eae ee as -40 50 75 10% discount in cartons containing 12. 20% discount in lots of 12 cartons. 543 és F il f' 9010 9011 9012 : 9014 9010. Specific Gravity Bottles, Gay-Lussac, unadjusted, i. e., for calibration in the laboratory. With perforated stopper. Capacity, ml........... 1 2 5 10 25 50 100 itchiness Ae cea oa tne rate A .30 .30 .30 -40 45 55 -65 9011. ditto, but with volume accurately adjusted. Capacity, Mss ec eel See SN 1 2 5 10 25 50 100 a chisiteianened a aeiciaee senator oes n te .60 -60 -60 -70 15 1.10 1.20 9012. Specific Gravity Bottle, consisting of Bottle No. 9011 with the addition of tin case and tare weight. aa EM bce grat each tiene sarees ore N US rotate mr stern Siri Mts eh nts tas, he 2 Cen VR es 25 50 PC ies is i eg ae hat A anes RE Meee es A cp ale arent Re ern oedema age sa RA 1.50 2.00 9013. Specific Gravity Bottles, new conical shape, with thermometer reading to 4° ground into neck. Capacitys- Mls ie alee inn Me me iattatiny ek elector Seat a at el otek oe ndash °10 25 50 100 MVOC ety essay Seca hang cpesy tack ran aa een k Deg encima CID An ae tons Re aks Be 2.75 3.00 3.50 4.00 9014. Specific Gravity Bottle, Boot, double wall with vacuum space between walls, and with ground cap. For constant temperature work. With volume accurately adjusted. Capacity, ml.... 25 50 BURCH hoes eaten ees MS stile Gos Suk Sip ro where oa ea eROR seoys Rae tren Bays core a Herman heer aera 8 cade 3.00 3.50 9015. Specific Gravity Bottle, Kohl, with thermometer ground in the side tubulation and with capillary tube ground in the central tubulation and divided in millimeters. With volume accurately adjusted. 3.50 9018 9022, 9023 9018. Specific Gravity Bottles, Regnault, for liquids. With ground-in stopper, and with volume accurately adjusted. -Capacitysaml. 2.2 e vice arid d ce hedge Ral aoe aS ee eee ten wa eed 25 50 9026 Bai esis eee ice es ast rt ates ater Wa aes i as AS aoe ee Pel mire ay ame acne ON at hen -60 90 9019. ditto, but without adjustment for volume, i. e., for calibration in the laboratory. Capacity mil... aa) cose sh ennta cera eek ces chah eal meatier na Rial aminn| scan eave tial 25 50 AC i ae psa tote ee aes gn pe Rade ee Ea Coe a SNE RN ne ea -40 -65 9020. Specific Gravity Bottles, Regnault, for solids, with ground-in stopper and capillary ground into neck of flask. With volume accurately adjusted. Capacity, ml....................... 25 50 WAC Satna canes iG Riluamudaeeeica chee mies Oh tay ae reuauet aac see yuna d a caeeaet rae .80 1.00 9021. ditto, but without adjustment for volume, 7. e., for calibration in the laboratory. GAA Clit Weer i ams sake cata Gorter recs seee hs Ome coke ae ota peepee eat Ree A EUT 25 50 SAC teeters seca ieee hc te shatentyrian ain a ba cw aurstes kNne feu eT ONG Hesleci th aee hab aaa La Fen es rat nal eee -60 -80 9022. Specific Gravity Bottles, Reischauer, with ground-in glass stopper and separate funnel tube for convenient filling. With volume accurately adjusted. Capacity, ml.............. 25 50 100 ACT eee ee ore em RU MTL Sh aed oe een nea te 1.10 1.35 1.60 9023. ditto, but with millimeter divisions on neck. Capacity, ml............... 25 50 100 a Ch ie: ene see at a es ee ste naes mets ee se aes Oper Nana hake anc hla AR 1.60 1.85 2.10 9024. Specific Gravity Bottle, Reischauer-Brinton, without adjustment for volume, i. e., for calibration in the laboratory. Consists of a 100-ml glass-stoppered flask with special narrow neck so made that the 100-ml mark falls low on neck. Empty flask with stopper weighs from 18 to 20 grams. Inside diameter of neck is 6 mm. See Journal of the American Pharmaceutical Association, August, FI eS aa te ee RA ES ES EF Ee aT ee on ee 1.50 9026. Specific Gravity Bottle, Nicol Tube form, for liquids, 5-ml capacity. Without adjustment for volume, 4 (M. AS Cc Oo 9170. 9171. 9172. 3010. 3011. 9180. 9182. 9183. 9184. 9191. 9192. 9193. ae t = = 9170 ; 9172 9184 Support Stand, for Nos. 9164 and 9165 Absorption Cells, consisting of round base, rod, extension clamp and holder provided with 150-mm rod; also suitable for use with Reading Telescopes...... 3.35 Support for Spectrum Tubes. Will accommodate tubes up to 250 mm long..................... 5.00 Support for Spark Terminals. The clips for holding electrodes are readily adjusted and well insulated. 7.50 Speed Indicator, Dial Form, in nickel-plated case, with enameled dial and rubber tips for pointed or flat centers. Very convenient for determining the speed of centrifuges and other laboratory apparatus. Reads*up:toi30;000:repsma carers fe erence cheread hone st aie 3 al (Pama ter ele cued Psa aici ys) CDAD) Speed Indicator, with graduations showing every revolution, and two rows of figures reading both right and left as shaft may run. While looking at the watch, each 100 revolutions may be counted by allowing the oval-headed pin on the revolving disc to pass under the thumb as the instrument is pressed to its work. Nickel plated, with hard rubber handle, hardened steel pointed spindle and rubber tips for pointed and centered shafts.............0.0 0.000 e ce eee 1.85 Sponges, for laboratory use. Average about 14 to the pound. Perlb........................... 1.50 Spoons, Horn. Length,mm..................... 100 120 150 200 240 300 ACh ea see ee ae eS tess -10 «22 32 48 .65 75 ditto, with spatula end. Length, mm eee 100 120 150 200 240 300 ACh ee cssets re A atid rec rte bins Ghee -26 32 38 -60 1.00 1.75 Spoons, Glazed, Porcelain, with spatula end. 96 120 140 160 Weenethy mimesis aes 8 poke wart Seg aaah tek tae ene tee heme 9191 9192 9193 A heavy, green glass bottle, 2 inches high and_1 inch diameter, for mailing sputum les inside of mailing tubes as required by the U.S. Post Office Department. Wisely 15% discount in original case containing 7 gross. ditto, but with corks to fit tight. Per gross... 20.6.2... 26nd 7.25 15% discount in original case containing 7 gross. Sputum Bottles. and other samp. 1 used in Board of Health work. Without corks. Per gross...................---2.00555 with extra long cork; as used in Trunnion Cup No. 3103 on Inter- ttle, square, 10-ml capacity, SE al Size 2 Centrifuge and in Shaker Heads Nos. 3046 and 3099. Per dozen........... 85 Per gross............ 9.25 ini i lass, for staining specimens on the slide; consisting of a rectangular glass box with Se ee tray nea nickel spring wire holder for lifting tray out of staining solution in box. Will take twenty slides 3 x 1 inches, 3 x 13 inches and 3 x 2 inches. Complete with eles dish, removable tray and wire holder 50 Glass Dish, only, for above nie pate fibres Cae ete a metres eeu a cr eben nile ee aawcileins feck amr a een a aes ae Cinna rag oo) ee phew ome oie ae Hane aT Sat Cees eee RES i Nickel Wire Holder, only, for above My WN, "ONT ‘ il rn Miia KO ‘i we i, ' i Mi uaa = = _ He hincmnl " ‘al Coin - It a = =] Gn | a 9212, 9214, 9215 9220 9194. Staining Dish, of glass, for staining specimens on the slide, with loose fitting cover and grooves to keep slides in place. Inside dimensions, 75 mm long by 58 mm wide; capacity, 10 slides of varying aes 45 0% discount in case containing 15 dozen. 9196. Soh Jar, Coplin, of heavy glass, with ground-on cover, for convenient manipulation of sections attached to slides; very economical of reagents. Capacity, ten 3x1 inch slides.................... .40 5% discount in case containing 144. 9198. Staining Jar, so-called “Naples Jar’ with loose fitting hemispherical cover; size, 90 x 35 mm...... 35 9199. ditto, without glass cover, but with cork stopper.............0 00000 c eects 30 9200:. Staining Jar; Harvard,-90) by 35 amimiscs nese eat ee ee te wc tek Co eon hohe ma oes ta le Se 25 9202. Staining Dish, Orton, of glazed porcelain with perforated bottom and six triangular compartments, each with individual number, for use in preparation of tissue from the different regions of the brain for embedding and staining. See Samuel T. Orton, M.D., Some Technical Methods for the Routine Examination of the Brain from Cases of Mental Disease, American Journal of Insanity, October, DDT ier ere Spe igh Batre tocags¥ pe peed EAPC, eee a yd op ERS eS et LE tO to Bey nee eevee ea ete aoe ht 3.85 9210. Staining Rack, Gage, of nickel-plated brass, holding six slides or twelve slides when placed back to back. The slides are held apart by a rack at the bottom..................0.0 00 ccc cece ene 2.00 9212. Staining Rack, MacCallum, for immersing micro slides in staining or fixing solutions. The twelve compart- ment size will take 25 slides when placed back to back; and the twenty-five compartment size will take 50 slides when placed back to back. The boxes listed under Nos. 9214 and 9215 are con- venient for holding solutions, but are not necessary if other containers are available. DSI ZO eg 0s cot et Ra oe cae ee east ha ahed PR or Nga foe copa oe th 12 compartments 25 compartments Ha Cliz £5 evens oe laters tha shite Rn h 1SADs A ees nih en ns eo 5.00 6.60 9214. Staining Boxes, Rectangular, of tin, with cover. Suitable for staining and fixing solutions for use in connection with No. 9212 Staining Racks. Size................0..0.00 00055 Small Large RCI oe ok see Ph alec teat as Geen ade Sarre aaa Re Beh Ces sida eth ols eevee G2 -70 -80 9215. ditto, but of monel metal, which is non-corrosive, with tin lid..... Re Oka che ean 1.90 2.20 9216. Staining Rack, MacCallum, of monel metal wire, absolutely non-corrosive. For immersing eight slides at one time in glass tumbler, or other convenient receptacle holding stain or fixing solution.. 4.00 9217. Staining Rack, of brass, nickel plated, for the convenient handling of slides and for immersion in a large (ipa rent totes meet altel Ctnree sic se tata eh eh Caan tckaa cen epee ane AA AC AR erry 1.00 9220. Stencil, Laboratory Drawing, consisting of a flexible transparent plate with various cutouts representing - outlines of chemical apparatus as illustrated. The ruling edges of the obtuse angle serve as con- venient guides in drawing delivery tubes. One edge has a metric scale for dimensions. MEAG Lise e er cree pens eer steht teas ens open net nese te rl ne ROR AN ae etre cadet IS 2 Spee one econ 16 PGR COZ EIN 2 cies otk Soe ages eet Sy Ae Amato ene EES ERG ead ach sey She rise nen k yes 1.75 vessel of staining flui A RR fF HH rR H. T H O M A § GC: © MP UA. ON: ¥ 9230. 2804. 9231. 9232. 9233. 9230 9232 9236 Stirring Apparatus, with electric motor, consisting of a paddle wheel shaft in a vertical tube with a stirrer driven by a belt from a motor. Particularly recommended for use with Calorimeters, Constant Temperature Baths etc. With universal motor for 110-volt d.c. or a.c. circuits, with which must be used a 60-watt lamp in series. The motor can also be operated on a primary or storage battery _ up to 8 volts. With support as shown in illustration.........0....0...00. 2.00. e eee ee 36.75 ditto; but withoutsuppor tis: ju. cab ood cate nnmeth on ed nanan etn aah nea Nake go MERA See 35.00 Support, with adapter, as shown in illustration, for use with No. 2804 Stirring Apparatus......... 1.75 Stirring Apparatus, consisting of three-step pulley, with improved arrangement for holding the glass or wooden stirrer. The three grooves in the pulley are 1}, 24, and 4 inches diameter. Can be conven- ee attached to upright support by means of an ordinary clamp. Without clamp or glass SUIPT ON sina ot acme kash andes ten c BA eaten Sd na be ate dene alnaie Yala na ola teal codeine jaoety ooo nei agaaina ar Mbit Gt 5.00 Pulley, only, without mounting, as supplied with No. 9232 Stirring Apparatus................. 25 9234. Rotating Anode Holder, only, as furnished with No. 4780 Stirring Apparatus. Can be conveniently used with No. 9232 Stirring Apparatus.................. 1.00 9236. Stirring Apparatus, Blair, consisting of rigid metallic sup- port with six pulleys and stirrers, including asbestos board with openings for beakers, six Pyrex Beakers 400 ml, six glass stirring rods, and six pairs of split watch glasses to serve as covers for the beakers. With- OUG IMO OTs cave siecnsate issn hay ahgueesd ee seh Doras aes eaters 31.50 4780. Stirring and Rotating Anode Device, consisting of support with motor mounted on adjustable clamp with belt drive to two-groove aluminum pulley attached to shaft provided with adjustable clamp with j-inch opening for glass stirring rods, etc., when same is used as a stir- ring apparatus. Into this clamp is fitted a rotating anode holder with adjustable chuck for clamping very small wires. In the illustration this anode holder is shown removed from the apparatus. The whole is mounted on a rigid support with base provided with starting switch and rheostat for controlling the speed of the motor from 50 to 1000 r.pm. The binding posts necessary for electrolysis are attached in con- venient position, but the rheostat is for the motor circuit only and not for the electrolytic current, which tl must be supplied separately. This is a robust and satis- a ae a factory ey device, as ue aoe has ee bed TTT Ne ii | ower to drive other apparatus irom the grooved pulley ARSESURUREAGRERRTTR | PoCT cr tiring operations or elctrolyses are boing | eee el conducted. With motor for 110-volt d.c...... 50.00 Bd wr ol, tm = 4781. ditto, but with motor for 110-volt, 60-cycle, a.c. 50.00 r Ae ie) 7 a 4780 4784 4784 As used in direct stirring In use as rotator for anodes in electrolytic analysis 4784 In use with flexible shaft as 4784 anode rotator 9244 4784. Stirring Apparatus, consisting of Cenco Friction Drive Electric Motor with two chucks for direct attach- ment of stirring rods or rotating anodes to motor shaft, and with flexible shaft for use when anode or stirring rod is to be rotated in a position other than immediately underneath the motor, and with glass stirring rod, and tripod support 24 inches high. For 110-volt d.c............. 34.00 4785. ditto; but *for- 11 0-volti 60=eycley cada oon canes eR Era Se Tne re teehee eat 10.00 12.00 9310. Stopcock, Patent Balanced Mercury Seal. Specially designed for use with Mercury Pumps; 4-mm Ge cea ee pee ek pe SIR RDA NOE TOU pen iy ine gee Cae t Boa ree OLE 8.25 Stopcock Grease, “Lubriseal.” A rustproof lubricant, nearly acid and alkali-proof, for use between either metal or ground glass surfaces. Melting point approximately 43° C, or 110° F. Especially recom- mended for glass stopcocks. Per 1 02. tin......-..+---s+ sere ee eeee erect eet eee ect enes 35 561 AS UR: Ty Se 270) 25 H. T JH) -O. M A. Ss Cc O M P A N _ Y | | H20 : i Hi. ii ee 9320 9315. Stopclock, with an indicator hand to’show the point of starting instead of a fly-back zero setting mechanism as on stopwatches. The large dial is graduated into seconds but the hand stops on }-second intervals. The clock is a convenient laboratory timing device, and as the dial is 53 inches in diame- ter readings may be taken at a distance. ...... 0.0.0... ccc ccc cette n eens 14.25 9316. Stopwatch, Jaquet Antimagnetic, in solid nickel case; reading in } seconds. Recommended as very superior to the ordinary race timers ordinarily used in laboratory work................... 10.00 9317. Stopwatch, Jaquet Antimagnetic, in solid nickel case; with double second hands. By the first pressure on the stem both second hands are released; by the second pressure on the side one second hand stops while the other continues until stopped by pressure on the stem; on the fourth pressure on the stem the second hand last stopped returns to zero, and at the fifth pressure on the side the first second hand returns to zero. By other successions of control, various combinations are possible, ps the watch very useful for timing interrupted intervals, double operations, etc............... 3.25 9320. Storage Tanks, of acid-proof stoneware, widely used for distilled water, acids, etc., in the laboratory. With symbol lettered on front, and with ground-in stoneware stopcock. Capacitys gallonsipAseahiennttecc:dectnainiscteecicun ty ame eens 63 13 263 394 Bence tamer yR coat Oi asten acre tg cn Wace cot dard ae ne Mette mil asia eee ca 22.50 38.00 54.40 85.00 9321. Storage Tank, of tin-lined copper, for distilled water. This tank is constructed of 16-oz. cold rolled copper, tin lined throughout, cylindrical in shape, with a cover at top, tin-lined faucet at bottom, and water gauge“at-side.. Capacity, 2o-eallons: coi concen sie ed ce red he sa ach We ee aE ee 38.50 NoteE—Tanks of 50 and 100-gallon capacity are supplied on special order. Price on application. 8295. Streak Plate, unglazed porcelain, as used in arsenic tests and by mineralogists; 100 x 60 mm 48 9324. Sulphur Apparatus, Meyer, for the determination of carbon in iron and steel by the use of barium hydrate, and the determination of sulphur by the aid of bromine; without stopcock. With 10 bulbs. 2.25 9325. Sulphur Apparatus, Meyer, for the determina tion of sulphur in iron and steel by the bromine method; with stopcock: “With LO" bulbsy sce oh cos ex crquv ae eo Seem ony eh Aen Gea aL eet eee 5.00 562 A 9326. 8450. 9327. 9328. 9329. 9330. 9331. 9332. 9333. R T H U_ R H. T H O M AS Cc O M P A N_ Y 9328—Diagram showing construction 9333 of Parr Sulphur Bomb 9331—Diagram showing cross-section of Parr Sulphur 9332 Bomb in position in water bath Sulphur Apparatus, Norris, complete as shown in illustration, for the determination of sulphur in iron and UOC] os yeast hea ere ean aR eek a RT OSA, cae tect eR cece ee eer eee om Sec aa 3.15 Norris Potash Bulbionly, for above .......cs0 can ee tauee nak peak oheas Gad oA Shed G Marae eau -70 Sulphur Apparatus, as used in oil refining, consisting of three glass parts with wooden base........ 3.00 Sulphur Bomb, Parr, flame ignition, for organic and inorganic sulphur and organic halogen determin- ations when made independently of a calorimetric process. Replaces the ordinary Carius method in the determination of chlorine, bromine and iodine. See Journal of Industrial and Engineering Chemistry, March, 1919. Bomb complete with one extra cup and cover, one wrench and one dozen gaskets.................2... Sa A GCN Aspect p Or hanoe MaDh tas meee wR Ret ean aM ele cc Ze eh 25.00 Cover only, for use with Parr Sulphur Bomb...........0.002 6... eee 1.10 Cup only, for use:-with Parr Sulphur Bomb: oo: o0j.0o5 sped vier pede cess oe eee neee nts 6.25 Sulphur Bomb, Parr, Improved Model, with electric ignition and water jacket. Recommended for de- termination of percentage of sulphur in fuel inspection laboratories; total sulphur in rubber analy- sis; the determination of halogens and organic sulphur in organic laboratories; sulphur in either organic or inorganic combinations in food analysis; and also in soil survey work where not only sulphur but the carbon factor is required for the determination of the organic or humic materials in soils. See W. W. Evans, Chemical and Metallurgical Engineering, 24:19 (1921)........ 40.00 ditto, without water jacket................. Ae bey tha ton sen tap eet RED ED «Bits Se gh 31.50 Sulphur Photometer, Parr, for indicating the percentage of sulphur in coal, coke, petroleum, etc., by mak- ing use of a fused mass secured as a by-product in combustions with the Parr Calorimeter. The mass is dissolved in water precipitated with barium chloride and the density of the precipitate estimated by reading the depth of the liquid in the graduated tube at which the light from the flame disappears, which reading shows the percentage Ol SUP NU: yk oo 2s cys see ares cath eemunenoce 40.00 563 Ae Re ET UR H. T H O M A 5 Cc O M P A N _ Y SUPPORTS On these Supports the rod is not only screwed into the threaded opening in the base, but is held rigidly in place by a check nut underneath the base. 9337 9336. Supports, without Fittings, with rectangular base, of japanned cast iron with copper-plated rod. Size PR OI Ae AF GNU esti tn eee egy a Nr RE eect ety a Ped gee AN iy RRO Ln A aE PR cease Soda Small Medium Large Extra Large Size: of base inches. oo nauensa wast tvthonohuthuns da eere acme as 4x6 5x8 53x9 6x11 Height sof rod; inechess. 2: cua nc cineca and ones sun Rae RS 18 20 24 36 Diameter-of rod, inchésice4 yok age ka cee sands Phew a ae is 3 4 4 Eee th oat oe BN oot on en tM sr Nerd aie Da My, La ba e -40 -60 1.00 1.50 15% discount in case containing.......................... 386 36 30 12 9337. Support, without Fittings, with rectangular base of japanned cast iron 5 x 8 inches with rod in center, 20 inches high by 23-inch in diameter..........0..000 000000 cece cree 15% discount in case containing 36. — 9339 9338. Supports without Fittings, with tripod base, of japanned cast iron with copper-plated rod. S17 Ci pose nnteten Gs tirrcres bi eee) Diet Ble crowd a chk NY ond Shen eae a Pc diy Small Medium Large Extra Large Height-onyod, inches: v2:02 3 iad igh aida: ote Rone ea 18 20 24 36 Diameter of rod, inches.................0... 000000000000. & a 2 2 achive Pesexa pou ore neu cipaibtaedoeny 41 BAA ae eat eee ae 40 .60 1.25 2.00 15% discount in case containing.......................0.. 36 36 30 12 9339. Support, without Fittings, with solid glazed porcelain base 6} x 84 inches, with rod of polished brass, PStinchesshighscver eens nyse mets cere eee vena ta ene e ness bccn nape paste eoensar ea 6.00 9340. ditto, but with porcelain base 14 x 53 inches, and polished brass rod in center, 24 inches high.. 7.50 564 A R T H U _ R H. T H O M A 5S GO _M PA N ¥ 9342. Supports with Rings, consisting of Supports No. 9336 with rectangular base, and Nos. 8760 and 8761 Rings. VAS ee area aU Sha 4 : Small Medium Large Extra Large Number of rings............. Aa ates 2 3 4 4 Inside diam. of rings, inches. : . 23 83 22 383.44 23 31 44 52 223 34 44 54 Each, complete............ acer oe -70 1.15 1.85 2.35 15% discount in case containing............ 36 36 30 12 9343. Supports with Rings, consisting of Supports No. 9338 with tripod base, and Nos. 8760 and 8761 Rings. WAC. 92 ous woe 3 ; : Small Medium Large Extra Large Number of rings........... : pe 2 3 4 4 Inside diam. of rings, inches. , 23 33 23 34 42 22 31.41 52 23 31 43 53 Each, complete................. mye: 70 1.15 2.10 2.85 15% discount in case containing............ 36 36 30 12 9346 9344. Support with Rings, consisting of Supports No. 9338 with tripod base, medium size, and one each No. 8764 Rings 21, 31 and 4} inches inside diameter, and three No. 3214 Clamp Holders, large size. Complete, « .. 1c. nce meee ELAR ERS AGRE LAUM SON MAW tue LmnOaE 14 EWE RRR ER SLR LY 1.85 15% discount in case containing 36. 9345. Support, with Rings, consisting of No. 9339 with rectangular porcelain base with three brass rings with porcelain inset, and screw clamp.......... re ere 7.50 9346. ditto, but with wooden inset in place Of porcelain 5519 wea eie ir a Net oy sous Sa vas 7.50 9848. Support, Universal, for holding rods vertically or horizontally, with rod 18 inches long............. 55 10% discount in lots of 25. 15% discount in lots of 100. 565 R. THe UR En. T H OO M A S Cc O M P A N_ Y 9350. 9351. 9352. 9353. 9354. 9355. 9356. 9357. 9360. 9361. 9362. 9353 9355 9350 9354 Support, consisting of triangular Bakelite finish base, nickel-plated 6-mm rod, nickel-plated clamp No. 3288 for holding conductivity cell, nickel-plated clamp No. 3293 with holder No. 9354 and rod No. 3291 for attachment to side of constant temperature bath, and mercury contact No. 9354 at top of rod. This support is also intended for use with conductivity cells when immersed in a constant temperature bath. Complete as shown in illustration......................0.2..00005. 9.70 Support, consisting of triangular base with nickel-plated 6-mm rod, mercury contact No. 9354 and clamp INO e232 Silko cae ices MEP RAL Siacemtc nh Cererng mice see dota 2. Melanie aa tak psn eo Oen ener ng ieee ice His mani te aceeaet ree eyOS 6.70 Support, consisting of triangular base and mercury contact, but with No. 3288 nickel-plated clamp, 6 mm, for:conductivity: cell: is cun vers. i ection aang to ye AK nA ree ul ool odoin a, Ae TES Gans ac 5.30 Support, consisting of triangular base, Bakelite finish, with nickel-plated rod 6 mm diameter, as listed UINCeT JNO: S50 iy soe sure ean bavema tek A oN AeA U Ie else, RagteR Slt Sats hye means, & tune ena At weno rags 2.20 Mercury Contact, of hard rubber, for use on a 6-mm diameter support rod....................-. 2.20 Support, consisting of iron base, heavily japanned, with removable, nickel-plated rod 6 mm diameter; a stable and convenient support for conductivity cells, electrode vessels, etc. Recommended for use with Clamps such as No. 3286 to No. 3293, inclusive 9356 9357 Support, consisting of rectangular base with nickel-plated 8-mm rod, nickel-plated clamp No. 3218 and wooden clamp No. 3286 at top for connecting wires. This support was designed particularly for use with Conductivity Cells Nos. 3978, 3980 and 3982 but will be found convenient for use with other cells not intended for immersion in a constant temperature bath.................. 2.85 Support, only, consisting of rectangular base, with nickel-plated rod 7 inches high and 8mm diameter 1.50 Support Tables, with iron tripod, brass rod and wooden top, adjustable as to height. Height: éxténdedsmmy..gs.i40.94 2 aciess Sead Baars GG Se NR eS ee aes 300 400 Diameter Of GOP) MM — seis «aces eens een it Mek, nese a emer nee a vey dd Sas BOGUS 90 125 Fei ght: Closed ssmnin visssea esac ws aie sh ateh ee pease eh A LAI emo Ae tee Ls GEGEN RETR 190 240 PO i Rea ig ee ny a eed oe pened eee dogg e lueval ne aca Oe war ne D rlee e are meed 4.50 5.00 Support Tables, of polished wood, adjustable as to height. Heightvextendéd sy MIM. sc.g sr ook hea wae be ane era PEN eee Pee el ate 200 400 Diameter Ol GOp MMs crk sec uees nsyrarccs anew eo ouees Mtid dace see woe eden 70 125 Height:closedis amir s eorse0 aoe 2 entire a tie in eidd termes sett AI ORM ela Nah leans 120 240 BI acess sce ash eS ae eae sin ee ce Pa he tet traas Ze Sd Gola code eco ek FA Cages 28 1.80 2.30 Support Table, of cast iron, with clamp for fastening to upright of apparatus support, 5 inches di- ATV CL OT avai ee da eh cise een oe Sea hk SBA A aura hai ag fact Ue ve Seep eee aie aie eco eorenaal ke Bee a seas 35 A. R. TF -H. U> R H. T H O M AS GC. -O- M PAN: Y g\— — ‘\ 8024 8030 8024. Support, for holding recording apparatus, of iron, with base 130 x 130 x 20 ith 10- ickel- rod 24 inches high, right angle clamp and extension rod.......... pet ; et oreo 025. Right Angle Clamp only, as used with No. 8024 Support.......000000000 eee 1.00 8026. Extension Rod only, as used with No. 8024 Support......................esseeeessceeeeeeeee 470 8030. Support, Jackson, with heavy cast-iron L-shaped base. This form of base permits the use of several stands in close juxtaposition, so that supports can be placed within one or two inches of each other to carry recording devices which must be adjusted within a very small space. The rod is 7/16- inch diameter by 24 inches high. See Jackson’s “‘ Experimental Pharmacology,” p. 497..... 1.50 8034. Support, Jaquet Universal. A most convenient support for graphic experiments; with large heavy base The various adjustment screws and micrometer fine adjustment permit the most exact adjustment in relation to the recording drum. Total height, 550mm.......................... 72.00 8033 4772 4774 A most convenient and suitable apparatus support for physiological work. ble arm and upright permits convenient adjustment of the writing device ding arm. The upright rod carrying the apparatus is fitted with fine 8033. Support, Jaquet Adjustable. The arrangement of mova in contact with the recor adjustment for precise regulation......-..-.---cseretrse cee e teeter ena 31.00 4772. Support, Electrolytic, with japanned iron base, glass upright with ring with three platinum lugs and one clamp, and binding post attached to both ring and clamp.............-- sees eee eee eee 3.70 4773. ditto, but with two clamps with binding POSES: 2: is eRe tniemderseoe gwen adap gat reise *.. 5.00 lamp and separate glass upright carrying ring... 3.70 4774. Support, Electrolytic, with glass upright carrying ¢ 567 A R T H U_ R EL, T H O M AS C07 M.-P’ oA GN: UY: 9366 9367 9366. {Surface Tension Apparatus, du Noiiy, especially designed for the reliable determination of the surface tension of colloidal substances such as serum, blood, ete. A rapid series of measurements can be made in such a short time that the substance tested has no time to be modified by its contact with air. Only a very small quantity of liquid, 1 ml or less, is necessary. The use of such small quan- tities results in the temperature of the liquid being about that of the room without other tem- perature control. The accuracy of the apparatus is far beyond the needs of ordinary laboratory work, as is evident from the curves obtained for water. Measurements can be made in from 15 to 20 seconds. Designed by Dr. P. L. du Noiy, of Paris, France, while on special service in the U. S. with the Carrel Mission at the Rockefeller Institute for Medical Research. See The Journal of General Physiology, May 20, 1919, Vol.I, No. 5, pp. 521-524 0... eee 60.00 9367. Surface Tension Meter, Gardner-Holdt. A surface tension apparatus for the measurement of the relative values for the interfacial tension between liquids by air bubble method. As designed and used for varnishes and paint liquids in the Henry A. Gardner Laboratory of The Institute of Industrial Re- search; see Circular No. 124, “Surface Tension and Interfacial Tension of Varnishes and Paint Liquids’, by Henry A. Gardner and P. Charles Holdt, published by the Educational Bureau of the Paint Manufacturers’ Association of the U. S 9373 9374 9378 9379 9370. Swimming Cups, Porcelain, with perforations, for washing specimens. With cork stopper which floats the cup in the washing fluid. Height,mm..................0.0.0.0...0..0 00005 35 55 PD iaIMOLER IMIG ee as acces weg ee See cr ae tea ae yes AE cere Pea ph Pe ae a 26 36 TBD yg i ae tral et Sewn laete aa scponianalsy slid tenalia Coscseln wae Wiel teeter ce a vals weenie mens eo amet es 44 -66 9372. Switch, Knife, Double Pole, Double Throw, 125 volts, 15 amperes, porcelain base, without fuse socket 1.00 9373. ditto; but: single: pole; single: throw: 2-95 34 evades Maa eeee 22.50 Support, only, for reading telescope, as supplied with outfit No. 9434. This support consists of a heavy tripod with steel leveling screws and fitted with convenient vertical adjustments which make it very suitable for reading thermometers or following any vertical motion. A rack and pinion adjustment of 150 mm range is provided in the top slide and a hand adjustment of 100 mm range is given in the lower support tube, which also permits rotation. Suitable also for use with No. 4806 Reading microscope s...0 0 s4 ose rg wate rte Fhe thee eatin e ee 30.00 Test Glasses, for collecting sediment; conical form, with foot and spout. (CARO Meso cv gc rennet ee eee eee Oe RR eA E Stair 50 100 200 ache ee ed eee ae A ase eee ea ce 25 .30 .45 20% discount in case containing. ......-. 02-620 e reer erent teens 420 288 144 seededa Nl oe hen cae sok cs ea suanecoestcunape Aten ty weet 85 ditto, but graduated. Capacity, 200 ml TO sneer e Test Glass, cylindrical form, with conical bottom, 83 Ms ey pe pe hath ln eee et RV Ur wheres bg Se Nee noe Saeed EA EMEA cae D IN Man 20% discount in case containing 96. Test Glass, tall conical form with blunt bottom, 200 mm high, with spout. Capacity, 200 ml....... 50 573 A R T H U_ R H. TA 30M A. 5S CO Me PA IN OY TEST TUBES All dimensions given for test tubes are outside measurements. Please do not specify inside dimensions for test tubes. Our test tubes, except Pyrex, which are packed at the factory, are all selected, gauged and packed in our establishment, and we endeavor to keep within the following tolerances for outside diameters: Outside Accurate Outside Accurate Diameter to Diameter to mm...........—1 mm 18 mm...........4? mm 11 mm. ....-1 mm 20CMIMN kee Ae lee +1mm 12 mm... —1 mm 22 mm. ... £1 mm 13 mm. —1 mm 25 mm...........4l1 mm 15 mm. ... +2 mm 27 mm...........£13 mm 16. MMe neues eas +? mm Asa result of an exhaustive series of experiments over a period of several months, we now confine our stock of heavy wall Test Tubes for bacteriological work (Culture Tubes) to those made of a selected lime glass tubing, 7.e., that used for the manufacture of the best chemical apparatus before the lamp, and to those made of Pyrex Glass 702-EJ, the glass used for Pyrex flasks and beakers. The lime glass we have selected for our Culture Tubes has proved entirely free from any corrosion or etch- ing as the result of repeated autoclaving. Bacteriologists using these tubes in large quantities with this difficulty in mind, confirm these experiments in this regard. Where a very slight difference between the initial and final reaction of the media is of supreme importance, or where the technique employed involves repeated sterilization of the Culture Tubes in the hot air sterilizer, we recommend the use of Pyrex Culture Tubes No. 9450. WIG? X 0S? geuyieeeeeee| | | N | | IB 7 Hi | | | Tut 9444 (14 Actual size) 9444. Test Tubes, With Lip, of selected lime glass tubing, thin wall, for chemical work. Packed in cartons of 100 each. j Length, mm.:...... Ret ee ates Mette eos 15 100 120 120 120 150 150 Outside diameter,mm........ ee 11 12 13 15 18 16 18 Per carton of 100.................. 1.54 1.60 1.75 2.00 2.00 2.00 2.30 20% discount in cases containing...... 1800 1800 1200 1200 1200 1200 1200 Tsength, MM... ce echece ya cena eee ete: 150 150 175 200 200 250° Outside diameter,mm............. eres 20 25 20 20 25 25 Per carton:of 100...-........... iitpenn 2s08 3.50 3.70 4.00 4.60 6.00 20% discount in cases containing.............. 1200 800 800 800 800 800 Prompt, accurate and economical service is much facilitated by the use of the specified package quantities—or even multiples thereof—in the preparation of order lists for test tubes. The co-opera- tion of consumers in this detail is of supreme importance in order that the economies planned may be effective. Ay URS “EU GR H. T H O M a) wre) % OS) a wu gx SZP = =) fieeze , 1% |i | | 0 | | o| 3} x os a ae 3 5 ut G1 x 001 en 9446—(14 Actual size) 9446. Test Tubes, Without Lip, heavy wall, for culture and serological work. These tubes are guaranteed against corrosion after repeated sterilization in the autoclave at 120° C. They are carefully formed at the ends and are packed in cartons of 100 each. The smaller sizes of this series are those mostly used for serological work, and the size 75 x 10 mm is that used inside of the 150 x 16 mm and 180 x 22 mm tubesin Dunham’s fermentation methods. Size 100 x 13 mm is that mostly used for Wassermann reactions. Size 210 x 27 mm is the Buchner Tube as used in the cultivation of anaerobes. Weng thy mma teed ee Rede ne nies 75 15 85 100 100 100 120 120 = 120 Outside diameter, mm. . Epareee re a WO eg 15 10 13 16 13 16 18 Per carton of 100..... soo.e...... 1.80 1.90 1.90 1.90 2.06 2.28 2.12 2.28 2.52 20° discount in cases containing...... 1800 1800 1800 1800 1800 1800 1200 1200 1200 Ten Sth omits 8 wrt aay eae ae . 125 150 150 150 150 180 200 200 = 210 Outside diameter,mm............. 13 13 16 18 20 22 15 25 oT Per carton of 100.................. 2.10 2.40 2.50 2.70 2.70 5.16 4.00 5.60 6.10 20% discount in cases containing...... 1200 1200 1200 1200 1200 1200 800 800 800 ey Z| soe Se 7 woz x SZt xB UAd = win GZ x 002 " | < D my xT _xXBuAG a ° x b = z wm O1x OSI a < 2| in j Ih } 9448— (14 Actual size) 9450—(4 Actual size) 9448. Test Tubes, Pyrex, With Lip, medium wall, for chemical work; recommended for all purposes demand- ing a maximum heat resistance and mechanical strength as well as minimum solubility. Because of these physical properties these tubes are made heavier than is usually possible for direct heating in the flame. While the initial cost is high, the unequaled mechanical strength of Pyrex glass makes them economical in the long run for certain purposes. They are not intended for use as, nor are they as heavy as Ignition Tubes (see No. 9454). Size 200 x 25 mm is that used in Folin’s method for the determination of total nitrogen, urea and ammonia in urine. Reve Ee mnie s ek ee es i eA Ne eel cies 100 120 150 150 175 200 250 Outside diameter, mm... ena acs seers 13 15 16 18 20 25 25 Per 1 0s ceo iike tices Ae tok SEC ae see -70 -90 1.10 1.20 1.30 2.50 3.60 10% discount in cartons containing.............. .. 200 100 150 150 100 50 100 ithout Lip, medium wall, for culture and serological work; recommended for use aioe Ors ean diferones between the initial and final reaction of the media is of supreme importance, or where the technique employed involves repeated sterilization of the Culture Tubes in the hot air sterilizer. Although the original cost seems high in comparison with other culture tubes, bacteriologists report an ultimate economy in the use of Pyrex culture tubes because of the remarkably small breakage due to the great mechanical strength of the glass. estate el ek ha 100 150 150 200 Len thy WAM secrecy os oes Tee wi RENE PETA Bees Outside diameter, mm. . NN etek On CAE ASMA? Reis kG na tere tere tek : 13 16 18 25 Der 10 renee eRe a gn ore ep nem .... .80 1.00 1.10 2.40 10% discount in cartons containing.......-...---. 06... eee eee 200 150 150 50 & OR TE SH UU oR fh a GER Oe Mn sAs 3S GO" (MP > Z < "MTT | r ia QO > qr, gid a =O! ANT CCl a Mas wu $9 x OOS wuwog x OO lo | lo w \ lo ji o ° ; (83 | oy] og | xn wa ow? vm] vd om Hi gx! aM) 5x I z | 3 3 ‘ oS 6 ix a a 9452. Test Tubes, Extra Large, of Pyrex Glass, medium wall, without lip. These have been found useful for a variety of work, the larger sizes being convenient for the sterilization and storage of sterile pipettes 30 40 9452—} actual size) 9454—} actual size) in bacteriological work. cee mm..... fate Seah ... 300 300 0 0 500 Outside diameter, mm................... piers: oe 32 38 50 65 Be ate Aa ee wep eat wie pace a Ac eed eee ae Ree Se .38 50 68 1.19 1.67 9454. Test Tubes, of Pyrex Glass Sentient Tubes) with very heavy wall and flaring lip. Teneth; MMs, sccutswccie eave ogsas ort Aye aap a oh Se Sara 100 125 150 200 250 Outside diameter,mm................-.--5 ee : : 16 16 18 25 25 Per Os grace ahs Aven, oxen Pehcaltre aiken : _... 1.30 1.30 2.20 3.40 4.50 10% discount in carton containing. . ‘ Sates LOO! FLOORS 100 50 100 9460. Test Tubes, with side neck and lip. Length, TPN. Gene wis ane SA eee SE 120 150 180 200 PLavG He occu ees ene ctel & wate NUN aie bare sa eres eRe eres rhe 10 12 13 14 10% discount in carton containing 12. 9461. Test Tubes, with lip and foot. Height,mm....... _ 100 125 150 175 200 250 MBS AC a i) Sees see A tee name ene acheter ate Oe 10 12 15 -20 -20 .30 10% discount in carton containing 12. 9462. Test Tubes, Graduated, with lip but without foot. Capacity, ml i 15 20 25 30 Graduation interval, ml.............0. 020562 e eee ees + + 3 3 Bie Wet) eee arte oesaires are nie ener ee are Repeats . 25 35 .40 45 50 10% discount in carton containing 12. 9463. Test Tubes, Opaque Silica, Glazed. Contrary to regular practice on sie test tubes, the dimensions given areinside.. ‘Sizeanches. . .<.iscnves PPeY te ey deere ek ate ee .. 4x34 5x2 6x3 Bae hie. ecient aes Oe arse eR PRES, eA ae eek eee en .. 1.00 1.45 2.10 9464. Test Tubes, Transparent Silica, with heavy wall and lip. Dimensions given are inside. GiZOsANCNCSag is os ue eh ie eas eshe nla tise een pe aNd Gey em etea Caet er rye 4x} 5x? 6 x NaC cs Ce csc rn to reece ctececes ar eatege oel &Oe TG GEA ROD an Ole eh As s.y « 8-00 4.75 6.40 A OE Re A Oe Mn cA. CS Cc O M P A N.Y | ie nl | Leo ml 50 +15 35 9470. 9471. 9474. 9475. 9476. 9477. 9478. r—10} |L_.25 4 [12.9 i | i , i: Le ! f LP? To I LY Ly - Hohe pert cil 3560 3556 3554 3550 3552 “9470 9471 Blood Sugar Tube, Lewis-Benedict, graduated at 12.5 and 25 ml, for use in sugar determination; of resistance glass with heavy wall and slight lip; dimensions 160x25mm.................. Blood Sugar Tube, Gradwohl-Blaivas, graduated at 1, 4, 10, 15 and 20 ml, for determination of sugar in blood; of resistance glass with heavy wall but without lip. Dimensions 150x18mm...... 50 Blood Sugar Tube, Myers-Bailey, similar to No. 3560 but with dimensions 200 x 13 mm and graduated at 3, 4, 10, 15 and 20 ml. See Myers and Bailey, Journal of Biological Chemistry, 24: 147 (February), 1916, and Victor C. Myers, Journal of Laboratory and Clinical Medicine, V: 559 (June), 1920 .50 Blood Sugar Tube, Folin, improved, in accordance with author’s latest specifications, graduated to 25 ml and with the bulb of such capacity that the surface of the alkaline mixture of sugar in copper falls on the lower half of the parallel constriction; also used for the determination of creatine plus creatinine. See O. Folin and H. Wu, Journal of Biological Chemistry 41: 372 (March), 1920 .60 Blood Sugar Tube, Folin, identical with No. 3554, but without graduation mark at 25 ml, i.e. for calibra- tlonaNsChe a DOPAtOny sce hv ce ark on seh pean wat Cone es Meche koran marcha pnuat uaial’ wc lxGes ee Rey oR a -40 Digestion Tube, Folin, for use in the micro-Kjeldahl digestion of blood filtrates in small quantities in the determination of non-protein nitrogen in the blood; also used for the determination of urea in the blood by means of urease and aeration and by the method of autoclave decomposition. Of heavy Pyrex glass with graduations at 35 and 50 ml. The graduation provides for the convenient nes- slerization in the digestion tube. See O. Folin and H. Wu, Journal of Biological Chemistry, 38: BL CIVIC ZL T Ge crest se sy oe ides Canvas Pohash ea he gh se iam Piet aaron IM seed geht meek SAI ho Bi a enh Re .70 Receiving Tube, Folin, for the determination of urea and urease decomposition and distillation by the micro-Kjeldahl method. Also for use as an Amino Acid Tube according to Folin’s new method. Medium heavy wall, without lip, with graduations at 12.5 and 25 ml. See O. Folin and H. Wu, Journal of Biological Chemistry, 38: 87 (May), 1919......... CPE eaea ess Rien ben eae .30 Test Tube Filling Attachments, for measuring out exact quantities of fluid. Consists of a separatory funnel with two-way stopcock and graduated side tube. Without support and ring. Gapacitys Mle .cnccy oi canes Me atorne ane cae nos Cae Si uss dn mesg souks See A Bite Saw ee eI TS 500 1006 Paha hectare tne rhe ae a per PMR eeOBE AA ule ech teas Seek ey sec uenaes ... 4,85 6.45 Test Tube Filling Attachment, for use in filling culture tubes, flasks, etc. This device prevents contact of fluid with the surface of the vessel being filled, so that the latter remains clean for the insertion fines K ve Xy Xi xh) y sket, cylindrical, 6 inches high by 10 inches diameter. Of dipped galvanized wire. Con- ae silage ae in autoclaving media. Two of these baskets can be used in No. 1657 American i BS EOTUT OMe s cast rus any Senna cena AREA I nse een Eat Susie lieeaanershee a ee ict 1.70 Standard Vertical Sterilizer............-... 550-520 Sint ser awyrum eae natn a3 ditto, but with four vertical compartments to keep test tubes in upright position.. . .... $3.50 Test Tube Basket, cylindrical, of dipped galvanized wire, for use in incubators and sterilizers; 6 inches high by 5 inches eee Se ne Royce Soa ee et poe dent eras Oe rot cee 1.00 10% discount in case containing 00. ; ; ditto, but rectangular; 6 inches high by 4 inches wide by 5 inches long. . 5 ; ora _ 1.00 10% discount in case containing 50. Test Tube Basket, rectangular, of dipped galvanized wire, 44 inches high by 4} inches wide by 5} ne TOME se eden s gee mts OS Pee et An tea neat noes PES BLE ieee Rete : Gy wea ay 9482 9483 9484 9482. Test Tube Support, rectangular, of dipped galvanized wire, with double shelf, for forty test tubes up to , 22-mm diameter. . pO ede eR ino pei toa hppa ae pA dls A yeti eS cha eiataa tense Cay Sate aS .90 9483. Test Tube Support, rectangular, of dipped galvanized wire, with double shelf, for ninety test tubes of not oe 13-mm outside diameter, as used in serological work. Entire rack may be immersed in water BATA ea ends Le rece HES IRDA ER Dc ee a Rie ear Me RAEN Sahl eth ty een ae ih a oh mone a tiee, Le OO) 9484. Test Tube Support, circular, of dipped galvanized wire, with double shelf. Dimensions over all 9 inches by 43 inches high. Holds forty test tubes 20-mm diameter. Will fit No. 9864 Water Bath, LOzinehs diameters sos tos ke eng ale ma Ye tetles mens Zc aledi cui aki smn ln ae ane See aed 1.10 9485 9488 9489 9490 9485. Test Tube Support, square, of dipped galvanized wire, with double shelf. Dimensions 73 inches by 33 inches high. Holds forty-eight test tubes 20-mm diameter......--....+-- +--+ sess eres 1.20 9488. Test Tube Support, of copper, for use in water baths, incubators, sterilizers, etc. Holes are 23-mm diameter. Diameter, inches............0..0 0000 cette ttt 5 8 Number of holes....... Re CRO tras ues eR Carte aA ena aan ROG a 14 19 36 Bia lagen ie saeco ees ecient ee tee eRe Seay dian Mads Tato SieseeRem eee aaah 2.00 3.00 3.75 9489. Test Tube Support, of copper, for use in Inactivating Baths Nos. 1720 and 9872, 52 inches diameter, with nineteen holes ;%-inch diameter.............-05 50000 cc ee ene 5.00 9490. Test Tube Supports, of copper, with bottom shelf having flange to receive contents of tube in case of breakage; for use in incubators, sterilizers, etc. With twelve 23-inch holes. Sizes an CHES voctva ccesussae: enienre hac cetigce oe oaueen Gi hm Sabi ayaa ed DARING re ee 8x4x2h 3x4x 4} Each...... fed aa ee hat te dek gh “cg eee Pa -a gO AERA aA STR ADS PE EERE 1.75 1.85 9492 9494 9495 9492. Test Tube Support, or Wassermann Rack, latest U. S. Army Medical Department model, of 20-02. copper with weighted bottom, 101 inches long by 2 inches wide by 43 inches high. With twenty ;-inch holes, each pair numbered consecutively from 1 to 10. This rack is much more expensive in construction than the lighter weight rack No. 9493, and is recommended because of its stability. Foruse with test: tubes: 100: by 13 Mim 2 acs an ale ea ose een aus Me ee eS 3.25 9493. Test Tube Support, or Wassermann Rack, of 16-oz. copper, otherwise similar in specifications and shape to No. 9492 rack; but without weighted bottom. This is the rack supplied with Wassermann outhts: Noss 1 (30) 17 S36cand' (50x uw ewes Ged metiealuend «SUA a mata mene b se ane 2.60 9494. Test Tube Support, or Wassermann Rack, of copper, 8} inches long, 1% inches wide and 4% inches high over all, as used in No. 1756 Serological Water Bath. Each rack has twenty openings in two parallel rows of ten each, to take tubes up to 13-mm diameter. The front row is numbered from 1 to 10, and the racks are numbered serially from 1 to8... 0.2.2... ee 2.50 9495. Test Tube Support, or Wassermann Rack, of nickel-plated brass with adjustable supports for suspension in water bath, and furnished with three shelves as illustrated. Capacity forty-eight tubes 75 x 11 mm. Dimensions of rack 9 by 4 by 2} inches high. Height over all 8 inches. For use with No. 1760 Water Bath, with which it is regularly furnished............... 0.00... c eee eee eee 5.50 578 A RT ae UR H. T H O M A _ §S CeO EMiy PAG INT oY | De eooe Se eo Da Oo BO OS DS DD ma nt TaN | eee 9503 5076. 5077. 9504 9505 9506 9507 Test Tube Support, nickel plated on iron base, 6 inches high by 11 inches long, with holes ;-inch diameter fOr GET LeStsbUOS es utes nation elvan toMaya natant iN Wiehe seeh oui Same eran Ot Ae sone oe, atewroe Ci cuanea ast vated 1.85 Test Tube Support, or Wassermann Rack, made of iron, white enameled, with slanting bottom shelf for convenient color comparison. The holes are ;%-inch diameter. Naim ber Of WOLESe Scie ase he a Set bow Ps eat A wor inet Nn ee eat al sterbegaes woes actly monies tg 12 16 ME Nec esc rs vals ae ed Se daatp & Sma eae aen Sas acaainel ae Gea Pee een tener a eae 1.65 2.10 Test Tube Support, Universal, of enameled cast iron, for test tubes, fermentation tubes, albuminometers, ureometers, etc., not over 5 inches long and #-inch diameter. Entire rack may be put in sterilizer, incubator, or water bath. Total height 53 inches.................0..0 00.2002 eee eee 2.50 ditto, but of aluminum with sand-blast finish.........0. 00000000 4.50 TEST TUBE SUPPORTS, as sold by us and listed below are put together with brass pins, and do not come apart. All holes are full 22 mm diameter, except where otherwise specified. 9500. 9501. 9502. 9503. 9504. 9505. 9506. 9507. Test Tube Supports, of beechwood, oil finish, single deck, single row. Number of holes.. 6 12 BE a Cine tte er a eee es aM See ean See aerate eco ra rap eaae Pci Samet ak Peon a 50 -65 10% discount in lots of 25. 15% discount in lots of 100. ditto, but with holes 30 mm in diameter. Numberof Holes: 2). .04 cota Sexe hanas Bea pee Sane Mia Run ewan ROR ee 6 12 Bac hitccnne le bp a ee thoes ak aa se etn eet cae Slate Quin Seahaee, Cas oem entre Bias clare ute erences oe -60 75 10% discount in lots of 25. 15% discount in lots of 100. Test Tube Supports, of beechwood, oil finish, with pins in rear, single row, single deck. Number. Of HOLES: -ccrsae auth ces rnb hc ees Ay ees One ares IGM area AR Med 6 12 EAGT ate hcg eater tae Bee a tee en yates Sone eat ea aden Bcc yagh Oa ceo tan can cto on eigt ttre -60 .80 10% discount in lots of 25. 15% discount in lots of 100. Test Tube Supports, of beechwood, oil finish, single deck, double row. Naam ber Of Noles ne. ac: sue coetetuesanteantay inlo gaged ae eule nek oma Gad yo herrea gts 12 24 By CEA nee tea aera Da ey ee et te OOS epee Cm Ue ee ener Pie te Ma aan So ay er -65 75 10% discount in lots of 25. 15% discount in lots of 100. Test Tube Supports, of beechwood, oil finish, single deck, double row, with pins in rear. Nithber of holeSics-s ces Guaicaer uaa pan titer andes ae orks CMa ariota yes sua 12 24 Pe a oc tee ee ahs eA a a mene Rey os ene 80 90 10% discount in lots of 25. 15% discount in lots of 100. Test Tube Support, of beechwood, oil finish, single deck, double row, with twelve holes 30 mm Giameters ic ick akemi eee pee eprieat pple Sa tUs A ee acer Se Mr sibee uaa, arriba hh sse a aetna ATG Za .80 10% discount in lots of 25. 15% discount in lots of 100. : Test Tube Supports, of beechwood, oil finish, double deck. : Nurmber of holes?...4.cs ave sea de Senay aes eA ele can talekdbors Gia anaes Setar as Sane ERS 12 24 MECH oie ase ee hie ioe tes ae rte Se ae a at aaa ace ca erereag etsSn nae -70 -80 10% discount in lots of 25. 15% discount in lots of 100. Test Tube Support, of beechwood, oil finish, double deck with pins in rear. With 12 holes......... .80 10% discount in lots of 25. 15% discount in lots of 100. 579 9508. 9509. 9512. 9513. 9516. 8517. 9518. 9520. Re se HE Ly H Te A Or Me cAL cS Cc O M P A N Y 9516 9518 9520 Test Tube Support, of beechwood, oil finish, double deck with two rows on lower deck and one on upper deck. With 24 holes... . 10% discount in lots of 25. 15% discount in lots of 100. Test Tube Support, of beechwood, oil finish, double deck with two rows on lower deck and one on upper deck. With row of pins in rear and 24 holes............... : e 10% discount in lots of 25. 15% discount in lots of 100. Test Tube Support, consisting of wooden block with 12 drying pins........................ : .40 Test Tube Support, for hanging on wall, consisting of board with 18 large and 72 small pins...... 4.00 Test Tube Support, of stamped steel, black enameled, with 14 holes of 1-inch diameter,and with 7pins —_.65 Test Tube Support, for Wassermann and other serological work. Of polished copper, 9} inches long. Holds forty test tubes 75 x ll mm........................ Peta oree orn tai ed ay E eee ae 2.40 Test Tube Support, for Wassermann and other serological work. Of polished copper with opal glass plate at bottom for convenient observation of haemolysis; 13 inches long. Holds twenty-four Gest t ules 7 ore AM sian es Me Rh lel an al Remewras lade RUIN ieale nee Rudlelan csr atts fax Alas 4 cheb vie) tee nee, 22280 Test Tube Supports, Serological, Deibert, of heavy sheet copper. Test tubes are held against the upright support by tworubber bands, as shown in illustration. The racks takes ten serological tubes 100 x 12 mm, or six culture tubes 150 x 16 mm. The open space above the base permits unobstructed observation of the lower ends of the tubes by transmitted light, while the entire contents of each tube is exposed to view from one side. The taper shape of the base permits compact storage of the racks when filled with tubes by telescoping one base over another, in which procedure it has been found convenient to put a larger rubber band around groups of racks up to twenty for handling as one unit. In order to detect possible displacement of any given tube in a rack, the author rec- ommends the use of a diagonal grease-pencil mark drawn from the base of the first tube to the top of the last to indicate proper relative position in the rack. The rack as ordinarily made is 5 inches long by 34 inches high. See Olin Deibert, “A Test Tube Rack for Serological Work,” Journal of Immunology, July, 1921. Each, without rubber bands eine arma Ribas 1.60 10% discount in lots of 12. 20° discount in lots of 144. All systematic plans of catalogue arrangement lead, if consistently carried out, to inconve- nient location of certain items. Our general arrangement is alphabetical, but in a number of instances the ‘‘group’’ system has been followed as a more convenient arrangement. Our index is very complete in that articles are indexed under all the principal words of the | name, thus ‘‘Crowell Type OD Rotary Air Pump for Vacuum and Pressure’”’ is indexed in six places, | i. e. under Crowell, Rotary Air Pump, Air Pump, Pump, Vacuum Pump and Pressure Pump. As the authors’ names are printed in heavy face type and in alphabetical sequence, a separate author’s index is omitted. 580 A URe i she UP oR H. T H O M A 5S C O M P A N _ Y THERMOMETERS Fahrenheit? = —entigrade” x § + 32. Centigrade® = Pobrenket = 32) xX 5 Ready Reference Comparison of Centigrade and Fahrenheit Thermometer Scales Cent.° | Fahr.° Cent.° Fahr.° Cent.° Fahr.° Cent.° Fahr.* Cent.° Fahr.° Cent.° Fahr.° —40 —40 7 44.6 38 100.4 69 156.2 99 210.2 245 473 —35 —31 8 46.4 39 102.2 70 158.0 100 212.0 250 482 —30 —22 9 48.2 40 104.0 71 159.8 105 221.0 255 491 —25 —13 10 50.0 41 105.8 12 161.6 110 230.0 260 500 —20 — 4.0 11 51.8 42 107.6 73 163.4 115 239.0 265 509 —-19 — 2.2 12 53.6 43 109.4 74 165.2 120 248.0 270 518 —18 — 0.4 13 55.4 44 111.2 75 167.0 125 257.0 275 527 -17 1.4 14 57.2 45 113.0 76 168.8 130 266.0 280 536 —16 3.2 15 59.0 46 114.8 T7 170.6 135 275.0 285 545 —15 5.0 16 60.8 47 116.6 78 172.4 140 284.0 290 554 —14 6.8 17 62.6 48 118.4 719 174.2 145 293.0 295 563 —-13 8.6 18 64.4 49 120.2 80 . 176.0 150 302.0 300 572 —12 10.4 19 66.2 50 122.0 81 177.8 155 311.0 310 590 -11 12.2 20 68.0 51 123.8 82 179.6 160 320 820 608 —10 14.0 21 69.8 52 125.6 83 181.4 165 329 330 626 —9 15.8 22 71.6 53 127.4 84 183.2 170 338 340 644 — 8 17.6 23 73.4 54 129.2 85 185.0 175 347 350 662 — 7 19.4 24 75.2 55 131.0 86 186.8 180 356 360 680 — 6 21.2 25 77.0 56 132.8 87 188.6 185 365 370 698 — 5 23.0 26 78.8 57 134.6 88 190.4 190 374 380 716 — 4 24.8 27 80.6 58 136.4 89 192.2 195 383 390 734 — 3 26.6 28 82.4 59 138.2 90 194.0 200 392 400 752 — 2 28.4 29 84.2 60 140.0 91 195.8 205 401 420 788 —1 30.2 30 86.0 61 141.8 92 197.6 210 410 440 824 0 32.0 31 87.8 62 143.6 93 199.4 215 419 460 860 1 33.8 32 89.6 63 145.4 94 201.2 220 428 480 896 2 35.6 33 91.4 64 147.2 95 203.0 225 437 500 932 3 37.4 34 93.2 65 149.0 96 204.8 230 446 520 968 4 39.2 35 95.0 66 150.8 97 206.6 235 455 540 1004 5 41.0 36 96.8 67 152.6 98 208.4 240 464 560 1040 6 42.8 37 98.6 68 154.4 5 REMOVAL OF MERCURY FROM THE UPPER RESERVOIR’ AND OF GAS BUBBLES FROM THE MERCURY In the handling of thermometers it is often found necessary to manipulate the mercury within the capillary, in order to reunite with the main column a part of the mercury which has become separated, to remove gas bubbles from the mercury in the bulb or stem, or to separate a mercury thread for use in calibrating. There are four operations usually resorted to in manipulating the mercury, viz., (a) warming, (b) cooling, (c) tapping on the end, and (d) tapping on the side of the thermometer. Warming the bulb of a thermometer may be done in water or oil or in air high above a gas or alcohol flame, but great care must be taken, especially with high temperature thermometers, not to heat the bulb to a temperature higher than the thermometer is intended to measure. The upper end of a thermometer stem may be warmed over a Bunsen burner if this is done very gradually. When the thermometer i flame, it should be rotated about its axis. ; : ; i ena may be accomplished in cold water, ice, a freezing mixture, or CO, snow, but such cooling should not be attempted while bulb is still hot to the touch. ; a Se ay striking a thermometer on the end must be done carefully at all times and much more so when the bulb is only partially filled with mercury and the thermometer is inverted. This tapping may be “‘soft,’’ as when the thermometer is held vertically and the hand (not the thermometer) is struck on the table, or it may be ‘“‘sharp,’’ as when the thermometer is held vertically and struck downward on a pad of ye Tapping on the side of a thermometer may be done “‘softly”’ with the hand or “sharply” with a pencil. Either must be done with care, as there is danger of breaking the stem. ee ER OHRCDIAC IEDs require different treatment, but the following procedure may serve as a ruide i i i not filled with gas under pressure. igi Se eee ere BOE when it is partially full, hold thermometer vertically, bulb down. Tap ‘‘softly”’ on side near the top and “softly” on end, to bring mercury to lower part of upper reservoir. Then try both tapping “softly and “sharply,” on end, and if this fails to bring the mercury down the stem, warm the bulb until mercury rises and unites with that in the reservoir. Cool very slowly and probably the mercury will all come down. If not, try again, cooling more slowly. . : ‘ To remove mercury from upper reservoir when this is completely full or when mercury persistently stays at the top reservoir, warm er end carefully over a Bunsen flame, beginning at the extreme tip. Mercury will be driven down the capillary by its own vapor pres- lobules are left, warm a little more and they will condense farther down. ‘ ; d cools to a temperature comfortable to the hand. Warm the lower bulb until mercury rises and collects the upp sure. If small mercury g! Wait until the upper en the small globules. : . : wai : is esidual gas in the thermometer bulb, warm the bulb until at least a few centimeters of mercury ap- ae To pee bes ee is oeady hare do not warm. Invert the thermometer and see whether mercury runs down. If not, there pear ae ie cee a the bulb. If mercury runs down, let it run a few centimeters and look for a bubble in the bulb. Right the thermometer part gee eon atier this bubble entirely disappears when the mercury returns to the bulb. If this bulb disappears, no significant amount of gas is present. A into the capill Right thermometer and tap ‘‘sharply’’ vert thermometer and run some mercury into the capillary. Right r p ply id a Se are a of bulb before mercury all returns. .Cool bulb as much as possible, tapping sharply on end when alas ae Se ihee ee and tap very ‘‘softly”’ on end to bring down mercury which is still separated by the air bubble from that in the bulb, Whe this ha come down, either tap “sharply’’ or warm to bring down the mercury from the bulb, but do not let the separated thread a Ti Het i bulb until the main mercury column is ready to join it. Get the two separated parts to join in any conveninet enlargement set nto the upper voir. Right the thermometer or hold it at an angle, with the top higher, and let the mercury run slowly into the bulb, acide eet he point where the bubble is left, to be sure that the column does not separate. If the bubble begins to enlarge, run the mercury more slowly. f : hich filled under pressure, provided there is an en- rom high temperature thermometers, which are p , p n Ear og sets eae Sen 300°C mark). If there is no such enlargement the gas can sometimes be removed by long, ne ai iu pases ne end, or sometimes by freezing the mercury by means of CO, snow, then warming the bulb (from the bottom) pan idipaeatnee tie aad Mercury will not break the bulb on freezing, as it does not expand. Extract from Circular of the Bureau of Standards, No. 8, Testing of Thermometers. 581 ADR: 4 ee UR Fi. T H O M A _§S Cc O M P A N_ Y For convenience, we group our selection of thermometers into (1) thermometers for general laboratory use, in which group we offer three grades: Class G, Class S and Class P, as described under their respective paragraphs; and (2) thermometers for more specific and restricted laboratory uses. Among these are thermom- eters designed for and mostly sold as part of certain instruments. In such instances the thermometers are also listed with the instruments for which they were designed as they may occur throughout the catalogue, and carry the number resulting from such catalogue position. We do not stock the great variety of thermometers made for household, factory and clinical use, other than such as have some relation to laboratory work. THERMOMETERS, GENERAL LABORATORY, CLASS G. These thermometers are offered with stem engraved, with enclosed glass scale and enclosed paper scale. They are corrected for 75-mm immersion, and are accurate to within one division of scale in the interval —10 to 200° C, and to within about 1% in the interval above 200° C, or the Fahrenheit equivalent. These tolerances have been established as reasonable for ordinary laboratory routine, and because of adherence to these tolerances the thermometers are more expensive than the thermometers sold in the trade under the general designation ‘‘chemical thermometers.’’ They are all made under our supervision and in accordance with our specifications. The engraved-on-stem thermometers are furnished with white background and the stemsare approximately 6 mm in diameter. The enclosed glass scale thermometers have a flat opal glass scale and are all approximately 10-mm outside diameter. The enclosed paper scale thermometers are also about 10-mm outside diameter and are of the same accuracy as the stem and enclosed glass scale thermometers, being much superior to the ordinary trade article. Thermometers reading to 360° C and over are nitrogen filled above the mercury. 9525. Thermometers, Class G, Engraved on Stem, with Centigrade scale, otherwise as above described. The 400° C and 525° C thermometers are of Borosilicate glass. Rang Oreos eee oe —10 to 100° —10 to 150° 0 to 200° 0 to 250° 0 to 360° 0 to 400° 0 to 525° Unit of graduation. 1°; 1? 1° 1° J? 1° a Length,mm...... 300 300 350 350 400 400 400 Baehis. j22icct eer 1.10 . 1.25 1.35 1.50 1.60 4.50 6.90 9526. ditto, but with Fahrenheit scale. FRAN GOs ers okra: Seat eeeeret Moder ea ee atk ane eae hs 0 to 220° +30 to 300° +30 to 400° Unit of graduation........... Te eee rs taped he 2° 25 Length, inches................ ee ree reer ee : 12 12 14 Barc hits sys tere Abies neat yee ea 1.20 1.40 1.50 TRANG Chis sere neh oat Mer ee Gh eNO RM Sah. Rina OI ot Gs +30 to 600° +20 to 750° +80 to 1000° Unit of graduation... . en ere ro ne 2° ag 5° Isength, incest. y3:10)5) neat, acts s iGo kee adobe dues 15 15 15 PARR piace ee beeen WAS Resa eb enc iaat A niet Man ae een : 1.60 4.50 6.50 9527. ditto, but with both Centigrade and Fahrenheit scales. Range, in 1° divisions........... —10 to 100° C —10 to 150° C 0 to 200° C 0 to 360° C ar oo, Ce Metis 0 to 220° F +30 to 300° F +30 to 400° F +80 to 680° F Length, inches............... : 12 12 14 16 Boss ARSE etre 1.70 1.90 2.20 2.50 9528. Thermometers, Class G, Enclosed Glass Scale, with Centigrade scale, otherwise as above described. Range, in 1° divisions: 2.24 eccechGhiee des ces —10 to 100° 0 to 200° 0 to 360° heneth: mmc a scehues Sees se Maree Oe sedans 300 350 400 Be i ert Bs eh on en ieee 1.20 1.50 1.90 9529. ditto, but with Fahrenheit scale. Range, in 2° divisions., < w2-ssectued 4 pede pecrne.t 0 to 220° +30 to 400° +30 to 600° Teneth, inches: 5 2s en Mou ft hea leet wee te ee as eA Le ES 3.00 7593. Thermometer for Oil Cup, Abel-Pensky Flash Point Tester. Range 10° to 50° C in 3° divisions. With COTE CALC Sat bie ese ne, Son ste I ERR eh TO een one Pietc RgA RI ti el tris pen cant Onn Ber Lhe, yee 4.00 7594. Thermometer for Water Bath, Abel-Pensky Flash Point Tester. Range 50° to 75° Cin 1° divisions. With COR UEC ACCS 6 erests- sey co sea eas AR acta esp verter we Ey SAUNA SR UO tae ocala & Samal Aca Ah Amu 4.00 7601. Thermometer, Pensky-Martens Flash Point Tester. Range 80° to 250°C in 10° divisions. With certifi- CA LCL A cence antear eats wiaes eg tant cana Met anea Acme a carina AN ee coun mann eae CON Curae ee cS os an BR LR 5.00 7602. ditto, but range 40° to 160° C in 1° divisions, for low temperature investigations. With certificate 4.00 7603. ditto, but range 200° to 400° C in 1° divisions, for high temperature investigations. With certificate 5.60 FLOATING THERMOMETERS, paper scale enclosed in a glass tube of sufficient displacement to cause them to float. Convenient for many laboratory uses. 9578. Thermometer, Dairy, as above described, reading from 20 to 220° F, in 1° divisions. Total length about 8 inches, diameter } inch, length of scale 44 inches. Floats in vertical position............ .85 9579. Thermometer, Sugar Factory, as above described, reading from 0 to 50° C, in 1° divisions. Total length 12 inches, diameter 3 inches, length of scale 9 inches. Floats in horizontal position........ 1.00 Spy Ss SWS el Se wl hus 2 i Shaul = a Siirag anny MTT i SED i S2laa oti te! ariel 9582 INCUBATOR THERMOMETERS. These are specially designed for use in bacteriological incubators and provide a considerable length of stem without graduations, with the scale confined to the upper portion so as to permit reading of the entire scale outside the incubating chamber when bulb is in suitable position within same. It is also a convenience to have a scale larger and more readily read from a distance than is possible on an engraved-on-stem thermometer. For this reason we particularly recommend our No. 9580, which is furnished as regular equipment with our American Standard Incubators. Where it is desirable to have some record as to both maximum and minimum temperatures which have taken place in the incubating chamber, we recommend No. 9581 Thermometer. 9580. Thermometer, Incubator, with very distinct graduations on a white background, so as to be readily seen atadistance. Length of graduated portion 140 mm, length of stem 140 mm. Range from 0 to 50° C, in 1° divisions, with the standard temperature 373° C indicated by aredline............ 3.30 9581. Thermometer, Incubator, self-registering maximum and minimum on Sixe’s system, with opal glass scale 160 mm long, range —20 to 50° C, in 1° divisions. The lower part for insertion in the tubulation of the incubator is 200 mm long. Complete with horseshoe magnet for adjusting indicators.... 6.50 9582. Thermometer, Incubator, specially designed for use with Freas Incubators. With enclosed, opal glass scale, range 0 to 70° G, in 1° divisions. Total length 22 inches, with zero point of scale 12 inches from bulb, so that entire scale remains visible at all times..................0..0. 000.0055 5.00 588 Ar Ro Si Shp u) aR H. T H OF M AS Cc O M P A N Y LOW TEMPERATURE THERMOMETERS. As mercury freezes at about —38.873° C, mercurial thermometers cannot be used for measuring temperatures below this point. For work requiring low readings, such as in the investigations of the melting and boiling points of volatile compounds, gases, etc., and in liquid air investigations, we recommend the following thermometers filled with either toluol or pentane. 9586. Thermometer, Toluol, for low temperatures, engraved on stem; graduated from +30 to —94.5° C, in 1° divisions; 300-mm long and 6-mm diameter... 0... es 6.00 9587. Thermometer, Pentane, for low temperatures, engraved on stem; graduated from +30 to —200° C, in 1° divisions; 350 mm long and 7-mm diameter error ere 10.00 9596 MAXIMUM AND MINIMUM THERMOMETERS. A wide range of usefulness has been found in laboratory work for thermometers registering both maximum nad minimum temperatures, such as are designed and used for meteorological investigations. For use in the interior of the incubating chamber, we recommend Sixe’s No. 9590. Nos. 9592 and 9596 are suitable for any purpose where sufficient compartment space is available. 9581. Thermometer, Self-registering Maximum and Minimum on Sixe’s System. With enclosed glass scale 160 mm long, graduated from —20 to +50°C. The standard temperature of 373° C is indicated by a red line. The lower part for insertion in the tubulation of the incubator is 200 mm long. Com- plete with horseshoe magnet for adjusting indicators................. 00.0.0. 0 2s cc ee. .. 6.50 9592. Thermometer, Maximum and Minimum, on oak back, with each tube mounted on a separate plate attached at one end with a thumbscrew so that the thermometers may be reset. Range —10 to 40° F for the maximum tube and —20 to —60 for the minimum tube, and up to +120°F....... 6.00 9593. Maximum Scale, only, with tube, as supplied with above Maximum and Minimum Thermometer... 2.75 9594. Minimum Scale, only with tube, as supplied with above Maximum and Minimum Thermometer... 2.75 9596. Thermometer, Maximum and Minimum, Standard Weather Bureau Pattern, of high quality and with certificate. With engraved stem, magnifying tube, cylindrical bulb, porcelain strip at side of tube on which are marked the figures and every fifth degree line of the scale, oxidized brass plate, insulating brass support with binding screws. The mahogany finish board is 15 x 5 inches... 15.00 9597. Maximum Scale, only, range —20 to +120°, plain bore mercury tube mounted on 12-inch aluminum scale with insulating support, as supplied with above Maximum and Minimum Thermometer. PWC He COrtIti CA Le xty «wae ea aaa eat nce itn ota) Goes Seamer Seren eat epne seine Aca RIM aks cerca 7.00 9598. Minimum Scale, only, range —30 to +100°, uncolored spirit-filled tube, mounted on 12-inch aluminum scale with insulating support, as supplied with above Maximum and Minimum Thermometer. With certificate. ats sar dga toa ee ia Tea ehhaco le oe ROR UE Me eee are cae eee 7.00 9602 MELTING AND BOILING POINT THERMOMETERS, Wheeler, designed by Dr. A. S. Wheeler, University of North Carolina, to avoid the necessity of making corrections for the exposure of the mercury column in melting and boiling point determinations and in fractional distillations. These thermometers are provided with a short scale, so the entire scale portion of the thermometers is completely immersed in the bath. The length of scale in each thermometer-is 35 mm, and the range of each thermometer is 50°, with graduations in single degrees, while the total length is 200 mm. This length permits suspension of the thermometer by means of a cork, as in the Thiele apparatus, for use in which this thermometer is particularly convenient. See Journal of the American Chemical Society, Vol. 34, p. 1189, September, 1912. The total range of the set of seven thermometers is 0 to 350° C. 9600. Thermometers, Melting and Boiling Point, Wheeler. Set of seven, as above described, in velvet lined CASOS pce a Sah Eee eons 2S SR Aen uenie Ch ies ehed da Reehaa PNe dens com ries Aa eine Leaman han 35.00 9601. ditto, but with Bureau of Standards certificate... 0.6602 47.00 9602. Thermometers, Melting and Boiling Point, Wheeler, as supplied in set No. 9600, for replacement of breakage. Fee Coniesade, nen aee 050° 50-100° 100-150° 150-200° 200-250° 250-300° 300-350° Each, without certificate.. 4.00 4.00 4.30 4.30 4.80 5.30 5.30 MOLECULAR WEIGHT DETERMINATION THERMOMETERS. As Beckmann Thermometers were originally designed for molecular weight determinations, we recommend their use wherever possible. For full de- scription of. Beckmann Thermometers, directions for ‘‘setting,’’ etc., see page 586. 9566. Thermometer, Beckmann, with scale reading upward in 1/100° C divisions. Without certificate.. 18.00 9567. ditto, but with Bureau of Standards certificate. :.ci nice eek $e bie vee ap em enrek cea 30.50 9568. Thermometer, Beckmann, with scale reading downward in 1/100° C divisions. Without certificate. 18.00 9569. ditto, but with Bureau of Standards’ certificate... v5 s.ssnue ade om omen dp RA Smee wise dan .... 30.50 589 A R T H UR H. T H O M A S CG OO MPA UN OY 9570. Thermometer, Beckmann, without auxiliary scale and without mercury pay nadine upward in 1/100° C divisions. Without COnGiiCAbels «Goss ic sous hee fateh a SEN oot SC Ne en rash rec achen 15.00 9571. ditto, but with Bureau of Standards certificate................ a Ree Mep rae faumone nee eee ees 27.00 9572. Thermometer, Beckmann, without auxiliary scale and without mercury trap; reading downward in 1/100° C divisions:., “Wathout: certiiiGa tei: bo Macias ileus oe cece re ng Seco See a Sev eae ek eee oped 15.00 9573. ditto; but with Bureau of Standards certificates «2.5 acca5 an neec he kee Se AeA eked Beene bg aus 27.00 4318. Thermometer, Cryoscope, as designed for and supplied with the Hortvet Cryoscope. Graduated from qelibor 2 Gant: p00 dIVvislons:s. sve secckay cen ae cee Des see Rane Mae ea eee eras 17.50 4319. Thermometer, Cryoscope, the control thermometer as supplied with. the Hortvet Cryoscope in order to guard against excessive super-cooling and the consequent too low convergence temperature. Grad- uated: from-230'to: 30" © an divistonses is ic AG caine deo en cance ae rey ree a ace @ ornate Bite 6.00 7272. Thermometer, Heidenhain, specially designed for study involving the depression of the freezing point. With enclosed glass scale reading in 1/100° from +1° to —5° C. For many purposes this thermom- sa is more convenient than the Beckmann or Differential Thermometer, inasmuch as it requires “setting.” Total length 500 mm. = ardom es es os Renee eeeey 12.00 7273. ditto. but with Bureau of Standards certificate................... SIRs eed en tA 24.00 7274. Thermometer, Auxiliary, for cooling mixture, seiner on stem, range —20 to +40° C in 1° divisions. As used with the Beckmann Apparatus for Determination of Molecular Weight by Depression of the Eres Point, or in the Simplified Cryoscope as cee for physiological and clinical work . Wad siose eicih cle Sleslzra Wher OA oa UR aorta ar gts AN ann Pun AAD ds Ete Bhat Lee eles plan alee ah Rel eer lay sais cesttreige 1.50 a —_ aD siclmelsabesvitay ee SHS ab : Se 7858 0 SEE OVEN AND STERILIZER THERMOMETERS. The requirements for a convenient thermometer for use with hot air sterilizers, drying ovens, etc., are usually those of incubator thermometers in that the stem should be long enough for insertion into the chamber with the scale visible at all times. It is impracticable, however, to combine sterilizer, oven and incubator thermometers because of the different requirements as to range. 7858. Thermometers, Oven and Sterilizer, engraved on stem, specially designed for use with Freas Ovens. Total length 24 inches, with zero point of scale 12 inches from bulb so that the entire scale remains visible at all times. Unit of graduation 1°. TRAN GOS cd vk oekcat a en hiceeaceansatane eaaautan Nes coger Mace tit ite eeceae sa ae een at 0 to 200°C 0 to 300° C CHG ees ay Race EA See EET id aA AN pate ee tare te ee ate a 3.50 4.00 TTA 100_20 9606 9608 POCKET THERMOMETERS. Both Centigrade and Fahrenheit thermometers in a nickel protecting case, similar to that used on clinical thermometers, are convenient for a great variety of field work. For pocket thermometers designed especially for asphalt and sand testing, see page 585. 9606. Thermometers, Pocket, Centigrade, mounted in polished nickel-plated case; 7 inches long, with screw cap, pin and chain. The thermometers are graduated and figured on the stem, and have been found very convenient for all kinds of field work. They are graduated to 1°. RATIO Ose na seat ceeiran i soaee Seong aga Oe eh neat ot pM ben tn a cede: 16 Soe —30 to 50° —10 to 110° ACM ee say A Rn ede react a Aone nedes Seca oa Sere ones enn Rania 3.00 3.00 9607. ditto, but with Fahrenheit scale. Rear Beisel earner als, oe ie edie ae aatha liek aed Aa aoe deena ya Seam Fanler —30 to 120° 30 to 220° Unit7of eraduation j.¢ 0s 2G eke as eee ee epee ot ; is 2° AVC Het ica ss ee Sa de he er Pera ngs eee 2s) Ze ciene- dan Seale ys Ri-zen enna tale eke ts _ 3.00 3.00 9608. Thermometer, Pocket, Centigrade, with inside armor, otherwise similar to No. 9606. Range —10 to PLOS Cs inledivaStONs septa eve es oe Sevag hae Be aliete heel crema aie nes adie ames steele eid one Sa 4.00 9609. ditto, but Fahrenheit scale. Range 30 to 220° F, in 2° divisions.............0.........0.0-4 4.00 599 A R T H U_R Eh. T H O M A 8 Gi sO IM VPs A IN 9612 RECORDING THERMOMETERS. These are designed for continuous seven-day temperature records. They are mounted in an enameled metallic hinged case 10 x 8 x 5 inches, with the internal mechanism finished in silver and bronze plate. The working parts are non-corrosive and arranged so that no lever other than the pen arm is used to convey the movement of the coil, caused by changes in temperature, to the record chart. This construction eliminates all lag, creep and friction, and changes of less than 3° are easily discernible on the curve. 9612. Thermometer, Recording, as above described. Complete with one year’s supply of 7-day charts. 60.00 3. 9613. Weekly Charts, only, for above Recording Thermometer, range 0 to 100° F. Per set of 52........ 50 9614. ditto: butrange:20'to. 120° Bi.. “Per'set.of 52)... cance tna es edt byes RNR Se mci Ge Oe AW ATTEN 3.50 9615. ditto, but range —10 to +90° F. Per set of 52....................... eee Oe 9616. ditto, ruled but unfigured, suitable for range of 100° F. Per set of 52... enfeeemaee ay gees 3.50 9617. Pens, only, for above Recording Thermometer. Each.................. Bet dct este h ter soul un eli 1.50 9b185- “Special: Inks: "Peri Poul ee cece: Seok eee eis Sa Ee a HI eer TE -80 . REFRACTOMETER THERMOMETERS. In this group are listed only the thermometers as regularly supplied with various refractometers listed elsewhere in this catalogue. As the control of temperature in refrac- poeta is most important, these thermometers are of the accuracy of Class ‘‘P’’ thermometers described on page 584. 8623. Thermometer, Refractometer, for use with Abbe-Hilger Refractometers; engraved on stem, range 0 to 80° C, in 1° divisions. Mounted in metallic armor with threaded adapter to fit refractometer. With certificate of the National Physical Laboratory.................0. 00.0.0 00 cee eee 6.50 8611. Thermometer, Refractometer, for use with Abbe-Bausch & Lomb Refractometers; engraved on stem, range 0 to 75° C, in 1° divisions. With threaded adapter to fit the refractometer.......... 2.75 8616. Thermometer, Refractometer, for use with Abbe-Spencer Refractometer; engraved on stem, range 0° to 75° C. in 7;° divisions............. : dynos Annan mem Seed 8627. Thermometer, Refractometer, for use with Abbe-Zeiss Refractometer; with screw connection. Range 0° to TS Ces VI UO AU VASTON So oo 7a ee a es eae ree gd ae ec ryt Ne et AN OF wie eka erm | SEBO! 8637. Thermometer, Refractometer, for use with Zeiss Butter Refractometer; with screw joint for connection. Range: 0to-50° Cain 22 divisions) wAerat caasderink oc cated a mann anunmagwm virgata comeee ease Oso 8638. Thermometer, Wollny, for use with Zeiss Butter Refractometer ; Ree tena Orie bee cere Mibh. COeOD 8639. Thermometer, Baier, for use with Zeiss Butter Refractometer.................................... 7.00 8654. Thermometer, Refractometer, for use with Bausch & Lomb Dipping Refractometer, engraved on stem, range from 15 to 25° C, in 34° divisions, with a red line at 173°....................0005, 6.00 8663. Thermometer, Refractometer, for use with Hilger Pulfrich Refractometer; engraved on stem, range 5 to 80° C, in 1° divisions. With threaded adapter to fit the refractometer............... 4.50 8644. Thermometer, Refractometer, for use with Zeiss Sugar Refractometers; with screw joint fcr connection. Range 0 to:50° Cin:4° divisions .:...:ccis- oes Ha ide doe eee ee eas Wee eS HG aes 3.35 STERILIZER AND OVEN THERMOMETERS. The requirements for a convenient thermometer for use with drying ovens, hot-air sterilizers, etc., are usually those of incubator thermometers in that the stem should belong enough for insertion into the chamber with the scale visible at all tmes. It is impracticable to combine sterilizer, oven and incubator thermometers, however, because of the different requirements as to range. 7858. Thermometers, Sterilizer and Oven, engraved on stem, specially designed for use with Freas Ovens. Total length 24 inches, with zero point of scale 12 inches from bulb so that the entire scale remains visible at all times. BaTiO Os clare oe es SNe Sadan eee So oa Salata ties er AS eae Ae 0 to 200° C 0 to 300° C Unit of graduation. . oe ats ee POS 1 1 Bach. 33.5 het eee Bd uty ceanee Rene Ae ee rarer tate 3.50 4.00 As OR. se GAR: H. Tee ey Oe Me Ay SS C.F eM Po AN: ¥ TAR AND PITCH TESTING THERMOMETERS. This selection of thermometers includes the special thermometers used with the apparatus for testing crude tars, distilled tars and pitches, heavy and middle oils, benzols and light oils, as adopted by the Barrett Company, and described in ‘‘ Methods of Analysis used in The Coal Tar Industry,” edited by J. M. Weiss. See also Journal of Industrial and Engineering Chemistry, September, October, November and December, 1918. Distillation Thermometer No. 1304 is also that adopted for similar tests —D-28-17 Paint Thinners other than Turpentine and D-38-18 Sampling and Analysis of Creosote Oil, of the A.S.T.M. The test number references given refer to those of the Barrett Company, as described in above publica- tions, and those of the A.S.T.M. when mentioned. All thermometers are of the precision required for the test to which they are applied, and are likewise in accordance with the specifications in the above-mentioned publica- tions. 1304. Thermometer, Distillation, engraved on stem, 385 mm long, range 0 to 400° C, in 1° divisions. Corrected for total immersion. As used in Barrett tests C- 9, H-6, H-11, H-12, H-13, H-16, E-5, F-5, F-6, F-7 and F-8; and A.S.T.M. tests D-28-17 and D-38-18.. ee : |. 9.00 1316. Thermometer, Water Melting Point, engraved on stem, 375 mm eae: range 0 6 80° C, in 32. Corrected for total immersion. As used in Barrett tests p- 6, H-18 and E-11................... ... 6.00 1318. Thermometer, Air Melting Point, engraved on stem, 375 mm long, range +30 to 160 ° C, in 3° divisions. Corrected for total immersion. As used in Barveee test DoT... vases es pun ene baccean, 7.00 1332. Thermometer, Benzol and Toluol No. 1, engraved on stem, 600 mm long, range 0 to 200° C, in }° divisions. Corrected for total immersion. As used in Barrett test F-10.... «ts reer eat el)! 1333. ditto, but No. 2, range 70 to 120° C, in . divisions, 300 mm long. : . 7.00 1334. ditto, but No. 3, range 110 to 160° c in ° divisions, SOOMMMP ONG oi. oe sue yaa ee taaeeetnoees 7.00 1352. Thermometer, Limpid Point, engraved on stem, 375 mm long, range —30 to 50° C, in 2° divisions. Cor- rected for total immersion. As used in Barrett COStUH ST Six ic. eas hee kis & prance 7.50 TITER TEST THERMOMETERS. The so-called ‘‘titer test’’—a somewhat misleading name for the determination of the solidification point of the fatty acids derived from the fats and oils—requires the use of special thermometers. Our set of titer thermometers No. 9622 covers the ranges suggested by the chemist in charge of one of the largest soap and fat laboratories in the U. S., and has come into wide use. The certified titer thermometer No. 9623 is made in exact accordance with the F.A.C. specifications in the standard methods of analysis of fats and oils. (See Journal of Industrial and Engineering Chemistry, December, 1919) and of the ac- curacy and general construction of Class P thermometers. 9622. Thermometers, Titer Test, Centigrade scale, En EIER on stem, 12 inches long with magnifying lens front. Range. . ae . E : 0 to 20° 10 to 30° 15 to 25° 20 to ay Unit of graduation : de ib io Baeéhy 2 2 .cs: : ; : 6.60° 6.60 6.60 6.60 RANGE. hk tonnes oaks oes nace 2 : . 20 to 40° 30 to 50° 40 to 60° — 0. to 75° Unit of graduation. . ee ee é : ty to ds 3 Each. SE eR el eee eke 6.60 6.60 6.60 6.60 9623. Thermometer, Titer, with Bureau of Standards eentigenres 375 mm long, 6-mm diameter, graduated at the zero point and in ~° from 10 to 65° C, with auxiliary reservoir at the upper end and another between the zero and 10° mark, otherwise in accordance with F.A.C. EL COUCEDEES: With Bureau OL StanGands:CertiiCabey ca = each dose belie eels Ack Sos Pun ak Saar es bhangra nls Cones 10.70 URINOMETER THERMOMETERS. These are the thermometers Beatie eielied with Squibbs Urinometers. They are furnished in both Centigrade and Fahrenheit scales, 5 inches long, engraved on stem. 3515. Thermometer, Urinometer, as above described, range 32 to 110° F, in 1° divisions. are 3516. ditto, but range 0 to 50° C in 1° divisions Jaen ached oy int alt ne Me acta pNP eceh sre pete ee een a 259 120 wanece 12. PIG cow VETERINARY THERMOMETERS. For taking animal temperatures in laboratory experimentation, the veterinary clinical thermometers have been found satisfactory. They are made with magnifying front and broad mercury column, with pear shaped bulb and glass ring for attaching string as they are mostly used per rectum. The normal temperatures for man, horse, cow, dog, cat, pig, sheep and fowl are indicated. 9626. Thermometer, Veterinary Clinical, as above described. Total range from 94 to 110° F, in 3° divisions. 5 Dnihararul DOr: Casey a Sere vs cs cee ost e co ea Tea nd ctah geo toes a uela opens ee cca) oe ee ered Aue ee ease Ata Pe 2.10 9627. ditto, but with thermometer cemented in metallic cap which screws into the metallic case. The cap is attached to a chain with safety tail clipfor animals............. 00.00.0200. 000 c eee eee 2.25 592 Ay RH ew CR H. T H OF M AS C O M P A N _ Y _ VISCOSIMETER THERMOMETERS. The precise temperature control in the use of viscosimeters requires a special series of thermometers for the various instruments as listed below. 7677. Thermometer, Viscosimeter, Low Range, for Sir Boverton Redwood Viscosimeter. This is the oil cup thermometer; 10 inches long, engraved on stem, range 50 to 140° F, in 3° divisions, graduations begin about 33 inches from the lower end of the bulb. Without the metallic clip for holding in _ position .. . : Smee ee . 5.00 7678. ditto, but high range, 130° to 300° F, in 1° divisions, total length 10 inches; graduations begin about 4 inches from the lower end of the bulb... . is ony a pein ae many Bete ie Dy 6.25 7679. Thermometer, Viscosimeter, Low Range, for the water bath; 12 inches long, engraved on stem, range 50 to 160° F, in 1° divisions, graduations begin about 4} inches from the lower end of the bulb. With slight enlargement below graduations at the point where the thermometer is cemented in ‘ brass fitting which is inserted in the tubulation of water bath : ; “ste a Anh aah DOO 7680. ditto, but high range, 140° to 340° F, in 1° divisions, total length 12 inches; graduations begin about 4 inches from the lower end of the bulb........... mid cos pe (Ae te open en ad a anid eee ak 6.25 7683. Thermometer, Viscosimeter, for Sir Boverton Redwood Viscosimeter, Admiralty pattern. This is the oil cup thermometer, 9 inches long, engraved on stem, range 30 to 70° Fin 3° divisions, graduations begin 4{ inches from the lower end of bulb. Without metallic clip for holding in position... 5.50 7684. ditto, for the water bath; 94 inches long, engraved on stem, range 30 to 70° F, in 3° divisions, gradu- ations begin about 43 inches from lower end of bulb. With slight enlargement below graduations at the point where thermometer is cemented in brass fitting which is inserted in the tubulation of water bath a A bpp ak eR bs bits tae Oana Pein tee cen Ete Ratan dn wale ee trad ite Litera . §.50 7666. Thermometers, Visccosimeter, for use with Saybolt Universal and Furol Viscosimeters, 103 inches long, engraved on stem in 1° divisions, graduations begin 33 inches from the lower end of the bulb. Range. pees A see Yr Pan ees , 70 to 110°F 100 to 140°F 180 to 220°F Each.......... eter er eer ieee 3.60 : 3.60 3.60 7692. Thermometers, Viscosimeter, for use with the Engler Viscosimeters; engraved on stem in 1° divisions, 9 inches long, graduations begin 32 inches from the lower end of the bulb. Without certificate. FRAN PE. 2 ya ine a cue BA rah tral aR) ; 10 to 50°C —-: 10 to 150°C 10 to 200°C Each...... Se Sak Odean rps h cog gh edie eal a) 3.50 4.00 4.50 7693. ditto, but with Bureau of Standards certificate........ 4.50 5.20 6.00 WARM STAGE THERMOMETER. For control of No. 6874 Warm Stage, the most convenient ther- mometer has been found to be an ordinary clinical thermometer as the temperature at which the Stage is operated is mostly body temperature. 6875. Thermometer, Warm Stage, as supplied with Warm Stage No. 6874, 4 inches long, engraved on stem, range 20 to 120° F, in 1° divisions. : nals Men try Ma tas 8, Pi ee cette peaeee ek Saas Sans (25 i AH.T CO 2503 9630, 2504 2505 2758 THERMOMETER READERS. In reading precision thermometers, a magnifying device is frequently convenient. Those listed below have been found satisfactory for the purpose intended. 2503. Reading Device for Beckmann Thermometers and Burettes; with glass plate... ..... Baaas --. 1.00 2504. ditto, with quick-acting spring clip and focusing lens. Gives an unobstructed view and is a most satisfactory form.............. SAL Saat shhare asa toa SEs Sys A cee Bid SE ga Fess! sear ttinter: 6.00 2505. ditto, consisting of magnifier on spring clip............. 3.00 9630. Reading Device for Thermometers, with quick-acting spring clip and focusing lens. Gives an unobstructed view and is a most satisfactory form. The clip is of small diameter for stem aes OTALY ay scocsanscoecse Gi eat Daied Posen Seles Meee CER AE Me mtn eee ahs lem eatin an SUES d 2758. Reading Device, for attachment directly to the stem of thermometers. Suitable for thermometers up to and including 9 mm diameter................. Aig ee Ree CE RS SN ... 2,50 In our Code Index and Condensed Price List will be found a code word for each size of every item in our catalogue, with the exception of Reagents, which are coded in the listing. The use of this index in the preparation of order lists will be found convenient and time saving | by those familiar with our stock because of the brief description of apparatus and prices which have been included. Separate printing of this Code Index and Condensed Price List provides a method of pub- lication of rigereant price changes between the editions of the catalogue and it is our in ention to re-publish it as often as may be necessary during the life of this edition of our catalogue. | Cable Address, “BALANCE,” Philadelphia. Codes: A. B. C., 5th and 6th ed., Marconi, and Bentley Improved. | A R FT H UR H. T H ©O© M MenRCUn yaa ey cere fica soe ceed in Ser cee mc eet ber ONG eR ea ane acre faint ute ORC oar cA bition 16.80 9644. Thermo-regulator, Harvey. operating on the principle of a Beckmann Thermometer. An auxiliary scale reading from —20 to +250° C aids rapid setting. The lower platinum contact is made in an en- largement of the capillary to avoid sticking of the mercury at this point. The upper contact is so placed that small temperature changes will make or break the current. The mercury column is of sufficient diameter to carry the current required to operate a 150 ohm relay using 2 to 4 volts. The heating circuit should be broken by arelay. The author secures regulation to within +0.004° C in an air bath. In size and general appearance the instrument resembles a Beckmann thermometer with the addition of the necessary platinum leads and terminals. See R. B. Harvey, “‘A Thermo- regulator with the Characteristics of the Beckmann Thermometer,” Journal of Biological Chem- ISU ORO NUATY ae LEO 2 Oa tebe iN orld cae le Nana eR nya Ad Sets Satis cn NWN eel Nhe ates Ara in AR te Ale 15.00 Directions for Use of Harvey Thermo-regulator. Warm (or cool) the mercury bulb until the desired temperature is indicated und transfer the excess mercury to the right limb of the reserve reservoir. Should the mercury column break lower than desired, grasp the instrument near the bulb, holding it horizontally with excess mercury in upper bend and tap it sharply, causing small droplets to separate from the main reservoir. Transfer these to the main column by tapping the instrument while held vertically. Repeat asrequired to bring column slightly above the upper contact point. Bring the regulator to the desired temperature by immersion in a water bath. Grasp the instru- ment at the top, holding it horizontally and break the column at the upper contact by a sharp tap immediately below the upper contact. This excess mercury is thrown into the right limb of the reserve. Do this quickly, so that the temperature may be changed as little as possible. 594 A RR TF HOUR H. T H O M AS Cc O M P A N Y PILOT LIGHT ADJUSTMENT. 9655 9645 9646 9650 9651 9545. Thermo-regulator, Improved Bimetallic, Gas, with diaphragm arrangement providing for considerable increase:in sensitivity. Range Up-t0: 175° Cie coiss caw wceuians wong by oud oR Reno cm Mahou ee. 15.00 9646. ditto, but electric, with platinum iridium points in place of valves. Maximum carrying capacity tZey Wattss-Range up) to:2 00? Caco vanity ecbdie ws nel Mee 2 an hud thee one engages ia bi, ese 15.00 6022. Gas Filter, for use with either the Greenman or the Roux Bimetallic Thermo-regulators, to clean the gas of coal tar or other impurities, thereby securing more satisfactory working of the regulators... 8.00 9648, Pressure Regulator, for use with gas thermo-regulators where variation of pressure exists in the gas supply. Delivers gas to the thermo-regulator at constant pressure, thereby greatly increasing efficiency of same. Particularly recommended for use with No. 9639 Gas Regulator. Made of COPPer throu nOutye cov. son ces eed IN RUAN NE peta te oy Ao cers inca nag enone hans Reem Ei eta eee 13.60 9650. Thermo-regulator, Toluol, simple form as used for temperature control of baths in conductivity work. 2: W BE OUG AIMEE CURVE scan eec as ne tes Sts tec Oe ares RON A oOd Seisgs Coe tana elena 6 enters mig te tara acest ai 00 9651. ditto, improved form, with by-pass and stopcock.............0..00000 00 ccc eee 5.50 9652. ditto, i. e. with by-pass and stopcock, with binding posts, and contact for electrical connections. 10.00 THERMO-REGULATOR, ELECTRIC, Mast, for use in connection with any form of electric lamp or stove as a heating unit. The apparatus consists of a tube, one end of which is extended upward to carry the operating mechanism. The regulator is furnished in two forms, one with a single, straight tube of small bore widening into a well at the bottom, and the other with a double U-tube. In the first form the tube is filled with mercury, in the latter with glycerine, alcohol or toluol, and at the top with mercury. The mechanism in both cases is the same. While the second form is naturally more delicate, it affords a very sensitive control, which, under favorable conditions, does not vary more than ;5 of one degree. A cork float on the surface of the mer- cury is connected by a fine rod with a movable crosspiece which closes the circuit to the relay, or switch. When the temperature of the incubator rises, the expansion of the glycerine and mercury raises the cork float, which closes the circuit, causing the switch to open and the heating to cease. With the ensuing fall in temperature the float drops, causing the circuit to open again. 9654. Thermo-Regulator, Electric, Mast, Simple Type, as above described......................000.. 9655. ditto: bub. doubledUtuberty pe sxsc.wirs sen c cece dunes Wat aes Eas are ep nen GO aiaE EN Coe inrenee 9656. Thermo-Regulator, Bimetallic, Electric, C.S. & E. No. 46, consisting of a thin, metallic tube 6 inches long by 42-inch diameter, hermetically sealed at bottom for immersion in water baths, etc., and contain- ing a sensitive bimetallic bar which extends from the bottom halfway up the tube. The contact points are protected by a condenser, which kills the electric spark, provided the electric current passing through same does not exceed one ampere. Range of temperature 30° to 70° C..... 13.00 Thermo-Regulator and Heater, Electric, C. S. & E. No. 29, similar to No. 9656 but in combination with electric heater for water baths. The heating disc is 5 inches diameter by }-inch thick. Complete outfit includes thermo-regulator, pilot lamp, cord and plug. Maximum current consumption, 1 AYN DOLO! cst dcp susklics Peas akdes occa 0s Gd rue ew he een erecta a cece erties at oon aE Rg ee Us 36.00 9657. AD oR 7F He Ue R H. T H O M A SS Cc O M P A N _ Y 9660 9662 9664 psfam <<< cc = 9676 9660. Thermo-Regulator, Electric, in combination with electric heater for incubators not exceeding 3200 cu. in. incubating space. If the incubating chamber is well insulated, it will maintain a reasonably con- stant temperature of 373° C. Thespace occupied by the device is 43 inches by 8 inches by 8 inches. Maximum current consumption, 1 ampere. With carbon filament lamp as mons element, mounted on base with No. 9662 Thermo-Regulator. For 110 volts... Breen a et on An erie bk aes 16.00 9661. ditto; but for 220'violtsic. cscas ek aoe Ree skew gone owe es Sev ae Now renee ah kia or, 16.00 9662. Thermo-Regulator, C. S. & E. Patent Electric, No. 5; with a range of from 30° to 60° C. With condenser which protects the platinum contacts from destruction by arcing, providing the current does not exceed 3 amperes. Space occupied approximately 7 by 53 by 2 inches................... 13.00 ELECTRIC THERMO-REGULATOR WITH HEATER, C. S. & E. No. 48, for use in incubators, paraffine baths, etc., and as regularly used in the C.S. & E. line. They can be used for the heating and regulation of any utensil to either 373° C, for incubation, or 56° to 60° C, for embedding, inactivating, etc., providing the cubic contents of the utensil is not in excess of the figures given, the only difference being that for the higher temperature the plates are supplied with more heating units. The15 by 15 inch size will heat up to 10,800 cubic inches; the 93 by 93 inch size will heat up to 2000 cubic inches, and the 84 by 63 inch size up to 1000 cubic inches. All are 7} inches high. With pilot lamp, cord and plug. 9664. Thermo-Regulator, C. S. & E., 15 x15 inches, for 37-4 °C with 4 heating units. co... 34.00 9665. e by 15 x15 et 56- 60° C 6 eee ce 36.00 9666. “ “ i 93x 92 “cc “c 37-42 C 9 “cc ce 24.00 9667. Zs 93 x gi a ae 56-60° Cy “og ee Bie Sha AMEN ite 26.00 9668. i - ne 8ix 6 “ Me lea Ry 2 “ Cee ade cia ei 29.00 9669. e "7 e 8ix 64 “ “ 56-60° C3 ms 30.00 ELECTRIC HEATING PLATES, C. S. & E. No. 47, of transite, with connections and heating units, but without thermo-regulator. The plates are all 12 inches high. Size 15 by 15 inches is intended for use in Incu- bators Nos. 1470, 1471, 1473, 1474 and 1475, two plates being required for Nos. 1474 and 1475. Size 93 by 93 inches is for Incubator No. 1515. The heating plates for temperatures 56° to 60° C, are identical with those for 373° C, except that they have more units. These plates for use in utensils other than the regular C.S. & E. line are supplied with thermo-regulator attached, and are listed under No. 9664, etc. 9672. Heating Plate, C. S. & E., 15 x15 inchesfor 37-3} °C with 4 heating units. . senesced 12.00 9673. a i . 15 x15 a “56-1 60° G 6 site ste gieate F400 9674. a ws 9x 91 “ “ 37-4 °C Senn oy Soh lapse acetone UO 9675. os i " OF eo oe 7 56-60° Gye 4 SEO. pain: wih sens, OO 9676. Heating Unit, only, C. S. & E. No. 44, as supplied on No. 48 Thermo-Regulator and Heater, and No. 47 Heating Plates. A lava composition rod with brass terminals; over all dimensions, 3 by 3 by 12 inches. Maximum current consumption, } ampere on 110 eles eer ct eee 1.00 596 7812. 7813. 7814. 7816. 7817. 7818. 7819. 7822. 7824. Thermo-Regulator, A. & S. Electric, Type SB; a regulator of the expanding capsule type which is of the simplest possible construction for small apparatus not requiring over 3 or 4 amperes for heating. It is furnished with iridio-platinum contacts that will not stick, and is mounted on a transite base 4 x 4 x } inch, with stem and holder for capsule projecting 4 inches, i. e., for use on any utensil in which the aggregate thickness of insulating jackets in less than 4 inches. Where this is longer than necessary the stem can easily be cut off, and longer stems can be furnished on special order. When the thermo-regulator is to be attached to a one-inch tubulation, as frequently found on incubators, a clamp should be purchased. This thermo-regulator can only be used in a vertical position. The expanding capsules for use with this thermo-regulator are listed under No. 7x22, and when ordered temperature range should be given. Without expanding capsule or tubulation clamp.... : : Be NALA Re nsf toy ai ra sateen Say wig ee ey Fe we SPR 12.60 Thermo-Regulator, A. & S. Electric, Type A; an expanding capsule regulator similar in design and con- struction to Type SB listed above, but for use in conjunction with Magnetic Circuit Breaker carry- ing currents up to 10 amperes, which combination makes a most satisfactory temperature control. This thermo-regulator can only be used in a vertical position. The expanding capsules for use with this thermo-regulator are listed under No. 7822, and when ordered temperature range should be given. Without Magnetic Circuit Breaker, Expanding Capsule or Tubulation Clamp..... 10.80 ditto; but-for use ina. horizontal ‘positions: 242 .a¢ea swede pee ese i yeaee erie ees REM A 10.80 Circuit Breaker, A. & S., for use with Type A Thermo-Regulators. With large iridio-platinum contacts that will not stick when not overloaded. The contact is raised magnetically and falls by gravity. The solenoid is well built and guaranteed not to burn out when used on proper voltage. A con- denser is supplied for absorbing the arc at the points. Without thermo-regulator. For 110- VOL OSC = ante kan theises Ro eine at dead ene BA itp Nr cot RE SE Mi tena co ee wae oe dee phate ergs Cenc ates ; sea deca 21200 ditto, but fors110-volt, G0=¢y cle canGi: case cand nin wills SEe AAR sR Ad ok opie eo ene sn suen oan 2200 ditto, but for 220-volt d.c.. gett becdes So eral 1c MeN VR ay renee te Redeeg eer ox, ..., 24.00 ditto, but for 220-volt, 60-cycle, a.c......... es ier nae e tore arches ener here Py, Sod mer Rest ON Neca are 24.00 Expanding Capsules, for A. & S. Thermo-Regulators Type SB or Type A. These capsules are 31-inch diameter, with stems 4 inches long. Stems can be shortened if necessary. * Extra lengths can be supplied on special order. Temperature range, centigrade....... 0° to 30° _ 30° to 45° 45° to 60° —-60° to 160° Each......... ote ialeas et naa 1.20 1.20 1.20 1.20 Tubulation Clamp, for use on either Type SB or Type A Thermo-Regulators, for attaching same to tubula- tion of drying ovens, incubators, etc., up to one IN CHS AM CTE T steer eek one eed Seana e b2e8 Foes 2.40 9684. 9685. 9684 9685 Tongs, Crucible, double bent, of steel with black oxidized finish; 8 inches long. Recommended as the ‘most satisfactory, low priced tongs for student’s use... ..- 6-6-6262 eee eee eee 25 10% discount in lots of 12. 20% discount in lots of 144. i bent, of steel heavily nickel plated; 20 inches long. Superior in workmanship ae ie ne heavy tongs for handling assay crucibles. Convenient for handling dishes in deep tautleS.cnp eet vies vase Keene te ose tend ase DRE Ry MESSE ds 3.00 9690 9694, 9696 9686. 9687. 9688. 9689. 9690. 9692. 9693. 9694. 9696. 9696a. 9697. 9698. 9699. 9700. 9702. 9703. 9704. 9705. 9706. 9707. 9700 9702 9707 Tongs, Crucible, double bent, of steel wire, flattened at joint and tips; 9 incheslong. Very serviceable, but not so stiff and rigid as the cast and Wrought; ton gsi o% 25 a hie eR Sen a-weieine pay sake RES 35 ditto, OM DTASS ie 0 syria kieran hones woh cet oa namie ar 8 Uae i nia ate ee a acetates he ON dy atin ed dried Miacahes 50 Oe) eG SNICKElSPlAeGat se Ae ag cnc’ ssa ac IN tina Sal ate ora nana ok ies on hae ee Ba aeons .80 «© golid nickel .......... be Least renee Pc hey losem ta ate ea ece arch amen iene eaten RNa eee seem: LOO 10% discount in lots of 12. 20% discount in lots of 144. Tongs, Crucible, double bent, of Chromel wire, flattened at joint and tips; 9 inches long. Recommended because of the non-corrosive properties of this alloy. . eee Ae ease AOSEO Tongs, Crucible, double bent, of polished cast brass; 8 saches jane: ‘With Aeeunately adjusted jon and tips. Of superior workmanship and finish, and more rigid than tongs poemued from wire... 1.00 ditto, nickel LAC CC Si Sa gee ee te ttt vcs once Ste ecm os Sealant 1.25 10% discount in lots of 12. 20% discount in lots of 144. Tongs, Crucible, double bent, of wrought steel, heavily ietel plated, with accurately adjusted joint and tips. Of superior workmanship and finish, and more ciate than tones pian from wire. Length, inches.................. paneer AN NTE a Whur betereny races 9 12 Each. UES cated SAR RMU NURS eA ute .... 1.00 1.50 10% discount in lots of 12. 20% discount in 1 lots of 144. Tongs, Cristie, of solid wrought nickel; 8 inches long. With accurately adjusted joint and tips. Of superior workmanship and finish, and more rigid than tongs stamped from wire............ 2.50 ditto, but with solid Chromel tips securely riveted in position. As Chromel does not fuse with Platinum these tongs can be used in place of Platinum tipped tongs. Recommended as the most satisfactory tongs in-our assortment. . Z NTN Ae MEN See, Oe Ads ety Rs 3.50 ditto, but with platinum shoes, weighing about 5 | grams per pair. ““Approximately.. i pee seeak rare S200) Tongs, Crucible, of heavy malleable iron, single bent, for assay crucibles. Length, inches 12 17 IE ACH regs ects eatin ins eae ge aes pee Baten vant Oana ieee Ae or haee ohn ia I8 a MiNi kE Daas 1.25 1.80 Tongs, Cupel, of steel with curved ends and guide pin; 22 inches long......................0-4. 1.60 Tongs, Cupel, of steel with bent ends and guide pin. Length, inches........ 20 25 30 ACI ere ee sk ng ee ea ee .. 130 160 «1.75 Transference Apparatus, Findlay. An improved model providing for the drawing off and analysis of the intermediate solution contained in tube C, as well as for the anode and cathode solutions. See Alex. Findlay ‘‘Practical Physical Chemistry,” 1917 ed., p. 211; censisting of glass parts A, B, and C, complete with rubber stoppers, rubber connections, pinchcocks, and platinum electrodes 15.00 Glass Parts A, B and C only, without rubber ste connections or electrodes, latter to be supplied in the laboratory. Per set of three tubes. . ose Ri Nes un oh ARUN Aas SOD a Conn ee pater OO Glass Tube A, only, with ey Nene eee eRe re eee Pe eg a pxacace 14200 “cc “c“ C, “a “cc “cc : 4.00 Glass Tube only, as shown in B' for use in Findlay "Transference Apparatus where a gas is evolved at the cathode. In this proceeding, tube B is replaced by B', mercury being used as a cathode. With bent tube for mercury cathode, but without rubber stopper, mercury or wire connection..... 6.00 598 9708. 9712. 9713. 9714. 9715. 9716. 9717. 9720. 9721. 9715 Transference Apparatus, Washburn, for the measurement of transport numbers by the Hittorf method in solutions of the halogen acids and their salts, consisting of the modified form of the apparatus used by A. A. Noyes in his investigations of transport numbers of the alkaline earth metals. See Journal of the American Chemical Society, Vol. XXIV, 946 (1902). The apparatus here listed is a somewhat simplified form of the apparatus for precise work described by E. W. Washburn The Migration of Ions Determined by Transference Experiments in the Presence of a N on-Electrolyte, Journal of the American Chemical Society, Vol. XX XI, 322 (1909), and is primarily intended for student’s use. Bore, 16mm. Without electrodes............................0....... 32.00 Note—The precision apparatus for research is supplied on special order only. Trays, Aseptic Enamel Ware, of seamless steel white enameled. Convenient for dissecting instruments, syringes, pipettes, etc. Size, inches............ geo eerie ema he 8;x34x14 163x31x 22 Breet ee A oe eran aesier enema Mane anced 95 «280 Trays, Aseptic Enamel Ware, of seamless steel white enameled. A wider form of tray, also convenient for dissecting instruments, etc. Size, inches................. 8x10x 2} 10x 15x23 ACH ees ee ie rancor oti hoe acc Meas OE oes ee aa ~~ 4.20..~—SOSO™*~*~”:S BOD Trays, Aseptic Enamel Ware, of seamless steel white enameled. Very convenient for small dissections, handling of specimens, organs, etc., in autopsies, etc. Sizes An CheS Sect aero cervorice gay dt pee SHUR Meni eae Aran has 93x 1383 114x152 122x192 Baehts.83 niocets aaa ei ies Reha a nese a salar Mags ae ae 1.30 1.35 2.00 ditto, but somewhat deeper. Size, 163 x 203 inches..............0 0.000... cee. 2.20 Tray, Dissecting, of heavily tinned metal, japanned, with metal loops at the corners to which the limbs of animals are tied during dissection. Melted wax may be conveniently run into these pans inthe laboratory if wax bottom is desired. Size, 11x 9x 1zinches.....................0........ -40 Trays, Glass, with slanting sides, as used for developing trays in photography. Size, inches... cur. aie ie Ree oe a ne spade vee eae 4x6 53x 8} 7x9 8x104 Biyclitsak toconn tt eae ctek ety as ch a ame etl ns ere A pe en tae 35 50 75 1.00 Triangles, of iron wire covered with pipe stem. Length of side, inches....... a a Barc lise eo ese hee BGR SR Sear are sh ha eri meee 10 .10 10 Per dozen. ........-.06++++55: ome aes Sed seeders ner dese rach -60 .60 .60 10% discount in gross lots. 15% discount in 5-gross lots. ditto, but flanged in center. Length of side, inches................. Aa ee eee POW ss eR ee A ae ER EAE PRR PERE AOE EES es 10 10 10 PEK dO ZENS his a a ates AIS Ue aac REN OIE Sig RE RE eAt -60 -60 .60 10% discount in gross lots. 15% discount in 5-gross lots. 599 9723. 9725. 9730. 9731. 9732. 9732 Triangles, Chromel Wire, of heavy wire of square cross-section and distinctly superior to triangles made of other market alloys of nickel and chromium. The alloy of which these triangles is made contains no iron and takes on a thin, adherent, protective coat of oxide which neither peels nor rubs off and which prevents the triangle adhering to platinum ware placed upon it. Length of side, inches. . BESTS are Ate irra seo puperr eas eee ree 13 2 Qh 3 Each: enone oak EU eee oe erica tac wt TN PI Ae “28 28 + ©«.40.~«.40 Triangles, Chromel Wire, covered with opaque silica, glazed. Length of each side, inches................. 3 2 22 3 33 4 TC oe ek a Ritsaknie a eho -50 -50 -70 .80 -90 1.00 Triangles, Opaque Silica, glazed. Length of each side, inches................. 14 2 2 3 32 4 FeO GSE SE POR 1.50 1.50 1.75 2.00 2.25 2.50 Triangle Holder, nickel plated, with clamp for attaching to support. Adjustable and suitable for use With platinum OF CHROME WILeiiss 215 chee ys es ne Ge Secon

a 9780. 9781. 9784. 9785. 9786. 9787. 9788. 9789. 9790. 9791. 9792. 9793. T HH UR He T H O M A S Cc O M P A N_Y Turbidimeter, U. S. Geological Survey type, as used in water analysis in connection with water plants, filtration installations, etc., as described in Bulletin 151 of the U. S. Geological Survey, and Bulletin 8 of a the Division of Hydrography. Complete for color —s and turbidity, consisting of four aluminum color : tubes, six amber glass discs mounted in aluminum and graduated, flexible metallic turbidity scale; 9776. (am mB i packed in morocco-bound wooden case..... 56.00 9777. ditto, but without case...................... 53.00 9778. Turbidimeter, same as 9776, consisting of the outfit with the exception of the Turbidity Scale. With CASO erat ae tacyi ew heen Are vacate Contd Cueaey tan ek Boe es 49.50 9779. ditto, but without case....................... 47.00 9776 ‘Turbidity Scale ionly< with casex3 2:2 Vata ep ka hee oe ae eas Sanoeieamatat wna ie erie 9.00 ditto without, case 26 tors oc mrt: all 5 ohn eater ia iy eA ee ear See ee Pee Ae i 8.25 9786 Ry j / a @

18.75 9814. Single Range Ammeters. Amperes...................0 2.000.002 .02e eee 1 5 25 Boa Clie ed te cies ty a es RM Cs NS ey Sas ae ean ey adele 18.75 18.75 18.75 9815. Double Range Ammeters. Amperes...............0.0 000 cece ee 10-1 25-5 DEV Tis ae se eet ho es eater cae ees ted AAD Paha At Geen eae ad ea ete emer ora oe Shehunes Rn oe 21.75 = 21.75 9816. Triple Range Ammeters. Amperes....................00-....00--..0000.. 5-2.5-0.25 20-4-2 Fs re Act eee ah ie ee rte ened magne wane Alm Des an kta Ok 6 24.75 24.75 9817. Single Range Volt-Ammeter, 1.5 volts... 0.22.00. cae 28.50 9820. Volumeter, Scott’s, designed especially for the use of paint chemists, for measuring the weight of one cubic inch of powdered material. So constructed that the measuring receptacle is filled by gravity. the height of the fall being constant and regulated by a series of glass baffles, eliminating the varia- tions due to the difference in the technic of various operators. Complete with one cubic inch and COUNTEEDOISE Ap ten cia 24.85 Sheet e MeO WA ait Afile DR AMinene Soho mia Gnas aiyaditon leet ediarmmbucna Meenas 24.00 9821. Cubic Inch and Counterpoise, only, for above..........0...00..00 00 5.00 1805. Warming Table, Huber, with top of heavy copper, 14 x 4 inches; ‘for fixing blood films, drying micro- BECEIONS CEC seuc ernss tare hte eae Seva iene Ane Nay Nats preeeaaece NT tere ah ceete, ooaad Cit yn it Serine ays 2.15 1806. Warming Table, for embedding objects in paraffine, consisting of a triangular copper plate 16 inches long by 73 inches wide at the large end, with small copper box for containing the paraffine. By heating this plate at the acute end, varying degrees of temperature are readily obtainable throughout the length: of the table. 4 aca cuseeew peseneeess es ee mn a he OS arma na oahs Hoe Wee wes 3.50 9824 9825 9828 9830 9824. 9825. 9826. 9828. 9829. 9830. 9831. 9834. 9836. ANTCO Ses Washing Bottles, of Pyrex Glass, with flat bottom and heavy ring neck and with woven rattan cover over the entire length of the neck to protect the hand from heat. Because of the remarkable me- chanical strength of Pyrex glass, its resistance properties and the rattan cover, this combination makes the most satisfactory wash bottle obtainable. Complete with rubber stopper and glass tubing: Capacity; mln. soe). chats sonal g etek ec aya cee Nae Sed nAcn he Nis 500 1000 Says Each cee cs. stearate 2 Rival ware ts Ecole ata hesldlarh eave Bek GMa ana ie pass rns Sia, et eiirhie 1.60 1.80 Washing Bottles, consisting of a No. 5328 Pyrex Flask, rubber stopper and glass tubes. Capa Gym ley ake ela a et cae rh mela ht Re ar eR a neste oh Sena Ae 500 1000 2000 ae BA CIV ces sige Oe AN corte mn ep Rare ha Oley ot oe Aer ee RR -60 .80 1.05 Fittings, only, for Washing Bottle No. 9825, i. e., rubber stopper and glass tubes without flask. Loft bottle; capacity mil: «kiss pti codec eS A cies ru eke cmatnwdtire ean ogets 500 1000 2000 Rubber Stopper:-SizeuN Os. wo eke eons eee ete baw ee pean dete ; 6 qT 8 Perisetiie cect eet eS a vee cen Poptart Smart eae ices Se -20 25 .30 Washing Bottles, Faraday, consisting of a No. 5328 Pyrex Flask, with two-hole rubber stopper, and glass tubes with rubber joint in outlet tube to give flexibility. Capacity snl ites oe arc oor aren oe il os ane Met hs igh Oke ok vim thio ae saeneh 500 1000 2000 EACH erence Aaa eict Nr Sn be cneets eho, ise canes cocina Gy tile Sraanant tan ak .60 75 1.10 Fittings, only, for Faraday Washing Bottle, i. e., rubber stopper and glass tubes with rubber joint in outlet tube. To fit bottle, capacity, ml......................0..00.. 500 1000 2000 Rubber Stopper, size No.............. 00 cee Drateeatt z 6 7 8 POR SOU aero aecty sects aaa Bede SAN SV ROR Acc vis EN nv eel BPH ie AR Sart ee eo ed 25 .30 35 Washing Bottles, for volatile liquids, with ground-in glass stopper. Capacity. Walicy otis ga ain os avo av en Aen meen ah dee RNG RANE 150 300 500 1000 a ae reo ica ee lant Veh a Nee et eee een een eal Nd sb MNS -90 1.20 1.40 1.70 Washing Bottles, for volatile liquids, with ground-in glass stopper and two glass stopcocks. Capacity, ra ssie to ote eae oe eee ee AN TIA ORs Rena ots 250 1000 5.10 9834 9836 Waste Pail, Aseptic Enamel Ware, of seamless steel white enameled, both acid and fireproof. Very con- venient in the laboratory. With perforated tray which retains the solid matter such as filter paper, etc., which may be lifted out before the bucket is emptied; 16 inches high by 12 inches diameter, 5 gallons capacity... 00.0.2 teens : 10.00 Watch Glasses, of well-annealed glass, with edges smoothly ground. These are made especially for laboratory use and are superior for this purpose to ce me Cg Bane in the watch and clock trade. Diameter,mm................ 15 90 §8100 ‘ ciissemuie:. A 2 28-675 Ss 00 re pie Seats - . ee Sie natant 6.50 6.50 9.10 9.10 10.10 10.75 12.50 Dhaiet Or traps Gate teen eis eons 115 125 140 150 165 175 200 HLS fue eco een a et 15.16.20. +238 +26. +30 40 Pan dgaei os ed ee 135 155 175 2.05 2.30 2.70 3.45 14.40 16.60 18.75 21.90 24.50 28.80 37.65 9839. 9840. 9841. 9842. 9843. 9844. 9845. 9846. 9847. 9848. 9849. 9850. 4 z= has (0m Watch Glass, with concave center and a small facet on the bottom; 45 mm diameter.............. 10 Watch Glasses, in Pairs, with edges accurately ground together, for use with clamps. These are not to be confused with counterpoised watch glasses No. 9840. TIA MOTOR: MANN banat eine teeth ee Acs Aha) Ah tig oe oes hea notion en ad RENNER Ge 50 65 CT and ees he ae eet eae Nae ane Pie ne one ei ON Aen Sad RE ere 25 .30 ditto, but with clamps No. 3262. Dare bers Ws che 58 a ore a ee tk hee De a pd ede A ae i oon Atk tan ale ty Beet Te 50 65 POr pally oi Moen eres ee pe tea Sete en gen] eee Nel Sh oe Pes eae 55 -70 Watch Glasses, Counterpoised in Pairs, accurately adjusted for interchangeable use on balance pans. Wianretercmimiyes te) each Su eile octet irae Wma Baht aud Seth gc en ecethins aoe noone 65 15 WP CR Dab he fo vet 20 oi etree Pile ed hands BRA ONE CI etn Nicht Ah eS NS neh eee h tn a SER gk (TMI eet eee ret es 75 1.00 Watch Glasses, Split, with small opening in center. Convenient for covering beakers, etc., with stirring rod in position, as in stirring and electrolysis apparatus. IDC SL AMI renee core epee area poy mar rere eared ue, Att Se at dU RAG CRI can BOs een a 15 100 acho (wo halvies) ss sco panee fase noveh ol uence Be IO eee : 15 -20 Watch Glass, Embryological, of white glass 13 inches square with concavity 14 inches wide by 2 inch deep, and with one vertical surface ground for writing upon. The bottom of the concavity is fairly flat but with mold finish, 7. e., not polished. Without cover........................ 15 Glass Cover, for above, 14 inches square, with edges ground..................0.0 00000 e eee 10 Watch Glass, Embryological, of polished plate glass, 40 mm square, with spherical concavity 32 mm diameter by 8 mm deep. With one vertical surface ground for pencil inscription. With vee DIALESO ASSN COMED RAM hahaha iy cn Aina a ere cA aetaeee ac ag Sieh Rees hein aha th Sate eo eae ne nee Ss ea ditto, but of polished black glass; very convenient for the examination of small embryos....... = Watch Glass, Embryological, made of a single piece of polished plate glass with concavity with flat polished bottom and plate glass cover; concavity is 30 mm in diameter by 6 mm deep; the flat polished bottom permits its satisfactory use on the microscope stage.......................0..... .50 Watch Glass, Embryological, of glazed white porcelain 30 mm square with concavity 21 mm in diameter, WIEH OUT COVER: 455 escent cinta anasiee essere tna in eek ak eae AP eRe te retacncet de SAN Ee Met toca -40 Watch Glass, Syracuse, 23 inches diameter; a convenient and widely used form of watch glass for biologi- cal work. Convenient for stacking, in which case contents are thoroughly protected from dust. Without imprint or trade-mark moulded in the bottom which interferes with use of the glass. .12 10% discount in carton containing 12. ditto, but with beveled surface ground for writing upon 10% discount in carton containing 12. sy nse bed sede se Saw io rd eS ae ATEN BE Ay Be lal 25 Watch Glass, Bureau of Plant Industry Model, similar in cross section to the Syracuse watch glasses but of smaller size. The flat bottoms are ground and polished both inside and out. The bottom sur- face does not come in contact with the table or microscope stage, and the grinding of both top and bottom edges makes accurate nesting possible. The beveled surface is ground matte for convenient writing; 8 mm high by 27 mm diameter. Each..................0 00.00.0000 0.00 cece ee 50 Per @oveitn 4 nc dks Ae oe tence 5.00 Per gross 608 A R T H U_ R H. Te kl OF My eA Ss C O M P A NY ae yy J 9866 9864. We aths ‘ a . ater Baths, of heavy copper, tin lined, hemispherical form, with concentricjrings, cover and steam Each. Diameter, inches................. 4 5 6 8 10 12 ee at {e,discount in lots of 1. Laat I 120. 135 1.90 3.20 6.00 10.65 Diameter, inches... .. : ee a : ee oe eee 6 8 10 iio acetone, 6 erred eaiea ae soa 9866. Water Baths, same as No. 9864, but with constant water level Diameter, inches......................... sie 5 6 8 10 12 Daas iia ic vod ratt esi ei een eR Gat 2.40 2.55 3.10 4.40 7.20 11.85 9868 17 Wa oT a LE | 9869 9870 9871 9868. Water Baths, of cast iron, white enameled inside, with flange for supporting on tripod, and with copper concentric rings. Inside diameter, inches................ Sesh aR a Ne ar ence tear rae LEY RRR Eat 54 8% _ Each......... eae oe Bet leavers) ROO e Mane on Se Ae Ae es Duo nS 5.35 8.30 9869. ditto, but with tripod. The small size includes No. 9736 Tripod, 6% inches inside diameter; while the large size includes No. 9737 Tripod. Inside: diameter: inches 0.4.16.) oh t gwen bane ib janhaleos Games my etn gwen sa 53 8% Bea CH es ee eae aot PA NS ets raced ony Ope Dene Ph ee et ee Dar ab EUS ottins hd NCH valor 6.05 9.30 9870. Water Baths, of polished copper, tin lined; with cover, steam escape, copper concentric rings and perforated plate for test tubes. Without tripod. Diameter inches su cuek eats cicnean ce ween Aaa ee Ran ay Deucb ih 8 Saen pele 5 6 8 Number of rings.................----- SA ES Nei Ae teh ROA ale eA 4 5 7 Diameter of perforations in plate, mm.... fo RR Netra a 2 17 22 Fits Tripod No. 9736 inside diameter, inches...............-.....5--- 5 a 82 ““ Water Bath Support No. 9744, inside diameter, inches............ 6 8 Each........ Rape a Ecaecn oR a ahr oe, BTEC Wi ciel Nts ede a aenentaerie Rene aurea “4.00 4.40 ~—*72.20 10% discount in lots of 12. 9871. ditto, but with Tripod No. 9736. Diameter of water bath, inches.............. 0.0 eee e eee eee eee ant BCI et re ad nea ete een een eae 4.55 5.00 8.00 10% discount in lots of 12. 9872. 9873. 9874. 9875. 9876. 9878. 9879. 9880. 9875 9880 Water Bath, Inactivating, 8 inches diameter by 4 inches high, of heavy copper, tin lined, with flange, tubulations for thermometer and thermo-regulator; removable Tray No. 9489 with eighteen openings 3-inch diameter for test tubes, and set of concentric rings to be used in opening when tray is not used, and with enclosed sheet iron base No. 9744. This water bath alse fits Tripod No. aioe 81 inches. It is also listed with complete equipment for Wassermann work under No. Fe oo ar a oe aes Na ee me ee aah DORAN bin ener clieaced Ririgt hares cee ei Siig and el aah wen ahal ge anre 18.00 Water Bath, Blair, with test tube rack; of polished copper, 175 mm diameter, as used in iron analysis. 5.20 Water Bath, Hofmann, of heavy polished copper. Diameter at top 8 inches, height 5 inches. With a set of concentric rings and plate with five holes of different sizes, each with cover, and with constant water level and handles. Fits No. 9736 Tripod, 63 inches inside diameter. Without tripod.. 17.60 ditto, but with No. 9736 Tripod, 63 inches inside diameter ......................0 00.0 e eee 18.20 Water Level Regulator, of brass; can be attached to any of our water baths. The level of the water is regulated by adjusting the center brass tube. Length, 33 inches........................ 2.00 Water Bath, of copper, cylindrical with offset bottom; 3 inches high by 73 inches diameter, for eighteen test tubes. With tubulation for thermometer, and side tubulation for filling. Perforations in top 20 mm diameter, perforations in removable bottom 12 mm diameter. As used in U. S. Army Medical School. Without tripod............ 00... eee 4.50 ditto, but with No. 9736 Tripod, 67 inches inside diameter.............. 00... 0.0.00 see eee 5.30 Water Bath, of polished copper, tin lined, 6 inches diameter, with concentric rings, water level regulator, and safety gauge, with hole in bottom for insertion of burner, for use with inflammable liquids. With tripod; but without: burner... 2:5.05.4.00 gi pe ecune en heu See Ee eed eden 20.00 9887 9890 9881. Water Bath, new form, with water level regulator; of polished copper, 6 inches diameter by 4 inches deep. With sheet metal tripod, 9 inches high. .............0000.00 000 ccc ccc eee eens 8.00 9882. Water Baths, Funnel Form, of copper, with water level, but without tripod. Miameter, NChes races oh ehcc ie atte Nha utr oh f Stauants AN Mudls J in elas et hee AS 6 8 Fits No. 9736 Tripod, size, inches..........0.000 00.000 ccc eee 3 6z Each) without tripod we 3 eye aes ep sled siecaen tsk eae Sem ant ad a wea fe 4.25 6.50 9883. ditto, but with tripod. Diameter of bath, inches............................... 6 8 Bae COMpletez ca. nanos tee ee cs teen ete aes ten ars eA 4.80 7.20 9885. Water Bath, Circular Form, of heavy copper, tin lined, on rigid base; 16 inches diameter by 4 inches deep by 13 inches high, including base. With six openings 3 inches diameter, and one opening 6 inches diameter; each provided with concentric rings and cover; and with stopcock and water level MOGUlaA GOI ari cnn ae eae a crea edna cotta Notts te teh nese te souietes ara, canis be atener emia Acktebe ENE 25.60 9886. Water Bath, for dissolving steel samples; of heavy polished copper, tinned inside, with test-tube rack 6 inches diameter by 7 inches high, taking eighteen test tubes 150 x18 mm.............. 5.20 9887. Water Bath, Rectangular, for dissolving steel samples; of heavy polished copper, 74 inches square by 64 inches deep; with perforated tray to hold twenty-five test tubes 175 x 20 mm. On support WICH ATOM LOGS i secieeerse se initus aM eyes maecee'y Donen alert a et ello, Veet Ay teh ee ma worn os Oe Dn eg 13.75 9888. Water Bath Rack, for test tubes, of polished copper, with handle, made to fit Water Baths Nos. 9870 and 9880. For Bath, diameter, inches..................... 000.0... 6 8 Diameter’of inset; inches:.../.6 jes dened beh EEE PG ER ee ie od te 52 7 Number of nolesiesces cn tonne tei ae Masta esac ase ie einen ing Seiad 16 28 Diameter: of holes; inchésics i. ss8 avn eae aesn oon ven ene a eg RR ee ee Bea oli cts eet yen tree ted esse em aes fiomecy aes eta ce eevname nae hte Me nee VERO Ya 4.80 4.80 9890. Water Bath, Whipple, Electric, of copper, tin lined; designed for melting gelatine in culture tubes. The water is kept heated to about the correct temperature for melting gelatine by means of an incandescent lamp supplied with the bath. Dimensions, 12 inches diameter by 5 inches deep; with rack to accommodate forty-eight tubes ?-inch diameter. For 110 volts.............. 21.85 611 9892. 9893. 9894. 9895. 9896. 9897. 9898. 9892 A i! Lid 9896 Water Bath, Dr. S. W. Wiley, Patented, Standard Size, of heavy copper, for economizing time and gas; with twelve holes 34 inches diameter and two holes 53 inches diameter. The top of the bath is 14 x 253 inches. The cup is of heavy spun copper and easily replaced when burnt out. With concentric copper rings and extra copper cup, but without porcelain rings................ 70.00 Spun Copper Cup, only, for use with above Water Bath................. 0.0.0.0. c cece eee 1.60 Water Bath, Dr. S. W. Wiley, Patented, Small Size, exactly similar to No. 9892, except that top dimensions are 14 x 123 inches; with two holes 53 inches diameter and three holes 34 inches diameter, all fitted with concentric copper rings. With extra copper cup............... 0.0002 e eee eee 55.00 Water Bath, Dr. S. W. Wiley, Patented, “‘Midget,’’ of same construction and operating on same principle as the Standard Wiley Water Bath, but of circular form with top diameter 12 inches; with one hole 34 inches diameter, and six holes 24 inches diameter, each fitted with concentric copper rings. This bath has been widely used for milk analysis 26. Water Bath, of copper, tin lined, 23 inches by 133 inches by 5 inches; with stopcock to draw off the water, Kekule water level regulator, extra sheet-iron bottom and detachable legs. With seven openings, three 6-inch diameter and four 4-inch diameter, each provided with concentric rings and COMER ae re eed orci ser es ee tag Sli Maa Na a inl. cht pee fy rl nahn Mladen eauly ea uaa Seeds eS Heat a aN a fa 32.00 ditto; but fitted with:steam: ‘coil for Heating. « :c.43....2¢8 ses ee ba ee dags SASS Ree poe odes 40.00 Water Bath, exactly same as No. 9896, but fitted with resistance for electric heating and three-heat plug type switch. On 110-volt circuit consumes 500 watts on low, 825 watts on medium, and 1750 watts on high heat. Requires 20 to 30 minutes to reach boiling point. Because of wattage required, cannot be used on ordinary lamp socket, and must be attached to line of at least 15 amperes. Coils must be covered with water at all times to prevent burning out. For 110 volts.......... 96.00 9900. Water Bath, of copper, tin lined, 14 inches by 14 inches by 5 inches; with stopcock to draw off water, Kekule water level regulator, extra sheet- iron bottom and detachable legs. With four openings 5 inches diameter, each provided with concentric rings and cover............... 22.40 9901. ditto, but fitted with steam coil for heating... 29.60 9902. Water Bath, exactly same as No. 9900, but fitted with resistance for electric heating and three heat plug type switch. On 110-volt circuit consumes 500 watts on low, 825 watts on medium, and 1750 watts on high heat. Requires 20 to 30 minutes to reach boiling point. Coils must be covered with water at all times to prevent burning out. Be- cause of wattage required, cannot be used on or- dinary lamp socket, and must be attached to line of at least 15 amperes. For 110 volts.... 72.00 ld 612 9908. Water Bath, of copper, tin lined, 28 inches by 14 inches by 5 inches; with stopcock to draw off water, Kekule water level regulator, extra sheet-iron bottom and detachable legs. With eight openings 5 inches diameter, each provided with concentric rings and cover.......................- 35.20 9909. ditto, but fitted with steam coil for heating.................0000000 00000 cee eee 48.00 9910. Water Bath, exactly same as No. 9908, but fitted with resistance for electric heating and three-heat plug type switch. On 110-volt circuit consumes 500 watts on low, 825 watts on medium, and 1750 watts on high heat. Requires 20 to 30 minutes to reach boiling point. Coils must be covered with water at all times to prevent burning out. Because of wattage required, cannot be used on ordinary lamp socket, and must be attached to line of at least 15 amperes. For 110 volts......... 102.40 ji i | oo ii i tl oh =m | : ? | H 9912 9912. Water Bath, Rectangular Form, of copper, tin lined, with two removable covers, one provided with two 5-inch openings fitted with concentric rings and cover; and the other with thirty-six j-inch holes for test tubes, etc. Dimensions 144 x 6} x 3 inches deep; 7} inches high, including base, in which is fixed a special set of gas burners in a double row for rapid heating..... omer are ei 2+ 32.00 9913. ditto, but with resistancé for electric heating, and provided with automatic cut-out which cuts off current if the bath is allowed to run dry. With cord and lamp socket plug. For 110-volt CIRCUI Gs sii ao oii cnee nore 2 aay eer SF oe dearer eter Lhe wie ts ak ented Sulla Pek MA Beat Ne pe aon errs 48.00 i) | TY 9914 9915 9914. | Water Bath, Electric, of heavy polished copper, tin lined, mounted on short brass legs. Outside dimensions 15 x 8x 5 inches. With removable perforated tray and cover containing two openings 63 inches diameter, each fitted with concentric rings that will accommodate seven different sizes of dishes. The bath holds approximately 2} gallons, and takes about one hour to heat water from 18° C to boiling. Equipped with a 9-ampere heater with three-heat control switch. Medium heat draws 41 amperes, low heat 2} amperes on 110-volt circuit... .........-0 0.0. eee 50.00 9915. ditto, but 15 x 15 x 5 inches, with four openings in cover. The bath holds approximately 43 gallons, and takes about one hour to heat the water from 18° C to boiling point. Equipped with a 12-ampere heater with three-heat control switch. Medium heat draws 6 amperes, and low heat 3 amperes on 110-volt Circuit. . 0.0.0... c eee een nent e en nee n teen es 80.00 9922. 9923. 9924. Water Bath, DeKhotinsky, Electric, of nickel-plated copper, insulated with 1 inch of magnesia asbestos and protected on the outside by a fibre covering. Mounted on an iron base, and fitted with a supporting rod for flasks, condensers, etc., as shown in the illustration. A set of six concentric porcelain rings is mounted in the cover. The outside diameter of the bath is 190 mm, and the inside 140 mm. The heating is done with four units wound for 44 watts each. With one unit in circuit, water is maintained at a temperature of 72° C; with two units at 95° C; with three units at 100° C; and with four units at 100° C, but with much more rapid boiling. With cord and plug for ordinary lamp socket, but without the glassware shown in illustration. For 110 volts... 35.00 Heating Units, for above water bath. Four sections are required for a complete renewal. Per section, WOUNG LOE TUOMVOltS .c7 ah ook treet is hareanay horas Aer aE oe ae Renee ... 1.00 NING SS ! | SS i aw a ee DLs eo ais = 5 a J ¢ ! 9924 Water Bath, Freas Electric, consisting of a copper tank with inside working space of 18 x 12 x 4 inches. With removable cover provided with six openings, each fitted with a set of concentric rings. The copper bath is mounted in a box made of two layers of asbestos transite with a space of 33 inches between, which is filled with asbestos air-cell insulation. The wire-wound removable resistance plate is the same size as the bottom of the tank and serves as a heating unit. The Freas Regulator controls the temperature of the bath from room temperature to boiling point, with a regulation of 1 to 5°. When connected with ordinary 110-volt lamp socket, the temperature of the water in the bath reaches 65° C, but heating plate is wound for 1500 watts and must be connected directly to 15-ampere line for boiling. For 110-volt circuit... .............00. 0000 c eee ee 180.00 614 A R T H U_R H. TH OQ MA: 3s Cc :-O M PP A N ¥ | 9926 WATER BATH, ELECTRIC, DeKhotinsky, for constant temperatures, consisting of a copper container ¢'mm thick, heavily nickel plated inside and out, lagged with 25-mm magnesia asbestos, and protected outside by a sheet of Russia iron. The bath is attached to an enameled cast-iron base, supplied with three nickel-plated rods, to which may be attached laboratory clamps for supporting flasks, ete. Each bath is fitted with four electric heating units, three of which may conveniently be added one by one, by means of the switch constituting part of the bath. The fourth unit is electrically connected to the relay, which is automatically operated by a thermo- regulator. OY The thermo-regulator consists of a solid drawn steel tube, brass covered, nickel plated, filled with mercury, with a platinum contact attached to a regulating cap, by means of which the bath can be regulated and set to the desired temperature, ranging from the temperature of the surrounding atmosphere to the boiling point of water. Should a temperature higher than the boiling point be needed, the water may be replaced by ‘‘Crisco,” which can be used up to a temperature of 165° C, or even higher. For temperatures within 2° of room temperature and lower, the cooling cell must be used. A constant water level attachment is furnished with each bath, by means of which the water level can be regulated within a range of 35 mm, and maintained within 1 mm of the level at which it is set. This bath has a very good natural circulation, as heat is supplied inside the bath 25 mm from the bottom. When experiments or research demand a more vigorous circulation and regulation closer than 75° C, a small high-speed Turbine Type Stirrer No. 9240 can be attached to the bath. This stirrer of 18-mm diameter takes water from the bottom of the bath at the rate of 5 liters per minute, and delivers it at the top with an energy expenditure in the motor of 15 watts. On the shaft of the circulation turbine is an extra pulley to connect with the glass stirrer in the flask. 9926. Water Bath, DeKhotinsky Electric, as described above; without cooling cell, and high speed turbine stirrer, but with thermo-regulator, constant water level, 5 ft. of cord and plug, and relay for TOS OLE Ce, ta aus seosertel toa eagn secre torce Remar s ORS Bm stile aces notary cdytnccen eK bors Masi oh ny Sion lpel oe 97.50 9927. ditto, but for 110-volt, 60-cycle, a.c................ emer ae marian tetera. -oo........ 100.00 9928. Cooling Cell, only, of copper, nickel plated, for use in DeKhotinsky Water Baths.............. 12.00 Water Bath, Sargent Electric, for maintaining a constant temperature at any point between 30° and 100° C, with a variation of from 1° to 2° under proper conditions. There are four openings 5 inches diameter, each with copper concentric rings and a support with four clamps. This bath is designed for use in digestions, as in fertilizer work, and for distillation of inflammable volatile materials, and similar work. It is intended to accommodate flasks and dishes only, and is not suitable for use with beakers, test tubes, or other vessels requiring deep immersion. Dimensions, 13 x 13 x 9 inches high. Construction is of copper and asbestos with brass trimmings. Without thermometer or glassware, but with cord and plug for 110-volt circuit. ... 0.6.0.2... eee ee 85.00 9931. ditto, but for 220-volt circuit... 0.62.6. - 6 eee ees en 85.00 9930. TT : i F | | : ! Ls 4010 4014 CONSTANT TEMPERATURE BATH as developed in the experimental laboratories of the Leeds & North- rup Company, is a simple type of bath without automatic regulation, intended for use with a Beckmann thermometer reading to 0.01°C. This bath consists of a glass jar enclosed in a polished metallic jacket which provides an air insulting space around the jar. The removable lid is insulated with cork and carries the thermom- eter holder, adjustable support for the incandescent lamp and stirring device. A holder A for two test tubes is also provided. These tubes are partially filled with mercury and in them are placed the amalgamated ends of the lead wires for connecting to the bridge through the binding posts B. Two insulated connectors run from these tubes to the mercury tubes of the conductivity cell. This method of making connections is convenient and re- duces the passage of heat between the cell and the room since both ends of the connecting wires are at the temp- erature of the bath. Support for the conductivity cell C is suspended across the top of the jar and the cell is held in place by spring clips. The stirring device is provided with pulley for belt drive, as this method keeps the motor away from the bath vapor and permits regulation of speed by means of cone pulleys. 4010. Constant Temperature Bath, as above described, consisting of a glass jar 83 by 122 inches, with a capacity of about 33 gallons, polished metallic jacket, insulated wooden top with binding post connectors, hangers and tubes for mercury contact, support for electrolytic cell, stirring device, and heating lamp for 110 volts, with cordjand plug, but not including Beckmann thermometer, electrolytic cell or regulating rh eosta tac nets ere ie saute wre caees bocce nt rat paren eae aed a peeooe oa eas yl co RA Ae aly lg 100.00 CONSTANT TEMPERATURE BATH, Freas Automatic. This is sometimes referred to as the ‘‘Small Sen- sitive Freas Thermostat.” It consists of a glass tank, covered on the outside with horse-hair felt to a thickness of about one inch and on the outside of this felt insulation is placed a cover of linoleum. A portion of this tank con- sisting of a strip about three inches wide extending from top to bottom is not covered with insulation and serves as awindow through which the operator can observe his work. Regulation is by means of the Freas mercury thermo-regulator consisting of a Pyrex glass regulator tube filled with mercury working through a thermal relay. Heating is by means of two electric lamps. The stirring device is operated by an electric motor suspended by means of two springs as shown in illustration. This stirring device keeps the water in the tank in constant and thorough agitation. The regulator is sensitive to a range of 0.01°C, but in practical work under fair conditions a regulation within + 0.02°C over a period of five minutes and within 0.05°C for periods of an hour or longer is easily attained. 4014. Constant Temperature Bath, Freas Automatic, as above described, consisting of a glass tank 15-inch diameter by 14-inch depth, ten gallons capacity with Freas mercury thermo-regulator with thermal relay, heating lamps, stirring device, and electric motor for 110-volt, 60-cycle, a.c. With ther- mometer’ 0: to;70?"@an. 1 divisionsec 6s. co tics: isk eh nls a aden nly Rlyen cad ee Wate ee eS 220.00 4015. ditto, but with:motor for 110 Vvoltidic@h. oe. ca oes gs cee kwh a eres hPa Soc ud ame ees SR eS 220.00 4016. Glass Tank, only, for Freas Automatic Constant Temperature Bath, 15 inches diameter by 15 inches GOOD it cole) cts fede shu eens, ws abd all greabere arate aye ake eupthbaecalan slr wie ae Suse is chars aranua gus at meatal roads 13.90 Water Baths, Wassermann, See Serological Section, page 40, 41, 42 and 43. Water Blast, see Filter Pumps with reservoir, page 282. 616 SOP ml | ™ 500) 4459 409 —|350 —} 300 74159 aay | + nes | ig cc 9954 9961— (3 actual size) : WATER EXAMINATION APPARATUS, Whipple, for the Microscopic Examination of Water, as described in “The Microscopy of Drinking Water,’ by Geo. C. Whipple; consisting of the following : 9940. Sedgewick- Rafter Funnel, graduated, with attachment and rubber BuOEBERS Pe Cree San Enea eens AO) 9941. o> TSUN eTaAGuated es) 6. ea RS AS ah a eee enenenr ntrana acaee ARTS Berkshire: Sand. P Ot ND ss cs ok ces ty eh ines ee Ee I es Sn se 16 9942. ‘Bolting:Cloth Discs; per doOZeIs + «vee ws dome nner na oAeae a Ay ade Wane eles ea oun be GALaues = 15 9943. Ceunting Cell......... ba Bas ae take see belatiay als Wha etgalvnhei eae ado BE mae gran eicer a hace 5.50 -10 9944. Cover Slip......... Ppt Beale ie Se a ete oe ea ere eee emake NSE - 6842. Ocular Micrometer Dise, Whipple, for counting bacteria, consisting of a large square divided into 100 small squares, one of which is sub-divided into 25 squares.........................0... 6.25 8150. Pipettes, Transfer, capacity, ml............00 000... 1 5 BS OVE ig se deseo SEAR LOT Ne bas oA I FEA ed Ae Oe ed CR aE EE eG Wine oe Rees -18 18 5461. ‘Flask, Volumetric, with ground-glass stopper, graduated to contain. Capacity 25ml.............. -85 9950. Water Heater, Fletcher, with attachment for instantaneously heating water. When connected with cold water faucet hot water is delivered in three seconds after gas is lighted. Gas supply of 3-inch 10 clear bore is recommended. Complete with burner as illustrated........................ 25 9954. Water Sampling Apparatus, Esmarch, consisting of a glass bottle in a metal frame with parts so arranged that when the apparatus is lowered to the desired con the stopper is removed, whereupon the bottle fills, after which the stopper is replaced.......... 0.0.22. 12.00 Wax, Sealing, red, first quality, in sticks. Berita eee Oe Ta oi ent ties erence en beget 1.85 9960. Weighing Bottles, high form, with flat bottom and Bee aiidselis stopper. 60 60 80 ©6100 100 120 Height mmc vog ges ecidoresanu pats Cua oe 10 15 15 23 25 32 Diameter, mm. Crean AR) ae Hen es es tera hk ees Ce ee PE A echonea al Men, .20 .20 25 .40 .40 50 10% discount in carton containing 12. 9961. ditto, but with round bottom. Height. TYLT Tees eee sme eee ee een TaA MM een petits 60 80 100 120 Diameter, mm. 5 : Rhee Maas Owe inte . 10 15 238 82 Each Saad ene os yeetiih SUB roa Sees Rem carey Grek ade eR eUa ee gs -20 -25 35 45 10% discount in carton containing 12. A. RR. T HH UR H. T H O M A'S Cc O M P A N_ Y 50x38 | mm sn TS2.,. wll ART eo 9965—(4 actual size) 9980 AH.T.CO. 5 A.W.T.CU, Ve 9974 9967 9968 9970 9972 9982, 9983, 9984 9964. Weighing Bottles, wide form with flat bottom and ground-glass stopper. CLONE MIMI res ee. eer nce cept ee 40 50 50 50 50 60 70 80 Diameter,mm......... pfoieed eae sey is 25 25 30 38 40 30 35 45 Hah seen rere ees yiat eta mee .25 30 ~—-.30 40 = .50 -40 .40 -60 10% discount in carton containing a 9965. Weighing Bottles, low form, with flat bottom. eI gn be mms + ees cle th ce Weer viee ccutt we tbh gene Oye a ee list RIAA cares Rha Cadet 30 30 30 Diameter, mm Siete wae oat ‘ 50 60 70 aC sos ety esis MMR Re onset eterna at SAS d ate AEDES Sh a tote EN Soret AE 2 ree -85 1.20 1.60 10% discount in carton containing 12. 9966. Weighing Bottle, conical form with flat bottom and eon one GAO AUG YaIT i tk, a oh ie ih neh AA DIS kIT ca Feo EM AEN ty ea LER, 1 ole, Nel 15 30 60 AC Hees ras pce eed es ee ene ee nk Ok Sane a ene wen AS i Aine ty gine aves wee OO ere -40 -50 -60 10% discount in carton containing 12. 9967. ditto but with extra wide mouth and with lower part of stopper sealed over. Capacity, 15 ml..... .40 10% discount in carton containing 12. 9968. Weighing Bottle, Grethen, with ground-in stopper, with glass stopcock. For weighing corrosive liquids. Capacitys 2 Mille pitenie trite castenty eas miei tiene ce Jonnie een ou el amar & xe tentotae emma ahha re aabtee noun tare 2.40 9970. Weighing Bottle, Hill, 30 ml, with ground-in bulb, pipette and glass cap........................ 1.70 9972. Weighing Bottle, Lunge, with Sou stopper with bulb and two glass stopcocks. For weighing corrosive lnquids “Capacity. Orme. Aes Ser oe eh oct ARNON, laa gas Sita) Sane nie ea on eee eee ene 4.00 9974. Weighing Bottle Support, with countenpoise, ae aietal eae bottles such as No. 9961. Can be used either vertically or horizontally . CPenathe the Nena hte Oe aetna Rae ees OO) 9980. Wire, Aluminum. B.&S. Gauge...... es Aeoree 12 16 18 20 22 24 Per foot, in coils of 24 inches....................... .. 10 12 14 15 18 .28 9982. Wire, Soft Brass, wound on spools of } lb. elk B. & S. Gauge........ 16 18 20 22 24 26 28 30 32 34 36 Per spool............ woe .23 .25 .26 .28 .30 35 -45 55 -60 85 9983. Wire, Copper, bare, wound on spools of } lb. each. B. & S. Gauge........ 16 18 20 22 24 26 28 3 32 34 36 Per spool............ -23 25 27 .30 .30 .30 37 -46 50 55 1.20 9984. Wire, German Silver, wound on spools of } lb. each. BiG Ss CAUsee Beet teencne tes hedes : 16 18 20 22: 24 26 28 30 Per :Spoolis cain hepsi Oe ayeR tee Aes AW 50 -50 -50 -60 -60 -65 -80 1.00 61 9992, 9993, 9994 Wire, Iron, No. 30 gauge; chemically pure for standardizing, containing 99.85% Fe. PGB 2 eatin he eee teen oR SSIS en AE Ae tie Reta eae nr 8 Sa ame hectares etn ar seen .22 s 4 DUDE ED EEE Dn en net ete terete tere etter eens 45 Bae dar oy Ape whe poeta (5 into) ye 2 maremeattyn Matin Sarin Poca ish OL cate We pment ula seen Resa Ae ae Se mse -70 9986. Wire, Pure Nickel, B. & S. gauge........................0.... 16 18 20 22 24 26 PCR OZ seh eae ee Ot tenet Eee Mean eae oe 20 20 .20 20 20 20 7435. Wire, Chromel. A nickel chromium alloy which resists destructive oxidation to a remarkable degree, even at high temperatures, and which is non-corrosive at normal temperatures. The only satis- factory substitute for platinum wire for bacteriological inoculating needles. In coils 24 inches long. B. & S. gauge...... TPN SEN PE aust a Te ee Strate Lana Seed 22 24 26 28 Pre 24 IN CHZCOUN oa 3 een A eR ee ene Oy at een ge 10 10 10 -10 9988. Wire Gauze, Brass, 20 mesh. This mesh is made of No. 26 wire, 20 mesh to the inch, being a suitable thickness and mesh for heating beakers, dishes, etc. This gauze is stocked in rolls 24 inches wide and is sold in any length cut across the roll, i. e., one dimension ordered must be 24 inches, to avoid waste in cutting. Per square foot.............. 0... -60 9989. ditto, but of iron wire. Per square foot... 2.00... 0 0. cc cece beeen eee eee b ee eens tees .30 9990. ditto, but of copper wire. Per square foot... 0.0.00... cee eee -60 9992. Wire Gauze Squares, Brass, same mesh as No. 9988, for heating beakers, dishes, etc., over flame. Cie TNC OSs wuecetesuox S.cias Cine iets neater pan nos Fa ole ny tn uene laren 4 5 6 Per-square:: 4nd see er ees ere fess be apeerageeen Bas Geetcremtr ay ia meee! 10 15 = .20 10°% discount in lots of 12. 20° discount in lots of 144. 9993. ditto, but of Chromel wire; of great durability because of the high heat-resisting quality of this alloy. Made of No. 24 wire, 16 mesh to the inch. GigE MT CHES cos rne a eth selene amy ha Da rae ae Been ae Meiners aaa 4 5 6 Per squares icc g.n ace otek eee aes aes enh aah ee oe arate 45 .65 -95 9994. ditto, but of 20-mesh iron wire, for heating beakers, dishes, etc., over flame. SiO INCHES creeds see Saemieainn e Ra te tanh eed are a ae EDN ares Ah hates 5 6 8 Per SQUATE? sco. gps etiniee RES RE Bo oe Gee Mid eh ee ae oS 10 -10 ae 15 10% discount in lots of 12. 20% discount in lots of 144. 9995. Wire Gauze Squares. With asbestos center; of tinned iron wire. Sipe. TCHS. fica Haare ca aR eat a SEG I EE Pet ee ER 4 5 6 Per square.......----0 22s sete essere Sk atta cies Stee Geese Sheahan ea se -10 12 .20 10% discount in lots of 12. 20% discount in lots of 144. 9996. Wire, copper, No. 18 Annunciator; a convenient covered wire for general laboratory use. a »€ , 25 Pee Ub ellanc salesu nares unmetee ns nd rte Vas ones oe hatineieae tani Sa eae PGE EU ecules eects ee rare a ne Ie EN Ra erree eye eave 75 ire, si bber insulated, for connection of electrical measuring instruments in laboratory use. This Sere ae a Sale conductor silk fixture cord with heavy rubber insulation, of about the carrying capacity of No. 18 wire; particularly recommended for use with potentiometers, measuring bridges and other precise electrical measuring ar a : rt 10 ft......... ree eee 50 : Re ‘ont lengths for connection of electrical measuring instruments, with nickel plate re SE set tral nto hard rubber handle, soldered to both ends. 2 U-shaped terminals screwed i Lengths of, feet......------ 1 2 3 4 6 12 .85 -90 95 1.00 1.10 1.40 A|. Founpzp 1899 CODE INDEX AND CONDENSED PRICE LIST APPLYING TO 1921 GENERAL CATALOGUE a code word for each size of every item in our catalogue, with the exception of Reagents, which are coded in the listing. The use of this index in the preparation of order lists will be found convenient and time saving by those familiar with our stock because of the brief description of apparatus: and prices which have been included. Separate printing of this Code Index and Condensed Price List provides a method for publica-. tion of important price changes between the editions of the catalogue and it is our intention to republish it as often as may be necessary during the life of this edition of our catalogue. [: this Code Index and Condensed Price List will be found Our code words all consist of five letters and as ten letters are permitted by regulations for both inland and trans-oceanic dispatches, two of our words can always be combined into one word in the message without possibility of confusion in decod- ing, as in this operation our first step is to divide all ten letter — words into two component words of five letters each. In trans- oceanic cabling, our code words for the items can be freely used with the words from any of the codes in general use, thus greatly shortening the message. We send telegraphic acknowledgment where it seems desirable, but we suggest that such acknowledgment be specifically requested where it is considered to be absolutely necessary. All prices subject to change without notice CaBLE ADDRESS, “BALANCE,” PHILADELPHIA Copzs: A. B. C., 5rH AND 6TH Ep., Marconi, AND BENTLEY IMPROVED ARTHUR H. THOMAS COMPANY WEST WASHINGTON SQUARE PHILADELPHIA U.S. A. INCORPORATED, STATE OF PENNSYLVANIA, 1900 A R T H U R H. a H O M A 8 Cc O M P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 1000 Apsorpt ION BLOCK _.14x25 mm box $1.60 Abact 1082 Anaerobic Culture Apparatus, Novy........ ea. $7.25 Acyjf 1004 = Acid basins... 22... 115 mm ea. 55 Abasm 1083 do., but without clamps................ 7 6.00 Acyxc 130 mm “ 15 Abawe 1084 Iron clamps only.....................05- pair 1.50 Aczyz 160mm “ 1.05 Abazy 1086 Anaerobic culture apparatus, Smillie. ...... ea. 11.35 Adalz 1005 “pitcher, porcelain... . ‘ fe 50 ml“ 2.65 Abbyz 1087 Stopcock tube only, for No. 1086.......... o 3.00 Adazu 2:00ml “ 3.95 Abcif 1088 Perforated glass bulb“ “ “........... . 1.60 Aderi 1006 “ “stone 2000 ml“ 50 Abduf 1092. Anemometer (Air meter)................. “48.75 Addpl 4000 ml“ 85 Abebr 1093 Biram pattern............... “47.50 Adehb 8000 ml“ 1.30 Abeel ; : 1007 “pump... Sie ean! 8.35 Abeqm 1099 ANIMAL BALANCE, Decimal, without / 1008 Adapters, curved........ 150mm “ 29 Abfia weights. ............... ‘ 20.00 Adeys 180 mm “ 35 Abfsh 1100 Fy a Troemner, with 200 mm “ AS Abgar weights......... “81.90 Adgan 1009 “ straight............... 150mm “ 25 Abhms 1102 . Board, wood with hooks 12x8in. ‘ 3.20 Adhmo 180mm “ 35 Abkub “ «95x12 in. “6.40 Adifb 200 mm “ ‘45 Abibn 1104 a OE TWaata ples en sayas eo rcssnt « “50.00 Adisa 1106 o Cages: puneveeas 12x16x12in. “ 27.50 Adjfa 1012 AIR PUMP, HE fans dare wtretonn eats waits 18.35 Abise 18x24xl6in. “ 38.50 Adkit 1015 vacuum and pressure . o 16.00 Adbjiy 1108 = SEVGUM 32235 dae 20x12x12in. “ 22.00 Adlut 1018 o “mercury vapor, Pyrex glass... Doe 40.00 Abkyg 1110 ff ts .20x16x8 in.“ 22.00 Adney 1020 ns HE AGerylges ets sin oe Oe ani 5 75.00 Abmuw | 1112 : Phipps model. 14x14x16 in. “ 7.50 Adoex 1022 s “Langmuir......... 110 volts“ 120.00 Abofz 1113 oS “ Supportsfor No.1112...... of 1.75 Adosu 1023 e “_ G. E. two stage... 0.0.2... “368.00 Abosy 1114 > ‘ Vaughan.....12x20x15in. “ 13.20 Adpob 1024 ff SE S@Ubfte Geese ees 10d.c. “ 570.50 Abpyl 1116 oe Holder, for mice.............-. i 5.00 Adrim 1025 a “ CE AvA Gah a 110a.c. “ 585.00 Abrur 1118 a BE MOBO b attains os 7x2Yg in.“ 2.20 Adssq 1028 a Cenco Hyvac without base or i & vie ee aebe tated 8x3l4 in. “ 2.50 Adswi TMOLOR Regen tence eee 50.00 Absis 1120 is Head holder...............2.-- 3 10.00 Adtin 1029 2 “~~ CenecoHyvac on base 1122 i Varies is. ce noc ae 5x6in. “ 3.00 Adukf with motor.... 110d.c¢. “ 89.00 Adtir 8x81g in. “ 4.25 Aduny 1030 _ “ditto, but.......... HOac “ 90.00 Abumf 10%xllin. “ 8.00 Adugs 1032 os Ss & blower, Cenco Ro- 15xl6in. “ 24.75 Adutm tary,small,motor 110d.c. “ 47.00 Abvac 1127 vs Table, Brodie, lamps for 110 v... “ 120.00 Advuj ditto, large........ 110d.c¢. “ 61.00 Abvim 1128 a Tags, aluminum, numbered..... 100 = 3.25 Adzhi 1033 ff “ eS) esta. nase 1l0a.c. “ 50.00 Abwum | 1140 Annealing Cups, No.0........ Vy exl gi in. doz. 2.55 Adydp VBP G6 coe asi: 110a.c. “ 67.00 Ababy HUN OD vse. 14 xllgin. “ 2.55 Adyif 1034 is eg “without base No. 2.. U4xlin. “ 2.55 Adymz or motor..... small ‘“ 15.00 Abydt 1141 A “Covers, NOs Of oe ike oe 15 Adzdo large “‘ 20.00 Abygn NOs tledicey seveaeton os 15 Adzie 1036 “Crowell No. 1-A Rotary with- NOADiwe Zan sani oe 15 Adznt out air receiver or motor.... “ 28.00 Abyso TTSOS PAV etn eect acesy tae 176x15x3 in. ea 1.25 Aeaib ditto, but No. 2-A. Ee 36.00 Adbyur 1152 oS SSQUARO A iek Soe dyisccnesirsn an Sah oe tin: “ 70 Acawy 1038 i. - Crowell O- D, without oil box... “ 55.00 Abzsn 14in. “ 90 Aeder 1040 o “ditto, with oil box. Bee 66.00 Acamz Zane. 1.25 Aebjy 1042 ih “Crowell 1-D, without air re- 1154 “with vise, jaw width......... llgin. “ 2.50 Aechb ceiver or motor............ eS 78.00 Acbem Jin. 3.55 Aecno AittO, bUb2-D iis eoceiog osine ones a 95.00 Acbor gin. “ 4.85 Aecse aes 1D ee een eres “220.00 Accat 1160 Aprons, rubber cloth............ 25x36 in.“ 1.00 Aedls 1044 a “Crowell 1-D, with motor for 36x46in. “ 2.00 Aeduz WOd.e................... © 304.75 Accry 1162 Oversleeves, rubber cloth................. pr. 60 Aceok ditto, but 2-D.......2....... “366.40 Acdek 1170 = Aquaria, oblong, glass. . 1014x614x1014 in. ea. 5.00 Aefju 1045 es “Crowell I-D, with motor for 13x8x13in. “ 11.00 Aefoj 110 or 220 a. c. 60cye.3phase “ 296.00 Aceib 1172 “Plate glass.......... 18x10xllin. “ 15.00 Aegsa ditto, but2-D.............. “328.00 Acelv 20x12x12in. “ 16.50 Aeguu 1050 = Air receiver for Pump 1-A........ No.1 “ = 12.00 Acfbo 22x14x13in. “ = 19.00 Aehak IeDeseger a 12.00 Acfon 1174 “round; high: cas. 4080s 5x6in. “ 1.45 Aehuv Dae cases Nod 12.00 Acgap 6x7in. “ 1.95 Aehzl 2-19) 2. es 12.00 Acgom 8x8l4in. “ 3.15 Aeifz 1052. Airpumpplate............. diameter 25 em “ 17.50 Achrf 8x9in. “ 3.50 Aeijr 1054. Vacuum gauge, MacLeod................. “ 60.00 Acijv 1014xllin. “ 5.75 Aeini 1056 Air sampling apparatus, Palmer............ 200.00 Acizs : 15xl6in. “ 17.50 Aeira 1061 Alkalimeter, Schroedter, without tube... ... fe 3.50 Ackiv 1176 = Aquaria, round, low............. 4lex7in. “ 1.75 Aejko 1062 i with tube. . S 5.00 Aciak 5x8in. “ 2.25 Aejrz 1063 ae GeisSlbES. Juana Saat 22 i 7.00 Acnai 614x1l0in. “ 2.15 Aekah 1064 ef “e ew form e 7.00 Acoir 74xl2in. “ 3.50 Aekir 1065 " TKN OR Sinica Pte heeds oeekene a = 12.00 Acowo 8loxl4in. “ 5.25 Aekry 914xl6in. “ 7.40 Aekwo 1070 AMPOULES, sealed neck........ — Iml 100 1.50 Acgip 1014x18in. “ 10.80 Aekzi 2ml “ 1.50 Acgpa 1178 Arsenic apparatus, Gutzeit................ a 10.00 Aeinf 5ml “ 2.50 Acquvo 1180 FO Ae eect nels ages 15 Aemex 10m] “ 4.35 Acrew 1182 = Arsenic tubes, Pyrex............ Form A “ 10 Aemis 25ml) 8.10 Acrst FormB “ 10 Aemzk 1071 " openneck......... lm “ 1.50 Acsyg 1184 a i “with constriction. ..... sf 90 Aenli 2m) “ 1.50 Actba 1186 ‘i - LUCA eae t yak eee decee wickets 1.20 Aeoad Sm.“ 2.50 Actho 1188 Asbestos Board, 42x48 in., Thick. gyin. |b. 20 Aeoru 10ml “ 4.35 Actlg ysin. “ 20 Aeoxi 25 ml 8.10 Actun wif. “ .20 Aepac 1076 Anaerobic Culture Apparatus, Buchner..... ea. 18 Acukh Jein. “ 20 Aepeu 1078 McLeod. . 3.50 Acuxg in. “ 20 Aepki 1079 Porcelain Capsule only for No. 1078... s 1.50 Acwij Yin. “ 20 Aepoz 1080 Petri Dish only = . 2.00 Acrsn sein. “ 20 Aepsr A R T H U R H. T H O M A 8 Cc O M P A NY Cat. Code Cat. Code No. Description Size Unit ’ Price Word No. Description Size Unit Price Word 1188 Asbestos Board, 42x48 in., Thick 24in. Ib. $0.20 Aegad 1336 | Evaporating dish, nickel.................. ea. $2.10 Ahfbe 1190 Asbestos board squares............ 4x4in. 10 25 Aewve 1338 Melting pointcup.................0.008. 5.35 Ahfqz 5x5in. “ 30 Aexeg 1340 Slide box, copper, 6 corrugations........... e 5.25 Ahgkl , . : ; ‘6x6in. “ 35 Aexgt 1341 Retort, glass...........00... 250 to 290 ml“ 50 Ahgzg 1192 Asbestos cord, 14° Ib. balls ... .- Fein. ball = 1.00 Aeyda 1342 “Pyrex glass......... Ay pen ee ae oN 1.90 Ahhob yin “ 1.00 Aeygh 1344 Condenser tube................... . AS Ahidax gin, “ 1.00 Aeyjd 1345 Asbestos sheet retort cover ee 50 Ahipy Sein. “ 1.00 Aeym» 1346 Coke bulb, Pyrex glass..................- a 18 Ahjeu 1194 Asbestos Gloves....................000. pr. 6.00 Aeyrk 1348 Tar-acid separatory funnel....... ie 4.50 Ahjol 1196 Asbestos mat, circular............. 854 in. ea. 10 Aezco 1349 ee “ Ag idew ey Mg “ 5.40 Ahkqu 1197 a “ square......... 85x 854 in. “ 30 Aezud 1350 Test tube, Pyrex glass............. eS ~ 40 Ahlgo Hxllin. “ 35 Afaap | 1352 Thermometer, limpid point ‘ 7.50 Ahlul Oxl4in. “ 40 Afadj 1354 Hydrometers, Barrett re guy gam 0.790-0.870 1.50 Ahmij 15xl5in. “ 60 ‘Afahb cE eg a saya 0.860-0.940 “ 1.50 Ahmmb 14x24in. “ 1.00 Afamr i Ben sae he nals 0.930-1.010 “ 1.50 Ahmpu aoaiied 24x30in. “ 2.25 Afapk 1370 Ring and ball melting point apparatus... .. “16.35 Ahneg ig ee ome afe—| 1390. AUTOCLAVE, Chemical 1 pint “© 40.00 Ahntl 1199 Paper, 36 in. wide............... lb. 55 Afelr 1391 Outfit with stand. 1 pint “ 67.90 Ahohj 1200 ASPHALT PENETROMETER, N. Y. 1394 a 25 atm. pressure.. 114 liters “ 100.00 Ahoug Testing Lab’y type............. ea. 110.00 Afdhy 1395 i 60“ “ 3 liters “165.00 Ahpla 1201 —_do., Eut with magnetic clock............ “275.00 Afeed 1398 Wo ateeraeak 1s ae 1500 ml. “ = 275.00 Akg 1 1202 Penetrometer, miniature................. eg 55.00 Afege 5 1203 Needles, Penetrometer................... doz. 6.00 Affde 1400 B ACTERIOLOGICAL INCUBATOR, 1206 Penetrometer, Humboldt................. ea. 85.00 Afgit American standard, low base 1208 Drying oven, N. Y. Test’g Lab’y type...... “45.00 Afhko without equipment. .... 19x12x10in. “ 108.00. Ahraw 1210 Asphalt flow plate and mould............. “10.00 -Afijp 1401 —do., withgasequipment.....19x12x10in. “ 136.35 Ahrni 1212 Asphalt viscosimeter..................... “10.00 Afizm 1402 “electric, 110 volts.......19x12x10in. “ 175.50, Ahrav 1213 Brass plug for No. 1212.................. a 2.25 Afjmi 1404 “ withoutequipment.....20x18x10in. “ 128.25 Ahsqm 1214 Collar, for No. 1212...................0-5 “150 Afksu =| 1405 “ with gasequipment.....20x18x10in. “ 158.25 Ahtic 1218 -Briquette mould for asphalt............... “7.00 Aflup 1406 electric, 110 volts....... 20x18x10 in. “ 195.75 Ahtat 1220 Cubical brass mould............ win. “ 6.00 Afnim 1410 Incubator, American standard, 1222 Bitimen holder, Draper model............ sc 4.65 Afoil high stand, without equip- 1224 Bitumen crucible............ 45x35x24 mm “ 60 Afowi BEG csciace viens # cesesl 18x18x12in. “ 155.25 Ahupm 1226 Ductility machine, Smith, hand power... .. “280.00 Afpox 1411 —do., with gas equipment... .18x18x12in. “ 185.25 Ahvei 1228 Extractor, N. Y. Test'g Lab’y type satis “60.00 Afgye 1412 “electric, 110 volts......18x18x12in. “ 222.75 Ahver 1230 Dulin Rotarex, 110 volt......:.. 1000 grams“ 185.00 Afsro 1414 “ without equipment.....28x18x14in. “ 202.50 Ahwno 1231 BO cert sevens 50 grams“ 95.00 Afila 1415 “ with gas equipment... .28x18xl4in. “ 250.85 Akzao 1320 “hand power...... 100 grams“ = 70.00 Afuen 1416 “ electric, 110 volts...... 28x18xl4in. “ 270.00 Ahzxsd 1233 Plug for Rotarex................0...0.005 «2.25 Afuug 1420 Incubator, American standard, 1234 Filter rings, for No. 1230 Rotarex deereungeces 100 5.50 Afoyx ’ high base, double doors, 1235 bi A NOB a pieaeee . 2.25 Afaky ‘withoutequipment..,..18x30x14in. “ 222.75 Ahyjo 1256 Copper still................ ....Tygx5in, ea. 22.40 Afyid 1421 do., with gas equipment. . . .18x30x14in. “ = 271.00 Ahyyg 1257 Burner, for No. 1256 still................. s 3.20 Afyyu 1422 Ks "electric, 110 volts...... 18x30x14in. “ 290.25 Ahzph 1260 Copper still.........0...0..0... 6x3 in. “ 13.00 Afzyt 1424 “ without equipment. .... 25x30x18in. “ 263.25 Aiact 1264 Burner, for No. 1260 still................. ie 2.40 Agamp | 1425 “ with gas equipment... .25x30x18in. “ 311.50 Acaym 1268 © Connecting tube, glass:................-. re 35 Agboj 1426 “ electric, 110 volts...... 25x30x18in. “ 337.50 Aibrz 1272 Condenser trough, copper, on supports e580 “12.00 Agdde 1430 Shelves, for above incubators. .19x12xl0in. “ 4.40 Aicoe 1276 Condenser tube, glass licen aay 55 : 20 Ageeb. «8 ~, ,20x18x10in. “ 4.80 Aictu 1280 Separatory funnel............... 120ml “ 4.00 Agesy . .18x18x12in. “ 4.80 Aicrm 1284 Hydrometers, Barrett.......... 1.000-1 080 “ 2.80 Agfyl . 28x18xl4in. “ 6.40 Aidag 1.070-1.150 “ 2.80 Agght ..18x30x14in. “ 6.40 Aidey 1286 me Atos Nets canmighe ad 1.150-1.230 “ 2.80 Aghag . .25x30x18 in.“ 6.80 Aidig . 1.230-1.280 “ 2.80 Aghey ©} 1440 Incubator, Hearson, forgas......9x9x12in. “ 85.00 Acdzh 1290 Specific gravity bottle, Barrett... © 50ml “ 1.45 Agibd, 1441 do., FOWOL cisd seca danniee tweens 9x9x12in. “ 85.00 Aiene 1292 . Platinum pan, Barrett test...............- s Agipa 1442 * electric, 110 volts......... 9xOxl2in. “ 95.25 Aifae 1294 Extraction apparatus, Barrett............- i 3.00 Agjew 1444 © FOr Gas: «x ses x eae a 12x12x14in. “ 106.30 Aifst 1295 s Flask for No. 1294............- se 35 Agkuo ‘| 1445 SHOE OL ses ccysaens Seayiates Se J2xl2x14in. “. 106.30 Aigoa 1296 Wire basket for No 1294..............--- a 50 Aglyf 1446 “ electric, 110 volts....... /12x12xl4in. “ 123.00 Aihho 1297 Cover with condenser coil................- ee 2.25 Agngo 1448 AO FORA mre a. wnt ao esate 15x15xi8in. “ 155.00 Aiiab 1300 Schutte penetrometer, with 1 plug big geara 3.15 Agoer 1449 © foroils vues woei s onass 5 15x15x18in. “ 155.00 Atisg 1301 Plug for No. 1300.............:.005- Readies 65 Agorq. 1450 “ electric, 110 volts....... 15x15x18in. “ = 159.50 Aijhm | 1304 »- Distillation thermometer . . "“g-400°C. in 1°? “ 10.00 Agpuj 1452 “ for gag.......5. seen 4 20x20x24 in. “ 220.50 Acker 1306 Condensing tube, Barrett.............0.++ ef 60 Agrig 1453 “ electric, 110 volts....... 20x20x24in. “ = 230.75 Aikso 1308 Condenser cylinder, glass............-...5 S. 1.00 Agsos . 1454 © FOP GASis sears seconds 4 18x14x35in. “ 238.00 Ailhk 1310 Burner shield. .200x90 mm“ 1.00 Agtor 1455 “ electric, 110 volts........18x14x35in. “261.50 -Aimazx 1312 - Cylinder, Barrett, 25 ml in 1-10 ml div.. ts 1.00 Agukz 1460 Capsules, Hearson, “A”......... 16°C. “ 2.40 Aimsm BIE Pigeon, sc ismarn a « vanes ee emt * “5.60 ee : a Fiennes on : ae Assrze 1316 Thermometer. water melting point........- is 6.00 Agwar Pscecres et 3 oe 40 Aimzy 1318 oe pe ie Paint every 7.00 Apa BON sce 45°C, “ 240 Aines 1320 Burner shield............. oo Bigxdin. “© 1.20 Agyom: wE itr BBC. 2.40 Ainhi 1322 Oven, Air melting point, of copper........- os 9.60 Agzfe MB eee eres 65°C. : 2.40 Ainla 1323 “Burner shield, for No. 1322 oven.......-.- “ 9.00 Ahaal Paka 75°C. 2.40 Ainot 1325 Copper cup........c0..0eeeeee eee 50m! “ 3.20 Ahamn aayat He gases 85°C. “ 2.40 Aintj 1326 Funnel,...........ccccscececeeees 40mm “ 35 Ahazm 1461 Gasoline gas burner, Hearson........... ge 20 Atoms 1328 Distilling tube, Hempel.............06-5+ ea, 40 Ahbsz | 1462 Shelf for Hearsonincubator .....9x9x12in. “ 1.50 Apdo 1330: “Asbestos ring, circalar........-- din, elt Abe Unie ae 1332 1“ 13.50 x15x18 in, i ie : ies benzol and mney aes a On ‘kei ; 20x20x24in “ 240 A 1334 “ “ ee ae “ 7.00 Aheoe 18x24x35in. “ 2.70 Aipuf A R T H U R H. T HoH Oo M A S§S Cc oO M Poh N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 1470 = Incubator, C.S & E. No. 2. .26x18x18in. ea. $100.00 Azque 1606 Sterilizer, Triple wall, elec. 220v. 1471 s ‘ “32. .26x18x18in. “ 112.50 Airky 12x18x9 in. ea. $143.00 Akycd 1472 a sf “ 31. .30x20x18in. “ 125.00 Arsen 1607 s “© ‘gag. 18x24x14in. “ 68.75 Akyga 1473 i is “41, .30x20x18in. “ 13750 Aisva 1608 re “elec. 110v. 1474 MS a “ 13. 30x36x18in. ‘ 225.00 Aitpl 18x24xl4in. “ 183.60 Akzey 1475 < S “ 33. 30x36x18in. ‘ 240.00 Aiult 1609 if eS a 220 1478 = Stand for C.S. & E. Incubator 26x18x18in. ‘ 12.50 Aiuys 18x24xl4in. “ 183.60 Alaev 30x20x18in. “ 12.50 Aivbm 1610 ie «© gas 24x30x18 in. “ 122.85 Alaru 30x36x18 in.“ 15.00 Aiveg 1614 if “© 30x36x20 in. “ = 195.00 Albho 1479 Shelf“ a $ 26x18x18in. “ 1.50 Airzp 1620 re Freas 110v....12x12x12in. ‘‘ 135.00 Alccr 30x20x18in. “ 2.00 Aiwhz 1621 “ » 220 v....12x12x12in. “ 135.00 Aleso 30x36x18 in.“ 3.00 Aiwok 1622 cf “ 110v....18x14x17in. ‘‘ 265.00 Aldle 1490 Incubator, Freas No. 26, 110 v..12x12x12 in. “ 140.00 Acard 1623 “ 220v....18x14x17in. “ 265.00 Aleer 1491 920 v..12x12x12 in. “140.00 Aiygz 1624 Shelf, for Freassterilizer...... 12x12x12in. “ 1.50 Alegs 1492 oe “97,110 v..16x16x14 in. ““ 220.00 Aryty 18x14x17in. “ 1.75 Aleim 1493 “ 920 v..16x16x14 in. ‘“ 220.00 Aiziu 1494 as “ — 28110 v..16x16x14 in. “ 235.00 Ajaht 1640 AUTOCLAVE, BeGs sterilizer. .744x9% in.“ 21.00 Alfhk 1495 Me «4 4 990 y,.16x16x14 in. “ 235.00 Ajaxm | 1644 N.I -12xllin. “ 45,00 Algih 1496 “ “© 40110 v..22x32x18 in. “ 390.00 Ajcaf 1645 do., but with gas equipment. . -..12xllin. “53.25 Alhfm 1497 ge «990 y .22x32x18 in. “ 390.00 Ajdew 1646 “©” kerosene 12xllin. “ 60.50 Aliav 1499 Shelf for Freas Incubator No.26............ “ 1.50 Ajehp 1647 Base for No. 1644 autoclave............... “ 7.60 Alirm Die eRe A es 1.75 Ajelh 1655 Autoclave, vertical, with removable OR ace rare ncseauns 1.75 Ajeoa lid, for gas heating......... 12x8in. “ 60.75 Aljly 40.. us 4.50 Ajetq 1656 do., for oil heating............. 12x8in. “ 65.50 Alkoq 1510 Incubator, C.8. &E.No.1....... ‘Qx7x7 in. “ 35.00 Ajfkt 1657 ae yeeass 24xllin. “ = 87.75 Allfi 1512 Coe ne 12x9x9in. “ 40.00 Ajhdu | 1658 fe bells ae 24xllin. “ 92.00 Allif 1513 Lamp, carbon eee for Nos. 1510 & 1512 “ 100 Ajidt 1659 “ elect. 110v.. 24xllin. “ 139.00 Almmt 1515 Incubator, C.S. & E. No. 11.15x12x10%4 in.“ 65.00 Ajipu 1660 “ 220v.. .24x1lin. “139.00 Alnem 1518 ff “ 62...17xl4x12in. “ 65.00 Ajjeq 1661 Autoclave, vertical, ‘with hinged lid, p 1520 oe Office, copper...... 10x12x10in. ‘ 51.25 Ajjyb for gas heating eter eens 12x8in. “* 64.75 Alner 1521 ee “with equip- 1662 Oss POM Ue east ie as ost 12x8in. “ 69.50 Alono mentfor gas 10x12x10in. “ 75.35 Ajleo 1663 BE ORS ee Latah Setar 24xllin, “ 94.50 Alpao 1522 as Office, copper...... 12x10x10in. “ 67.50 Ajmsk 1664 Ae SOI Loe screen nae 24xllin. “ 98.85 Alpyr 1523 . “with equip- 1665 “ elect. 110v................24xllin. “ = 145.75 Alram mentfor gas 12xl0x10in. “ 91.50 Ajnor 1666 ME 220'V 2 veeeee es 24xl1in. {145.75 Alskr 1530 “Field model, oil. .... 12x9x9in. “ = 111.25 Ajoid 1667 ie for gas heating. . Sue nen 26x14in. “121.50 Alide 1532 a «« 16x16x1Gin. “ 195.00 Ajoue 1668 He FO POUN Sie fees Aaa Go 26x14in. “ 126.00 Alubh 1533 “ “ “ gas... .16x16x16 in. “195.00 Ajppn 1669 “elect. 110v..... ..26x14in. “ 189.00 Aluog 1534 “ “elec. 10v. “in, “ 205.00 Ajrei 1679 “8 220v 26x14 in. “189.00 Alofy 1535 Oillamp for No. 1532 Incubator............ a 7.00 Ajiao 1680 Autoclave, 8. D. Horizontal, gas...24x2lin. “ 240.00 Alwez 1536 Gas burner for No. 1533 Incubator. . on 7.00 Ajuef 1681 steam.24x21 in. “ 252.00 Alzjo 1537 Electric heater for No. 1534 Incubator, lov. “ 16.00 Ajuuy 1682 s z % gas...28x23in. “ 340.00 Alyjn 1540 Incubator, HearsonModel C gasl2x12x14 in. “ 220.00 Ajryp 1683 a ‘ “steam.28x23 in, “ 355.00 Alyzk 1541 di “oil 12x12x14in. “ 220.00 Ajazyn 1684 * “ gas...28x26in. “ 450.00 Alznd 1542 a ot © “gasl5x15x18 in. “ 277.25 Ajype 1685 * “ steam.28x26in. “ 472.50 Amaet 1543 as 5 “oi 15x15x18in. “277.25 Ajzut 1691 “C.D. “ — gas...30x16in. “ 450.00 Amasg 1550 Gasregulator, Hearson..............5.... “18.50 Akamh | 1692 i in “ — steam.30x16in. “ 425.00 Ambhm 1552 Electric heater and regulator, C.S. ; & E.No. 73 for T10 a.c 60cyc. 6amp. “ . 290.00 Akazg 1700 STERILIZER, Arnold rectangular, : 1553 do., butfor110d.¢............ 10amp. “ 290.00 Akeuo with stand and burner. .1334x9x9 in, “75.00 Ameer 1554 Electric heater, C.S.&E.No.24... 110v. “ 16.00 Akebz | 1701 do.,noequipment.....- 1334x9x9 in. “ 67.50 Amday 1555 Actuating stove, C.S.4E.No.25.. 110v. “ = 16.00 Akeoy 1702 a with stand&burner1514x1274x12)4in. “ 81.00 Amdyb 1557 Electric solenoid, C.S.&E.No.18,d.c.,10 amp. “ 70.00 Akfes | 1703. — ‘‘noequipment.. ..1574x1274x124in. “73.00 Amemz 1558 do. butfora.c.,6amp.................. “75.00 Akgyc | 1704 with stand&burner1914x16}4x14}gin. “ 129.00 Amfaw 1705 “noequipment..... 1974x164 xl4lgin. “ 121.50 Amfsi Oa: Z comer : 1570 COAGULATOR, Hearson....... ig ADDS AM eect ieee em OF Tako deed 1571 Rack, for above. 10 tube “ 1.50 Akilb 1710 Sterilizer, Arnold ¢ ind 4 T th. a 5 i i iV : ; ylindrical, wi 1574 CS.&E.No.80. 110v. 120.00 Akizy outequi ‘ 113 Beet eee re n a pment........1134x1014 in. 31.50 Amifj 1575 Rack, forabove. 18 tube 10.00 Akker 1711 do 1214x1074in. “ 33.25 Amitk 1576 forgas..... 12x10x214in. “ 40.00 Akkve Re ea ars he Baer 1577 < “ “ complete ee 1720 SEROLOGICAL BATH, gasequipment.... “ 31.50 Amjhe with equipment........... 12x10x214 in. 2 53.25 Aklyx 1721 without equipment n 19.50 Amkar 1578 Coagulator for gas........-. 16x14x244 in. 48.00 Aknco 1723 “ “ — Kolmer, gas eq- 1579 complete : quipment “ 49.05 Amlei withequipment........... 16x14x214 in. “ 61.25 Aknyv 1724 ca “a “without 1588 Agar slanting device....... 1534x514x13 in. “ 12.00 Akopm equipment “ 44.55 Ammeh 1725 Test tube rack, Kolmer. . . .914x334x23/ in.“ 1.00 Amnao 1590 STERILIZER, HotAir. wes heated12x9x9 in.“ 15.75 Akplu 1726 Me . ee x514x23¢ in. “ 1.20 Amodh 1592 «a 10x12x Oin. “ = 27.35 Akqua | WaT “ “we | 944x914x286 in. 1.50 Amore 1593 aH asbestos covered 10x12x10in. “ 33.75 Akrol 1728 — Serological bath, without equipment ey dhe “ 87.75 Ampiw 1596 “ U. S.Army, gas. 12x18x9 in. “ 46.00 Aksta 1729 - f6 swith gag) ee eras: “91.35 Amgal 1597 ¢ i “and oil 1730 “Unit, combined, electric......... “133.80 Amged 12x18x9in “ 53.35 Aktmo 1731 i “without bath or racks.... “ 99.00 Amrix 1598 i ee 18x24x14 in,“ 62.00 Akudf 1732 ~—-Paraffine bath, withinset.................. a 12.40 Amspe 1599 a «and oil 1736 Serological bath, C.S.&E. No. 97, 18x24x14in. “ 76.75 Akuge gasheated............. 13x10x6in. “ 80.00 Amiko 1604 sf Triple wall, gas. .12x18x9 in. “ 55.35 Akviu 1737 do., No. 95, oil heated........ 13x10x6in. “ 80.00 Amukn 1605 “f “© elec. 110v. 1738 «98, elect. 110v....... 13x10x6in. “ 85.00 Amuyk 12x18x9in. “ 143.00 Akwym | 1739 «oe 4 33x1016x6 in. “ = 140.00 Amour oO M A § SM St 4a R T H UR Ha Tos A Gode Code Cat. Description Size Unit Price Wor é Unit Price Word No. ea. $21.60 Aotoa Ne. ae ee oer gg AL Bela UE Baa atte eel grams “2700 Aotig— BE Ee ET aes oe. $141.75 Amaio 600 grams “ 36.00 Aotei : B gasheated............... Giacks * ies rd 1500 grams i sree ae eye ee ee eee ee Oo “ is mM “ eg = a Capsules, Hearson.............. 374.0 ‘i 1.50 dae 1911 2 in glass case. . . a pam ¥ 45.00 A oust : “ 00 Aoun 1743....... “ 8.25 Amzyf 600 grams “54.0 Hed Sorlvicaltats OS. hm tah model... “ 242.00 Anama 1500 grams 72.00 Aouzd | SE eee sg S Amy Wicll med “Ames Anas aa ee oe re eg Paraffine embedding bath for No. 1756..... “92.00 Ancbu knife edges and planes, oO a rare 4050 Hooned 1760 Serological bath, ices ve - -9xOx5in. “ = 65.00 Ancyz gas eiee fiaaas eae “49.50 Aovze a“ “ “ No. 76, 110v..... “ 150.00 Andsk ae a Harvard trip eee laes Lkilo “ 9.00 Aownz De ck’. «ee S000 Ang Bie «oH agate eit Ae tae y . “ i ne! . 3 lo ie 1766 Paraffine compartment tray. . . . 10x10x4 in. 2 - ee 1918... pair 1.20 Aoruk EDDING OVEN nee tO Seatac aie. “iomnvage a ee ent, norings8x10x9 in. “ 26.40 Anfpo | 1922 i acl 2Ib. “ — 12,00 Aoyoo Se ae 8x10x9in. “ 30.40 Angke Bib. 14.0 Aogrp i oo aun, ‘with rings. ooh oe oe 2 pe 1923 Counter, 7 ‘n. pans... i Pe . ae ri “ ith rings. ..... 8x10x9 in. 5 fj Sin. pans... a i a Lee suena. bia in. “ 32.00 Aninp Qin. “... 10 Tb. a Hoes Hie “ gasequip.,norings. .... 10x12x10in. “ 36.00 Anizr 1924 ‘ Trip, 8in. “ ... 2b. ne aa ee “ noenin. ‘with rings... .10x12x10 in. “ = 35.20 aie Qin. “ ... 6 lb. i yeah ae es “ gasequip., with rings....10x12xl0in. “ 39.25 An in,“ a9 10 hb ;. ae ree 1780 eae ee 12in. “ 90.40 Anlia pes ‘ TPT, ae oe ee 5 1620 Apbs gasheating.............. Qin “ 90.40 Annch 2 pe eaematie 20 kilos « : peky te lete, WOwe 2 niin * SORE Ames) RL a Bl 1820 Aba 17 @ y By Weis hie cise 2) ‘ ; 7 % 210 grams “ i 1786 Paraffine embedding oven, ee 10% in. “ 69.00 Anogy | 1933 2 oe peat 120 grams “ 60.00 Apetd ene ie Stan deme | bee MEM RR Sen ie 187 o. v. “ 00 Anpra “ “ey . 2kilos “ . 180 Paraffine receptacle, CS.&E., No.38........ 50 ‘pr 1938 é a pans... ie in “3100 Ange “i a a” ; cy 2Qkilos “ 32.00 Ap pe ees os tae 7x4¥4in. “ 50.00 Angof | 1940 Be yee 434 kilos “ an ans 1792. Capsule, Hearson, for No. se bie is Labels “ 1.50 Anrzi ai ke é 6in, plates... i Eb ne sone ae 174 Paraffine embedding ae Hane Sdrawer “ 209.00 Ansur 1942 : wish ees Tkilo “ 36.00 Apicn without erie teeta Sdrawer “ 240.50 Antgy 1944 @ 5kilug “ 42.00 Apjiv ae os a be aa voosssseeee. SGrawer “ 276.75 Anudy “ Jolly spiral spring............. “59.00 Aplin 1796 oilequipment........ Sdrawer “ 304.75 Anurv 1948 . fic gravity, Westphal .... “ 3000 Aplog ay Sale ee ee ae) a nee « "6.00 Apmis 1800 “Rmbeddieg table, Ransom electric, “40.00 Anvhp | 1951 Reimann Sac oN iin set 3.00 Apnry be eae pecans 1, 33:00 Aniooz Ty oe scision...... 2.00. ea. 37.50 Apoig 1801 do., ywithout cover... ...2es sce erese “s 90 Anzye 1954 Balance, oes peri pre = een fi 2.00 Apown 1903 Theron ton ancl foro. 1800.00... 15 Amgon | 1988 ialdieelie Neel seh 158 depen 1803 Thermometer, angle, for No. 1800... . . “15.00 Anzgn | 1956 Set of riders, cow a éa, 3.00 Apgae 1804 Embedding table, electric, 110 v..... l4xdin. “ 2.15 Anztm | 1957 Theeriaciete, fot Beene nee © 200 Amos 1805 “ langular..-iOx?4g im. “350 Aoatt | 1088 Ja, for No svity, Bosker chainomatic oes ease Ch Boa ee “100.00 Anak 1818 Icechest................. “36.50 Aobiz SHOE RAGAS ce “85.00 Api ity 65 Ibs. do., but without case................+. 1 re eigen - capacl ‘i 00 Aocdo 1961 0., bu a: i ae . capacity 100 Ibs. “ sins Aocuf | 1962 Balance, Spec. gravity, Becker chainomatic 100.00 Apues 1824 Freezing closet..........-.2222. 00000 eee No. 100, with Se ee “ 85.00 Apuin “50.00 Aodpo | 1963 — do., but without, ea ee cues tees “20,00 Apumb 1840 BALANCE, Troemner No.35.........---- “ 85.00 Aoehe 1964 Glass case, for Nos. 196 and canis «19.00 Abyb 1842 “ a Male, haanie “ 105.00 Aoeud | 1965 ee oe eee “ 26.50 Aprya 1844 “ “ GTS SES i 198.00 Aofmt 1966 Balance, ple een hh ait fi 2.00 Apyke ee “ MET )e sche gnats 4 «Hand, 60 mm pans, 150 mm be: iy 1846 i “232.25 Aogge 1970 , 2.75 Apyno 1848 s ee ‘e palnaes erect “ 307.75 ora 80 mm pans, 200 mm beam 1850 “ PED A a ae ig achat ae a 100.00 Aokgi ‘ 91.75 None 1860 a — ieee “125.00 Avieg | 1972 BALANCE WEIGHTS gold plated 20 oe ae ce k Neo BALI © 150.00 Aoinz 100 grams “ 26.75 Apzos = 2 a sine, Be irs “ oe sense BAM . 01 ie “ 19.25 Aqaja 18 : i Crane eS 130.00 Aaiut | 1974 lacquered 20 grams “ 2050 Arcar Oe. ee eee | “198.00 Aotiv ms“ 22.75 Agarj be . ee pe, eee 200 grams “2028 Adaad 184 “Laboratory... ... +. --+--0s 0+ “ 36.00 Aonaj “ “imported. 50 grams“ 13.00 Agbyu 1895 a “ agate knifeedges.... 7 32.40 Aonsy | 1976 100 grams 16.25 Agecm 1896 4 Aluminum.......... 100rams “ a sone 1980 “ “ 5 ce 60 grams * 49.00 Agdlt io ‘ us 12, oon! N.P. L. certified......... i - 1990 “ Prescription. ceeeene a en “ 9.00 Aopbf rae grams 53.50 Aqdys 1901 Terra 4 “ 5.00 Aoprm 0 1902 “ Biaelinger Gatiel. 7-100 crs * fee 4ogod 1984 ae ee Gi evant ‘ 45.50 Ageol me ase, los “17500 Ao "sO grams S483 Algom 904 ie ‘ ” jlos “ 235.00 Aoryi : . certificate. 50 grams 0 "tory tales “20.00 dost | 1985 do, but with. of 8. certifca mee eae tee Teepe TE 35.08 Ae A R T H U R H. T H O M A _ § Cc O M P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 1986 Balance weights, Troemner, lac- 2048 Balance weights, brass ......... 200 gramea. $1.25 Arjwo Quer ed ss ectinncs. cranes eer 50 grams ea. $39.00 Aghyo 100 gram “ 1.00 Arjzi 100 grams “‘ 40.00 Agibi 50 gram “ 60 Arkda 200 grams ‘‘ = 43.25 Agifa 20 gram “ 30 Arkhs 1987 do., but with B. of S. certificate. 50 grams “48.35 Aqizp 10 gram “ 40 Arkkm 100 grams “50.10 Aqjaj 5 gram “ 39 Arknf 2000 Balance weights, fractionals. ..... 1-500 mgset 15.00 Agkis 2 gram ‘‘ 35 Arkso 2001 re " “aluminum. 1 mg ea. 20 Aglus 1 gram “ 30 Arka! 2mg “ 20 Agmag 2050 a “aluminum....... 500mg “ 12 Aripa 5mg “ 20 Agqmey 200mg “‘ 12 Arits 10mg “ 20 Agqmmi 100 mg “ 12 Arizk 20 mg “ 20 Agmyj 50mg “ 12 Armae 2002 o 4 “platinum... 50mg “ 65 Agnyt 20mg ‘ 12 Armew 100mg “ 1.00 Agody 10mg “ 12 Armhq 200mg “ 2.00 Agohg Smg “ 12 Armmg 500 mg “ 5.00 Agoli 2mg “ 12 Armpz 2004 = “gold plated. ..... 1 gram “ 80 Agpad 1mg “ 12 Armup 2 gram “ 90 Agpoa 2052 26 (AN DOK Got ects Se 50 grams set 3.50 Arnkj 5 gram “ 1.00 Agpuo 100 grams “‘ 4.00 Arnpy 10 gram “ 1.30 Aggba 200 grams “‘ 5.75 Arnuo 20 gram “ 1.60 Aggho 500 grams ‘‘ 7.25 Arnyg 50 gram “ 2.10 Aggme 1000 grams “ = 10.00 Aroba 100 gram ‘“ 2.90 Aggsr 2054 “ “no fractionals....100 grams “ 1.35 Aropz 2005 “lacquered. ...... lgram “ 00 Agrsg 200 grams ‘‘ 2.35. Arosr 2 gram “ 60 Agrui 500 grams “ 3.75 Arovl 5 gram “ 15 Agqsdu 1000 grams “‘ 5.75 Aroyf 10 gram “ 90 Agsik 2058 af “Metric fractionals 1t0500 mg “‘ 2.00 Arpna 20 gram “ 1.00 Agssp 2060 e - OP CARO Ty foeeces lkilo “ 4.10 Arges 50 gram “ 1.20 Agtaz 2kilos “ 5.50 Argik 100 gram “ 1.90 Agtij 5kilos “ 10.20 Argme 2010 “Riders, aluminum........ 14mg “ 20 Aquds 10 kilos “ 16.50 Arggt lmg “ 20 Agugm | 2066 7 “ Avoirdupois. 4% 02. to 1 Ib. “ 2.00 Arrhi 2mg “ 20 Agule ieee AAS 2.50 Arrkf 5mg “ 20 Aquov aeaneder ll eae 3.75 Arrny 6mg “ 20 Agusn tte itll Daa 6.50 Arrgs 10mg “‘ 20 Aquoh 2068 et uf s ..14 to 1-128 oz. “ 3.15 Arsfo. 12mg “ 20 Aquvax 2070 at “DP POV tenia ut 1 to 10 grains “‘ 80° Arsyb 2011 eg “ platinum......... 5mg “ 40 Aqwot 2072 Balancecover.............. 16x914x1714 in. ea. 3.50 Artsm 6mg “ 40 Aqwyz 18x914x1714 in. “‘ 3.50 Artwe 10mg “ A0 Agqzif 2074 Balance pans, glass.............. 2Mein. pair 1.00 Aruje 12mg “ 40 Agzos 3in. “ 1.00 Arumy 2020 “Weights, brass, in block... 20 gram set 7.25 Aqyka 2076 Mos RESPS CLASS cae roel tee des te ea. 18 Aruyz 50 gram “ 8.75 Agyor 2082 Barometer, Bunsen,empty................ e 6.00 Arorm 100 gram ‘“ 10.50 Aqysj 2083 o Observatory......... mm scale “ 46.00 Arwth 2021 4 ““ease.... 20 gram “ 9.00 Agzwa 2084 - i ...inchandmmseale “51.75 Arrry 50 gram “ 10.25 Arabo 2085 2 Dubebent. ce Aloo ken dess 3 3.00 Arymu 100 gram ‘“ 12.50 Araei 2086 ss oF -StraIGhG iM ik a eoteracnees 80 Aryzt 200 gram “ 17.50 Arahe 2087 oe Anaeroid......... 5in. diameter ‘ 13.50 Arzte 2028 Balance weights, normal sugar, cyl- 2088 ss pocketform........... . 15.00 Asage indrical, half normal... .13.024 grams ea. 1.50 Araub 2090 Battery, dry, Burgess Super-six... 6x214in. “ 1.00 Asauz do.,normal...............- 26.048 grams “ 2.00 Arazv 2091 tS SONAR Osert o nhs ean 6 volts “ 30.00 Asbmp 2029 “ get of twoinblock.................. set 5.25 Arbmr 2092 i ere een are 2volts “ 6.00 Ascga 2030 Balance weights, normal sugar, rec- 2094 “Binding posts........... Style A “ 18 Ascux tangular, half normal...... 13 grams ea. 2.00 Areck StyleB “ 20 Asdal dovsnormal was scissors a sas 26 grams “ 2.50 Arcfe Style C “ 25 Asdkr 2031 “ set of twoinblock............... “2. set 6.50 Ardan Style D “ 29 Asdnk 2032 Balance weights, factor, brass... . . Carbon ea. 1.75 Ardta StyleE “ 35 Asdsa PB 1% Carbon “ 1.75 Ardzs 2095 “ . Connectors............. Style A “ .20 Aseiu HN es V4 Silicon “ 1.75 Aream StyleB “ 25 Aselo “...Phosphorus “‘ 1.75 Aredg Style C “ 25 Asepf platinum... 7’; Silicon ‘ 8.00 Arehy 2096 a = Uishapedigees ct sieves aislon e 40 Asfit 2034 s ae Assay ton,s4,A.T. tol A.T. set 10.00 Areux 2097. Battery jars, cylindrical.......... 4x4in. “ 54 Asgis 4A.T. “ 13.00 Areyp 416x414 in. “ 60 Asgof 2036 “ “ Jgram to 0.1 gram “ 45.00 Arfge 4x5in. “ 72 Ashah 2044 Balance weights, brass........... 20 grams ‘“ 3.75 Arggy 5x7in. “ 1.10 Ashir 50 grams “‘ 4.50 Argnj 6x8in. “ 1.70 Ashoe 100 grams “‘ 5.50 Argrb 9x12 in.“ 4.00 Ashiu 200 grams ‘‘ 7.00 Argzp 9x15in. “ 4.10 Ashzm 500 grams ‘“ 9.00 Arhaj 2098 Bo” SE Sgqare sss uc ees 4x4x4in. “ 40 Asilk 1000 grams ‘‘ 12.00 Arhed 214x4lq¢x6in. “ -70 Asiod 2046 Balance weights, brass, in block... 20 gram se 2.25 Arhvs 4x4x8in. “ .15 Asirx 50 gram ‘“ 2.50 Arhzk 100 gram “ 3.00 Arice 2100 + BEAKERS, aluminum, with spout €0 ml “ 50 Asjkl 200 gram “ 5.00 Arify 125ml “ 65 Asjpa 500 gram “ 7.00 Arijq 250 ml “ 80 Asjug 1000 gram “ 10.00 Arimk 500 ml “ 1.20 Askae 2000 gram “ =: 15.00 Aripd 1000 ml “ 1.70 Askfu 2048 - ADS ee Riabtes ke 2000 gram ea. 4.50 Arjir 2102 a copper, withspout... 125ml “ 12 Askwl 1000 gram “‘ 3.75 Arjng 250ml “ 88 Aslev 500 gram “ 2.00 Arjry 500 ml “ 1.28 Aslpy A R T oe A N Y No. Description Size Code C I Unit ‘at. 2102 Beakers, copper, with spout 1000 ml a $184 die 22 B Description Size Unit Price os a “ ; eaker, h i si on 2104 Porcelain, without spout nal ne lice i a 18 ee oF re é 580ml . k ozs. . tiob 700ml “ ee ree 2143 Beaker, (Sugar-flask) with lip and oer aaee 970 ml “ spout...... we + 2106 “(Dye pots) aml Tag Aaa Page tte Som | ae ii ‘ some 2146 are) 2 32 ozs. 85 Aljne | 425ml“ 2.10 Asopo paque silica, low form, 2110 Beakers, Pyrex glass, low form, 1125 ml 3.30 Asotn MUD sentra 50ml “2.50 Atklg withspout............... 30ml “ 18 10) m1 : 2.75 Atker 50m “ 18 reese 2147 “ Transparent silica, low es ae isdn ” 19 Aspso form, withlip........ 5Oml “ = 9.75. thoi eae ated of Gee “a gay 0 BEL : m . times 400 ml i 30 Asafo L GLASS, low, ground rim... 23¢x4.in. 65 Atnaz oe 35 Asqle 2152 7 ee HR 2)6x5¥6 in. 95 Atnhl ae “argos ange. 4x6in. “ 2.80 Atoew a ae ae ae ' Th. ne. \. to7 Leal : 3 Aru ! sae : 8.50 re 2500 ml“ 1.20 Asyfm a “high ground dango “SxSine “250 Aliph ni : 1.40 Assje : ; 11x6 in: i 3.40 Atpou 2116 Beakers, Nonsol glass, low form, Aino iaibe in, a with spout............ ae 30 ml “ 15 Asti ne in,“ Se ae omit |S date ee Gee GOml“ AS dstos | 2154" square top. ee ae 120ml“ 118 Asta | 2156 Pe doxoin, “6.00 Ate 160ml : “19 Asucg - “ tubulated top 11x634 in. “ 3.40 Atsiob > a yo ‘Belin "1780 Atti Ke SULE “ “ “ im. . tth 200ml ; 23 Aa glass stopper. . Sx5in. “2.80 ies ae oe deups ie ss 3.50 Atuco 60m! 38 sua a! Goa dee. ae (ae 2158 jaunts re, ae en 38 Asvat | oe x5 in. 2.50 Atuvd sa 57 Asvid ct 1ix6in. * 3.30 Atuzt poco & 719 Asvpo 5x84 In. ae 6.30 Atvid 2122 Beakers, Pyrex glass, usual form 1.04 Aswek | 2159 eo “ Dialyzer. . va oe, eee withspout.............. Dwain gaia eee sae Se eee “e : 300 ml“ 2 an sa “double wall, stoppered or Se 400 ml ‘ 30 Asynp 300x120 mm “ 7.00 Atyyr per 32 Asyrh DIGG: Binddersentmal, 0°. 3 pcanue 8.50 Aizef edoml 35 aye | 2168 Blocks embedding, re... igaigb{in. 100" 350 Auapf 2128 000ml “54 Aszoh Sexdexigin. © 4.00 ae Beakers, Jr glass, usual form, “ 84x34%34 in. “ an peed without spout............ 100ml “ 19 Atadg 2170 B 1x1x34in. “ 7. j 1 4,10. 00 Auba; 150 ml ‘ "ol Ataky lowers, foot power............. 74 in, ea. 9.50 pie imal : 23 Atalg 9in. 12.50 Aubzo 200 ml _ 26 Ataoj 2171 “ “ © — onlegs 1lin. My 17.25 Aucai 400ml“ 30 Atard G8... Tin, “10.75 Aucer a aS (ee m - tazn 2172) = Rubber di in. “ . uddb | ; 8 on nl “ ‘38 Atbed ubber dises for foot blowers...... hie in. 50 Audus 2134 Beakers, Pyrex glass, (Dye pots) i ara aie 1434 in, {inn uae withoutapoat.. cg. 400ml “60 Atewr B Meteiontooe blowentins sess sie Svein A uae 600ml “ = .70. Atdaj 11ygin. “50 Aueur 2138 + Beakers, Conical (Assay flask) ser ontae 1414 in. 60 Auexl withoutspout............ , a : 25 Atede TE PRE aa oe ae - 18 Aufkl Mont“ 38 diet | 21 zoom “22 Ae 500ml “ “5 mk 7. _ Black’s, tin. ...... “ 15 ufay om aioe. | 2IT8 ? brags. sooo 10 dup 2139 do., but with spout............ cml “20 Aifoe. ? “Mouthpiece, hard rubber seal 120ml “ 25 Aifwo 6mm“ AO Aubin 250ml “ 35 Aigag 7mm“ 40 Auhlh rovo a a 3 dn Be “wooden nt é 1 an 2 “ 0 ; : . wt 2140 Beaker, heavy, with spout........ 7 ozs. “ 18 Athpa ant Az Auigg 2142. —- “ “ “ "& and flar- 2181 i Platt ; ; 8mm & 12 Auijk inglip... 2073. “ 16 Atiew 2182 “ Tip PN mee 7 1.90 Auiol 4ozs. “ 25 Atihg 2183 € Barve rene sient “ Aujna , OF DYASS........ 20 3.00 Aukes A R a H U R H . a H O M A S Cc O M P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 2188 Blowpipe Set, Butler..............0..... set $30.00 Aukul 2220 Bottles, narrow mouth, flat glass 2189 Handbook, Butler.......... copy 1.00 Auljh stoppers........... 1000ml ea. $0.60 Av'ck 2192 Boiler, or saucepan, enamelware.. . 2 qt. ea. 1.20 Aulvi 2020 ml “ 1.25 Aveur 534 qt. “ 2.30 Aulza ; 4000 ml “ 2.00 Aveyj 2193 “Double, enamelware....... 13 qt. “ 2.30 Aumov 2221 do.,butwidemouth............ 125ml “ 30 Avdqy 234 qt. “ 2.90 Aumrp 250ml “ 34 Avdug 354 qt. “ 4.00 Aumuj 500 ml “ AS Avdyt 1000 ml “ 65 Aveca 2200 BOTTLES, narrow mouth, flint glass 14 oz. doz. 59 Aunif 2000 ml! “ 1.35 Avefu loz. “ 63 Aunou 4000 ml “ 2.15 Aveio 202. “ -70 Aunsm | 2222 Bottles, narrow mouth, high mush- 302. “ 85 Aunvg room glass stopper...... 6 oz. “ A5 Aven 4oz. “ 97 Aunzy 8 oz. “ 50 Aveyh 6 oz. “ 1.10 Auocs 12 oz. “ 60 Anfev 8 oz. “ 1.32 Auofm 1 pt. “ 10 Aofhp 10 oz. “ 1.44 Auoig lqt. “ 80 Avfoa 12 02. “ 1.68 Auomy 2qt. “ 1.50 Avfuo 16 oz. “ 1.80 Auopr 1 gal. “ 2.15 Avgac 32 oz. “ 2.76 Auotj 2 gal. “ 4.35 Avgeu 64 oz. “ 3.60 Auoxd 3 gal. “ 7.00 Avgki 2201 ~~ Bottles, narrow mouth, amber glass 1 oz. doz. 63 Auprm | 2223 do., but wide mouth........... 6 oz. “ 48 Avhfr 202. “ 10 Aupug 8 oz. “ 60 Avhif 4oz. “ 97 Augau 12 oz. “ 65 Avhoy 602. “ 1.10 Auqgt 1 pt. “ 15 Avhsg 8 oz. “ 1.32 Augly 1 qt, “ 1.00 Avhwi 12 02. “ 1.68 Auggn 2qt. “ 1.70 Aviby 16 oz. “ 1.80 Augth 1 gal. “ 2.25 Avifq 3202. “ 2.76 Aurat 2 gal. “ 5.00 Arik 2202 ~~ Bottles, narrow mouth, green glass 8 02. ea. 10 Aurmy 3 gal. “ 8.40 Avime 16 02. “ 14 Aurpo 2224 Bottles, narrow mouth, high mush- 1 qt. “ 20 Aursi room glass stopper. ..... 1 0z.doz. 1.70 Avizb 1 gal. “ 33 Aurwa loz. “ 1.85 Avje lgal. “ 55 Ausas 202. “ 2.00 Arjld Qgal. “ 1.35 Ausek 4oz. “ 2.45 Avjow 5gal. “ 2.30 Ausic 602. “ 2.85 Aujso 2204 ~—_ Bottles, wide mouth, flint glass... . 14402. doz. .60 Ausvd 80z. “ 3.00 Avju loz. “ 65 Autar 1202. “ 3.72 Arkay 202. “ 72 Autez 16 oz. “ 4.20 Avkfo 3 oz. “ 88 Autmt 32 oz. “ 5.76 Avkle 4 oz. “ 1.00 Autri 2225 do., but widemouth........... oz. “ 1.80 Adlih 6 oz. “ 1.15 Autuc loz. “ 1.90 Auvlro 802. “ 1.32 Autyu 202. ‘ 2.15 Avlwe 12 oz. “ 1.68 Auudo 40z. “ 2.55 Avmaw 16 oz. “ 1.92 Auufg 6 oz. “ 2.90 Avmeo 2402. “ 2.64 Auujy 8 oz. “ 3.12 Avmje 3202. “ 2.88 Auunp 1202. “ 3.84 Avmot 64 oz. “ 3.72 Auurh 16 02. “ 4.20 Avmtj 2205 Bottles, wide mouth, amber glass. . loz. “ 65 Auveh 32 oz. “ 6.12 Avnav 202. “ 12 Auomr 2226 Bottles, wide mouth, amber glass, 4oz. “ 1.00 Auvg high mushroom glass stopper 1 oz. “ 1.90 Avnza 8 oz. “ 1.30 Auvua 4oz. “ 2.50 Avocg 16 oz. “ 1.90 Auvys 2234 ~~ Bottles, narrow mouth, flat glass 32 oz. “ 2.85 Auwmg stoppers, Jena glass. .... 250 ml ea. 15 Avogn 2206 Bottles, wide mouth, green glass. . . 8 oz. ea. 10 Auwsd 500ml “ 1.20 Avoth 16 02. “ 14 Auwzt 1000 ml “ 1.50 Avowb 1 qt. “ 22 Auxan 2000 ml “ 2.25 Avozo 16 gal. “ 33 Auxdh 3000 ml “ 2.75 Avpid lgal. “ 59 Auxix 5000 ml ‘ 3.50 Avpog 2 gal. “ 1.35 Auzmp | 2236 Bottles, aspirator, with outlet.... 14 liter “ -50 Anghe 5 gal. “ 2.30 Auzxre VY liter “ 60 Avgky 2208 Bottles, square, wide mouth... ... loz.doz. 65 Auyfe lliter “ 15 Avgop 202. “ 15 Auyiw liter “ 1.00 Avgud 402. “ 1.00 Auylg 4 liter ‘“ 1.80 Avrej 6 oz. “ 1.15 Auyoj Sliter “ 3.20 Aor 802. “ 1.20 Auyrd 12liter “ 4.50 Avroa 12 02. “ 1.68 Auyux 20 liter “ 10.00 Avsag 16 oz. “ 1.96 Auyyp 2237 do., but with nipple outlet... ... YY liter “ 40 Aossf 32 oz. “ 3.00 Auzch Yy liter “ 50 Arszr 2209 _ Bottle, rectangular, wide mouth... . 8 oz. “ 1.10 Auzty Wlter “ 60 Avteh 2212 “acid, narrow mouth, green lliter “ .15 Avimr glass, vertical glassstopper 14 pt. ea. 27 Avais 2liter “ 1.00 Artg 1 pt. “ -34 Avalm 4liter “‘ 2.00 Avtua lqt. “ 46 Avaof 8 liter ‘“ 3.60 Avtys 14 gal. “ 15 Avasz 2238 do., but graduated............. lliter ‘ 1.30 Avumg 1 gal. “ 1.05 Avavr 2liter ‘ 1.50 Avugh 2 gal. “ 2.15 Avayl Aliter “ 2.50 Avuib 2220 Bottles, narrow mouth, flat glass 2239 Bottles, aspirator, with g'ass s' op- stopper................ 125 ml “ 26 Avbzi perandstopcock........ 14 liter “ 2.00 Avvir 250 ml “ 33 Avcey Yliter “ 2.80 Avvpi 500 ml “ 43 Avcig lliter “ 3.00 Avvta : H Oo M A Ss Cc : ae O M P A N Y 0. Description Size Code Cat. 2239 Bottles, aspirator, with glass stop- Reece tere ee Description si cote per and stopcock... ... 2literea. $3.60 Avvyg _ | 2270 Bottles, oil sample, without corks sas 2 one sie yew ; . - el ’ . - G0Z. BS 2240 do, bat, = stopcock in metal ar sen ares 22 Bon La duae fii ne aaa I gai. “ | a oz.“ 1.75 Awsdi ° 2 pa! Ti 2 pare ae “ “ “ bio eee re 1.70 Auwsuz Care “garage | oa) eee eee oa, ee ae Gi PRUE RS eeS YB ce ; : a ee : es eae aol 3 Anyzp 2300 Bottles, Resarent, bag 7 200 ml 75. Awomn is repens, Beri curved pipette. .... as ‘13 4 vile black border, name and isis ee aight pipette ...............0.. “ 1 ‘wD ss symbol, label N 7 ulb and pipette, curved. ‘dew: oh dope * Ft Soml "66 Awe wasp atte AER gee ee ane 551 50ml “66 Atowee ee SOG Bape Ns eae Sy dete ae deen 2252 Botti ut without stopper........ 30 ml “ ae eas | aaa ori ottle, dropping. ............... 15ml “ a a 356 ae a finger pipette... smi“ 40 Audis eo ¢ al © “a8 duagh 30ml “AB Aandi 57 50m“ 166 Atal ms tntevtintbeen a ds ee ee «AB ‘Aawen ml“ 66 Awa 30ml 50 Awegv 560 50ml “ 6 m 66 Awz: Aes. Ts fae Sat Som 6 Aoi : : a 3 a “ 66 Awyea vs oe Bae oe ee 5Oml “ «35. Ann ; Seaee oom a2 dul a ae eae, 258 do, b 200ml“ “52 Amgss ofl" «66 doy ., butamber glass........... Mel eee | aL tba Bal aici tibet. bao Geen” oe 50ml“ 30 Awhid ee taal. ay gee 2260 Bottl : 100ml “ 35 Am 570 25 ml « ie atthe aracming, IabelNe: Toes: Sie. a dete ae 125 ml . 90 Awzwo po Saas i a pes ee 90 Avzzi aro Fil ah aah B73 et i 90 Axaca oe on wig 5 ml 90 Axafu ‘ 4.20 Awima 674 125ml © ow 50m ““ 4.20 Awipt srs 125ml“ 90 um Td es BOml “© 4.20 Aaris 576 125ml “ ‘90 Azape Cee BOmi “ 420 Awinb a dae Os BOml “420 Awigd 518 bmi“ 80 aan 25 ices 50ml “4.20 Amie a i ae at a Aujep 2 ree > 90 Asozf 32... «Om “4.20 Aun oT ee ON Mie 35... BOml “= 420 Auem eee dee 40... Som!“ 4.20 Auyya ss bmi “8D zen Ce sOml “ 420 Awkbu set 25m“ 80 re ae eee 5Oml “4.20 Aan 85 125m “ 90 dzmt > ane ae ia ae 56 128ml “ 90 Axert 80... 20m“ 420 Avlno se? 12bml“ 90 Azda adncls ml “ “ : 60... 50 ml “ 420 a sa 135 ml ‘90 Arde vee sOml “4.20 “Awlbt 590 al “ ae s oes 50 ml “ 4.20 ‘Aulen 591 125 ‘al s pas ro aks Aan a 8 lial de Bos bse val 420 Aw log a il : 90 Azele ae ae 5 A 505 pociie i 90 Axeox OO ces 30ml “© 420 Awmb 506 125ml “ 90 dae Dis sa som! “4.20 Ammen so” Bul“ 90 Aas 100... 30ml “ 4.20 Awmhg a sm“ 0 agp 105..... 5Oml “ 4.20 Awmka 599 125ml * ‘90 dan 190. ae 50ml “ = 4.20 Armor 600 125ml & 90 ajuk Ube cu 50ml “© = 4.20 Awmsj er ne 120... 50m! 420 Awmod 602 125ml“ 90 aa eens m - 130. . 50m! “ 130 ee oo 125m 0 dat BF cei 50ml “4.20 Awnhf 05 125ml“ 0 ail 1I5 50m! “ 4.20 Awnka a0 12bmi <0 zh 140... 50ml “ 4.20 Aronog co” 125m“ 90 Aah 142... 50ml “ 4.20 Awnrk es 1bml “90 ky ae 145.000. « 50ml “© 4.20 Am a0) bmi“ 90 Anis Bottles, ether, of glass.:.......... 250mlea. 1.20 ae c10 125ml“ a0 Asn 2264 “ — hardrubber,square...... le if iad ytd 612 eal ia ay ae Bom. 135 Awofh 613 125ml “ 20 hae eB: Arete eae cere ada 2967 e r Ue Sees : 1.50 Awgag a 125 ml 4 90 Azind Be) eet oie «1,00 Augpl | ee eee 1.00 Avorhb ogee “ae 125 ml 90 Aajos A R T H U R H. T H O M A S Cc O M P N Y Cat. Code Cat: Code No. Description Size Unit Price Word No. Description Size Unit Price Word 2301 Bottles, Reagent, white shield 2302 Bottles, Regent, white shield, black border, name and black border, name and symbol, label No. 619 125mlea. $0.90 Azkau symbol, label No. 696 250ml ea. $1.10 Aybum 620 125ml “ 90 Axkka 697 250ml “ 1.10 Aybag 621 125ml “ 90 Axkor 698 250ml “ 1.10 Aycby 622 125ml “ 90 Axkyx 699 250ml “ 1.10 Aycgo 623. 125ml “ 90 Axlid 700 250ml “ 1.10 Aycjt 624 125ml “ 90 Azlog 701, 250ml “ 1.10 Ayenz 625 125ml “ 90 Azlue 702 250ml “ 1.10 Ayctn 626 125ml “ 90 Axmas 703 250ml “ 1.10 Aydaz 627 125ml “ 90 Axmfi 704. 250ml “ 1.10 Aydfp 628 125ml “ 90 Axmja 705 250ml “ 1.10 Aydij 629 125ml “ 90 Axmop 706 250ml “ 1.10 Aydow 630 125ml “ 90 Axrmyn 707 = 250ml “ 1.10 Aydtm 631 125ml “ 90 Axnid 708 250ml “ 1.10 Aydze 632 125ml “ 90 Aante 709 250ml “ 1.10 Ayeay 633 125ml “ 90 Arnwy 710 250ml “ 1.10 Ayeeq 634. 125ml “ 90 Axobo 711 250ml “ 1.10 Ayehk 635 125ml “ 90 Axoei 712 250ml “ 1.10 Ayele 636 = 125ml “ 90 Axohe 713 250ml “ 1.10 Ayeov 637 125ml “ 90 Axolu 714. 250ml “ 1.10 Ayerp 638 125ml “ 90 Axoon 715 250ml “ 1.10 Ayeuj 639 125ml “ 90 Axosf 716 250ml “ 1.10 Ayexd 640 125ml “ 90 Axows 717-250 ml “ 1.10 Ayfet 641 125ml “ 90 Axpap 718 250ml “ 1.10 Ayffn 642 125ml “ 90 Axplt 719 250ml “ 1.10 Ayfih 643 125ml “ 90 Axprg 720 250ml “ 1.10 Ayfmz 644 125ml “ 90 Azqao 2303 do.,but.......... label No. 721 500ml “ 1.30 Aygeo 645 125ml “ 90 Axgha 722 500ml “ 1.30 Ayghi 646 125ml “ 90 Axgol 723 500ml “ 1.30 Aygla 647 125ml “ 90 Axgyr 724 500ml “ 1.30 Aygot 648 125ml “ 90 Axrix 725 500ml “ 1.30 Aygsi 649 125ml “ 90 Azria 726 500ml “ 1.30 Ayhav 650 125ml “ 90 Azrzo 727, 500ml “ 1.30 Ayhfl 651 125ml “ 90 Axshy 728 =©500ml “ 1.30 Ayhkb 2302 do.,but...........label No. 652 250ml “ 1.10 Axink 729 =500ml “ 1.30 Ayhnu 653 250ml “ 1.10 Aztsa 730 500ml “ 1.30 Ayhrm 654 250ml “ 1.10 Axtvw 731 500ml “ 1.30 Ayhug 655 250ml “ 1.10 Axuak 732 500ml “ 1.30 Ayibs 656 250ml “ 1.10 Azude 733 500ml “ 1.30 Ayiem 657 250ml “ 1.10 Azugy 734 500ml “ 1.30 Aythg 658 250ml “ 1.10 Arukg 735 500ml “ 1.30 Ayily 659 250ml “ 1.10 Azuoh 736 500ml “ 1.30 Ayign 660 250ml “ 1.10 Azusz 737. 500ml “ 1.30 Ayith 661 250ml “ 1.10 Axuot 738 = =©500ml “ 1.30 Ayixz 662 250ml “ 1.10 Axuyn 739° 500 ml “ 1.30 Ayjat 663 250ml: “ 1.10 Aaveb 740 500ml “ 1.30 Ayjel 664 250ml “ 1.10 Axvog 741 500ml “ 1.30 Ayjns 665 250ml “ 1.10 Azwai 742 500ml “ 1.30 Ayjqm 666 250ml “ 1.10 Azxwis 743° 500ml “ 1.30 Ayjue 667 250ml “ 1.10 Axwut 744. 500ml “ 1.30 Ayjzu 668 250ml “ 1.10 Azaed 745 500ml “ 1.30 Aykdm 669 250ml “ 1.10 Azzir 746 500ml “ 1.30 Aykhe 670 250ml “ 1.10 Aazga 747 ~—- 500ml “ 1.30 Aykky 671 250ml “ 1.10 Azzus 748 500ml “ 1.30 Aykop 672 250ml “ 1.10 Azzz 749 500ml “ 1.30 Ayksh 673 250ml “ 1.10 Azyda 750 500ml “ 1.30 Aykzt 674. 250ml “ 1.10 Axyhs 751 500ml “ 1.30 Ayldl 675 250ml “ 1.10 Azykm 752 500ml “ 1.30 Aylhd 676 =250ml “ 1.10 Azxynf 753 500ml “ 1.30 Ayllv 677 250ml “ 1.10 Azyrz 754 500ml “ 1.30 Aylpm 678 250ml “ 1.10 Azxyop 755 500ml “ 1.30 Aylte 679 250ml “ 1.10 Axyyj 756 500ml “ 1.30 Aylwy 680 250ml “ 1.10 Axzex 757 = 500ml “ 1.30 Aymag 681 250ml “ 1.10 Axzoc 758 500ml “ 1.30 Aymdk 682 250ml “ 1.10 Azzsu 759 500ml “ 1.30 Aymge 683 250ml “ 1.10 Axzyi 760 500ml “ 1.30 Aympy 684 250ml “ 1.10 Ayacy 761 500ml “ 1.30 Aymon 685 250ml “ 1.10 Ayaho 762 500ml “ 1.30 Aymsf 686 250ml “ 1.10 Ayaki 763 500ml “ 1.30 Aymyt 687 250ml “ 1.10 Ayand 764 500ml “ 1.30 Aynbn 688 250ml “ 1.10 Ayagu 765 500ml “ 1.30 Ayneh 689 250ml “ 1.10 Ayatp 766 500ml “ 1.30 Ayniz 690 250ml “ 1.10 Ayatj 767 500ml “ 1.30 Aynno 691 250ml “ 1.10 Ayazd 768 500ml “ 1.30 Aynrg 692 250ml “ 1.10 Aybet 769 500ml “ 1.30 Aynoy 693 250ml “ 1.10 Aybil 770 500ml “ 1.30 Aynzq 694 250ml “ 1.10 Aybna 771 500ml “ 1.30 Ayodi 695 250ml “ 1.10 Aybrs 772 ~~ 500ml “ 1.30 Ayoha 10 R TT H 11 tT 8 6 M A ¢ € 6 MP A NY Cat. No. Description Code Cat. 2303 Bottles, R oe ___ Size Unit Price Word = | No. Description Size Unit Price Word , Reagent, white shield : ~~” black border, name and _ | 2310 Bottles, Reagent, narrow mouth, symbol, label No. 773 500mlea. $1.30 Ayomg ground glass labels, No. 19 4.028. doz. $3.30 Azeco 2304 do, but.......... label No. 774 100ml“ 1.58 Aypan ee 3.30 Azehi 775 100ml“ 1.58 Aypfd a 330 fia 776 1000ml““ =—s-:1.58 A ae 30 Aa 777 1000ml “ 158 a 23 doz.“ 3.30 Azegp 78 100ml“ — 1.58 Aypuy ee ante 779 1000ml “ 1.58 Aypzo 26 Aca fe 3.30 Azewd 780 1000ml “ 158 A . 4028. 3.30 Azfav i yqga 27 ~— A ozs. “ 3.30 Azffl 782 100ml“ —«1.58 Aygo ae 8 aes 783 100ml“ 1.58 Aygua 2 ee. ae 784 100ml“ 1.58 gral | Gee asa dake 785 1000ml “ —1.58 Ayred a au 580 Aer 786 1000ml “ 1.58 Ayrha oe ag aa hace 787 1000ml “ 158 Ayrkr a pe i. et ae 788 1000ml “ —«1.58 Ayrnk 36 dos “3.30 ante 789 1000ml “ =—-1.58 Ayrsa 37 dom BBO ek 790 100ml“ 1.58 Ayrou eee Fedane 791 100ml “ 1.58 Ayrem a San dee 792 1000ml “ 1.58 Aysde 30 dons, 3.30 reve 793 1000ml “ —1.58 Aysgy oe BO ak 794 100ml“ —*1.58 Ayslo BL dan © 330 ad 795 1000ml “ 1.58 Ayspf a ae [She dee 796 1000ml “ —«1.58 Ayssz ae ae ee ee 797 000ml“ 1.58 -Aysyn 83 a San ek 798 1000ml “ 1.58 Ayteb 86 4ozs. ie 3.30 Azish 799 1000mi “ —«1.58 Aytjr 87 oe “ 330 ae 800 1000ml “ 1.58 Aytni ore ge 801 1000ml “ 1.58 Aytra ozs. E amt 02 1000ml “ —«1.58 Aytym 33 ce “ 330 ane 803 100ml“ 1.58 Ayuce < 2305 Bottles, Reagent, narrow mouth, : 06 re re 330 eeu blank, i.e. withoutlabel.. 50m! ® 35 Ayurz 97 ozs. “ 3.30 Azlap 125 ml i A2 Ayuor 100 4ozs. “ 3.30 Aailt 250 ml 60 Ayuyl 401 4ozs. “ 3.30 Azlgi 500 ml “ 70 Ayvez 404 4 ozs. “ 3.30 Azloy its eS . 1000 ml “ 95 Ayokn ie hes “ _ ee ottles, gent, wide mouth, ozs. “ E amha ‘ white atield ie onde i ie ec 3.30 Azmol name an ol, ) ozs. “ 3.30 Aznan label No.804 125ml“ = 1.00 Aywig 410 402s. “3.30 Aznix 805 125ml “ 1.00 Aywur 411 4ozs. “ 3.30 Aznre 806 125ml“ —«1.00 Ayer 412 4ozs. “3.30 Aznuy 807 125ml“ —«:1.00 Ayamh 4138 4ozs. “3.30 Aznzo 808 125ml“ 1.00 Ayxpa 414 dow. “3.30 Azoci. 809 125ml “ —:1.00 Ayzis 415 4ozs. “© = 3.30 Azoga 810 125ml“ —-:1.00 Ayzzk 416 ozs.“ 3.30 Azoks™ 811 125ml“ 1.00 Ayyea 417 4ozs. “© 3.30 Azonl 812 125ml“ —«1.00 Agyfu 419 4ozs. “3.30 Azogf 813 125ml“ = 1.00 Ayyto 420 4ozs. “ 3.30 Azotz 814. 125ml “ 1.00 Ayymg 421 4ozs.“ — 3.30 Azozr 815 125ml “ 1.00 Ayypz 422 4ozs. “ 3.30 Azpal 816 125ml “ 1.00 Ayytr 423 4ozs. “ 3.30 Azplp 817 el “1.00 Ayysj re ; ozs. “ an gre 818 125ml ‘ 1.00 Ayzev ozs. “ E 2p 819 125ml “ 1.00 Aves 2311 Bottles, Reagent, set of 40 No. 2310......... set 11.00 dae 2307 do., but. blank, i. e., without i 2312 “ narrow mouth, pe Sa ae = orlabel.......-++ 4 125 ml 53 Azaby ground glass labels, No. uh 3 oz. doz. 4.20 Azsea ottles, Reagent, narrow mouth, : : ozs. “ 4.20 Azsko ground glass labels, No. 1 4 028. doz. 3.30 Azagt - 103 = 8ozs. “ 4.20 Azsut 2 4ozs. “ 3.30 Azaul 104 8ozs. “ 4.20 Aztez 3 4Aozs. “ 3.30 Azayd 105 = 8 ozs. “ 4.20 Aztoe 4 4ozs. “ 3.30 Azber 106 8ozs. “ 4.20 Aztiu 5 doz. “ + 3.30 Azdij 107 8 ozs. “* 4.20 Aztyk 6 4ozs. “ 3.30 Azbow 108 8 ozs. “ 4.20 Azube 7 ~~ Aozs. “ 3.30 Azbso 109 8 ozs. “ 4.20 Azugu 8 . 4ozs. “ 3.30 Azbug 110 8ozs. “ 4.20 Azujo 9 4Aozs. “ 3.30 Azcay 111 = 8 ozs. “ 4.20 Azumi 10 402s. “ 3.30 Azefo 112 ° 8ozs. “ 4.20 Azura 11 4ozs.' “ 3.30 Azele: 114 Boas. “ 4.20 Azuop - 12 ° 4ozs. “ 3.30 ‘Azerp 116 8ozs. “ 4.20 Azuyj 13 4ozs. “ 3.30 Azcuj 122 8ozs. “ 4.20 Azvex 14 402s.“ 3.30 Aaddr 126 Boz.“ = 4.20 Azwlj 15 4ozs. “ 3.30 Azdlb 129 Bozs. “ 4.20 Azvpa 16 ozs. “ 3.30 Azdro 130 8ozs. “ 4.20 Azvvo 17 402s. 3.30 Azdya 131 8ozs. 4.20 Azwio 18 4ozs. “ 3.30 Azebu 145 = Boas. “ 4.20 Azwyh A R T H U R H. T H Oo M AS Cc O M P A N ¥ Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 2312 ~~ Bottles, Reagent, narrow mouth, 2338 = Bottle, Woulff, two necks...... 4000mlea. $3.75 Baszh ground glass labels, No. 150 8ozs.doz. $4.20 Azrin ‘ 8000 ml “ 6.00 Bater 151 8 ozs. “ 4.20 Azxyg 2339 do., with bottom tubulation..... 500 ml “ 1.80 Batts 152 8 ozs. “ 4.20 Azycy 1 a “ et pie 153 8 ozs. “ 4.20 Azygq ml “ : auae 154 8023. “ 4.20 Azyjk 4000 ml “ 5.00 Baudy 155 8ozs. ‘“ 4.20 Azyme 2340 Bottle, Woulff, threenecks....... . 250ml “ 1.60 Bauro 156 = 8 ozs. “ 4.20 Azypx 500 ml is 1.70 Bauup 2313 do.,but......... label No. 204 16 ozs. “ 5.85 Azzkh 1000 ml - 2.50 Bauxj 211 = 16 ozs. “ 5.85 Azzna fa a = rr aa 215 = 16 ozs. “ 5.85 Azzrs ms augr 216 = 16o0zs. “ 5.85 Azzum A : 8000 ml : 6.50 Banjl 217 1602s. “ 5.85 Baacu 2341 do., with bottom tubulation..... 500 ml 2.20 Bawba 218 1602s. “ 5.85 Baafo 1000 ml “ 3.30 Bawfs 219 = 16ozs. “ 5.85 Brajg 2000 ml eS 4.75 Bawim 220 = 1602s. “ 5.85 Baama 4000 ml 5.50 Bawlg 221 1602s. “ 5.85 Baapt 2350 Boxes, pastebcard, round......... 34x}4 1m. gross 60 Baxab 222 = 16 ozs. “ 5.85 Baasn ce Z a oe 223 =: 16 ozs. “ 5.85 Baavh 9X4 In. fy ax 204 J6ors “ 885 Baayd | 2352 “ “ — sliding.....2%4x1}4x84in. doz. © 25 Baxze 225 1602s. “ 5.85 Babdr ’ 234x134x Zin. “ 25 Bayes 226 = 16ozs. “ 5.85 Babgl 2354 UN POUNG sie ride eae haa 1 oz. “ 20 Baytn 227° 1602s.“ $85 Bablb Loz. 25 Baysf 229 1602s.“ 5.85. Babro 202. A0 Bazaz 230 = 16 ozs. “ 5.85 Babwe 4 oz. 60 Bazgn 239 = 1602s. “ 5.85 Bacaw 2356 «oe “deepform....... 3 oz. “ 60 Bazuk 240 6ozs. “ 5.85 Baceo 2357 Ao BE OE a liforminy ste ks 402. . 65 Bdaky 2314 do. but........ label No. 501 32028.“ 8.00 Bacuh | 2358 wood, round............. 78 02. 35 Bdayo ae peor NN Bade || 2360 BRUSHES oy liiter os cosas Qin.ea, .25 Bdemg 503 32 ozs. 8.00 Badfl i peer ne 5 “ 2361, ~ SS EE hace Rintae es 12in 35 Bdhuw ate Betas By eae 2362 . “four rows of bristle i. 50 Bdirb 505 32 ozs. “ 8.00 Badgo i ES ¥ 506 32ozs. “ 8.00 Badti 2363 Beaker............. 12in .27 Bdlyk 511 320zs. “ 8.00 Badxa 2364 e Jar, four rows of bristle......... a A5 Bdomg 2315 Bottles, R Cand th : ; 2365 “ with two tuftsonend....... + -50 Bdrab vUe a ee cals Maui: hace ee Hea 2366 “Beaker, long straighthandle.... “ 40 Bduke Bese aes DOS OD. Ce 65 Bacly | 2370 “Flask, pliableend............. “ 35 Bdyeq 302 4 ozs. 3.65 Baeqn “ “ a 37 Ba 303 Reng 3.65 Baeth OTe Se eye eae oe 7 in. a at E ‘i in. “ J yi 304 4ozs. “ 3.65 Baewb 18in. “ 42 Bd “ . . YYyr en oe fe 2374 “— flatbristle........... lin. “ 18 Beans : r Ilgin. “ 3 ea 312 4ozs. “ 3.65 Bafgh + a '30 B 313 dow. “3.65 Bafke ae ne eee 314 dors. 3.65 Bofus | 9375 “Camel hair, flat. ..... Yin. “ 25. Bebmr 2316 Bottles, Reagent, narrow mouth, with lin. “ ‘0 Bebgi special labels as ordered... . 4ozs. “ 5.75 Bagdm Lin. “ ‘50 Bebua 8 ozs. bs 7.15 Baghe Qin. “ 65 Bebys 16 ozs. © 8.60 Bagky 2376 “ “© round Win. “ 85 Becol Hom eS gen |) 237 i He QUIN eae 1gin.“ 60 Bedix 2317 do., but widemouth See nea re, 4ozs. 6.80 Bahhd 2378 “ “ “ “ 14 mm doz. 1.50 Bedzo 2318 Bottlecaps..................... a mm ten ve ree 18mm “ 1.68 Beeci renee) 5 a 22mm “ 2.16 Beega So oe ae 2379 “ “pencil... Small “ 20 Beetz 2 : Medium “ 40 B 2320 Bottles, specimen, wide mouth... 1840zs.doz. .70 Bairh Tage 55 Befal 214 ozs. “* -80 Baiub 2380 . Bristle, for assay buttons....... ea. 1.50 Befsa ‘ ‘ a a eM UBER tae oee tee I7in. “AB Beglo 2321 extra wide mouth ou ten a oar 2386 “ Test tube, with tuft... 134gin.doz. 90 Behfz ae : ays 2387 - a ie Re Yin. “ 80 Behvs 3 7 “ ae 100 ml ‘ 1.50 Bajxu 2388 “ “ “ sponge end. Qin. “ 90 Beijq 2322 4ozs.ea. 10 Bakol | 389 “ “© withtuft... 8l4in. “ 80 Beiyl 2324 “sputum, withoutcorks.... 2xlin. gross 5.50 Balfd Qin. “ ‘80 Bejez 2325 “ withcorks....... 2xlin. “ 7.25 Balta Vin. “ "80 Beit 2326 i. “square, with corks 10 ml doz. 85 Bamiw 2390 “ “ ‘sponge end. oan “ ‘67 Bathe 2328 vaccine, with rubber stopper opal ‘ Lies Hone 2391 “ «“ «with tuft... Qin. “ “60 Bekso m. ane) 2392 St ek dtars aan. e 85 Beli 232900 “" withoutrubber stopper 30ml “1.25 Bangf | 2394 oS Sha ee "72 Belzo 60ml “1.30 Banty | 2395 “ ——-‘Testtube...... 2... 13in. “ 50 Bemhq 2330 Special rubber stopper for No. 2329. ........ s 60 Baoiu 2396 “ “ (ecg he ee 3614 in. ea. 20 Bemul a Bottle, ee Never a ee ea. 2 pee 2398 “ cylinder............. llin. “ 12. Benkj m0 mn “wide mouth... 2 ozs. “ é ‘appe 14in. “ 20 Benne 2335 do., butnumbered............. 2ozs. “ 60 Bagko 2336 ~— Bottle, water sample, wide mouth. . 2ozs. “ .20 Barbf 2400 BURETTES, for pinchcock....25mlin1/10 “ 75 Beoba 2337 do., butnumbered............. 2ozs. “ 40 Barry 50mlin1/5 “ 1.00 Beofs 2338 Bottle, Woulff, twonecks......... 125 ml “ 1.25 Bisgu 50 mlin 1/10 “ 1.25 Beoim 250 ml “ 1.40 Basjo 100mlin1/5 “ 1.75 Beolg 500 ml “ 1.50 Basmi 2401 ‘ with pinchcock...25mlin 1/10 “ 1.40 Beoyf 1000 ml “ 1.90 Basgz 50mlin1/5 “ 1.65 Bepet 2000 ml “ 3.00 Basur 50 mlin 1/10 “ 1.90 Bepil 12 A R T H a = - Ke" s T H O M A 5 2401. Burette wi escription Cc Oo 2402 Burette, pa aot sass 100 ne 1/5 ale: Brice word Cat. M P A N_ Y¥ tube cock, with side ea. $2.40 B ns Sis - dbicseilepinohoosk epmd | 2498 Descripti .. with pinohooek.......... 50 ml in 1/5 Burette Fl on s ci ine 50 ml in 3 “ 1.25 Begdu am “ peel Seana ize Unit Price Word sdiepieahs 10 mlin 1/20 “ 1.55 Beraz ot ‘ Meniscus re: ‘a ieee ee 5 3 ee Os $0.50 Bilct apa 1.60 Berow | 2505 ee with glass plate... 10 Bitps 50 inl/5 “ 200 Berrq 510 B “ i es spring clip... e 1.00 Bimdg mlin 1/10“ 2, Oe Sent eatesees Chadd i 2405 do. is 2 75 mlin 1 /10 “ ac Berye 2512 - pal glass plate, only, f lock, for two burettes “a 3.00 Binnu ., With side tube... ase See | core poeate Ch aoe 2.90 Bioda esaetatics 25 mlin 1/10 “ 2.70 Besfo 2516 Opal glass plate, 0 cn boar for one burette . “ 50 Bios} a ae 50 ml in 1/10 “ 2.00 Bestl 3517 Burette support, nie or No. 2512... _“ 2.00 Biphf “ “ with 100mlin 1/5“ 2.25 Besyb | 2520 SPEND Bor an Base, for two burettes “ 30 Bigco © stopcock 3.00 Betep 2521 ee “ ay burette dea - 5.00 Big at 2408 Bure 50 mlin 1/10 “ ee Se ice adjustableclamp. .... 4.00 Birgk tte, amber glass with 100mlin 1/5 “ 4.50 Betwe 2523 “ow < amp for two burettes. ie 90 Bisdk 2410 i stopedck straight 5.75 Beuaw | 2526 : c. Noeeetstorone bursts 1.20 Biser 208 Pal aos: 50 mlin 1/10 “ a a ies RE UERER se ae pee stopcock atangle...... 50 mlin 1/10 pair 2.15 Beumy | 2530 Titrati * a AoE twoburettes... “ 1.70 Biuka 2418 - Be ot ees 50 ml in 1/10 8 9.00 Beuyz 2531 ‘itration outfit, compl with extra arms ele 1.70 Bivan 3-way stopcock i00mlin 1/5“ Bol Bas Support only, abused lete with glassware... “ 1.75 Biowy re 95 mlin 1/10 “ 308 Bot, | 2340 BURNE ? in No. 2530........... “ 22.50 Biwlg m9 i 50min 1/10 ce oer 2541 NER, Argand, with iron chimn ia AM ee diagonal bore sto’ 100 ml in 1/5 “ 40 Bewsj 2542 ~—‘Tro e a “of. © ti OY. 5-2 esis ae 2490 funnel te peock and 4.20 Bewvd 2543 «Gi m chimney, only, for ig ass a « 1.30 Biyfa Burette, 3-way sto Po siete s 50 mlin 1/10 “ m4 OB ass“ ly, for Argand burner... 7 1.30 Biyyn 2421 d he Soa side 4.00 Bexpo 2546 vurner, gas, on base. OO : ; is “ 25 Bizsy o., but with bulb. . e ig an 1/10 “ 4.00 2548 “ Micro. cree ~ pene 12in. “ ia ook Ee omar eatin in 1/10 “ By Beyek 2549 Glass chim: with glass china ... 2win. “ 5 aw} Scelbach,forpinsheodg 200 Bask | ge mes oy oN OD Blew ae ase 30 mlin 1/10 “ Pe ee Sin 138 Bley o., with pinchcock 100mlin 1/5“ 2.00 Bezng | 208 2 one 554 in. “ a Bliuf i eee ean eee 50 ml in 1/10 2.80 Besg | 28 ft nickel plated jin “55 Blot urette, Schellbach with a 1 /5 “ +2 has gas “ ta pine res Er 534 im, “ "2 ae sto J 60 Ze “ wi ‘I hess we dsatae aia aes saaeta, “ = 2g peock........ 95 mlin 1/10 “ 2562 a with nlokand stopcock...... : ee Bluml 2438 ~~ do.. wi 50 mlin 1/10 “ 2.80 Bhdah | 2963 “three tubes... 3in. “ - de _ do., with 3-way sto 100mlin 1/5“ 3.15 Bhdoe | 2364 a pie “ 15 Blyoc 2440 B y stopcock. .... 50 mlin 1/10 “ 3.80 Bhdyk 2565 “ io peda ERROR TA COW) coe cicct “ Ae Boaer surette, Schellbach with 3 100 ml in 1 /5 “ eo Bhenf 2568 “ i ae hen ese, Sa atiehie eoaeeaaa td “ an bog a “Ww: .t praenartey Che eae + “ a stopcock, zero ia Bherz | 2300 “ “ gasand air regulator vee 3.20 a acaacesl point 2572 : _ Porcelain 6in. bya: 2446 werflow cup. 50 ml in 1/10 “ 2572 Adjustable. som “ 450 Body Burette, straight stopcock, un wate 5 bie i Oke. Pte paces: a coe certifi , unoticia. . Aim ; : “ RA 2 GE Ns “ = A ertificate....... 10 mlin 1/20 “ 2576 ei wieieanasiennee 1.70 Boeri 25 mlin 1/10 “ 4.00 Bhicead | 2 cetylene.....eeeees - 1,60 Bofei 247 50 mlin 1/10 “ 5.40 Bhlij 2580 “Bo : Bunsen eens Gin. “ 220 feb do., but with Bu. of Stds 100mlin 1/5 “ 7.40 Bhmay 2582 a gen adjustable.................. “4.00 id cate. . certifi- / 8.20 Bhmuj 2584 “ Dp . iy Ty ee Arg ead “ L10 ced Dena 10 ml in 1/20 “ 25860 Detroitadjusiable ooo. “138 Bohep 25 mlin 1/10 “ 7.80 Bhoki | 2e5) “Universal, adjustable, wooden handle @ 498 Bae 50 mi 9.25 Bho 2590 it , wooden handle “ 25 Boilr 2450 Bur ; in 1/10 “ 1150 my “ Teelu three tub e145 Bojam 24 ette, Morse calibrati 100 mlin 1/5“ Se ee | eee es... 3 : ut calibrating........ me Ae 2 ia Eee Fee Sie eee eee ANS Bhudk imatco patent. . Tgin. “2.80 ae Three- ... 50,3 13.25 Bh 2596 @ Vee 25 mm “ 80 Boksa 2456 way stopcock f Ff and2 ml “ usf Fish 3.00 B Burette, Morse eS “14.50 Bhyok 2600 “ Bh er patent...... 30mm“ 4.25 olgy 2460 eon ae mie 4.00 Bhyss | eps “ Blueflame, without blast... 25 mm “198 Bomb 2462 ih Regen 102.5 ml “ 2602 «With blast « 2mm“ 3.25 lade cen) oh pee ashburn.....-.. ++ “10.25 Biais ‘aa 450 Bonko 2466 se Weighin Improved form. Oe a pe Biavr ac “ ae joint. oo Be ss ‘onke “ BEAM oie i ae sae 1 ery: 60 Bibga “ Rian Pee eo mm “ amo ce ee nee ae Bio a ae ce See “ oon . ‘ ngform........ 4in. “ 2 2472 Metalli only for No. 2470 ic, complete. .... «49 oak ee ae ae 13.60 Books lic el dees Uses 50 mli H .85 Bid: 610 Be Ain. “ pe 2480 Bur clamp “a in 1/10 “ 5 dpa 2 Ring f ; : 1.75 Bo nite, Squibb improved aro. dol 715 B 612 “ orm, with clam) Gin. “ qup 248 quibb improved zero... 25malin 1/10 & age Bigfu | 2613 Castle topfor'No.} Se es +30 Bolin a Clamp only fr No, er 50 ml in 1/10 “ a Be cut Dette pues e400 ps atte, Syuibb aro, originalform “130 if 2616 Eye Dacesoniie (on) CQ an acienn © 55 Bosyg 2485 a ginal form Bigha 2617 olid asbestos pad for N: 0.2612....... ‘i 35. Botsr 2492 only for No. 24 50 mlin 1/10 “ 2 Chimney, or trian No. 2612......00000.. a 20 Bouil 4 Burette pinch 0. 2484......50mlin 1/10 “ 8.00 Bigel 618 Burner tip, of gleholder................ "20 Bouwi ms ork attachment... “7.25 Bits | 2620 DiOU I eacihssiivas exannrs «20 Boone “Caps, of glass eee 30 Btigo 2621 a re “10 Bougn . ll yates oe ee |e ee ee “ Float, Vollhardt.... 23 mn 15 ae 2623 “ a ibs esti a i. 2 ce 2) seats Bel etase ‘ y cae ING we in, a 15 Bikke 2626 s vege eee ae di 30 Boydr Blowpipetip..... Win. “ 1 Boyro he aees ain. “ ‘16 Boyes 16 Bozig 13 A R hy H U R H. aE H O M A S Cc O M P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 2628 Burner MP riod bespacnaey Rraeeaeen tt: qpin.ea. $0.20 Braap 2723 Calcium chloride tubes, two bulb 150mmea. $0.20 Byevg 2630 Tube, yellow flame........ qein. “ .20 Braom 200 mm “ 30 Byeya 2631 “Star support. .........2.. zein. “ 25 Brebj 2726 sf s “ Ushaped.. 100 mm “ -20 Byfot 2632 o> Chimney Me tale va. eet | ayy. Sie ieeminds “68.50 Dyulj y 3724 Colorimeter, Kober improved model with 3828 Combustion Train, Stetser & Norton, with Klett top reader, original model..... “ 90.00 Durge Multiple Unit furnace and rheostat for 7 ae ¥ re ODE sic. eit carpe beonse « kes ‘ ae pes ae Uivolt Biss sot He : a0 ae ephelometer-colorimeter, Kober; 110volt.. “ 120.00 t o., but for 220 vo : . ust 3727, —C—i 6.50 Earst 3940 Condenser support, complete.............. ee 2.75 Ebymz 3889 Taperedclayconnectors. ........ 34 in. 2.00 Easft 3941 «large... 0s... “ 6.50 Ebzdo din, “ 2.25 Easin 15; “ce ein. 2.25 Easmf 3890 Rubber sleeves, only............. %4 in. “ me ee CONDUCTIVITY OF ELECTROLYTES iain. “ : atim 13in. a 2.00 Eatoz 3946 =‘ Vreeland Oscillator, L. & N. Simplified. ..... ea. $325.00 Ebzth 3891 Zinc jar, Fleming..................2.0000- ‘ 1.00 Eauct 3947 Motor generator, constant speed, 1000 cye.... “ 200.00 Ecajz 3892 Phosphoric Anhydride jar, Fleming......... “ 2.50 Eausg 3948 = Microphone bummer, (Audio oscillator)... . 32.00 Ecayu 3893 Mercury pressure gauge, Fleming........... a Ae a 3950 Tunable double telephone receiver.......... fi cree ae 3894 Stopcock, part C of Fleming Train ....... o 2. az 3951 Double telephonereceiver................. . ccud 3895 Mercury valve, for combustion trains... .... es 2 Eawmd 3952 A. C. galvanometer, portable, L. &. N., for ‘ th 3896 Zinc tube, Vanier...............-002 000 05- ig 89 Eawza low resistance bridges............... . 0.00 Eeduz 3897 Drying tube, Vanier, for sulphuric acid. ..... f 1.40 Eazxrp 3953 do., for high resistance bridges. . iM 60.00 Ecekt 3898 Mercury gauge and safety tube............. 1.50 Haygl 3954 Moving system, only, for No. 3952... * 20.00 i 3955 Be BOB “20.00 Ecga 3900 CONDENSERS, Liebig, of glass.. 200 mm “ 2.10 Eayui 3958 Kolrausch slide wire bridge, circular........ “125.00 Echfa 300 mm “ 3.10 Eayya 3959 “simplified... .. ee 70.00 Ecicf 400mm “ 4.20 Eazbu 3960 Unit type dial Wheatstone bridge.......... “t 70.00 Evipe 600 mm “ 6.50 Eazfm 3961 Half-meter bridge, with extension coils... .. 30.00 Ecjis 20 ‘T H OF M A 5S Cc O M P A R T H U _ R H. A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No, Description Size Unit Price Word 3966 Resistance box, Curtis coils...... 5dialea $370.00 Eckoe 4050 Corks, XXX quality, regular length No. 8 100 $1.00 Edurk 3967 “ Dial decade...... 4dial “ = 55.00 Eelgu 500 4.00 Edzas 3970 Variable air condenser........... 700 mmf “ 12.00 Ecmaf No. 9100 1.07 Edzek 3971 Vernier condenser............ 0.5 to 10 mmf “ 8.00 Eemyi 500 = 4.28 Edzie 3974 Conductivity cell, Washburn, Type A, with- No. 10 100 1.22 Edzmu out platinum. .................0005 5 17.75 Eenyh 500 = 4.88 Edxyy 3975 do., Type B, without platinum.......... “15.50 Ecolh No. 11 100 = 1.32 Edydi 3976 C, without platinum.......... «20.00 Eepac - 500 5.28 Edygf 3978 - Conductivity cell, Type LC, without platinum “ “20.00 Ecgoy No. 12100 =: 1.46 Edyka 3079 Glassell, only, for No.3978............... 15.00 Ecrik 500 5.84 Edyng 3980 Conductivity cell, Type MC, without pitioam 18.00 Eesij No. 13 100 =: 1.60 Edysg 3981 Glass cell, only, for No. SOG ots senenes 13.00 Ectay 500 = 6.40 Edyva 3982 Conductivity cell, Type HC, without platinum “ 24.00 Ectuj No. 14 100 1.86 Edyzs 3983 Glass cell only, for No. 3982............... a 19.00 Ecukd 500 744 Edzcem 3984 Conductivity cell, Henry, without platinum; No. 15 100 2.13 Edzge 20 mm electrode separation......... “18.00 Ecuya ~ 500 = 8.52 Edzjy 3985 do., but with 2 mm electrode separation. . “ 20.00 Ecvuh No. 16 100 2.64 Edanp 3986 Thermometer, Conductivity cell, 0-40°C..... “ 5.00 Ecrem 500 10.56 Edzrh 3987 Conductivity cell, U-type, without platinum 17.00 Ecyat No. 17 100 2.85 Edzyt 3988 Glass cell, only, for No. 3987.............. “13.00 Ecymo 500 11.40 Efabj 3989 Mercury tube, only, for No. 3987.......... “ 1.00 Eczas No. 18 100 3.06 Eyaed 3990 Conductivity cell, pipette form, without Plat- 500 12.24 Efahz MUM dine vaitiaie owes 20.00 Eczud No. 19 100 3.30 Efakr 3992 . “ Dipping form, without 500 13.20 Efank platinum............. 20.00 Edalt No. 20 100. 3.54 Efare 3994 " ee Kelley, without platinum “ 13.00 Edays 500 14.16 Efauw 3998 Conductivity cell, Ostwald, with gold elec- oe No. 22 ee a na odes: vi scccey es cesses Se cams aad ne z mn A a. 3999 do., with platinum electrodes............ “10.00 Edeyq No. 24100 4.50 Efbfa 4010 Constant temperature bath............... 100.00 Eddni 500 18.00 Efblo 4011 do., but with Beckmann thermometer, . No. 26 100 4.74 Efbrb rheostat and motor for 110 d.c...... * 169.50 Edebj 500 18.96 Efbal 4012 _do., but for 110 volt, 60 cyc., a.c......-. “169.50 Edenk 4052 Corks, special laboratory quality, regular 4014 Constant temperature bath, Freas Automatic; Verigth ac cedar danecatn eaves No. 3100 1.00 Hfesy for 110 volt, 60 cyc., a.¢..........-- “220.00 Edezm 500 4.00 Efdai 4015 do., but for 110 Volt d.C.. 0... ccecseees “220.00 Edfuv No. 4100 1.00 Efdfy 4016 Glass tank, only, for above....... 15x15 in. 13.90 Edgym 500 4.00 Efdko No. 5 100 1.00 Efdnh 4020 CONDUCTIVITY OUTFIT, for determina 500 =: 4.00 iat tion of absolute values with utmost No. 6100 1.00 Efeah accuracy; 110 d.¢........2---.s eee “1168.75 Edhre 500 4.00 Efedb 4021 do., but for 110 volt, 60 cyc., a.c........ “1168.75 Edifz: No. 7100 1.17 Efegu 4022 Shielded base, only, for above............- “$5.00 Edius 500 4.68 Efejp 4023 Armored lead wire, two conductor......... foot .25 Edjig No. 8100 1.42 Efeng 4024 Conductivity outfit for precise measurements; 500 5.68 Efega for 110 volt d. ¢.. ea. 324.00 Edkhr No. 9100 1.75. Efeus 4025 do., but for 110 volt, 60 a oe “324.00 Edlca 500 7.00 Efexm 4026 Conduetivity outfit for measurements of No. 10 100 2.00 Effag moderate accuracy........ ne i “201.00 Edlir 500 8.00 Effey outfit for efnatond use, wit! No. 11100 2.20 Efi as Pe caalltoe Se elcdeverdcansoneeisies Satie 150.50 Edmlh 500 = 8.80 ii 4028 — do., but without Audio oscillator......... “118.50 Ednew No. 12 100 2.41 Effod 4029 Conductivity outfit for measurements of mod- 500 ©: 9.64 Effsn erate accuracy, using 60 cyc. a. ¢. as No. 13100 2.68 Effxl source of €. M1. f.......0e eee eeeeeeee “149.25 Edoab 500 ~—«10. 2 Kigrx 4030 Titration Outfit using 60 cyc. No. 14100 3.10 Efgip ee source of e. m. f.........+++- ea. 214.90 Edona 500 12.40 Efgmh “e ; No. 15 100 3.56 Efgpa 4040 Cone Imhoff... .......00 2 eee eens 7 4.60 Edpdu 500 14.24 Efquq 4041 Wooden support for No. 4040.......----+- 3.50 Edggn No. 16100 4.41 Efgyi 4044 Contact key, single..........--+-2-cereres a 5.00 Edray 500 17.64 Efhdy 4045 Contact and short circuiting key, single..... ““ 16.00 Hdryb No. 17100 4.75 Efhgs 4046 Contact key, double.......----+++eeereee ff 9.00 Hdteo ‘ 500 19.00 Efhjm : No. 18 100 12 Efhob 4050 CORKS, XXX quality, regular length No.0 100 8 iat 5002048 Efhr No. 1100 38 Edugj No. 19 100 5.53 Efhup ” 500 «152 Edukb 500 22.12 Efhyh No. 2100 47 Edunu No. 20100 5.94 Efidz * "500 1.88 Edupg 500 23.76 Efigr No. 3100 54 Bdusk No. 22100 6.50 Efijl 500 2.16 Eduve god Ae aay No. 4 100 65 Edvau No. 24 100 = 7.00 Efipy * "500 2.60 Edoem 500 28.00 Efiuo No. 5 100 "76 Edvie No. 26 100 7.55 Efiai * 500 3104 Bdont 500 30.20 Hfjac No. 6 100 85 Edorl 4054 Corks, XXX quality, short taper...No. 0 100 36 Efirt 500 340 Hdwod 500 1.44 Efkab No. 7100 1.00 Eduwel No. 1100.36 Efkhn 500 «4.00 Edwme 5001.44 Efhif 21 A R T H U R H. T H Oo M A S Cc O M P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 4054 Corks, XXX quality, short taper No. 2100 $0.40 Efkoy 4058 Corks, XXX selected, flat, slight 500 1.60 Efksq taper............... 5gx23¢in. 10 $1.08 Egage No. 3 100 AS Efkwi 100 9.72 Egavs 500 1.80 Efldu Sgx27gin. 10 1.20 Egaym No. 4 100 51 Eflhm 4060 Corks, XXX selected, flat, slight 100 =: 10.80 Egbea 500 2.04 Efile COPOl wing CiaAeaines ¢ as 34x3 in. ea. 15 Egcoe No. 5100 63 Eflgt 10135 get 500 2.52 Eflyd 34x314 in. ea Et Egexn No. 6 100 67 Efmdt é . gdag 500 - 2.68 Efmij 34x3}4in. ea. 23 Egdey No. 7 100 83 Efmow — 10 2.87 Egdiq. 500 3.32 Efmuk 34x334 in. ea. 27 Egdmi No. 8 100 1.00 Efmyc _ 10 2.43 Egdsv 500 = 4.00 Efncw 34x4 in. a or oo No. 9 100 1.00 Efn, E gea, "500 4.00 nea 34x4}4 in. a ot he No. 10 100 =: 1.05 Efnsn : partis 500 4.20 nh 34x47 in. a a ae No. 11 100 L.A Efoct ‘ eae agen 500 4.44 ae Bs 34x434 in. ea. 49 Egepa No.12 100 122 Hof 10 4.41 Egels 0. . 0, 7 & 500 4.88 Bfomz 24x5in. e a el No. 13 100 1.35 foro ‘ a eg 50 5 40 . 34x51 in. ea. 63 Egfdy ; fot 10 5.67 Egfhg Nes a e i te 34x514 in. ea. 71 Egfnd No.15 100179 Efphe a ue a 50 716 ef ia 34x534 in. ea. 19 Egfyh No.16 100 182 Bea 107.11 Eggeo 0. : 0 : meee 500 7.68 Efpsl Ae ee cine “ y No. 17 100 2.07 Efgav | 4962 Cork sheet, XXX quality........4x12x!in. sheet 27 Eghey 500 8.28 Efgif i ~ : 4064 Cork borers, brass.............. set of 3 set 50 Eghtp No. 18 100 2.24 Efqos setot 6 “ 1.00 Eghaf 500 8.96 Efqti 3 ; ; tof 9 “ 1.75 Egibz No. 19 100 2.43 Efraw - 7 £12 2.60 Egiet 500 9.72 Efrem seto ges setof15 “ 3.50 Egihn No. 20 a ao ee 4066 Cork borers, steel tubing......... setof 3set 2.00 Egivk No. 22 100 3.00 a f setof 6 “ 3.25 Egiye 5 oe te setof 9 “ 3.50 Egjdu No. 24 ia are tae 4068 ol “brass tubing........ setof 6 “ 1.05 Egkaz ; ene setof 9 “ 1.75 Egkij oe ae aa oie setof12 “ 2.60 Egkmb 8 500 16.00 a gs 4070 Cork boring machine, with 8 borers........ ea. 23.00 Eglea fi 00 Effi 4071 Attachment for No. 4070 with 23 cutters... “ 3.50 Egmep 4056 Corks, XXX selected, slight taper, A 4072 Steel borers, only, for No. 4070... cetof& set 3.40 Egneo JALCORKS Ns chive acess eats 1x34 in. oe Ae ipa ee Cork borer sharpener................2.005 ea. 65 Egnyz . ifucn 4076 Cork press, rotary. ............00cec eee a 1.85 Egonu 4x74 1n. 100 1.03 Efufh 4078 Cork aaa a a Seige Waa meke een Bates < 20 Tepis _ 500 4.12 Efuid 4080 eS spelt pullnigs ices pov see tie west i 40 Egglz 1x1 in. 100 1.16 Efulv 4088 Counter, hand, Veeder, reads up to 9999.... “ 5.00 Egrhe 500 4.64 Efupm | 4090 Counting apparatus, Stewart, for 110 v..... ‘ 19.00 Egsen ¥gx1\ in. 100 142 Efute 4091 Reading lens, only, for No. 4090........... sf 3.00 Egswy 500 5.68 Hfuwy 4092 Incandescent lamp, for No. 4090........... ef 50 Egipl 16x14 in. 100 1.74 Efvag 4093 Ruled counting plate, for No. 4090......... “ 3.00 Eguijz _ 500 6.96 Efolu 4094 Counting apparatus, Wolffhuegel, complete.. “ 9.00 Eguey 16x13¢ in. 100 2.06 Efvub 4095 “Plate, only, glass, for No. 4094.... “ 1.70 Egvol Yr 8 g 500 8.24 Efweh 4096 r Apparatus, Jeffer, complete....... is 11.00 Egram 4058 Corks, XXX selected, flat, slight 4097 Plate, only, glass, for No. 4096.... “ 3.70 Egzyp taper...................56xL4in. 10 27 Efziy 4098 Me Cards Jefters zien cee dene tes ves < 10 Egykr 100 2.43 Efrol 4099 FM PPOSG 4 siiuies cacee asides fe 10 Egyws 5gx15¢in. 10 31 Efzyr 4100 “Chamber, Howard, without case.. “ 5.50 Egznj i 100 2.89 Efycj 4101 Cover giasses for Howard Counting 54x18¢ in. 10. 37 Efyfa 4 chamber, 33x33 mm es of mm “ aa a 100 3.33. Efyix Oey e ee eee eens eens ckness 1.0mm ‘“ 5 atu sgelzgin. 10 43 Efyir, | 4102 Capillary pipette... 02.2... 0.0lml “ 1.20 Babhs ; 100 3.87 Efyok 4103 Microslide (Guide plate)......... 2x41 in. “ 60 Ehbzl 5éx2in. 10 50 Efysc 4104 Moist chamber cabinet, Frocst.............. ss 35.00 Ehemh e199. 850 Hegre as Warming tabla. is saveisve'da avenue esac “25.00 Ehdae ys eet 106 Pipette, graduated to 1/20th ml............ af 50 Ehdst 5 1g in. 4 ,) : 749x276 in ies a ihe 4107 Guide, for ruling micro plates............. “ 9.00 Ehegr 54x21, in. 10 65 Efi 4108 Combined insulated carrying case and incu- EO en Be Bg ators ncat eae veaone en ccaen 50.00 Eheuo 54x23 in. 10 .14 Efztz 4110 CRUCIBLES, Assay, fire clay, 4 100 6.66 Egaaj without covers............ 5 grams doz. 15 Ehfim 54x2Voin. 10 83 Egaeb 10 grams “ 80 Ehfme 100 = 7.47 Egahv 15 grams “ 95 Ehfrt " 54x28Zin. 10 96 Egakp 20 grams “ 1.10 Ehfol 100 8.64 Egani 30 grams “ 1.35 Ehgab 22 R T H U R I. T 4H O M A_ 8S Cc O M P A N Y Cat. . Code Cat. No. Description Size Unit Price Word No. Des Word ; s cription Size Unit Price Word 4111 Covers for No. 4110 Crucibles.... A grams doz, $0.55 Ehgsq 4128 — Crucibles, Coors porcelain, low wide ae grams * 55 Ehgwi form, glazed, without covers 145mlea. $0.60 Zhwal 15 grams 65 Ehgec 265ml “ 20 grams “85 Ehh 2m 08 Baie Fs oo . ee oe 4130 do., but 8. C. P. porcelain. .... 2ml “ 08 Ehajs 4112 Crucibles, fire clay, French form, , ; ei a ae without covers............ Size D “ 95 Ehhaf el ee ee Sie E“ = 145 Ehiaz soni 20 Bhyd Size F “ 1.80 Ehidt 50 ml “ ‘40 i SizeG “ - 2.25 Ehign Q0ml “© 46 Elgar Size J“ 3.95 Ehijh \u5ml “156 Ehyml SizeK “ 5.40 Ehimb 265ml “ 68 Bhype Size L ‘ 7.50 Ehipu 4131 Covers for Nos. 4128 and 4130 : / a : : a Ee Crucibles, diameter....... 22mmdoz. .60 Ehzis 4113 Covers for No. 4112 Crucibles.... SizeD“ 85 Ehjle dium | eb Bho SizeE“ = 85 Ehjqr fon gai Size F “ 1.10 Ehjsn 52mm “ ‘84 EF iabd SizeG “ 1.25 Ehjyd 65mm“ 84 Bia Size J“ 2.20 Ehkep 7mm“ 120 Biaip ‘ SizeK “ 2.20 Ehkih 88mm“ 144 Bialh SieL“ 2.35 Ehkme 107mm “1.80 Binoc te 4a Fhium | 4134 Crucible, Gooch, poreelin, glazed, 4116 Crucibles, melting, alundum...... No. 5923 ea. 2.00 Ehlla with perorated hattom and : No. 3922 « "75, Ehlot _ two holes for suspending... 25 ml ea. A8 Hibea No. 6820 “ 125 Bhisl 4135 Crucible, Gooch, Coors porcelain, No. 6608 ‘ 200 Ehlyz with fixed perforated bottom, No.5144 “ 200 Ehmer without covers..........+. 10 ml : 36 Eibst 4118 Crucibles, Dixon plumbago....... No. 0“ . AS Ehmgo Bol a ae No. 00“ AS Bim oe apa : 54 Hic As . = lees 4136 do. but S.C. P. porcelain...... 10ml “36 Hieai No. 1“ 55 Ehnem ee ‘ $ aoe oe ; a e oa 4137 —do., of S. C. P. porcelain, but ace No 4“ 125 Ehn a with larger holes,i.e, 1mm 35 ml “ 50 Eieab No 5“ 128 Bhas} 4139 Perforated discs, porcelain. ...... 18 mm “ 23 Eiena | No. 6 1.70 Ehned a eee No. 7“ 1.80 Ehoat coc. oe i 24 Eien: Ne : fa as 4140 Crucible, Gooch, Atlasmodification 25m “ 1.00 Bifon Ne 1 | Bt Bho 4144 “Caldwell, Coors porcelain, iis: Gee 0S a ee’ ae ee i a , only, for No. 4144......... 24 Eiha: TD tk a free 4146 Cover, only, for No. 4144...........0.000, doz. 96 Hthor mae on Pt 4150 Crucible, Rose, porcelain, unglazed | 15mlea. 1.15 Kiifn No. 0000 ‘ 20 Ehpja 30ml “1.26 Biif ' : No. 1% 30 Ehpop | 4151 Cover, only, for No. 4150........ ism“ 07 Biya No, 2% 30 Ehprj 30ml “ 08 Biju Nee i 4152 Delivery tube, only, for No. 410, 15m!“ “86 Bifir s 5 j 30ml “ 86 Hijuh No. 5 S 40 Ehghd 4153 Rosecrucible, only............. 15ml “ 22 Biksk No. 6% 40 Ehgmt 30ml “ 32 Eikve Ne i S . Bheeg 4154 Crucibles, opaque silica, low, wide : 0. 4 qua shape, without covers...... 4ml “ 65 Hilka No. 9 50 Ehgzes 10ml “ 85 Bil No. 10“ 50 Ehrem isml “ “85 Bilth 4122 Crucibles, Coors porcelain, high 25ml “ 1.00 Bilyx ~ form, glazed, without covers 10ml “ 14 Ehrpl 40 ml “ 1.15 Bimbr / 15ml “ 18 Ehrsf 65 ml “ 1.65 Eimhf 30 ml “ 29 Ehroz 145ml “ 2.00 Eimme ; 2 57 mI “ 36 Ehrar 4155 Covers, for No. 4154 Crucible. ... 4ml “ 55 Einco 4124 —do., but S. C. P. porcelain..... 10ml “ 14 Ehsom . ml “ 55 Einfi 15 ml : 17 Ehste 15 ml “ 55 Einja 30 ml ‘ 29 Ehsys 25ml “ 65 Einar : 57 ml “ 36 Ehidi 40 ml “ 85 Eingl 4125 Covers, for Nos. 4122 and 4124 65ml * 85 Einif Crucibles, diameter......... 35mm doz. 60 Ehizp 145ml “ 85 Hinat . 42 mm “ 60 Ehucej | 4156 Crucibles, transparent silica, low, 47 mm 60 Ehufd wide shape, without covers. 10ml “ 1.90 Eiong 59mm “ 96 Ehuiz 15ml “ 2.50 Eiosg 4128 — Crucibles, Coors porcelain, low wide a5ml “3.15 Fiore form, glazed, without covers 2.5mlea. = «11 Ehawu 40ml“ 4.70 Eipag Sm “ 14 Ehuzo 65ml “ 6.25 Hinge 12ml “ 18 Ehoga 4157 Covers, for No. 4156 Crucible.... 10m! “ 1.55 Eipyt 1g Dy’ 17m! “ 22 Ehyju 15ml “ 1.90 Highn 30m! 30 Ehonl 25m “ 2.05 Higiz BO ml “ Al Ehosb 40 ml “ 2.40 Higom 90 ml “ 52 Ehvar 65 ml “ 3.15 Eigse 23 24 A R T H U R H. T H O M A Ss Cc O M P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 4158 —Crucibles, opaque silica, high form, 4186 Crucible, silver, without cover, ap- without covers............ 20mlea. $1.35 Eirku prox. weight 58grams... 75mlea. $0.12 Ejpha 30 ml “ 1.35 Eirpj 80 grams... 100ml “ 12 Ejpls 50 ml “ 1.65 Eirsd 120grams.... 150ml “ 12 Ejpuz 4159 Covers, for No. 4158 Crucible. ... 20 ml “ 55 Eismp 4187 Covers, for No. 4186 Crucibles 30ml “ 09 Eispi weight 10 grams... . 20 ml “ 12 Ejriw 50 ml “ 65 Lista 13 grams. ... 30 ml “ (12 Ejrux 4160 Crucibles, transparent silica, high l5grams.... 50 ml “ 12, Ejsed form, without covers....... 10 ml “ 1.90 Eitmo 2lgrams.... 75ml “ 12 Ejsnk 15ml “ 2.50 Eitph 28grams.... 100ml “ 12 Ejsty 20ml “ 2.80 Eitux Sees 150ml “ 12 Eitak 30 ml “ 3.15 Hitzn 4188 Crucible, nickel, without cover. 20 ml “ 1.00 Ejubh 50 ml “ 5.95 Eiuch 30 ml “ 1.10 Ejufz 4161 Covers, for No. 4160 Crucibles. . . 10m! “ 1.55 Hiuge 50 ml “ 1.20 Ejuit 153ml “ 1.90 Eiuiy 75 ml “ 1.80 Ejuln 20ml “ 2.05 Eiuxq 100 ml “ 2.10 Ejuog 30 ml “ 2.40 Eivht 150 ml “ 3.50 Ejusy 50 ml “ 3.15 Eivfa 250 ml “ 5.30 Ejuzo 4162 Crucible, Caldwell, opaque silica, . . : 500 ml : 8.00 Ejoai without disc, diameter...... 45 mm “ 1.15 Eivyn 4189 Covers for No. 4188 Crucible... .. 20 ml 5: 12 Ejwez 4163 Crucible, Gooch, transparent silica, 30ml i 14 Ejwng with perforated bottom... . 20 ml “ 6.75 Bizfy 50 ml i 16 Hjwus 4170 Crucibles, alundum RA-84, with- 75 ml © 18 Ejxag OubicoverscAconessceiace No. 6295 “ 35 Hiyed 100 ml © 30 Hizey No. 10351 “ 35 Eiygu 150ml “ 1.00 Liajo No. 10363 “ 35 Eiysp 250 ml 1.20 Ejzur No. 5202 “ 35 Eiyng Rees er, 500 ml 1.50 Ejyaf No. 6457 “ 35 Kiyry 4190 Crucible, Kawin, nickel........ 28x15 mm 50 Ejyne No. 9007 “ 40 Eiyrg 4191 “Gooch, nickel.......... 30ml “ 2.70 Ejzae No. 7040 “ AO Eiyyk 4192 “ Pennock-Martin, nickel, No. 5203 “ AQ Eizbe On standis soe. ceeieds aiiet 40 ml “ 3.30 Ekabz No. 12017 “ 50 Eizgu 4193 do., but without stand.......... 40 ml “ 2.30 Ekaoy No. 11921 “ 65 Eizgjo 4194 Crucible, Skidmore, iron. ... L602. “ 1.20 Ekbdu No. 7731“ 1.25 Eizmi Boz.“ 1.80 Ekbik 4171 Covers, only, for No. 4170....... No. 5203 “ 15 Ejadz 4196 Crucible holder, Bailey...........-...005, ih 25 Ekeow No. 5202 “ 75 Ejagr 4198 Spencer. ... ie 80 Ekdov 4172 Crucible, alundum filtering, with- 4200 nf me SWHAIEY oe eh rcdnte i op ean ie te es 40 Ekeih out covers, Mixture RA-98 4202 es “Opaque silica.... 3x3in. “ 90 Ekewe PONOUS ee: ec dee eed No. 5204 “ 35 Ejavm 4x4in, “ 1.25 Ehkezy No. 5205 “ 40 Ejayg 4204 e “Sargent plain type 4173 do., but Mixture RA-360 mediumNo. 5204 “ 35 Ejeab for crucibles... 27mm “ 35 Ekfrn No. 5205 “ 40 Ejelf 35mm “ 40 Ekfyz 4174 «@« RA-84 dense... No. 5204 “ 35 Ejdle 40 mm “ 50 Ekgif No. 5205 “ AO Ejdyd 4206 " “Sargent replaceable 4175 Covers, only, for above.......... No. 5204 “ 05 Ejeld flange type... 27 mm “ 1.60 Ekhnt No. 5205 “ 05 Ejeow 35 mm “ 1.60 Ekhuf 4178 Crucible, clay filterings Johnson. . 25 ml “ 1.00 Ejfay 40 mm “ 1.60 Ekibr 4189 “ Jron, without cover..... 20 ml ‘ 7 Ejget 50 ml “ 25 Ejgou 4210 CRUSHER, or bucking board, iron 18x24in. “ 13.25 Ekins 100 ml “ 31 Ejgya 4212 do., but of chrome steel................. “ 90.00 Ekigm 200 ml “ 42 Ejhbu 4214 Crusher, Weatherhead patent............. “© 38.75 Ekiue 400 ml “ 56 Ejhhi 4216 Mill, Assay, hand power.................- & 18.00 Ekixy 4181 Covers, for No. 4180 Crucibies. . . 20 ml “ 10 Ejiav 4217 Plates, only. for No. 4216...... Set of two 4.00 Ekjel: 50 ml “ 10 Ejidp 4220 Grinding apparatus with agate mortar and 100ml “ 10 Ejiif pestle 414 in. diameter.............. ea. 83.50 Ekkhd 200 ml ‘ 13) Ejimz 4222 Crusher, Case patent....................- Ms 75.00 Ekkzs 400 ml “ 16 Ejigo 4224 Pulverizer, Iler’s patent disc; 6 in. discs.... “‘ 100.00 Eklon 4182 Crucible, copper, without cover. .. 20 ml “ 40 Eqjka 4225 Discs, only, for No. 4224; 6 in. diameter... . set 6.00 Ekmom 30 ml “ 96 Ejjor 4228 Sample grinder, Braun No. 6-R............ ea. 89.00 Eknfe 50 ml “ 12 Eqjuf 4229 Grinding plates for No. 4228; 6 in. diam... . set 9.00 Ekodh 75 ml “ 88 Ejkel 4232 Coal grinder, Braun No. 6-C.............. ea. 100.00 Ekopi 100 ml “ 96 Ejkiz 4233 ee BE GEO Ra rescore reais “110.00 Ekpoj 150ml “ 1.36 Ejkog 4234 Grinding plates for Nos. .4232 and 4233..... set. 9.00 Ekrde 200 mil ‘“ 1.60 Ejks: 4236 Iron ore grinder, Braun No. 6-S........... ea. 130.00 Eksml 250ml “ 2.16 Ejlas 4237 Grinding plates for No. 4236; 6 in. diam.... set. 21.00 Ektko 500 ml! “ 2.65 Ejlft 4238 Iron ore grinder, Braun No. 7............. ea. 190.00 Ekuht 4183 Covers, for No. 4182 Crucibles. . . 20 ml “ 25 Hjmib 4239 Grinding plates for No. 4238; 7 in. diam ... set 26.00 Ekuxg 30ml “ 25 Ejmte 4240 Coal grinder, Braun No. 7-C.............. ea. 195.00 Ekvur 50 ml “ 32 Ejmwy | 4241 Grinding plates for No. 4240; 7in.diam.... set 9.00 Ekady 75 ml “ 40 Ejnbo 4244 Laboratory grinder, Braun No. 7-A........ ea. 195.00 Ekyad 100ml “ -56 Ejnjy 4245 Grinding plates for No. 4244; 7 in. diam... . set 9.00 Ekyne 150ml “ 64 Ejnpl 4246 Simplex crusher, Braun, hand power....... ea. 74.00 Ekzeu 200 ml “ 80 Ejnzr 4247 do., but for hand and power driving. . “78.00 Elabx 250 ml “ 1.04 Ejocl 4248 do., but for power driving, with tight ‘and 500 ml ‘ 1.12 Ejogd: loose pulleys... ............00 00 eee zy 91.00 Elany 4186 Crucible, silver, without cover, ap- 4250 Pulverizer, Braun type UA..............- “148.00 Elaza prox. weight 25grams.... 20mlgram 12. Ejose 4251 Grinding plates for No. 4250.............. set 9.00 Elbrp 42 grams... 30 ml “ 12 Ejovy 4254 Chipmunk crusher, Braun VC No. 12, 45 grams... 50 ml “ 12 Ejozq FOR POWER vie scocccnn Sodas cdenbe ote ie cm ea. 107.00 Elchj 25 A R T H VU R H. T H O M A 5S c oO M P A N Y he iaeeine Code Cat. Code 0. ; escription Size Unit Price Word No. Description Size Unit Price Word 4255 Chipmunk crusher, Braun VC No. 14, for 4344 Culture dishes, small 50x10 mm pair $0.20 Emurs power, with tight and loose pulleys... ea. $125.00 Eldaw t "75x10 mm ‘O4 Emad 4256 do. WO No. 16, for power... 190.00 Elds! ice os eee 4257 do., WC No. 18, for power, with tight and 4345 " “ large... ..... 120x15 mm “ ‘40 Emygn ., loose pulleys. ...................665 “220.00 Eleif 150x15 mm “ 60 Emyjh 4260 Milling machine, Johnson...............:. s 60.00 Eleug 150x20 mm “ 10 Emymb 4261 Cutters, only, for No. 4260................ oe 4.80 Elfka 200x20 mm “ 1.00 Bel 4264 Mill, porcelain.................. 170mm “ = 40.00 Elggh 4346 f “with knob. . .150x50 mm ea 1.00 Emzeq 4265 “ Laboratory, hand power............. a 9.00 Elgxy "00x70 mm “1.50 Emahk 4266 Toothed worm, only, for No. 4265. ........ ‘ 1.25 Elhmu 240x80 mm “ 250 Emama 4267 Plain worm, only, for No. 4265............ es 1.25 Elidl 4348 s “without knob150x50 mm “ ‘90 Enacq 4268 Mill, laboratory electric; 110 volt d.c....... “ 155.00 Elisq 200x70 mm “ 1.25 Enafk 4269 —_ do., but for 110 volt, 60 cyc., a.c........ “160.00 Eljia 240x80 mm “ 2.00 Enaje 4270 Grinding unit, toothed worm, for No, 4268.. “ 8.00 Elklt 4350 Culture dish holder, Ravenel.............. 10 Enaxz 4271 “plain worm, for No. 4268.... “ 8.00 Ellbm 4352 ke tin......... 3x4g5 in. “ 15 Encas 4272 Toothed worm, rae for No. 4268......... “2.00 Ellsd 4353 we gin, 20 Encsh 4273 Plain worm, only, for No. 4268............ “2.00 Elmix | 4354 « — Box, sheetiton..... Oxdigin. “ 3.20 Endri 4274 Grinding plates, only, for No. 4268......... pair 1.50 Elmzo 4355, me SE copper. . 9x4iyin. “ 440 Eneet 4277 =Pulverizing mill.......................... ea. 45.00 Elnsb 4356 gS SE WOM a ay ses oo | 5M x2x714 in. “ 2.00 Enerh 4278 Granulating mill......................... 45.00 Elogz 4357 «© copper... ... 514x2x734 in, “ 3.60 Enfom 4279 Grinders, pulverizing, for No. 4277......... pair 5.50 Eloty 4358 « «with door...... 8x5in. “ 14.40 Engls 4280 “granulating, for No. 4278 ...... 1+ @a, 3.00 Elpgy 4359 FO RO GS oe SA ak ey 7x5x5 in. “ 12.40 Engsd 4281 Mill, drug, height”.............. 1234 in. “ 9.00 Elgeb 4360 Culturedishcarrier..............--...0055 “40.00 Enhkt 15in. “ = 11.00 Elajr 20% in. “ 18.00 Elgog 4366 Culture Flask, Kolle, Pyrex glass. 320ml ea. 15 Eniam 4282 Grinder, meat.................. 1b. “ 3.15 Elrrz 4368 “ Miquel........... 50ml “ 40 Enioj . 2hb. “ 4.50 Elsah 100ml “ 50 Enird 3lb. “ 6.50 Elsir 4370 “ 3 “ pipetteform......... ae 50 Enjiv 4283 Bagasse cutter..............0--..00000005 “22.00 Elida 4372 so “ Pasteur.......-.. 100ml “ 30 Enkbi 4284 Mill, sugar cane, hand power.............. “63.00 Elis 250ml “ 60 Enkfa 4285 Disintegrator, Warmouth-Hyatt........... «415.00 Eluip 500ml “ 80 Enklo 4286 Bacteria grinder, White, complete.......... “47.00 Eluvo 1000 ml “‘ 1.00 Enkrb 4287 Glass globe, only, for No. 4286............ “a 12.00 Eloli 4374 Culture tube, Roux............ 150x20 mm * ss 18 Enlpe 4288 Marbles, only, for No. 4286........... Box of 25 13.50 Elev | 4378 Cups, porous, unglazed porcelain. .75x38 mm ° 29 Ennah 4299 Ball mill, single specimen................. ea. 22.00 Elxki 100x52 mm ‘ AA Ennhi 4291 Porcelain jar, only, for No. 4290........... “ 7.50 Elydv ie am - 65 Ennoe 4292 e “ with pebbles, gasket, ete.. € 8.37 Elyrs 177x76 mm “ 50 Enniu 4294 Ball mill, single assay, Type A............. “50.00 Elzgo' 200x80 mm “ 1.38 Ennam 4295 Porcelain jar, only, for No. 4294... ....... “14.50 Elzzb 4380 Cupels, composite, top diam... . . . lin. 100 2.40 Enolk 4296 “ “ with pebbles, gasket, ete...... “17.55 Emalb 1g in. “ 2.70 Enood 4297 Porcelain pebbles............... Yin. lb. 15 Emazy 1M in. “ 3.00 Enoso agin. “ .70 Embeo Ug in. * 3.30 Enown lin. “ 69 Embig 134 in. “ 3.60 Enozh 14in. “ 30 Embmy 2in. “ 4.25 Enphr Jin. “ 25 Embrn 4382 “Bone ash, top diam........ Lin. doz. 30 Engli 4298 Flint pebbles...............--.- Small “ 10 Emerm lyin. “ 35 Engst Large “ 10 Emeug 14 in. 40 Enrev 4300 Jar, bacteria grinding, Army Medical School : 14 in. “ AS Enrru model, Pyrex glass...........--+--- ea. 12.20 Emdrl 134 in. © 50 Ensac 4302 Bacteria grinder, single jar.........-.-..-- “41.15 Emejb 2in. 5 Ensew 4303 —do., but without jar.............-.-.--- «35.50 Emewa 234 in, 1.00 Enski 4304 Balls, of carbon chrome alloy steel 34 in. 100 3.00 Emfnr 4384 Cupel moulds, of brass.......... 144 in. ea. 4.00 Enthn Yin. 100 6.00 Emghd Ug in. * 4.10 Entmd 4306 Bacteria grinder, triple jar............---- ea. 93.00 Emhms a . 134 in. © 5.50 Eniqu 4307 —do., but without jars................--5 “56.50 Emikb | 4386 Rake,iron.............++ 24 in. 10 Enuhm 4388 “ Shovel, iron....... kan Balada 24in. “ 10 Enuyj 4314. CRYOSCOPE, with thermometer and plat- / : inum stirrer...........-+ 36.50 Emivy 4390 CYLINDERS, with spout...... 100x25 mm “ 18 Enorg 4316 x Hortvet, complete outfit. . 75.00 Emjuz 125x25 mm “ 18 Enon 4317 ie “« ~ simplified outfit. . 30.00 Emkuy 125x40 mm “ 22 Envea 4318 a Thermometer. PET’ to to—2° C. © 20.00 Emmch 150x25 mm “ 18 Enwle 4319 “ +30° to—30°C. “ 6.00 Emmzq 150x40 mm “ 26 Enwyb 175x30 mm “ .28 Enxep 4330 CULTURE DISHES, Petri..... 100x10 mm pair = .25 Emoed 200x380 mm ““ 28 Enzlb ; 100x15 mm “ 25 Emoho 210x40 mm “ 30 Enzwe 4332 a “ Bottoms, only 95x10 mm ea. 12 Emoxo 250x40 mm “ 35 Enyaw 95x15 mm ‘ 12 Empat 260x45 mm ‘“ 40 Enydg 4333 “ “ ops, only 100x10 mm “ 13 Empyl 300x40 mm “ 40 Enyhi . 100x15 mm “ 13 Emgir 300x50 mm “ A8 Enyla 4334 a “~~ Covers of earthenware, : 315x65 mm “ .10 Enyot unglazed..... 97 mm “ 10 Emryj 350x50 mm “ 56 Enysl 103 mm “ 10 Emshr 365x65 mm “ 80 Enyxb 4335 “ Covers, of earthenware, 375x50 mm “ 60 Enzer unglazed inside but 450x50 mm “ 10 Enzif glazed on top and sides 500x50 mm “ 80 Enzos 103 mm ‘ 5 Emsyi 4392 Cylinders, with oe riM......... 100x25 mm ‘‘ 18 Hoaek 4338 a “ Gabritschewsky 100 mm 1.50, Emitr 125x25 mm “ -18 Eoaic 4340 a “Of plate glass 100x10 mm “pair 1.00 Emauin 125x40 mm “ 22 Eoamu 434] iS “ Bottom, only, of No. 4340 ea. 60 Emuxi 150x25 mm “ 18 Eoapn 4342 “Top, only, of No. 4340. . 60 Emvoz 150x40 mm “ .26 Eoash A R T H U R He. T H Oo M A SS c O OM P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 4392 Cylinders with top rim 175x30 mm ea. $0.28 Hoavb : 200x30 mm ‘‘ 28 Eoazt 4423 Decomposrrion of Water Apparatus, 210x40 mm ‘‘ 30 Eobdl on wooden base...........--..+0005 ea. $12.00 Houkk 950x40 mm “ 35 Kobhd ee a but baie sorte ee eae ; ie 1b ie 60x45 mm “ ‘40 Eobmt composition of water apparatus, Hoffman “ : vow 300x40 mm “ "40 Eobri 4426 Deflagration spoon, brass........ 241 & e a 30050 mm “ A8 Eobue | 4427 do. butofiron............... gin. “ 5 Eoxfl 315x65 mm “ 10 Hobyu lin. “ 15 EHornu 350x50 mm “ 56 Eocbo 4428 Deflagration and combustion spoon, Parker. “ 25 Eoyem 365x65 mm “ 80 Eocge 4429 < Spoon, brass; wooden handle... “ 05 Eoyth 375x50 mm “ 60 Eocjy 4432 Demijohns, glass, willow covered... 1 gal. a 1.70 Eozmy 450x50 mm ‘“ 10 Eocenp 2 gal. ‘ a) Here 500x50 mm “ 80 Evesf le cee 4394 Cylinders, enlarged top..... .300x60x40 mm “ 70 Eodno | 4436 DESICCATOR, Scheibler ‘ica an Bees 350x63x45 mm “ -10 Eodrg ; oP Ra tases Sha 125mm “ 1.80 fee 1 400x70x45 mm “ 1.00 Eodvy 150 mm “ 2.20 Boaub 4396 > ether aon 200x100 mm “ 1.40 Eoemg Sane: A pees 300x75 mm ‘ 1.80 Eoerf 250mm“ 7.80 aha 300x100 mm ‘2.40 Eoeez | 4438 = do., with tubulation in lid...... 150mm“ 5.50 Eels 375x75 mm 2.50 Eoezp 200 mm “ 8.00 Epcuz _ G00x75 mm ““ 3.00 Hofah 350 mm “12.00 Epdef 4398 with side funnel... .... ee 65 Lofwu 4439 do., with stopcock and hook.... 150 mm “ 7.35 Epehy 150 mm -15 Eogam 200mm “ = 10.25 Epel 4400 a Outlet ic.ccisg ess 4x15in. “2.00 Eogyp 250mm “15:78 Epeo} “ ‘ 7 9 “ . 4402 Dispensing. ......---- ee a te Be pe 4440 Desiccator, Scheibler, Pyrex glass, : 100ml “ 6.00 Bohea with tubulation in lid...... 200mm “ =—-:12.50 Epfkr 4404 Cle duated, Brown- Duvel. “ 1.00 ae 4441 do., but with stopcock and hook. 200 mm “ 18.00 Epggy 4406 “ 95 ml ‘60 Fou! 4442 Desiccator, Scheibler, ordinary glass 100 mm “ 1.00 Ephog 4408 “Single grad., with spout 5 a - 36 Eojsy = ae “ He ae 10ml “ 38 Eokai ‘ “ ; 15ml “ "38. Eokfy 4444 ‘ Atwater ia. iscece.. 100 mm 4.00 Epirz 25 ml = 40 Eokko 4446 Desiccator, Fruehling & Schultz, 50 ml 48 Eoknh with porcelain plate....... 200 mm ea. 7.70 Epjyk 100 ml ‘ 60 Eokut 250 mm ‘ 11.25 Epkbi 200 ml ye 15 Eokyl 4447 do., but without pore. plate.... 200 mm “ 5.70 Eplpa 250 ml x 88 Eoled 250 mm “ 8.75 Eplug 500 ml : 1.10 Eotht 4448 Desiccator, Fruehling & Schultz, 1000 ml < 1.85 Eoloe with tubulation in lid and 2000 ml ¢ 3.60 Eolry with porcelain plate....... 200 mm “ 8.60 Epmst ; 3000 ml Ae 5.20 Eolvg 250 mm “ 15.30 Epmef 4410 “ Double grad., with spout 10ml 46 Eomjo 4449 do., but without porcelain plate 200 mm “ 6.60 Epnyg 25 ml i‘ 48 Eommi 250 mm “ 12.80 Epoba 50 ml ‘ 56 Eomur 4450 Desiccator, Fruehling & Schultz, 100 ml i 13 Eomyj with stopcock and hook in 200 ml “ “95 Honda ’ lid and porcelain plate... . 200mm “ = 11.00 Eposr 250 ml : 1.10 Eonip 250 mm “ 19.00 Epowj 500 ml . 1.40 Eonlj 4451 do., but without pore. plate.... 200 mm “ 9.00 Eppoy 1000 ml ; 2.35 Eonpa 250 mm ‘ 16.50 Eppsq 2000 ml 2 4.25 Eonts 4454 Desiccator plates, porcelain, with 4412 Cylinders, single grad., stoppered . 10 ml 60 Eoojm three small feet, large holes 95mm “ 90 Epgqyd 25 ml c 68 Eoond 115 mm “ 1.02 Eprhl 50 ml i 10 Eooga : 140 mm “ 1.50 Eprow 100 ml i 90 Eootr 4455 do., without feet, small holes.... 140 mm “ 1.75 Epsqr 150 ml 1.05 Eoowl 190 mm “ 2.10 Epsil 200 ml - 1.20 Eoozf 230 mm ‘“ 2.52 Eptax 250 ml 1.40 Eopft 4456 do., without feet, large holes.... 190 mm “‘ 2.10 Epuaw 500 ml : 1.65 Eopin 230 mm “ 2.52 Epudq 1000 ml f 2.80 Eopmf 4458 Desiccator,complete..................... as 4.00 Epusl 2000 ml : 4.80 Eoppy 4460 Dialyzer, complete.....................-. ve 7.00 Eporm 4414 “Double grad., stoppered 10ml 10 Eogim 4462 “Tubing, parchment... . 45mm meter .10 Epzel ’ 25 ml e .16 Eoglg 55 mm “ 15 Epark 50: ml i 80 Eogrt 4463 “Paper, parchment... ... 31x34in. sheet .25 Epyic 100 ml x 1.05 Eogol 4466 Diamond, for writing on glass............. ea. 3.00 Epyud 250 ml , 1.60 Eorbz 4468 Dies, Figures, 0 to9............. 1 in. set 1.60 Epzwy 500 ml : 2.00 Eoret Yin. “ 1.75 Eqack 1000 ml 3.20 Eorkh 4469 “ Letters, Ato Z............ Yin. “ 4.20 Eqazp 2000 ml - 5.50 Eorna lin. “ 6.25 Eqbix 4416 « — Tmmunity unit....... 10 ml : 2.00 Eosby 4472 Diffusion shells, Whatman........ 90x16 mm 25 6.00 Eqded 20 ml “ 2.30 Eosgo 100x35 mm ‘“ 14.00 Eqdoi 30m . 2.40 Eosji 4473 Digester, Spencer rotary for bagasse analysis ea. 225.00 Egepf 40 ml 2.50 Eosnz 4474 do., but with motor, speed reducing gear 50ml “ 2.60 Eosin and leather belting. For 110 volt d.c. “ 267.75 Eqhez 60 ml 2.10 Eoszb 4475 do., but for 110 volt, 60 cycle, a.c....... “ 268.00 Egikm 70 ml “ 2.80 Eotgn 80 ml 2.80 Eotld 4480 DISHES, Coors porcelain, with spout 35ml “ 14 Eqjyt 90 ml 2.80 Eotow 60 ml “ 22 Eqkrv 100ml “ 2.80 Eotso 80 ml “ 24 Eqlad 26 Cc A R T H U R H. T H O M A S&S Oo M P A N_ Y Cat. ; Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 4480 Dishes, Coors porcelain, with spout 100mlea. $0.36 Egloa 4502 Dish, opaque silica, sugar analysis 40ml ea. $1.65 Hrosn — 140 mi “ 42 Eqmac | 4503 “tannin analysis 75m “‘ 1.65 Erplb 175ml “ 48 EHqmme | 4504 ig ee “with handle. . 30ml “ 1.65 Ergbu 210ml “ 54 Eqmyf 4506 “ Crystallizing, glass......... 90x50 mm “ 16, Erquh 300 ml “ 66 Egnil | 100x50 mm “ 20 Errbt 385 ml “ 84 Eqnum 125x65 mm “ 36 Erren 535 ml “ 96 Eqodu 150x75 mm “ A8 Errif 765 ml “ 1.08 Eqohm 170x90 mm “ 64 Errnu 1285 ml “ 1.44 Egqole 190x100 mm “ 80 Errsk 1430ml “1.80 Eqosp 4507 do., but of Pyrex glass......... 90x50 mm “ 45 Ersly 2200 ml “ 2.16 Eqoyd : 100x50 mm “ 55 Ersqn 3250 ml “ 3.60 Egper 125x65 mm “ 85 Ersuf 5700 ml “ 4.80 Eqpuk 150x75 mm “ 1.15 Ertbr — 10,000ml “ =: 10.80 Egrep 170x90 mm “ 1.25 Erthf ; 16,500 ml “ 21.60 Egrya 190x100 mm “ 1.50 Ertmy 4481 Dishes, S.C. P. porcelain, with spout 35 ml “ 21 Equf 4508 Dish, Tanning, thin glass........ 50x70 mm “ 25 Eruco 60 ml “ 24 Egtrm 4509 “Pyrex glass.......50x70 mm “ A5 Erurj 80 ml 26 Equdo 4510 “ Evaporating, Pyrex glass... 80x45 mm “ 35 Ervib 100 mt “ 30 Equgi 90x50 mm “ 40 Brort 140ml “ 39 Equly 100x55 mm “ AS Ervva 175 ml “ 48 Equrl 125x65 mm “ 15 Erwag 210ml “ oT Equuf 150x80 mm “ 1.00 Erwon 300ml “ 66 Equav 200x100 mm “ 1.30 Erzap 385 ml “ 88 Eqvid 4512 Dish,preparation,ground on cover 36x24 mm “ 25 Eryao 535ml “ 1.00 Egqwas 50x30 mm “ 80 Erydi 690 ml “ 1.10 Eqwop 60x35 mm “ 40 Eryha 765 ml ‘“ 1.25 Equwyv 4513 do., but tallform............. 60x90 mm “ 40 Erzan 1285 ml “ 1.66 Egaxlv 4514 Dish, Stender, ground on plate 1430 ml “ 2.10 Equyu glass cover............... 50x30 mm “ 35 Erzyg 2200ml “ 3.08 Eqylu 60x35 mm “ AO Esabi 3250 ml “ 485 Eqyub 80x40 mm “ 50 Esafa 5700 ml “ aH Eqalt 100x50 mm “ 60 Esajs 10,000ml “ 15.40 Egzys ‘ : . 16,500! “26.40 Braci | “S18 oulder 05x40 mm “60 Kebaj 4484 Dishes, 8. C. P. porcelain, shallow form, with 90x55 mm “ 1.10 Esbjr SPOUb....-.. sees eeeeees 45 ml 26 Erasb 4516 _do., but with knob on cover... .110x70 mm “ 1.20 Esefy 60m! * 32 Erawt | 4529 Dish, aluminum, milk analysis... 24in. “ 24 Esdez 95 ml 48 Erazn Bin, “ 30 Esdkn oo : rt be 34 in. “ 40 Esdry 200 ml * 10 Erbot 4in. “ A8 Esdyk 350ml “92 Brhu | ony = oir, with cover SO mm “ AB Buenf 550ml“ = 1.14 Break Se Rees eee 600 ml “ 1.22 Ercec 70 mm « 60 Esewn 4486 Dishes, Coors porcelain, used in 89 mm “ 10 Esezh milk analysis............. 13 ml “ 30 Erdit 90 mm “ 85 Esfhr 25ml A2 Erdml 4522 « - « — witheoverandknob 2in. “ 45 Esgli 45 ml 48 Erdpe 4524 Dish, enamelware.............. 434x214 in, “. 60 Eshru 4487 Dish, porcelain, with heavy welted 4525 ff Aneaneralne) alundum RA-84 45gin. “ 1.50 Esiki rim, capacity 24 liters. .... 600 mm “ 30.00 Ereku 984 in. “ 3.00 Esind 4489 do, but ‘deep form, 25 liters.... 430mm“ 30.00 Erewp _ :123gin. & 6.00 Esusr 4490 Dish, ” Coors porcelain, deep form, ‘ 4526 = do., but circular....... eee Diam. 234 in. < 50 Esyma with long spout; 3250 ml, diam. 320mm“ 11.70 Enfiu 4527 Dish, iron, porcelain lined, with a : 4494 Dishes, opaquesilica, round bottom 2in. “ 1.35 Ergiq handles..............54 1 qt. 1.15 Eskik 234 in. “ 1.50 Erglk igal. “ 2.60 Esknz ‘ 34 in. “ 1.65 Ergsv 3 gal. “ 5.60 Eskul “B%in. “215 Ergal =| 4528 = Lead.........-. eee eee Zin. “ 10 Eslvi 44 in. “ 2.50 Erhbd 244 in. “ 15 Esmay 53¢in. “ 6.15 Erhip 3in. “ 18 Esmfo : 5% in. “ 6.35 Erhpa a : = ening F jlica...... 2in. “ 2.80 Erihg in. ‘ : smuj see Shee 2agin. © = 4.70 Erili gin.“ 60 Esndr 314 in. “ 6.90 Eripz 4530 “Nickel, spherical shape. .... 23% in. “ 1.30 Esobu 3%in. “ cen Erist aan “ ca Hes i ilica, flat bottom 2!4in. “ 1.50 Erjoa in. “ 10 Esoig eS” Desks opus aces ein 165 Brjuo | 4532 ~~ ‘fiabbottomstraightsides 2in.“ 1.08 Hapan 33g in. “ 1.85 Erjze - 284in. “ 1.45 Espif 4% in. “ 2.50 Erkey ve a zi Hanes ilica...... Yin. “ 3.15 Erlabd in. “ 8p at do,, but transparent siliea Bo, in. “ 4.70 Erlif 4534 “ Silver, 50 mm, Ap. weight = grams gram a ee 4498 Dishes, opaque silica, shallow flat Ag ‘a a Sa a a ety : uv fee > form, without lip......... 13g in. “ 85 Ermdu ye 6195 paras # 4 EB y 134 in. “ .85 Ermgo 90 mm, Ee - grams 3 STUe in. “ 1.15 Ermle 100 mm, 175 grams 14 Essdm auin. * 1.15 Ermsp 125mm, “320 grams “14 Esshe te 4536 TIN Toil seas waco oaaeed ates 234x8Zin. 100 2.00 Esien 23 in. 1.35 Ermyd 1 a a 26xl7sin. “ 3.50 Estlv 234 in. 1.65 Erner ee 4500 -do., but transparent silica...... 13g in, “ 2.50 Ernae aarein #00 Bemse " P . 134 in. “ 2.80 Eroay 4538 “ Weighing, aluminum, with 2in. “ 3.15 Eroeg handleandcounterpoise.. 10mlea. 3.15 Esujy 27 A A R T H U R H. T H O M A Ss Cc O M P N iy: Cat. Code | Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 4538 Dish, weighing, aluminum, with 4624 Scissors, dissecting, 115 mm........ Straight ea. $0.75 Eukaw handle and counterpoise 20mlea. $3.24 Esunp Curved edge “ 90 Eukeo 30 ml “ 3.50 Esurh Curved flat “ 90 Eukig 4540 “weighing, aluminum, deep 4625 Scissors, dissecting, lock joint, fine form, with short spout ......... “ 5.40 Esvys points, 115mm......... Straight “ 1.50 Eula» 4541 do., but with long spout............. “ 5.40 Esran Curved edge “ 2.00 Eulen Curved flat “‘ 2.25 Euljd ‘ 4626 Dissecting, student...... 115 mm “ A0 Eumbs Q DISSECTING INS eS 4627 do., but better quality......... 115mm “ 60 Eumor 4550 Blowpipe, nickeled metal. .. . 5in. AS Esylq 4628 do., screw joint, 115mm. Sharp points.. ‘“ 15 Eunel 4552 = Artery forceps, bent form................. < 50 Eszuw One blunt point “ 15 Eunkf 4553 do., but straight form.................. 50 Etako 4629 do., aseptic lock joint, one sharp 4554 Bone cutting forceps............ 200mm “ 2.60 Etazj and one blunt point....... 105 mm “ 1.25 Eunve 225 mm “ 3.40 Etbir 115mm “ 1.50 Funzu 4555 1 we OO Mere ares wer SLL TAM 1.00 Eicik 125 mm “ 1.75 Euoco 4558 Dissecting Forceps, straight...... 95 mm “ 25 Etdne 4630 do., screw joint, heavy, one sharp 4559 f “ourved....... 120mm “ 30 Eteio and one blunt point....... 125 mm “ -10 Euogl 4560 ui ee | DIUM tise pate 115 mm “ 15 Eteon 140 mm “ 90 Euolf 4561 . “straight. . 115mm “ 50 Etfoa 175 mm “ 1.10 Euowz 4562 a “eurved....... 120 mm e 50 Etgoz 4631 do., aseptic lock joint, heavy, 4564 is “ straight...... 100 mm " 50 Bthoy both blades blunt......... 140mm “1.75 Euplo 4565 i “eurved....... 110 mm “ 50 Etifq 4632 Scissors, Coronary artery, probe point...... “ 2.00 Eugei 4566 as “ straight-heavy 105 mm © AS Etiul 4634 “ “Invertebrate........ Blades 10 mm “ 4.00 Euger 115 mm © 50 Etiyd 4636 Section lifter, nickeled.......... 100x18 mm “ .20 Eurno 130 mm * 60 Etjer 4637 «“" ebony handle, 2 blades. ...... is .70 Eusbm ; 145 mm * 10 Etjld 4638 ff ne * © Pbladew cca A5 Eusuz 4567 “ straightheavy 125 mm “ 50 Etkov 4639 “ “ “ eee 20 mm “ ‘A5 Eutre 4568 uf “—curvedheavy. 125mm “ 50 Etlui 4640 “ “ “ Coe ee 35 mm “ 55 Euluy 4574 Hooks and chains........................ = 25 Eimmy | 4641 “ “ perforated......... 18 mm “ 55 Euuks 4576 Double hooks. ge Sree aoe eR SL 25 Einug 4644 Seeker, one curved and one pointed end.... “ 50 Euuyp 4578 Knife, brain............... .. 185 mm “ 1.60 Etoly 4645 ERAN TAI forties eh he ee eae “ 35 Eure 4580 “Cartilage. ...........-. . 45 mm B 40 Etozv 4646 Shears, cartilage, nickeled........ 230 mm “ 2.50 Euwyn ° 4581 i we UNGAVn ca snag, 2 70 mm ss 90 Etgas 4648 Tenaculum, ebony handle........ 160 mm “ 30 Eursy 90mm “1.10 Etgie 4649 « “all steel............ 160 mm “ AO Euymk 4582 “ Virchow. oo... 2... - $gin 1.50 Eisbo 4652 Dissecting instrument case....... Type A “ AS Euzbf 4584 Bone saw, detachable blade... ... 200 mm “ 3.00 Ettap Type B “ 50 Euzht 4590 Needles, dissecting, straight and TypeD “ 4.00 Euzmj sharp................0005 135 mm “ AO Etiua 4654 Dissecting instrument set, in case.......... set 1.75 Evaae 4591 do., but curved and sharp...... 130 mm “ AO Etuku 4656 “ “ Lee Rt er “ 2.10 Evand 4592 do., but curved and blunt...... 130 mm “ AO Etvef 4658 “ “ (ae aa eR “ 3.30 Evazf 4593 do., but half spear shaped...... 130 mm “ 40 Etral 4660 “ “ KO HEISE oe Sy ae “ 14.00 Ecbru 4594 do., but spear shaped.......... 125mm “ 40 Etyjs 4595 do., but harpoon shaped....... 145 mm “ 60 Etzeb 4670 DISTILLING APPARATUS, Stokes, 4596 do., but hook shaped.......... 145 mm “ 40 Euaig gas heating......... No. 0, Mgal.ea. 25.00 Eveki 4597 Needle, dissecting, straight, in No. 00, 24 gal. “ 27.00 Evend cedar wood handle................. doz. A0 Euawn No. 000, 234 gal. “ 60.00. Evert 4598 do. bub bent: ccc. severe oregon 30 Eubmh | 4672 do., but steam heated... No. 00, Igal. “ 39.00 Evdna 4606 Needle holder, bone, with needle.. 85 mm ea 12 Euboe No.000, 3gal. “ 15.00 Eodrs 110 mm “ 5 Eubsu 4674 do., U.S. Army Medical Dept. model 1gal. “ 31.00 Evego 4610 Needles, only, for No. 4606...... Style A doz. -10 Eucio 4676 Distilling apparatus, Stokes, for Style B “ 40 Eucnd gasoline heating. .... No. 0, gal. “ 37.50 Eveul Style C “ 60 Eucst 4678 do., but steam heated, large StyleD “ 1.00 Eucun MOdEl ee eens No. 1, 5gal. “ 159.00 Eofow 4612 Oil stone, for scalpels............ 3 in. ea. 60 Hudne ran No. 2, 10gal. “ 200.00 Enfso 4616 Scalpels, dissecting, Qual.I...... Style A “ 80 Euecy 4680 Distilling apparatus, Barnstead, Style B “ 80 Eueim for illuminating gas....... l gal. “ 60.50 Evgov Style C “ 80 Euelg egal.“ 75.00 Hugsn StyleD “ 80 Eueoz 2 gal. “ 96.80 Evhax Style E “ 80 Euesr t h Segal. “ 165.00 Evhep Style F “ 80 Euevl 4682 do., but with adjustable burner StyleG “ 80 Eueyf for coal, natural or gasoline pears 7 oo... = 18 mm * 80 E. BAS capi ds atilee ese iiee © 1 gal. “ . vhya 4617 do., but regular shapes see 5 Weal. THEO Botka 32 mm “ 80 Eufzg 2 gal. “ 99.30 Evieo 38 mm “ 80 Eugby : 5 gal. . 167.50 Eviig 45 mm “ ‘80 Euggo 4684 do., but electric, 110 volt...... 1 gal. i 75.90 Eviwd 50 mm “ 80 Eugik ; 2 gal. 121.00 Evjao 4618 dij, but all steal poe ees 2a 25mm “ 90 Eugin 4685 do., but electric, 220 volt...... 1 gal. - 75.90 Evjug 32 mm “ -90 Eugzb 4686 Heat : 2 gal. 121.00 Evkau 38 mm “ "90 Euher eating units for Barnstead Elec- decaf 90 Euhij tric stills, 110 volts ....... 1 gal. “ 6.50 Evlat i ; : Qeal.“ 9.00 Eulid 4620 do., Qual. II, black handle..... aa mm “ 25 Euhvi 4688 Distilling apparatus, Barnstead, for mae 25 Euhza steam heatin, 1 gal. “ 72.60 Evmja 38 mm “ 25 Euieg Bick hctieer ne sents \g Dae Gee ij “ . gal. 04.50 Evmop se 25 Euigm Tegal. “ 154.00 EZomar 4622 do., steel, corrugated handle. . Vins" 45 Euivh : : 14 in. “ AS Euiyb 4690 Distilling apparatus, copper...... 3 gal. “ 43.25 Evodk 1gin. “ AS Eujep Segal.“ 56.00 Evohe 134 in. “ A5 Eujih 4692 - 3 Salleron ............. i 13.60 Evoxv 28 A R T 4H U R H. T H O M A _ S Cc O M P A N_ Y Cat. Code Cat. Code No. Description Size Unit Price Word |’ No. Description Size Unit Price Word 4694 Distilling apparatus, Regnault......... ea. $54.50 Hvpse 4772, ELECTROLYTIC Support, with ring and 4696 copper...... 4% gal. “ 43.25 Evgol CIM: acing odes ayes aes ea. $3.75 Exkms lgal. “ = 48.00 Evguz 4773 do., but with two clamps, no ring........ ee 5.00 Exlua 4698 s “automatic... 3qt. “ 45.00 Husam | 4774 do., with one clamp and separate ring... . “ 3.75 Exnan 4700 u 7 nf copper retort 4776 Switchboard, Electrolytic........ = volt “ “115.00 Exodg with zinc condenser....... Ygal. “ 15.25 Evsyp 4777 do., for 110 Volt d.C......00.cceeeeseuee 115.00 Exosb 1 gal. “ 19.25 Evich 4778 do., for 220 volt, d.¢.............. ee eee “115.00 Export 2gal.‘“ 24.80 Eutkr 4780 Rotating anode and stirring device, for 110 3 gal. “ or Evtoc aii F VOlt OG. cisciiins viaaies yeee eee ; ae oe Segal.“ 38.50 -Evisa . o., but 110 volt, 60 cycle, a.c........... 2 . cso 4702 Distilling apparatus, oil, for steam : 4784 Rotating anode apparatus, Cenco, 110 volt d. c. 34.00 Extmj heating.................. Yegal.““ 20.00 Evujs 4785 do., but 110 volt, 60 cycle, a. c.. 34.00 Exube 1 gal. “ 32.00 Evuoh 4786 Electrolytic outfit, Braun, for 110 eras 2 gal. “ 48.00 Evutz VOM ACs soakewwigae es 2 units ea. A cugz Segal.“ 56.00 Hvuwr 4units “ 217.00 Exuur Segal.“ 64.00 Eouzl 6 units “ 244.00 Exusl 4704 Distilling apparatus for determina- tion of ammonia in water’.......... e 8.50 Evosy 4705 Distilling apparatus, Vacuum, Pyrex....... te 8.50 Evrah ELECTROMOTIVE FORCE 4706 Tube, only, with sideneck................ “ 1.00 Evxzi Ai? Dadiliing (ovarstus, vacuum with "| 4790 Potentiometer, L. GN. Type “275,00 Exwae waterbath and tripod... xn 18.50 Hoynf 4792 “Simplified, i & N,, with ex- : . 4708 _ do., but with copper condenser,ete........ “ 40.00 Evzhr tension coils and cut-out switch...... ‘90.00 Eaxin. 4709 Copper condenser, only..................: “ 21.75 Evzzg 4793 do., but without extension coils and cut-out a 4710 Glass reservoir, with gauge, etc............ “15.00 Ewanb SWitch..... 0.000... eee eee eee 80.00 Euan 4711 Distilling apparatus, Knorr i i Seca Sages “12.00 Ewbab 4796 Galvanometer, L. & N. enclosed lamp and es 5.00 E. 4712 Kendall, silica... “ 55.00 Ewbum BCAlC. eee eee ees : 2 le 4713 Retort, only, of No. 4712; silica. . é 10.00 Eweme 4797 Lamp resistance, for above, for 110 volt.. . : oe eae 4714 Connecting tube, only, ‘at. No. 4712... “ 27.50 Ewdny 4798 do., but for 220 volt..................05 : 'yaeg 4715 Flask, only, trans. silica......... “500ml “~~ «17.50 Eweeq 4799 Incandescent lamp, only......... 4 volt 7 at a 4716 Distilling tube, Hempel.................- “ 2.25 Ewerp 4800 Portable d’Arsonval galvanometer, L. & N.. 8. y bi 4117 = “Pyrex glass... 12x1in. “ 1.00 Ewfih 4804 Capill “ “ “ eg . pillary electrometer, Eppley............ 80.00 Eychu . ee. Se ee Plain ‘20 Ewghi | 4805 Glass parts only, of No. 4804.00.02... “12.00 Byer pie “ “ Mee ah “ "45 tel 4806 Reading microscope, only................. «24.15 Eydnu 4720 RAGS 200 wuem | 4807 Capillary electrometer tube, Ostwald. ce 1.50 Eyedo 4721 _ Distilling tubes, Glinsky.. hei & Rees uh a ea. 7 re 4808 “ Luther. la 6.00 Eyerl “ , : 4820 Standard cell, Weston model 4............. “25.00 Eyfel “ “ : OEE Se 4821 do., but with Bu. of Standards certificate. “ 29.50 Eyfwa 4723 LeBel-Henninger 3bulb 1.75 Ewjst 4822 Standard cell, Eppl “ 15.00 Eygmu “ “ “ “ 4bulb “ 250 Ewknr : PPlOY....-. ee ee eee Leen a e yg’ ne bulb 250 Euinr | 4823 do. but with Bu. of Standards certificate. “18.00 Bythd pis i Oboe SREY 12 a. ei 175 Eumei 4826 Standard cell, Eppley student, mounted.... “ ae Hylan a nt Passe hig . 4827 do., but unmounted..............-.00-- ue A yin 4728 - “ Young.........- 15 discs“ os ass 4828 Standard cell vessel, H-form, unfilled....... e 4.10 Eyjel 1 20 dises it : wnt 4829 do., but improved design............-..5 ee 5.30 Eyjoy . i “ @ 4bulb 2.30 Ewoh A130 ete Teer ees i 5 fens 4832 PortableHydrogen-ion Potentiometer,L. &N. “ = 150.00 Eykmg 12bulb 6.25 Ewol bi : os 4834 Calomel electrode vessel, platinum spiral.... “ 4.00 Eylhz 4731 Distilling receiver, Hora Patecens 250 ml ae Fools 4836 ee! eit oanatriGHOUS scccciy “ 8.10 Eyluy 4732000 8 EE Bri eac oe weane ex ates : a WPYyd 4838 “ “ vessel, Kelley, without — 4735 “ Adapter.....-..-...--; iipe Slt Buyer metallic electrode ................+: = 8.00 Eymks 4736 Drying ee ace eho me Burge | 4838 Platinum electrode, for ne 4898. 200 Epmen Bees vegeta Eaklnee 4840 Calome e ectrode vessel, Pauli............ ee 00 Eynot 4737 ee Tube, Liebig. cape e teen rene tees eees S -40 Ewsgy 4841 Roberts.......... “ 3.00 Eyocg fe io tO Sand wns oaseens es - 9.25 Eyout 10 DYE BATH, Matthews, dry at, wth 4 por | Re. (Se yok ee «$80 Hom Jain beakers. ......-...-0000-0e ee “i 20 Ewti “ “ “ i 4741 do., but with 4 Pyrex glass beakers....... “28.80 Ewubg si ae eed . 5.00 Eyghu 4742 do., but without beakergs...........00005 Mt 26.40 Ewuof 4848 “ “c “ modified ‘Ostwald “ 5.40 Eyrez 4744 Dye Bath, re water, with . 28.80 Envoe 4850 «electrode vessel, comparison group ‘nz porcelain beakers....-....-- +--+ ++ “ : : OL Uhre 8 sats nc wissen wad esd hws ee 2 yrat 4745 do., but: with 4 Pyrex glass beakers ...... ie 26.40 Ewiyj | 4gso Hydrogen’electrode, Hildebrand........... “ 5.75 Eysnf 4746 do., but without beakers.............--- 24.00 Ewyca 4853 Adapter, for use with No. 4852............ “ ‘75 Eytkl 4748 Dye Bath, Matthews, for glycerine or CaCl, 4854 Hydrogen electrode vessel, Clark........... fe 9.00 Eytyi with 4 porcelain beakers............. yy 52.80 Ewyge | 4955 Platinum electrode, for No. 4854........... “4.50 Byuob 4749 do., but with 4 Pyrex glass beakers. . hi ara ee 4858 Hydrogen electrode, McClendon........... “« 12.00 Eyveo 4750 do., but without beakers..............-: 00 Exago 4860 fh Bae “ 4.85 Eyvig 4154 Dye Bath, rectangular, water, with 6 porcelain : Z 4862 a “Bailey... 0... see. “ 3.78 Eywoz beakers tly cidhdubuhtes Suibs eedaenier Soe. Bie phe re ES 3 ees es 4864 “ ‘“ Vessel, imp. Ostwald... “ 6.25 Eyxoy 4755 do., but with 6 Pyrex glass beakers. . : a 0 En. Z 4865 Platinum electrode for No. 4864 o 4.00 Eyyhm 4756 —_do., but without beakers............-..- 00 Exes 4866 Connecting vessel, Clark...............+-. at 7.80 Eyyzb 4758 Dye Bath, rectangular, for glycerine or CaCl, a apie ae 4867 “ “for liquid junction...... “« 5.10 Evzso with 6 porcelain beakers........-... “42420 ae 4868 Electrode vessel, on glass foot............. ea. 3.50 Ezahi 4759 —_—_dg., but with 6 Pyrex glass beakers....... a har Eafe 4869 ‘” without glass foot......... « 1.50 Ezauk 4760 do., but without beakers..........-...-- 00 Exfos 4870 Metallic electrode, platinum, for Nos. 4868 sup ee aNd 4869 va02 + osuearesaguale gba eo : . 2bg0 : 4871 ee without electrode. .. oe x i ce « §2.75 Exgysx 4872 Metallicelectrode, platinum, for No. 4871.... “ A zdoq i165 Same oe “12.00 Exhzu 4873 Electrode vessel, without electrode......... tf 6.75 Ezeek 4766 i Juerst patent. iad one “60.00 Eainr 4874 Metallic electrode, platinum, for No. 4873... “ 4.00 Ezesh A767 “ Thermometer, Juerst... “ 17.50 Eajej 4876 Glass tube, Pyrex, bent for salt bridge ..... . 5S Ezfue 29 A R T H U R H. T H O M A S Cc oO M P N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 4878 Combined support and shaker, L. & N., for 4960 Extraction flask, Sy...... ees 250ml ea. $1.00 Faown 110 volt, 60 cycle, a.c....... _ ea. $75.00 Ezgpl 350 ml “ 1.15 Faozh 4879 do., for 110 volt, d. c. ies 75.00 Ezheh 4962 a “ Nonsol glass.... 120ml “ 9 Fapqy 4880 Hydrogen-ion calculator, L.&N.. a -50 Ezhys 195 ml “ 23 Fapvo 4882 Type K Potentiometer Outfit, for 110 volt, 60 ee “ 2 fe cycle, a.c.. “471.60 Ezi . : 4883 _do., but 110 volt, d.c.. ee UE a || a le NI a ace 4886 Hildebrand hydrogen-ion outfit. . coe “99,25 Ezkei BOM O NG ace tae SaaS 50x19 mm 3.15 ae 2 4888 Simplified potentionieter outfit. . .... “179.65 Ezkyp 90x19 mm “ 3.15 Ford 4889 do., but without extension coils and cut-out “ , J 7 80x22 mm 3.15 Farmf switch on Potentiometer........... 169.65 Ezlzm 60x26 mm “ 3.15 Far 4890 — Potentiometer, Bovie, L. & N., 110 volt.... “ 250.00 Ezmzl 80 t: ; PY we x25 mm 3.55 Farum 4891 do., but for 220 volt..............0..... 250.00 Eznxo 100 “ x25 mm 4.40 Farze 4892 Semi- “multiple logarithmic co-ordinate paper, 80x33 mm “ 3.55 Fase numbered 0 to 20...... ; .100 3.00 Ezoko : “ y : 94x33 mm 4.40 Fasim 4893 do., but numbered 0 to 10. ea. 3.00 Ezozj “ o 118x33 mm 6.00 Faslg 4894 Hydrogen- calomel cell, Bovie, complete . 33.00 Ezpus “ 4895 “Electrode vessel, Bovie....... .. ; 3.00 Ezgod 4965 das hut double: thick ee ei “ ee nee 4896 Calomel electrode vessel, Bovie. is 8.00 Ezsae Bee ecco SUES uaa: 90x19 mm “ 5.28 Faina 4897 Glass cone, only, for No. 4895..... a 2.00 Eztev 80x22 “ ; : i mm 5.28 Fatrs 4898 Plate glass disc, for top of cone au 1.00 Ezuba “ i 60x26 mm 5.28 Fatum 4899 Support, only, for No. 4894............... 20.00 Ezusr 80x25 mm “ 5.92 Fatye 4900 Hydrogen-i -ion outfit, Bovie.. 110 volt “ = 283.00 Ezvlf 100x253 mm “ 7.36 Fae 4901 “62... 220volt “ — 283.00 Ezwme “ : 80x33 mm 5.92 Faugo 4906 Titration outfit for comparison with standard 94x33 mm “ 736 Fauii buffer mixtures, for 110 volt. . “116.65 Ezruk “ 4 J i 118x33 mm 10.00 Faunz 4907 do., but for 220 gel ee 116.65 Ezyma “ 123x43 mm 11.84 Fausp 4910 Roberts electrometric titration unit, L. & N., : : 4966 Extraction thimbles, alundum, without glassware................. 60.00 Ezzet RA-84 dense 32x51 mm ea 75 Favld 4911 Titration head, Hostetter & Roberts, a Pos COURS race 35x55 mm 30 Bavoi Haskt aa aca dereseniers 50 ml “ 8.00 Ezzro 26x60 mm “ ‘60 Favso do., with flask................ 500 ml “ 9.00 Ezzui “ e . : 25x70 mm 10 Favvi 4912 do., but without calomel electrode 30x8 “ a P x80 mm 15 Favza vessel; for flask........... 50 ml 5.00 Faaje “ ae 19x90 mm 60 Fawds do., for flask... 0.000.020... . §00 ml 6.00 Faant 34x100 mm “ 90 Fawgm 4914 Hostetter & Roberts electrometric titration 39x127 mm “ ‘90 Fawke OUD beri le etree 5 pawn dames hee 80.28 Fabat 45x127 mm “ 1.00 Fawnz 4920 KELLEY ELECTROMETRIC TITRA- 4967 do., but RA-360 medium...... .32x51 mm - 15 Faxdr TION OUTFIT, for 110 d.c., or 110, 35x55 mm i 80 Fazxgl OO OYG te Bosca cacen ewes vara “250.00 Fabsi zoxodamat AO ata 4922 do., but for 220 volt, 60 cycle, a.c........ “© 265.00 Facky POETS Th Faxrs 4923 _do., but for 220 volt, d. ¢.. vse. © 250.00 Fadhd 2 eee 75 Faxwe 4924 Glass stirrer, without metal holder. as 1.70 Fadyu 19x90 mm © 60 Faxzy 4929 HSpitaki belts, secven ce ties senate ae ael ue 15 Faenp 34x100 Le -90 Fayes 4926 Moving system, in interchangeable mount... “ 30.00 Fafhd pare eee an ae x127 m 00 Fayig 4938 Embedding boxes, paraffine. . Small “ 90 Fafys 4968 do., but RA-98 coarse. ........ 32x51 mm “ 15 Fayuh Medium “ 90 Fagdi 35x55 mm “ 80 Fayyz Large “ 90 Fagha 26x60 mm ‘“ 60 Fazen 4940 Emery cloth, 9x11 inch sheets. ... Fine doz. 1.15 Fahan 25x70 mm ‘‘ 10 Fazlz Medium ‘“ 1.25 Fahhz 30x80 mm “ 15 Fazgo Coarse “‘ 1.40 Fakir 19x90 mm ‘‘ 60 Fazti 4941 “paper, 9x11 inch sheets... . Fine “ 40 Faiam 34x100 mm “‘ 90 Feaam Medium ‘“‘ AS Faidg 32x127 mm “ 90 Feadg Coarse ‘ 60 Fathy 45x127 mm “ 1.00 Feahy 4944 Eudiometers, Bunsen, with plati- 4970 Extraction thimble, alundum RA- num electrodes. . . 50 ml ea. 3.65 Faiuz 98 coarse, Oberfell,...... 50x165 mm “ 1.75 Feazr 100ml “ 4.00 Faizn 4971 do., but impregnated with Bakelite....... ‘ 2.25 Febnk 4946 s Mitscherlich. . 50 ml “ 4.00 Fajsa 4974 Extraction thimbles, glass....... 25x80 mm “‘ 30 Fechi 100 ml ‘ 4.75 Fajvu 33x80 mm ‘ 15. Fecec 4948 “ Ure re. steels aeetess 50m] ‘ 3.50 Faknj 43x123 mm “ 1.00 Feciu 100ml ‘ 3.75 Fakuv 4975 Extraction tube, Pyrex glass,Soxhlet 12in. “ 5.00 Fedhv 4976 Extraction tube, Soxhlet.........30x70 mm “ 1.50 Fedzk 4950 EXTRACTION FLASK, Knorr, 38x75 mm “ 2.00 Feece with hole in neck . A 100 ml “‘ 50 Falit 50x113 mm “ 2.40 Feehu 4952 do., but with two holes........ 100ml “ 10 Falym 4977 “ “ Southern Cotton Oil Co... “ 1.60 Feeyl 4955 Extraction flask, Pyrex, flat bot- 4978 uc “ Smalley.......2...0004.. se 1.75 Fefus tom, wide neck, vial mouth . 50 ml “ 16 Fammk | 4980 “ OP STR OPT vor vacates saa tee “ .10 Fegjo 100 ml “ 18 Famut |, 4982 x “ _“ Tmproved form...... “ 60 Fegzh 150 ml -19 Famyl | 4984 “ “ Butt, Pyrex.... 130 mm “ 60 Fehpa 250 ml “ 20 Fancd 500 ml “‘ 29 Fanir 4986 Extraction apparatus, Soxhlet.... 30 mm “ 4.60 Feiew 750 ml “ 36 Fanmj 38 mm “ 5.00 Feihg 1000 ml “ 04 Fanga 50 mm “ 5.80 Feili 2000 ml “ 98 Fanus 4987 do., with ground joints........ 30 mm “ 7.00 Feixj 3000 ml “ 1.40 Fanzm 38 mm “ 8.00 Fejad 4960 Extraction flask, Sy............. 100 ml ‘‘ 60 Faolk 50 mm “ 9.00 Fejhp 150ml “ 80 Faood 4988 do., with Hopkins condenser.... 30mm “ 8.50 Fejze 200 ml ‘ 90 Faosv 38 mm “ 9.50 Fekcy 30 31 A R TT H U R H. T H O M A _S Cc O M P A N YY Cat. Code Cat. Code No. Description . Size Unit Price Word No. Description Size Unit Price Word 4988 Extraction apparatus, with _ ; 5083 Files, triangular, slim taper/...... 3in ea. $0.10 Fitiv condensor.. ... 50mm ea. $10.50 Fekim .4in, “ 12 Fitmn 4989 do., with Erlenmeyer flask. .... 30 mm : 8.75 Felbz 5in. “ 12 Fitge & mm i ian a 6in. . 12 Fitty mm 79 Felhn Sin. 20 Fits 4990 Extraction apparatus, with Knorr flask... .. ; 8.50 Felvk 5084 “ “double taper. . . Sin. “ 35 Finn teat : : Rie id 2 gan . Le ne 5085 “half round, rasp........... Sin. “ 52 Fivit . : . orm...... is A ‘en 10in. “ -70 Fivml eS ee eee - ee a es les : ee a 5088 File handle, of wood....................4. € 10 Fiwlm | , improved..... 15 Feogm 4 pet ae bub ee in neal of flask. . ees re ee 5090 FILTER CYLINDERS, Mandler 10x2in. “ 4.00 Fiary . mdenser, norr extraction apparatus... “ s ep 8xlin. “ 3.00 Fi 5001 Nickel dise, for Knorr extraction apparatus. “ 30 ae 5xl in, s ‘2.50 Finet S03 Platinum dis, with rod, for No. d006.1 «= pen een “118 Fig in ¢, wi i . 4996...... 7 : ; ex5¢ in, 1S Fiy 5004 : : without rod, for No. 4996... Fesdo 5091 do., No. la, with porcelain head- F i 5005 Wire spring, nickel, for No. 4996.......... “ 15 Festh piece and nipple.......... 10x2in. “ 3.50 Fizaf 5008 Extraction apparatus, tomato pulp......... af 4.20 Fetpo 5092. _ do., No. 1-P..............0055 10x2in. “ 4.00 Fizsu 5009 Condenser, only, for No. 5008............. - 1.80 Feufi 5094 = Filter cylinder, Allen porcelain... 10x2 in. “ 6.00 Flagm 5010 Cylinder, only, for No. 5008............... s 1.80 Feutf 5100 ‘Filter cylinder, Berkefeld “W” fine, 5011 Thimble, only for No. 5008............... a 60 Fevmt with metallic headpiece.... 10x2in. “ 4.00 Flail 5012 Extraction apparatus, Thorn... .180x30 mm “ 3.50 Fewei 8xlin. “ 3.00 Flawf ies ate - 240x40 mm “ 2 eee 5xlin. “ 2.50 Fleau e OTs oe eres sciys s F exap 214x54in. “ 1.25 Fledo 5015 Condenser, metallic, only, for No. 5014... uf 2.25 Fecua ae a 1.25 Flegi a Cae piste a ee patos tf = fore 5101 do., but “N” medium... 10x2in. “ 4.00 Flevd ondenser, metallic, only, for No. 5016... .. i . ez 8xlin. “ 3.00 Flezv 5018 Syphon tube, glass, for No. 5016........... es 80 Fezwu 5xlin. “ 2.50 Flhib Ey Extraction apparatus, wile, pe anes ; a thos 234x54in. “ a Fliag = iley-Richardson . . es eae 2xlin. “ 25 Flidk a Ginie 2 eee Nos, ae sa 5021. “ “e pire 5102 do., but “V” coarse........... 10x2in. “ 4.00 Flirh ler, glass, for Nos. an owes % ‘ eq 8xlin. “ 3.00 Flivz 5026 Extraction apparatus, Teas......:........ “32.00 Fhirp 5xlin. “ 2.50 Fliar 5027 is Yocum............. i 35.20 Fhobg 234x54 in. “ 1.25 Flocg 5028 8 *s RGGd nce 4 cayenne sats 43.20 Fhopn 2xlin. “ 1.25 Flofa 5029 € s Oberfell “61.50 Fhrom 5105 Glass filter mantles, Pyrex...... 1334x434 in. “ 1.75 Floxp 5036 Extraction support, gas heating............ a 8.85 Fhulg € 11x234 in. “ 1.25 Fluae 5037 electric...... 110 volts “ 13.00 Fhyat 554x234 in. “ 1.00 Fluca oa a to or TeNr volts “44.75 Fhynh 2beelse in, “ 30 Fiua actions.............-- vo: E x14 in 4 uio 5040 do., but for 6 extractions....... 110 volts “ a Fiaew 5110 ‘Filter cylinder, Chamberland- Pasteur “B” - 5041 do., with 6 hot plates.......... 110 volts “ = 112.00 Fiast 200x25 mm “ 2.00 Fluwl 5042 Extraction support and water bath, gas, for 5111 do., but fineness “F”......... 200x25 mm “ 2.50 Flyle ppo! 6 extractions..............5.0.0005 “28.75 Fiblh 5112 ‘Filter, unglazed porcelain....... 115x20 mm “ .96 Foaar 5043 Extraction support, Ross, electric, 110 volt.. “ 40.00 Ficha 5113 “Balloon, unglazed....... 200x125 mm ‘“ 1.98 Foapm 5046 Extraction apparatus, Bailey-Walker, with 5114 “Porous, unglazed........ 130x28 mm “ 50 Fobdk glass syphon; without hot plate...... 3 Da Seas 5116 clase and Ampoule filling apparatus, com- - 5047 —do., but with Gooch crucible............ et 90 Fidoy DIGG: oc eeviegs Haknsres ahi sy baw ta tf 5.00 Fobsf 5048 Condenser, metallic, for No. 5046.......... sf 4.40 Fiees 5117 do., but without stopper, filter or mantle. ‘‘ 23.00 Foeno - 5049 Syphon cup, glass, for No. 5046............ a 1.00 rat 5118 Filter Seman, Chamberland-Pasteur, com- : sgn 5050 Extraction flask, for No. 5046............. ve 1.00 Fi DIG 5 ec ach ascchenect-ceideatvan eosin SR 00 Foddi 5052 Extraction apparatus, revolving, ; 5119 do., but without hand pump............ “80.00 Fodzxt electric, for 6 extractions. . . 110 volt “ 70.00 Fifye 5120 Filter apparatus, pressure........ lgal. “ 60.00 Foekt 24% gal.“ 75.00 Foenm 2 ‘4gal.“ 95.00 Foere 5060 Fermentation TUBE, may aduated, Solace 5124 Filter apparatus, Hill, for — serena “154.75 Fofhy OM TOOE: & aipesieice eersenreeeind + asters 7 35 Figsn 5125 Rubber bag, only, for No. 5124. . Lliter “ 4.55 Fofyp 5061 do., without foot..............26.2seee- o 20 Fihhj 5126 HS eo 150ml “ 2.35 Fogot 5062 do., on foot; graduated. .............++- 5 eH a 5136 Filter cones, alundum RA-320 dense 15 ml “ 30 Fohde ae Fermonlation lab, A.P.H.A. standard..... a 0 Fijrm 35 ml “ _ Fohgy o., Without foot.........---.00eeere eee ‘ y 60 ml “ 85 Fohlo 5068 Fermentation tube, without bulb.......... ey i E a 250ml “ 1.50 Fohof oti are without foot... 7 8) rie ~—«| 5137 do, but RA-321 medium... 15ml “30 Foigr asometer scale, KTOSt.....------ erect - H “ ee 5072 Fermentation tube, Dunham.. . .150x16 mm 10 prs. a paw a “ S aed 5073 i 7 eho va. 425 Pinue 250ml“ 1.50 Foipe py 7 eee 12 tubes eae Te Fin | 5138. do, but RA-322 porous........ 15ml“ 30 Fojis ae : “ “ “ 10 se ene : : ct 250 Fioyt ou _ 2 eae Saber a Loy ml 85 Fojrz 5077 do., but sand blasted aluminum.......... 4.50 Fipgi 250ml “ - 150 Fonnn : in, “ 19 Figk 5139 Rubber gasket for filter cone..... 15 ml “ 05 Fokam 5080 Files, flat Lda dataset adh neal wie. es aeeEeNe aes a Pn ‘92 Fignt 35 ml “ 05 Follkc Sin. “ 22 Figet 250 ml “ -10 Folod 5081 “ d 4in. “ 15 Firlr 5142 Filter discs, alundum RA-225 Med. 34 in. “ 40 Fomfv POUUG:.. ce cdes Ree SSeS re 16 Firok ; ti lin. “ A5 Fomip Gin. “ 18 Firse 2in, “ 50 Fomlj Sin. * ‘18 Firwu 3in. “ 2 Fomoc 2 Sin. “ 35 Fisks 4in. “ 15 Fomsu 5082 © half round.............06+ 10mm te 45 Fisnl Sin. “ 1.00 Fomvo - - A R T H U R H. a H O M A Ss Cc O M PY °A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 5142 ‘Filter discs, alundum RA-225 Med. 6Gin.ea. $1.25 Fomzg 5178 Filter paper, Munktell No.2...... 55mm pack $0.32 Fuaip 7in. “ 1.50 Fondy 70 mm ‘ Al Fualj Sin. “ 1.75 Fongs 90 mm “ 63 Fuaoe 5143 do., but RA-98 porous......... 3qin. “ 40 Fonun 110 mm “ 82 Fuasu lin. “ AS Fonyh 125 mm “ 98 Fuavo 2in. “ 59 Foocz 150 mm “ 1.26 Fuayt 3in. “ 60 Fooft 185 mm “ 1.67 Fubbe 4in. “ .15 Fooin 5179 do., in sheets............... 480x480 mm quire 3.00 Fubro 5in. “ 1.00 Foomf ream 51.00 Fubup 6in. “ 1.25 Fooru 5200 Filter paper, Whatman No. 1..... 70mm pack = .20 Fuejl Tin. “ 1.50 Foowk 90 mm “ 24 Fuene Sin. “ 1.75 Fooze 110mm “ 28 Fucru 5146 ‘Filter dishes, alundum RA-84 dense 214 in. “ 90 Foprt 125 mm “ 37 Fucti 4in. “ 1.25 Fopvl 150 mm “ 51 Fudac 55¢in. “4 2.00 Foget 185 mm “ 71 Fudew 5147 —do., but RA-360 medium....... 2!4in. “ 90 Foque 240mm “1.25 Fudjk 4in. “ 1.25 Fores 270 mm “ 1.48 Fudme 55¢in. “ 2.00 Forhm 320 mm “ 2.30 Fudrt 5148 do., but RA-98 porous......... Qe in. “ 90 Forvj 5201 do., in sheets.............. 1814x2214in.100 4.45 Fuegp din, “ 1.25 Forzb ream 20.25 Fuekh 55¢in. “ 2.00 Foser 5202 Filter paper, Whatman No.2..... 70mmpack — .27 Fuezg 5149 Rubber gasket, for filter dish... .. 300 ml “ 50 Fosso 90 mm “ 34 Pufby 110 mm “ A2 Fuffq 5160 FILTER PAPER, American Standard 125mm “ 02 Fufik 75mm pack 17 :-Fotke 150 mm “ 74 Fufme 90 mm ‘ 19 Fotnz 185 mm “ 1.04 Fufqt 100 mm “ 21 Fotrp 240 mm “ 1.78 Fuful 110 mm “ 24 Fotuj 5203 do., in sheets.............. 1814x2214in. 100 6.85 Fugow 125 mm “ 26 Foubv ream 31.10 Fugso 150 mm “ 34 Fouep 5204 Filter paper, Whatman No. 4..... 55mmpack .27 Fuhgm 180 mm ‘ 44 Fouhj 70 mm “ 30 Fuhke 200 mm “‘ -56 Foulb 90 mm “ A0 Fuhnz 250 mm “ .18 Foups 110 mm “ 50 Fuhgr 330 mm “ 1.28 Foutk 125 mm “ 65 Fuhtl 380 mm “ 1.62 Fouze 150 mm “ 90 Fuhyb 450 mm “ 2.25 Fovaw 185 mm “ 1.30 Fuict 500 mm “ 2.85 Foufm 240 mm “ 2.22 Fuifn 600 mm “ 4.90 Fovje * 270 mm “ 2.70 Fuijf 5161 do., in sheets............... 480x480 mm 120 = 3.85 Fowbt 320 mm “ 4.10 Fuiow 480 14.00 Fouwf! 5206 Filter paper, Whatman No. 40... 55mm “ 1.10 Fujes 5164 ‘Filter paper, A.D. L............ 55mmbox 1.10 Fowve 70 mm “ 1.20 Fujhi 70 mm “ 1.20 Foxor 90 mm “ 1.70 Fujla 90 mm “ 1.70 Foxuf 110 mm “ 2.00 Fujot 110 mm “ 2.00 Foyat 125 mm “ 2.30 Fujsl 125 mm “ 2.30 Foydn 150 mm “ 2.70 Fukav 150 mm ‘“ 2.70 Foygh 185 mm “ 3.60 Fukfl 185 mm “ 3.60 Foyjb 5208 Filter paper, Whatman No. 41.... 90 mm “ 1.70 Fukza 5168 | “ Munktell No. 00.... 55mm pack 1.57 Forry 110 mm “ 2.00 Fuleq 70 mm “ 1.73 Fozco 125mm “ 2.30 Fulfk 90 mm “ 2.52 Fozfi 5210 a v ‘ No. 42... 55 mm “ 1.10 Fuluf 110 mm “ 3.15 Fozja 70 mm ‘ 1.20 Fulyzx 125 mm ‘“ 3.47 Foznr 90 mm “ 1.70 Fumbr 150 mm “ 3.94 Fozql 110 mm “ 2.00 Fumgh 185 mm “ 6.62 Fozyv 125 mm “ 2.30 Fumkz 5170 =‘ Filter paper, Munktell No. 0..... 55 mm “ 63 Fralp 150 mm ‘“ 2.70 Fumns 70 mm “ 85 Fraoi 185 mm “ 3.60 Fumrk 90 mm “ 1.32 Frasa 5212 Me o No. 43... 55mm “ 1.35 Funhe 110 mm “ 1.73 Fravu 70 mm “ 1.50 Funky 125 mm “ 1.98 Frayo 90 mm “ 2.20 Funop 150 mm “ 2.68 Frebf 110 mm “ 2.55 Funrj 185 mm “ 3.94 Freez 125 mm ‘“ 2.80 Funud 5171 do., in sheets............... 480x480 mm quire 7.50 Frery 150 mm “ 3.60 Funzt ream 135.00 Frevg 5214 ‘ i M No. 44... 70mm “ 1.50 Fuong 5172 Filter paper, Munktell No. OA 90 mm pack 2.52 Fridz 90 mm “ 2.20 Fuosg 110 mm “ 3.15 Frigr 110 mm “ 2.55 Fuova 125 mm “ 3.47 Frijl 125 mm “ 2.80 Fuozs 150 mm “ 3.94 Frinc 150 mm “ 3.60 Fupem 5174 “ “No. OB... 90 mm “ 1.51 Frobo 5216 weno See O No. 50... 90 mm “ 1.70 Fupyt 110 mm “ 1.98 Froou 110 mm “ 2.00 Fugel 125 mm “ 2.20 Frosm 125 mm “ 2.30 Fugno 150 mm “ 3.00 Frovg 150 mm “ 2.70 Fugrg 5176 = Filter paper, Munktell No. 1F... 55 mm “ 39 Fruib 185 mm “ 3.60 Fuqoy 70 mm ‘“ 50 Frumt 240 mm “ 6.10 Furao 90 mm “‘ 19 Fruri 400 mm “ 15.75 Furdi 110 mm “ 94 Fruuc 500 mm “ 20.85 Furha 125 mm “ 1.26 Fruyu 5218 Filter paper, Whatman No. 12, 150 mm “ 1.57 Frybl folded his. 2aen coeavecnn sare 125 mm “ 80 Furzp 185 mm ‘“ 2.36 Fryef 150 mm “ 1.00 Fusdh 5177 do., but sheets.............. 480x480 mm quire 3.60 Fryre 185 mm “ 1.20 Fuskt ream 60.00 Fryuy 240 mm “ 1.80 Fusnm 382 A KR T BH U R H. T H O M A S CO M PAN Y Cat. Code Cat. No. iat Aesaae Size Unit Price Word No. Description Size Unit Price Word 5218 ter a st atman No. 12, ea re 5268 Filter paper, Alpha............ 150 mm pack $0.25 Fynak poctheronatns eu a mr pac $. ‘usre 180 mm “ "33 Fynec 500mm “$80 Fuego 230 mm” 60 Fymnj 5220 | Filter paper, Wahtman No. 14 a a “ 2 Eyey folded................ 320 mm 3.20 Futiz 400 mm “ 137 Fane 385 mm “ 4.00 Futyp 4 iy 500mm“ «6.40 Funbj fees oe : f 500 mm “ 2.20 Fyogx 5222 Filter tones, Whatman No. 51.. BH an 7 eH ee 5269 do., but in sheets............. 20x20in. quire .55 Tete z ‘wuty ream 8.20 Fyoym 90 mm “ 1.40 Fuurg 5270 Filter paper ClippingS.. wee ec eas ee cece lb. -30 Fynof 110 mm “ 1.60 Fuvak 5271 “pulp, washed..............05. lib. 2.45 Fyqqa 125 mm “ 1.80 Fuvec 10)b. 22.00 Fyqus 150 mm “ 2.10 Fuviu 5276.“ “ Box, five tray............0065 ea. 4.00 Fyrkm ee mm “ re roe a Bees pees ound pattern, iron........... “114.00 Fyrzk mm “ . ‘uvun o., but wit! Siero 3 peau ee eae i - 5224 Filter paper, drop reaction, What- coe ara man No. 120.........-. 140x220 mm quire 1.30 Fuwml | 5284 FILTER PUMP, Chapman...... 334in. “1.45 Fytew 100 4.25 Fuwpe 434 in. ‘ 1.60 Fytli 5226 Filter paper, Whatman No. 29 black 55mm pack 34 Fuxis 53g in. “ 1.80 Fytro 70mm “ AQ Fuxmk 5286 “ “New form..... 334 in. “ 1.45 Fyuft 90 mm “ 50 Fucut 484in. “1.60 Fywin 110 mm “ 60 Fucyl 53%in. “ 1.80 Fyuth 125 mm 75 Fuyed 5288 “A “~~ Couplings. .... ein. “ 30 Fyuze 150mm“ «1.04 Fuyht Min. “ 30 Fyocy 185 mm “ 1.47 Fuykn ‘ din. “ 30 Fyvim 5228 Filter paper, Whatman No. 100... 50 strips “ 2.80 Fuyyk 5289 do., without thread........... Yin. “ 50 Fywab 100 strips “ 5.20 Fuzbe iin. “ 50 Fywoy 5230 Filter paper strips, Whatman No. 3gin. 50 Fywwi 130, for arsenic tests..... 120x2,5 mm 1000 «1.25 Fuzrz 5290 Filter pump, Geissler, glass..............++ i 1.00 Fyxsp 5250 Filter paper for agar............ 40x40em 25 1.25 Fyahj | 5292 “ Muencke, 1 suction tube. ..... “115 Fyyij : 100 4.50 Fyajf 5294 do., with manometer connecting tube..... " 2.25 Fyyuk 500 20.00 Fyamz: | 5296 Filter pump, Richards, brass... .. 7x¥ in. “ 1.65 Fyzle 5252 “ pibulous, sheets. 7... 15x18in. quire 40 Fybaw 7x36 in. “ 2.60 Fyzov ream 7.50 Fybfm : 13x34 in. “ 7.20 Fyzsn 5254 “ “ Chardinfolded...... 32embox 2.00 Fybzb | 5297 “ “Couplings, for No. 5296, size Oem “ 2.00 Fycer 18x34 IM... eee ee 75 Gaazb 5256 “ “ it ~ sheets: sacs. 50m 25 2.00 Fycve 5298 ie . with vacuum gauge, on base... “14.40 Gaaxy 5258 “ “ Prat-Dumas, white... 75mmpack .20 Fydor 5300 Water jet form.............. “24.25 Gabmu 100 mm “ 30 Fydth 5301 do., but for operation by steam.......... “24.25 Gacdl 125 mm “ (35 Fydzo 5302 Filter pump, blast and suction............. ue 19.60 Gacva 150 mm “ ‘40 Fyecp 5303 do., but with pressure gauge............- “27.60 Gadjy 200 mm “ ‘50 Fyefj 5304 Metal bands, only, for Nos. 5302/3......... “ 1.00 Gaeap 250 mm “ 65 Fyeid 5310 ‘Filter tubes, glass............... Gin. “ 25 Gacom: Y a“ 1.15 F, : Bin. “ 30 Gaerg ae a “ 1.95 tl 5311 do., but Pyrex glass........... 6xlin. “ 40 Gaffe 5259 — do., but folded.... ........... 75 mm “ 50 Fyfek 6x1} in. * 45 G flu 100mm“ —.70 Fifie ee 4 a ae : “ xilgin. “ 65 Gafzt i a “ a ae 5312 ‘Filter tube, Fresenius, with bulb....... c dances 30 Gagok 200 mm “ 1.10 Fyfsh 5314 «for crucibles......... 18 mm “ 15 Gahei 950 mm “ 1.30 Pyfat 20 mm 5 -20 Gahga 375mm “ 2.25 Fygdl ne a2 ae 500 mm “ 3.10 Fyghd 28 mm ‘ 32 Gahmo 5260 do., but sheets............-25+ 17x2lin. quire .45 Fygzs 32mm 37 Gahph ream 7.25 Fyhem a ie if on re 50 Gahwi 5262 Filter paper, Baker & Adamson 5324 FLASKS, Pyrex, flat bottom, vial & quality, double washed 90 mm pack 1.70 Fyhub Protithh ce 50 ml “ 17 Gatto fe cn Sie || || ESRI ae ta “ ° . Up 125 mm 3.40 Fyicl 150ml “ 20 Gaige 150 mm “ 4.20 Pyihb 200ml “22 Gaity 5264 Filter paper, J. G. No. 588 folded. 125 mm “ 85 Fyizw 1“ ; Ma i 300 m 25 Gaixg 150 mm 1.25 Fyjao i v4 ‘i jao 400 ml 27 Gajbi 185 mm 1.25 Fyjdi i 500ml “ 30 Gajfa 240 mm “ 1.75 Fyjha 700 ml “ 36 Gajjs 320mm“ 3.15 Fyjls 1000ml “ 43 Gajoh 385mm “ = 4.00 Fyjsd 1500ml “ 51 Gaj ss J yjwr 500 mm 5.00 Fykan 2000 ml “ 60 Gakaj 5265 Filter paper, S&S No. 589, black : 3000 ml “ -16 Gakjr ribbon...........-.5050+5 90 mm “ 1.70 Fykse 6000 ml “ 1.60 Gakin ; 110 mm “ 2.00 Fykwu Stopper No. 10... 12,000 ml “ 3.30 Gakog 5266 do., but white ribbon.......... 90 mm “ 1.70 Fylks Stopper No. 13... 12,000 ml “ 3.30 Gaksy 110 mm “ 2.00 Fylnl 24,000 ml “ 6.60 Gakzk 5268 Filter paper, Alpha...........--- 55mm “ 10 Fymed 5326 do., but Nonsol glass....:..... 30 ml “ -13 Gamez 4 70 mm “ Al Fymiv 60 ml “ 14 Gamir 90 mm “ 12 Fymlp 120ml “ -16 Gamoe 100 mm “ 14 Fymge 180ml “ 18 Gamtu 110 mm “ 16 Fymty 250 ml “ -19 Gamwo 130 mm “ 19 Fymaq 500ml “ 25 Gamzi 33 A R T H U R FL: T H Oo M A Ss es O M P N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 5326 Flasks, flat bottom, vial mouth, 5348 Flasks, Erlenmeyer, with glass ‘ Nonsol glass........... 1000mlea. $0.35 Ganda stopper..............- 250mlea. $0.75 Gehae 2000 ml ‘‘ 15 Ganhs : 500 ml “ 1.00 Gehdy oo a u ie ee 5350 do., but heavy Pyrex glass..... 250ml“ He ae ml “ i ann 500 ml “ 1.35 Gehst 12,000 ml “ 3.30 Ganrz . 1000 ml “ 1.80 Gehun 5328 Flasks, Eee eat bottom, heavy Syaald S86 5356 Flasks, transparent silica, flat bot- 9s ring’neeks, 4.0, cc wena yee m 38 Gaosu Taine acess eet aT ae 25 ml “ 4.25 Geiii 700 ml “ AT Gaovo ca i) a ue 5.75 Geilh 1000 ml “* 55 Gaozg 100ml “ = 7.50°Geioa 1500 ml _ 66 Gapdy 5357 do., but with stopper.......... © s25 inl 11.75 Gejeu 2000 ml -18 Gapio 50 ml “ 13.25 Gejjk ae uf . ie ee 100 ml “ 15.00 Gejme ml “ . ‘aps ‘ “ : Stopper No. 10... 12,000 ml “ 3.50 Gapun SHO) | Haste f! popper een stat a oy a “ a Cae 7 Stopper No. 13... 12,000 ml “ 3.50 Gapaf 2000 ml “ 4.50 Gekoy 5329 do., with rattan neck covering. .... on H , ie poe 5361 do., for Kjeldahl determinations 1000ml “ 4.80 Gelgo mm 4 a 5370 Flask, assay, glass, without pourout 150ml “ 18 Gelul 5330 Flasks, Nonsol, flat bottom, heavy 175ml “ 20 Gelyd ring PCs daria erentee 500 ml “ 28 Gasfr 250 ml “ ‘22 pate 3 1000 ml a 38 Gaskh 5371 do., with lip and pourout...... 125ml “ .13 Gemow 5332 do., round bottom, vial mouth. . 50 ml olT Gatnz “ - 250 ml 17 Gemrg 100 ml -18 Gattin 500ml “ ‘25 Gemuk a a “ a ae 5372 ‘Flask, assay beaker............. 250 ml “ .24 Genjg 300ml “ 28 Gaugh 500 ml “ 45 Genma 100ml “ 32 Gangh 1000 ml “ 60 Gengr 500ml “ 37 Gaumb 5378 “ Acetylization................00000. i 1.50 Geoep 700ml “5 Cau pu 5380 “Pyrex, copper determination 180ml “ 25 Geotk 1000 ml “ 56 Gauso e 250 ml “ 30 Geoxe 1500ml “ 71 Gauvi 5381 do., but Nonsol glass.......... 180 ml “ .20 Geppr Sanat 79 Gauge ; 250 ml “ .24 Gepuh 3000 ml “ 1.07 Gaveu 5386 Flask, Dewar vacuum, tube form, 5334 Flask, Pyrex, round bottom, long aes era a QU Hees Eh ca a0 ek ring neck. ............... 12,000 ml “ 3.75 Gaven ; se se edt 5336 do., but short heavy ring neck.. 22liter “ 7.00 Gawhj - 5387 do., but silvered.............. 100 mr * 3.50 Gerie BOliter “ 16.00 Gawlb 250mm 6.10 Gerly 5338 Flask, nitric acid balloon, Pyrex.. 72liter “ 38.00 Gawzy 5388 Supports, only, for Dewar flasks 5340 “Pyrex, round bottom, short Nos. 5386/7.............. 100mm" 1.25 Gesat ring neck.............. 200 ml “ .28 Gaydp 250mm 1.25 Gesdn 500ml “ 38 Gayif 5390 Flasks, Dewar vacuum, pear shaped, . 1000 m! “ 55 Gayma unsilvered, without base... 125ml “ 4.00 Gesrk 1500 ml “ 66 Gay} 250ml “ 5.00 Gesve Spe 78 Gigk 500ml“ 8.60 Geszu 3000 ml 99 Gayve 5391 do., but silvered.............. 125 ml “ 5.00 Getop 5000 ml “ 1.40 Gazbs 250 ml s 6.00 Getsh WOO BRIG Ue Nate ace a an ge Geen 500 ml 9.90 Getyv 7 eer upports, only, for Dewar flasks Se ES LEN: es 6 Bae Nos. 8390/1. :..2...060.44 125ml “ 1.00 Geumt 100ml “ 18 Geaiv a a 130ml “ “18 Gealp 500 ml 1.50 Geuue 200 ml “ .20 Geage 5396 FLASKS, DISTILLATION, Pyrex, 250 ml “‘ 22 Geaty with side tube at center of neck 25ml “ 36 Gevxv 300 ml “‘ 25 Gearg 50 ml “ 40 Gewap 500 ml “ 29 Gebak 100 ml ‘ 45 Gewdj 600 ml “ .31 Gebec 125 ml “ -50 Gewhb 750ml “ -34 Gebiu 200 ml ‘ -55 Gewlt 1000 ml “ A2 Gebnj 250 ml “ 60 Gewom 1500 ml “ 51 Gebuv 300ml “ 65 Gewrg 2000 ml “ 60 Gebyn 500 ml “ 10 Gewua 3000 ml “ 19 Geeef 700 ml “ 1.00 Gewys 4000 ml “ 1.00 Gecit 1000 ml “ 1.18 Gexbm 6000 ml ‘ 1.60 Gecin 1500 ml “‘ 1.45 Gexeg 5344 do., but Nonsol glass.......... 60 ml “ 14 Gedut 2000 ml “‘ 1.60 Gexriy 120ml “ 16 Gedyl 3000 ml “ 2.15 Geamq 180ml ‘ 18 Geebf 5398 Flasks, distillation, Engler, Pyrex. 100ml “ 60 Geynm 250 ml “ 19 Geefx 200 ml “ 65 Geyre 350 ml “ .24 Geeir ; 250 ml “ 10 Geywu 500 ml ‘ 25 Geemj 5400 Flasks, distillation, Nonsol glass, 700ml “ 32 Geega side tube at center of neck. 120ml “ 54 Geznl 1000 ml “ 38 Geeus 250ml “ -60 Geerd 2000 ml “ 75 Geexm 500 ml “ 80 Gezuz 5346 Flask, Erlenmeyer, Pyrex, with 1000 ml “ -95 Gezzn extra wide mouth......... 250 ml “‘ 22 Gefqz 5402 “ Ladenburg, Pyrex........ 500 ml “‘ 2.00 Ghark 500 ml “ 29 Gefzl 5403 “Hempel, Pyrex, with side 750 ml “ 34 Gegaf tube bent atend......... 500 ml ‘“ 1.50 Ghekh 1000 ml “ A2 Geggt 5406 “Creosote, Pyrex.......... 500 ml “ 1.75 Ghexg 2000 ml “ 60 Gegjn 5410 pr SC lAISCH Nacht oho 50 ml “ 15 Ghikd 5348 Flasks, Erlenmeyer, with glass 100ml “ 1.00 Ghiou stoppers sv sehiee nates ete 125 ml “ 50 Gegxk 250 ml “ 1.25 Ghism 384 35 A RR T H U R H : T H Oo M A § Cc O M P iA N Y Cat. : No. . Description Size «Unit = Price Word Noe none 5410 Flasks, Claisen .............. 500-mi , 0. . Description Size Unit Price Word Sail do. but jist euihaaes Moe oe aa 5461 vse volumetric, with glassstoppers 10mlea. $0.40 Gismn 250ml 1.80 Ghmue em eee 500ml “ 2.20 Ghniv a. | ee 1000 ml “ 3.00 Ghnyo 100 ml : 70 Gisyo 5412 Flask, dilation, Pyrex, with sido tt oe ube bent at right angle... 500 ml “ : se a sts” . Lcaypnanie herpes sil- ° ure ; a = ‘ 10 Gilek ica, round bottom......... 25ml “ 6.75 Ghudf es Oe ae ae (Soml 828 Ghag act 2000 ml LBD Gina) 5414 “distillation, Pyrex, for am- m 10.00 Ghujt 5462 ‘ do., Pyrex glass, without stopper aa sh e es Giuvs monia nitrogen distillations 2000 ml “ i , a eae 5420 “extraction, Pyrex, conical, sone ae pol Ge for mercury seal.......... 100ml “ 2.00 Ghykn” . bes a ee a oe : ye ¢ mi “ : 150ml “ 2.25 Ghyoe | 5463 —do., with solid Pyrex stopper... 100ml“ —1.60 Giaht a 250 ml 2.50 Ghyry 4 ‘ . fe 5422 extraction, Cottle .°...... 350ml “ 60 Giaft ea “ oes 4 ERG. Pyrex a00ml“ “$2 Ghee peace: avcemt 5426 filtering, without side tube 250 ml “ 20 Giblg : 4 i “ . ee : eel : a Giboz 5464 Flask, Volumetric, glass stopper ; ‘ Sait a ey and blue stripe. To contain 100ml “ 1.00 Giylj $428 do., but Pyrex glass........... 250ml “ 140 Gicoy maa prs Sim 500ml 54 Giesg 1oooml 210 Gigak 100ml “84 Giewi | 5465 Flask, Volumetric, with glass ae é 7 0 Giddu ~* stopper, to contain and deliver 100ml “ 80 Giznd : f 4000 ml 2.00 Gidgo : = 2 e , 5430 Flask, filtering, with side tube.... 250ml“ 50 Gidzf ae “Eee : 500ml “ 70 Gieaz room! “1.40 Gla a ut 1.00 Gieer 5466 Flask, Volumetric, without sone ; sia coh se 7 co Gay and without graduation... 100ml “ 30 Glamz 5431 do., but Pyrex glass........... 250 mit“ 10 Gievt i i , pe 500ml “ 95 Gieye 8 1000 ml “ r) Ge 1000 ml “ 1.45 Gifeu 5467 ‘do., but Pyrex glass........... 100 ml “ 44 Glejb / 2000ml “ —-2.40 Gifgm 250ml“ 60 Glen ; 400ml “ 4.00 Gifle 500ml “ ‘80 Glepo 5432 Flasks, filtering, with side tube and mo ae One stopcock...............-. 250ml “ 2.00 Gigaz 2000 ml es ic Gis : Pian ss a Gan 5468 ‘Flask, Volumetrio, wi with stopper but 5 y 5436 ie niteding ety aseibe sail i without graduation. ....... ~ 100ml a. 50 Glich funnel ground into neck.. 500ml “ 2.40 Gihbu zon “ pes dee Beets 1000 ml “ 3.00 Gikeo a eee a ring, Shaw. .......... 400ml “ 5.50 Gikdj ou «“ eee 540 7 woe ith ae * Fo5cal 85 Git a 5469 “ Giles, with stopper. sseeee oun . a a 3 1.80 Gloed 250ml“ 85 Giipg 2000 & 200ml “ in Caky sz Kjeldahl, Pyrex, found bot- 500 ml 1.10 Giisk 5470 “ Volumetric, with stopper and ie : on sath ore 300ml “ 98 Gijka bulb in neck. To contain. i a 7 1.00 Glozk 500ml “ 37 Gijor es ee 650ml “ 2 Gifu Net eh eee 800ml “ 45 Gikbr et eee 53 do. but Nonsol glass.......... 500ml“ 38 Gikrk iow 20 Gane Se a oes | Sum Gia 200ml 00 Glusm ks, Kjeldal yrex, roun ithout st “ fe oe Fs ha fia apets 28 Gilky 5471 _. do., without stopper......... oe a a : a Glyij 500ml “ 37 Gilop a 200ml“ 95 cui 800 ml “— 45 Gilry 250m “ 1.20 Ghee 5446 do. but flat bottom, long neck.. 300ml“ = .28 Gimhd_ som! © 180 Give "500ml “ 37 Gimlo 1000ml “2°30 Giyae 5448 Flask, moisture, Pyrex glass. ..... 1000ml “ —1.50 Ginbo ts, 2000ml ““ =. 3-70 es 5450 ‘ of copper........ 1000ml “ 9.60 Ginpl 5480 Flasks, Volumetri tified, with : . ae . 5452 soil, Pyrex glass.......... 200ml “ 2.25 Gioeh a ae he he w 300ml “ 2.50 Gioia .- out stopper. To contain... 50 ml -10 Gmapq some oe ome : an 100ml “1.40 Gmask 5454 sulphur, Johnson, Nonsol.. 275ml“ —«38 Gipao ee oe eee 5A56 “ 6 «Pyrex... 275ml “ 32 Giprf 500 ml : 2.50 Ginaer . 1000 ml 3.00 Gmeej 0 FLASKS, VOLUMETRIC, with- ts ant ore out stopper, to contain.... 10 ml “ 30 Giglr 5481. do., but tested by the Bureau of | he 25 ml “ ‘AO Gigok Standards. a contain..... 100ml “ 2.20 Gmewy som“ AB Giree | 250ml “ 2.60 Gmian . 100ml “ 48 Giquu 500 ml “ 3.30 Gmief 200ml “ 50 Giram 1000 ml “ 4.00 Gmiiz : solal 58 Gigs | 2000 ml“ 5.60 Gmilr 500 ml.“ 10 Girks 5482 Flasks, Volumetric, certified, with ! 1000ml “ 90, Girnl stopper. To contain....... 50 ml “ 1.60 Gmizo a 2000 ml “ 1.40 Girgf ei 100ml “ 1.75 Gmocd A R T H U R Ee T H oO M A S Cc Oo M PsA N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 5482 Flasks, Volumetric, certified, with 5554 Forceps, Specimen, nickel plated... .375mmea. $3.30 Gorjh stopper. To contain..... 200ml ea. $2.25 Gmoht 450 mm “ 4.00 Gormb 250ml “ 2.50 Gmokn 5555 a Cover glass, bent blades 105 mm “ 1.00 Gorza 500 ml “ 3.00 Gmope 5556 “ straight “ 115mm “ 65 Gosov 1000 ml “ 3.50 Gmotu 5557 “ “« « self- closing 125 mm “ 1.20 Gotdr 2000 ml “ 5.00 Gmowo 5558 e «© ~ Ehrlich.. 135mm “ 1.25 Gotya 5483 do., but tested by the Bureau of 5559 eo ea eee .. 115mm “ 1.00 Gouot Standards. To contain..... 100 ml “ 2.50 Gmuil 5560 do., but with locking device. . 115 mm “ 1.50 Goofl 250ml “ 3.50 Gmumd | 5561 Forceps, cover glass, Cornet. . 120 mm “ 50 Gowau 500 ml “ 3.80 Gmuqu 5562 “Stewart... af 20 Gownt 1000 ml “ 4.50 Gmuto 5563 “Slide, Kirkbride................. h -10 Goxel 2000 ml “‘ 6.00 Gmuwi 5564 * 6 BOSLOM so mice Gal she me ene a -10 Goyas 5484 Flasks, Volumetric, certified, with 5566 me OO MMOS tsi ecnae crane eee é 2.00 Goyop stopper. To deliver....... 100ml “ 1.75 Gmnyih q Sean 250 ml “ 2.50 Gmymz 5570 FUNNELS, Glass, 60° angle lin. 15 Gozva 500ml “ 3.05 Gmyro 18¢ in. : 15 Gozzs 1000 ml “ 3.50 Gmyvg Zin. * -20 Grade 2000 ml “ 5.00 Gmyya 2)gin. © 30 Gragy 5485 —do., but tested by the Bureau of 3in. * 35 Gralo Standards. To deliver..... 100 ml “ 2.55 Gnamu 314 in. i 35 Grapf 250ml “ 3.30 Gnapn din. * 40 Grauy 500 ml “ 3.85 Gnash Sin. © -60 Grazp 1000 ml “ 4.50 Gnavb Gin. -10 Greag 2000ml “ 6.40 Gnazt 7 in. 1,00 Greey 8in. “ 1.10 Greig 5500 FLASKS, SUGAR, Bates, 20°C... 100ml “ 80 Gneol Yin. “ 1.50 Grelk 200 ml “ 1.00 Gnesd 10in. “ 1.85 Greod 5501 do., but 27.5°C................ 100ml “80 Gnijs 12in. 3.00 Gresv 200 ml “ 1.00 Gnioh 5572 do, with long stems........ lin. “ 22 Grilg 5502 do., but without graduation..... 100ml “ 36 Gnoew 15g in. “ 24 Grioz 200ml “ 40 Gnohq 2in. “ 26 Griun 5504 =‘ Flask, sugar, Pyrex glass......... 100 ml “ 80 Gnoup 2144 in. “ -30 Griyf 5506 e SS SUlitnienwiak a ean 100 ml “ 1.00 Gnuhk 3in. “ 40 Grobu 5508 a “ Kohlrausch, 20°C... 100ml “ 60 Gnuuj 3in. “ 45 Groeo 200 ml “ 90 Gnuxd 4in. “ -50 Groig 200.6 ml ‘ 90 Gnybs 43in. “ 55 Gromy 500 ml “‘ 1.10 Gnyem 434 in, “ 60 Gropr 5509 do., but 27.5°C................ 100ml “ 60 Gnyth 6in. “ -10 Grotj 200 ml “ 90 Goams 5574 do., but with extra long thin stems 2in. “ 28 Grupl 200.6 ml “‘ 90 Goapl 214 in. “ 30 Gruub 500 ml “ 1.10 Goaud 3in. “ 35 Gruxv 5510 Flasks, sugar, two graduations... .50&55ml “ 40 Godli 3% in. “ 40 Gryam 100&110ml “ 60 Gobom 4in. “ 45 Gryfe 200 & 220 ml “ -10 Gobse 5577 Funnel, powder, short wide stem... 60 mm “ 20 Gryzn 5511 do., but 27.5°C... 22... 5500-5. 50&55ml “ 40 Gocha 80 mm “ 25 Guady 100 &110 ml “ -60 Goels 100 mm “ -30 Guahq 200 & 220 ml “ -10 Goerf 5578 “Sugar, stemless.......... 100 ml “ 25 Guarn 5512 ‘Flasks, sugar, Pyrex glass, with two 150 ml “ -30 Guboa graduations............ 100 & 110 ml “ 1.10 Godlr 225ml “ 35 Gubym 200 & 220 ml “‘ 1.25 Godok 5579 “ Victor-Meyer..:........ 200 mm “ 2.00 Gueme 5520 Alkalinityis: c.25 2 ssiasas 58.3 ml “ 60 Goefe 5580 “ Stemless, of copper...... 4in. “ 1.00 Gudna 5522 “Cassia, graduated........ 120 ml “ 1.80 Goesb 5581 5 “perforated. ..... 4in. “ 2.00 Guees 5524 “Fertilizer, short neck..... 250ml “ 90 Gofkr 5582 “Sugar, German silver..... 4in. “ 6.00 Guetn 5525 “Lactose, 20°C....... 102.6 ml “ 1.10 Gofem 5584 “Ribbed, glass........... 234 in. “ 22 Guftj 5526 4 Phosphoric Pt 200 ml “ 80 Goguv : 334 in. “ 28 Gufny 5528 i “Pyrex. 200 ml “ 90 Gohln 434 in. “ 32 Gufrq 5532 Flask, saponification. . ... 250ml “ 1.80 Goibg 534 in. “ A8 Gufuk 5534 “ ~ Viscosimeter, Saybolt. . ee 60 ml “ 1.25 Goirz 74 in. “ * 67 Gufyc 5536 7 s Certified... . 100 ml “ 1.95 Gojng 834 in. “ 1.25 Gugeu 200 ml “ 2.50 Gokey 1014 in. “ 1.85 Guggm 5537 do., but tested by the Bureau of 13in. “ 3.45 Gugma Standards. ixaccsaciscenains 100 ml “ 3.00 Gokyj 5585 “diagonal fluting, glass.... 70mm “ -30 Guhmz 200 ml “ 3.50 Goldz 100 mm “ 60 Guhro 5540 Flask heater, with 110 volt lamp........... 3 12.00 Golgy 160 mm “ 80 Guhui 5542 ne “sheet iron.......... 110mm “ 64 Gomew 200 mm “‘ 1.25 Guhae 130mm “ 1.04 Gomhg 240 mm “ 2.60 Guiaw 180mm “ 1.20 Gomli 5586 “glass, set of 3, small............. set -50 Guipr 220mm “ 1.36 Gomnd 5587 ‘““ Enamelware, with handle. 3in .ea. 15 Gujqo 270mm “ 1.60 Gomrv 4)4in. “ 1.00 Gujtt Gin. “ 1.30 Gujara 5548 FORCEPS, brass, Stralght 2h... ma hes ence i 35 Gonev 5588 “Hard rubber............ 4 pt. “ 55 Gukuf 5549 ENG ars ceveeeres ae x aver ot 35 Gonuo 1 pt. “ 80 Gulbr 5550 a “ivory tips.............. as 1.35 Gooki 1 pt. “ 1.00 Gulel 5551 “ steel, plain.......... 100 mm “ -14 Goozd 114 pt. “ 1.35 Gulid 112 mm “ 17 Gopfr 5590 “Buchner, Coors porcelain. 60 mm “ 1.08 Gulwa 125 mm “ 18 Goplf 75 mm “ 1.80 Gumas 150 mm “ -20 Gopoy 95 mm “ 2.34 Gumdm 5552 a glass tips. . .. 634¢in. “ 1.50 Goggo 115mm “ 2.52 Gumhe 5554 “ Specimen, nickel ‘plated 250 mm “ 2.00 Gordt 130 mm “ 4.32 Gumky 300 mm “ 2.50 Gorgn 155 mm “ 5.04 Gumop 36 a R_T H U R H. T H 5 No. is NM * Cc Oo 590 Funnel amma si c M P_A 592 Funnel, eral porcelain ‘a0 et Erice fon. | Nee Na 5594 beat eparable, Coors porcelai Cus $6.48 Gumrj . Descripti , porcelain. .... 50 ain. 4.80 Gunu eee Size U Code ee mm “ 72 ue 5644 Fun : nit Price Wate: a | ee nel Tubes, straight, conical 5596 a 2 ant cay Gaon ical top a mm ea. $0. a Gyhu x Fa ‘ 0" a 5598 porcelain, cone shaped... i ol Guorh | S646 do, but with thistle To pees 5600 “Hot water, double wall 45 mm “ or cae ree a mm “ 2 ae . c ; wall, . qdi 50 mm “ ole Gye 5601 do., but ee al, detachable legs. . a 5647 300 mm “ 12 Gyjan BE St Ne ‘i 7.20 Gurej 5648 do., with loop, conical 400 mm “ 16 Gyjic 5603 anel, hot water, single wall, copper... 6.00 Gurmi do, “ ical top...... 300 mm “ 18 Gyjmp doubl opper... .. ig pt thistle to mm 25 5604 mour pattern e wall tin, Planta- 4.00 Gusga aed, 200mm“ 18 Gykga ANS do., but of copper. Se 125 mm “ 4 5649 —do., wi 300 mm “* .20 care Funnel heater, of | ned 125 mm “ AO Gusiz 0., with loop, one bulb 400 mm “‘ Gylby 5606 do, but block ee coil... ........ ee. 6.40 Guink 55h ‘eal'to mp ulb and con- 25 Gyled 5607 do., but copper Ce samen skagemenane e 5.00 Guude | 5651 do., but with thistle top... 300 mm “ 30 Gutea'* 5610 memeicearytaneiaseen ee Goin do., with double loop bre bulbs aon: 30 oe FUNNEL, SEPARATO 80 Gurml 5652 and thistle top. ate mee =atl Gyles abc stopper RY, heavy glass do., but with short-stem....... 0mm “ 40 Gym tiereeneeses 250 ml “ 5656 FUN earn © ania icon ao 230 oe 5658 ve SUPPORT, Ostwald,for one funnel “ Ree “ 561 pou “4.00 Guaclm triangular, wood 3in. “ * Gynas * 2 do., funnel shape 4000 ml “ res Guwof 4in. “ 40 Gyolm seeeeseeeesees 200ml ee Gur | 5660 Funnel ome 40 Gop faa “ ae oo oe ane support, wood, for one funnel aaa 40 Ones ml “ 7 ‘a 62 di a ag ote Wer rie eo Be 1.10 we a a ee ee do., two funnels, one on each side «80 ae a ee eee: ae » Pro Tomes, Dome on one Se, es ai at elie. oe fa Rie Ere a 115 yay, Bm RG | se do, what a... A egies an Glane 5618 ' ml“ 1.20 oe ee ie aaa 4.00 Gyspz do., cylindrical, open to 100ml “ 1 pa 5668 do. wi slotted holes.......... 2 unnels “ 2.00 Gyth 3 ; Di terses 30 ml “ 1 30 Guats 5669 a ua metal clamp......... funnels “ 2.50 Gytyg mal « ! a Gaoahm o., Leach, for separator aia 4 funnels “ 65 rd font 110 Gaol | See URNA Beeseeeee "250 Gyn 150ml ee 1 50 Gaus 5677 Fire clay casi ipl Crucible, No. 15 “ 5619 ¥ 200ml “ 1.70 Guoany 5678 Lid, only, f tN, for No. 5676........+.--. ;, 40.00 Gyors do., cylindrical, sto 250ml “ avy 5679 Grate, onl oe Nb S676c.c nik ner 6.00 G , Stoppered...... 30ml “ 1.90 Gwazd 5682 Fu 6, only, for No. 5676..............00- “ 3.50 ywor FOml “ 1.10 Gwen» rnace, Fletcher Muffle.......... No.3 “975 Gyarg gms ier | Nos | en ee ee: Tae Nod“ 7800 Grease 5620 ai 200ml “ ae Poe 5683 Domes, ativatel 1 Tee : 102.00 Gyedr o., heavy glass, short stem a «210 Guia plumbago, for. No.3 “ ee a 5621 do, es «2.60 Gavirj No.4 “ 85 Gyazy meres Se, | tte i ie i. 00 Gw , plumba, 0.6 “ : ane do., double graduated, long stem intent 450 ie go, for furnace... No.3 “ ane Boaty 624 Fu “2.25 Gouda No.4“ 3150 Haben mci pear shaped, au 3.40 Gwuks | 5686 Furn a ae 125 Hab se aaa 830ml“ s 5687 poe TIRE, crucible No. 68 te fable 60 ml “ a es 5688 Furnace, Monito No: G3 ns oe teat : 45.00 Hacbo 225ml Vee ce oe clay slab, Uo Mer. eee ml “ 1.75 Gw ire clay sab, for No. 8588... e000. “ 0 Hacer’ 500ml “ yho | 5691 Plat y, for No. 5688.0... “1.20 He ws ial 38 Go| 3 ewes aie o., with ai : “ 2 ; ible blast, No. 40a... with air vent in stopper... 125 ma eau sof rie get Ee at ita. on, ie a Hafre 950ml “ et Gyaje 5695 Furnace Meteher en for No. 5692 awe ¥ 2.00 Haglq 500ml“ 2.75 Gyano | 9696 » Fletcher crucible blast No. 40b... 1.00 Hahch 56 1000 ml “ 438 Gyarn 5697 “~~ Bod No. 41 2 8.75 Hahsa 26 Funnel, separato ee it Gee ay. Cee ne ae Me 5696.0... 10.50 Hai 5627 P “ ry, creosote...... 125 ml “ 6.10 Gybav 5699 Dome, o ria only, for No. 5696... Ste ey ia 5.50 Hani cod “ a for ether..... 160ml er Gycka 5700 Furnace, Fk for No. 5696...... Seay ES . 2.00 Haas 600 nickel determinations... Lis ay oe eee on ieee | ee Hakra Squibb teens 125ml “ re Gydzu 5701 Fire cla Pe 141 nil Ne dl a SAL eru- it a ds 5632 soni 2a Gyene | | BU Ely se Ee er lee aces “25.00 Halng “ 4 500 ml “ 2 Gyegl 5703 Plumbago m ffl 0; B700s ss sv chacestatses 4 17.00 Hambe LaWall...... o5'm! 10 Gyeif 5704 Furnace Wie efor No. 5700.......... Peed 410 Ham 5 50 ml “ ia Gyfib , Wiesnegg muffle........ ‘Ahan : 4.10 Manin m0 2 gt — oat fee 5705 Muffles, cl pean, at Be t 5642 3 aos ipticadd con OO 2.00 Gyfte , clay, for No. 5704. urner “ 50.00 H make dis ropping, Walter...... eo aa ie 1.50 Gyglu Ce ae ee pumer “ 1.35 he FUNNEL TUBES, strai 2.00 Gyhbn | 5707 Fire-clay eae Combustion. Le 1.60 Hao : sigh oi ca eeanroageneta gi Ses fea 200 mm “ 14 Gyrhg : aon; Bas heated. 25cm “ 1.00 Hagha 35cm “ 37.00 Harfr 450m “ aa 50 Harkh 1.00 Harna 37. A R aT H U R Hi. ‘T H O M A Ss Cc O M P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 5708 Furnace, combustion, gas heated... 60cm ea. $59.75 Harrs 5735 Rheostat, only, 220 volts. For.. FD-206ea. $35.00 Herat 5709 Clay tiles, for No. 5708.......... lin. “ a Hashm 5736 Refractory, only, for furnace..... FD-201 “ 10.00 Herog : 234 in. “ .20 Hasle FD-202 “ 15.00 Hers: 5710 Clay gutter, for No. 5708........ 10in. “ 16 Hatld FD-203 “ 20.00 Herwa 5711 Furnace, combustion, with burners FD-204 “ 30.00 Hesas for any kind of gas........ 25cm “ 37.00 Haucy FD-206 “ 55.00 Hesek 35cm “ ae Hauds 5737 ~Chromel “‘A’’wire, 110 volts...... FD-201 “ 6.00 Hesyv 45cm “ 00 Haufo FD-202 “ 9.50 Heten 60cm “ 59.75 Haujg FD-203 “ 16.00 Hethd 5712 Furnace, combustion, modified form, FD-204 “ 23.00 Hetmt gas heated............... 38em “ 54.00 Haurd FD-206 “ = 35.00 Hette 56cm “ 64.00 Havdr 5738 fe Ee Ee BOD Sivas FD-201 “ 6.00 Heulu 80cm “ = 78.00 Havlb FD-202 “ 9.50 Heuon 5713 Top tiles for No. 5712.................... a 20 Hawes FD-203 “ = 16.00 Heusf 5714 Furnace, combustion, modified form, FD-204 “ 23.00 Heuwx with burners for any kind of gas FD-206 “ 35.00 Hevap 38cm “ zy He 5739 Heating unit, for 110 volts...... - FD-201 “ = 16.00 Hevvy - 56em “ A awui FD-202 “ = 24.50 Hevzq 80cm “ 78.00 Hawyz FD-203 “ 36.00 Hewck 5715 Furnace, tube, I'reas electric,..... 110 volt “ 235.00 Hazve FD-204 “ 53.00 Heufe 5716 Sone “ 220 volt “ 235.00 Hayka FD-206 “ 105.00 Hewku 5717 “ ©" Garis’. cscs cuews 5tubes “ 22.50 Hazbr 5740 ne LEE OOo ates cn iaas FD-201 “ 16.00 Hezan 5718 Glass tubes for furnaces......... 415 mm “ 40 Hazeu FD-202 “ 24.50 Heziz 500 mm “ A5 Heade FD-203 “ 36.00 Hexnm 615 mm “ 50 Heagy FD-204 “ 53.00 Hexre 5719 — Glass tube for Carius or Freas Fur- FD-206 “ = 105.00 Hexwu nace, one end sealed....... 24xlin. “ 10 Hebaj 5720 do., but of Pyrex glass......... 24x1in. “ 1.60 Hebsy 5746 FURNACE, COMBUSTION TUBE, HOSKINS, without rheostat. 5722 FURNACE, CRUCIBLE, HOSKINS, For 110 volts............. FDH-302 “ 30.00 Heylg without theostat. For 110 volts : 5747 _do., but for 220 volts.......... FDH-302 “ 30.00 Heyzn ee i“ au ae 5748 Rheostat, only, for above, 110 volts........ “12.00 Hezty es fee 5749 SS DO MS sso “12.00 Hiaki FD-104 A 85.00 Hedez 5750 Refractory, only, forfurnace...... FDH-302 “ 6.00 Hibab Dies ee on ‘type HD-99 or e; 110 volts... pe66 “ ae "u rheostat and transf -99 “ 35.00 - vee = 60 - 125 Hee nh idaaee Ie i cycle, a. c.. ca ; a for ‘ Hufuj 5786 Type 64 “ 2.00 Hogaj | 5822 Transformer, only; ahove; 110 vols... 79.00 Hugsm do., top or botto Type 66 “ 3.50 Hogit 5823 Protecting sleeve, f 0 volt, 60 cycle, a. es 14.00 Huhig m; for 110 and 220 volts 4.75 Hogml Return bend heating ae furnace........ “ 00 rae Type50 “ 5828 F Ronee 00 Huios Type ne ote Holes asa “HIGH-TEMP.” 5.00 Hujie 5787 do., si Type 54 “ Ei ies 5829 do fo olka, O.. «., ELECTRIC, 0., side; for 110 and 220 volts. ae 56 “ 6.75 ed 5830 se i en lb @ ca Type 88“ 210.00 Hukel , Type 50 “128 Hoi 5831 Receatndle.A. al, granular.......... aS 225.00 Hulas ° 5788 Type 54 “ 2.00 Hoiir | 5833 Pedestal B...--.-.- aire ie soiens = 1.50 Hulop do., top or b Type 56 “ 3.50 Hoimj 5834 Cylinder Boscsccscsssessiiereisseesee ra 3.00 Humlo ottom; 220 volts... Type 60: “ 4.75 Hoiga 3835 Cover ring psecon tats es iis : 250 Hunem Type 62 “ 1.75 Hojey | 5836 Gover Hg Does serene “4.50 Hund 5 ype 64 “ 2.75 Hojo | 5837 Top smn Boose cere “1.50 Huono 789 do., side; f T a 450 Homi | 58 Bottom segment Goss. 0 ns “ 4.00. Hupfe , side; 10r 290 volts......--- oe i 6.75 Hojrz =a Cover plug K. austen a daneaid Saatuaay a) oe : : one ii 4.00 Hugef Type 62 “ 1.25 Hokoc | 5841 Gove lig ese “ 3.50 Hurju i tat Types. 2 oe | aaa Topeltade Gg gan one eating unit, top or bottom; 110 wee 66“ ATS Hk 5883 Baek leotrode tas ee “6.50 Hutec Type 60 “ 5845 Grube H.oeseosticsicern cf 2.50 Huuaj Type 62 “ 4.50 Holgz 5846 Bot beds ‘i 1.25 Huuog +t 6 “ 7.00 Holir 5847 Bottom busbar pe nanccaeas ees “ 4.00 Huvhu 5791 din da aoe 4 10.50 Holxj Nickel contact pl Da eae aaa pee ate 3.00 Husah ., Side; 110 volts.......-- hoe o 15.75 onal 5 Persie eatin ~ , . 7 ‘ng as “ 3.50 Homru ee asia Gea EOI 4.50 Huskm Type e “5.28 Homai Multiple Borie (COMBUSTION Type 66 ae Honac | 5851 d stats; for 110 ee with threerheo- 15 Honeu 5852 Retre ‘but foe'220 yolks... 42: Type 423 “ =: 175.00 A RobsnysIONEy. aseneryeoinses Type 123 “ 175,00 ae eeu pauaads 4in. “ ‘ayo 2.00 Huzod 39 A R aT H U R H. T 4H M ASS Cc O M P fea 12.00 Ihk 6188 do., for both light and heavy liquids; with- volt d.c. or a.c........... 12xl2in, A 2u out thermioiieteree ss 70-10 & 0-70 “ 3.85 Ijpuv 6161 do., for 220. volt d.c. ora.c.... 12x12in. 12.00 Ihlop 6190 Hydrometer, Baume, for liquids lighter than 6152 Heating unit, only, for No. 6160.. 110 volt “ 4.00 Ihmio WA LEM cid canoe nineties a le 20-10 “ 1.60 Ljrof 6163 do., but 220 volt...................000. ~ 4.00 Ihnbo 30-20 “ 1.60 Ljsah 6164 Hot plate, Hoskins electric, three 40-30 “ 1.60 Ljsoe heat; for 110 volt d.c. ora. c. 12x12in. “ 40.00 Ihnub 50-40 “ 1.60 Ijsus 6165 do., for 220 volt d.c. or a.c.... 12x12in. “ 40.00 Tholt 60-50 “ 1.60 Ijiag 6166 Hot plate, Hoskins electric, three 70-60 “ 1.60 Ijtod heat; for 110 volt d. c. or a.¢.12x18 in. “ 57.50 Ihozg 80-70 “ 1.60 Ijuaf 18x24in. “ 87.50 Ihpdl 90-80“ 1.60 Ijuex 18x36in. “ 110.00 Zhpha 70-10 “ 1.60 Ijujn 6167 do., for 220 volt d.c. or a.c.... 12x18in. “ 57.90 Ihgix 6191 do., for small quantities........ 20-10 “ 1.60 Ijuwm 18x24in. “ 87.50 Ihgnm 30-20 “ 1.60 Ijuzg 18x36in. “ 110.00 Ihgre . 40-30 “ 1.60 Zjvio 6168 Heating unit, only, 110 volts..... 12x12in. “ 12.00 Ihriw 50-40 “ 1.60 Ijvob 12x18in. “ = 14.50 Thrlg 60-50 “ 1.60 Ijoyh 42 A Ss CO A R T H U R H. T H oO M M P A N a Cod = lo Description Size Unit Price Word nat S d | No. GI81 | Hydometer, Baume forsmall quantities 70-80 ca, $1.60 Twin | 6204 Hydrometer Sp. Gr, Prob size Unit Price Word 0-70 1.60 Tjwuo y! rome ee = ee reading to “ é Ween or 4 rf 6192 Hydrometers Baume, for liquids faves Pehle ee “eiTaD- 780 ea. $2.70 Thnul Pie ea ae 1010 1.80 Ziyi ; eee: peg ee « ys0 7 . 840-1. 2.70 20-30 * 130 oe 6205 do., set of 8 in case, with thermometer Thifp 30-40 “ 150 ne =F 20 Tse a shaeare ssncnees event 8 set 26.50 Ikys tae re pada 6206 _do., with Bu. of Standards certificate..... “ 44.75 Thake 50-60 150 ie 6207 Hydrometer, alcohol, Tralle and Proof scales. ea 1.60 Tlafl 80-70“ 150 oe 6208 do., but with enclosed thermometer “450 fe. 6193 do, for small quantities........ O10" 130 tea | drometer,aleool, U.S. Interal Revenue : 10-20 “ 150 Thame Bureau pattern wa pe anales ss 0-100 “ 2.50 Ilbnt 20-30 “ 150 Ikaro 80-120 “ 2.50 Ilbth 3040“ 150 Thaw 100-140 * 2.50 Ileat 0 20 ; 150 kaze Pe : 2.50 Ilemy isd, Sayaioiatets’ Haiune, fonhiquldisbaavier chan 1.50 Ikbaw 6210 Hydrometer, alcohol, set of 3, covering range eae water: printed soale....... 030 “ 50 Them sie: vd from 30 to 100% volume........... set 8.60 Ildhe 0-50 : 50 Therm ner y ometer, eres anieles Baume oe ea. 1.30 Ilear 6197 Hydrometers, Twaddle, for liquids ha sists 6215 cea a on ‘ in Tae tliat WAGE. cos cescee ce 0-10 y 1.20 Iheel 0., but with enclosed thermometer ae i ae IUfjy 24 1.00 Thekf | 6216 Hydrometer, lime, a ae de 248 LO helo | 217 tae J a 2B 102 « 100 Tie — thermometer and on : « | sist "100 Fine | 21g Hr isa 0105 «130 Te do., for small quantities........ 0-10 “ 1.00 Ikglo 6220 e ee ai ia oe ae sue : 1.00 Tkguy printed scale. eh a 1 joi is Bs : 1.00 Ikhbo 6222 Hydrometer, sugar “and ‘syrup, Brix i med (fea 100 Tekin —5° to -+5° in 1/l0ths .. eg : 2-10 1.00 Ikhms | 6223 do, Baumescale.............. 0-20 = eae as GTR, eee: (Eagan tere 0-20 125 Ile : -160 “ 1.00 Ikibn a Ili 6200 Hydr ; ydrometer, Brix, grad. to 14°... an i‘ ‘ o ial on HYGROMETER, Mason.. - 10-120°F. i 5.00 Rens - CU, 31 Silk wicks, for No. 6230 d i “1,60 Thiru |) 6231 Sill wicks, for No. 6230. ...-..--.-- 2... bo 6201 ~ do., o to 1/10°, and calibrated at ine oy 6233 Hygrometer Hero 8 ei: kee i it OF SUBAE. eee eee 175 tite, | Geet Wika only ENO OBI oe Howe ; ly for No. 6232..............+-- : i up: LRTI | Bi Heewot,ae ros 0" 18 te 30-40 “ 178 Them 6237 Wicks, se r, only, for No. 6235.......... 4.00 Ilshp : ly, for No. 6235.............. ae. Ae ee) ee Hygrometer, (Hygrodeik)........ 0-100". en, 1750 Tad a m0 145 Tso 6239 Thermometers, only, for No. 6238. Left“ 3.25 Tae 2 do., but precision............. oo . a ae 6240 Wicks, only, for No. 6238 Right ie aH a ; 624 only, for No. 6238...........+..5 doz 1. ay oe Hivas 246 Induction Coils, Ruhmkorff phase Mio. ea. 5.50 Ilwye 30-40 “ 35 win. 8.25 Ilzeq . one as a ae lin.“ — 16.00 Tia LAO) & cit ° B me 20-60 “3.0 Thotn 6250 JARS, MUSEUM, Rectangular, with fat 6203 do., precision, with thermometer 0-10 “ 7.00 Thou ground = lids aap aaa ae ee peehis 10-20 7.00 Ikprz Recs aegeee 20-30“ 7.00 Ikgah ee dee tee 30-40“ 7.00 Ikqoe ee bey ie 40-50“ 7.00 Ikqyk ee awe soo 700 ry Noe “120 Tee ‘gé : bs . « ye 6204 Hydrometer, Sp. Gr. Precision, reading to oe rae fi i et between 3rd and 4th decimal place ie “ ae 0.700-0.76 2.70 Ikiae eee: Fee tee 0.760-0.8 2-70 Iktli ae A a ce 0.820-0.880 “ 2.70 Iktup Nol“ oe cea 0.880-0.940 “ 2.70 Ikucz © No. 12 “ Sie 0,940-1.000 “ 2.70 Tkuft Nee: Eee ana? 1,000-1.060 “ 2.70 Ikwin No. 13a" ee 1.060-1.120 © 2.70 Ikwmg Noid “ Penge 1120-1180 “ 2.70 Ikura D> ae 1190-1240 “ 2.70 Thus NT gee Tet 1.240-1.300 “ 2.70 Ikvac No. 15 “ He iene 1300-1360 “ 2.70 Ikvim No. 16 “ ropa 1360-1420 “ 2.70 Tkoun Oe. se Taso S6 I No. 17 3.24 Imbud J J 10 Ikwet No. 18 “ 14. 1'480-1.540 “ 2.70 Ik oe woy No.19“ = 18 1540-1600 “ 2.70 Ikuye No.20 “ cel 0. 20 24.00 Imew; “ y 1.600-1.660 : 2.70 Ikaes No. 21 “ 32.80 Imdbo 1.660-1.72 2.70 Ikale No.22 25.20 Imdlu 43 A R T H U R hes T H Oo M A Ss Cc O M P N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 6252 Jars, American Medical Museum, rectangular; 6263 Lids, only, for No. 6262 jars...... 244in.ea. $0.07 Indan patent construction....... No. lea. $0.55 Imeiz 3 in. “ 15 Indir No. 2 “ 10 Imeno 5in. “ 26 Indse No. 3 “ 1.35 Imeqi 614 in. “ 37 Indwu No. 4 “ 2.50 Imevy 754 in. “ 65 Indzo No. 5 “ 2.10 Imezq 1144in. “ 1.70 Ineci No. 6 “ 2.50 Imfeg 6264 Clamps, only, for No. 6262 jars... 234 in. “ 33 Ineqf No. 7 “ 2.10 Imfiy 34 in. “ 40 Inelz No. 8 “ 3.40 Imfol 5in. “ 62 Inexr No. 9 “ 3.50 Imgan 614 in. “ 13 Infal No. 10 “ 8.00 Imglr 75a in. “ 1.16 Infkr No.11 “ — 13.00 Inmgse 114i. “ 2.25 Infre 6253 Specimen support for No. 6252 jars No. 1 “ 10 Imhux 6265 Rubbers, only, for No. 6262 jars.. 234 in. “ 03 Ingiu No. 2 “ 10 Imial 34in. “ -ll Ingrd No. 3 “ 10 Imidf Sin, “ 25 Ingyn No. 4 “ 12 Imihx 614 in. “ -30 Inhef No. 5 “ 10 Imikr 754 in. “ 48 Inhjr No. 6 “ 10 Imige 114 in. “ 1.10 Inhpe No. 7“ 12 Imity 6266 Jars, standard specimen, wide mouth, and No. 8 12 Imiws ground in stoppers........ 2x1%in. “ 33 Iniko No. 9 “ 12 Imizm 3xl4in. “ 34 Ininh No. 10 “ 15 Imjec 2146x2in. “ 36 Initv No.11 “ 15 Imjiu 334x2in. “ 39 Iniwp 6254 Specimen frame support for No. 6252 jars 5x2in. “ AS Inizj No. 1“ 25 Imkog 314x214 in. “ AG Injir No. 2 “ 25 Imkxo 5x214 in. “ -51 Injus No. 3 “ 25 Imlea 7x2 in. “ 51 Injzi No. 4 “ 30 Imlof 4x3in. “ 60 Inkda No. 5 “ 30 Immah 6x3 in. “ 68 Inkhs No. 6 “ 35 Immir 8x3in. “ 80 Inkkm No. 7 “ 35 Immqa 6x334 in. “ 90 Inknf No. 8 “ 35 Immus 8x334 in. “ 1.08 Inkal No. 9 “ 40 Immyk 10x334 in. “ 1.28 Inlaf No. 10 “ 40 Imney 5x414 in. “ 1.11 Inlip No. 11 “ 40 Imnur 8x4iZ in. “ 1.37 Inluq 6256 Jars, Museum, Hopkins-Columbia. 12x6cm “ .12 Imomh 12x41 in. “ 1.65 Inmew 15x8cm “ 1.14 Imopa 7x6in. “ 1.95 Inmst 18xl4cem “ 2.70 Imots 10x6in. ‘ 2.56 Innad ccm ae és ae 6268 Jars, museum, with foot and ground in stop- : meg) ith knob 734x454 in. “ 2.40 Innzi o4x14.50m “ 3.25 Impdy per with knob........... gx45, in. 40 Innzi 30x15em “ 4.00 Impli 6269 do., but with ground on stopper with knob ; De 734x434 in. “ 1.80 Inond 35x9.5em “ 3.00 Tm ae 10 Invi PUP | 6270 Jars, dressin 4xdin. “1.40 Inpil 35x30cm “ 20.70 Imagen ; Bia te caacerce na a He 6258 Jars, storage, constricted neck.. eae in. “ 2.35 Imryf 6272 “ Tnverted specimen....... ..334x134in. “ 97 Inrer 4x834 in. 4.75 Imsil 43/x2in, 31 I 1114x1014 in. “ 5.00 Imsto ee bar Bo gee 1234x1034 in.“ 6.50 Imlby a, eae Co rantrd 4 734x234 in. 51 Insfo 1314x11)4 in. 8.15 Imtik 9x354 in. “ 6259 Rubber gaskets for No. 6258..... 6in. “ 10 Imuhl on Bae 68 Insle 884 in. “© 110 Tmubf heats, Sle eee 1034 in.“ 10 Imuny | g974 « Pregervi ; ee eae 1034 in. “ 10 Imugs reserving, green glass...... 4% pt. a 12 Inubu 1igin. “© 10 Imutm Bee ean 6260 Jars, storage, with countersunk knob in tid 6278 “ 1 to aoe “ pena 314x61; in. “ 80 Imouj clamp top...... 8 oz. a 18 Invav 43;x614 in. “ 1.00 Imwep 18 oz . 20 Invlz 5x814 in. “ 1.80 Imwou : : 28 07 23 Inorm 6x934 in. “ 1.90 Imwya | 6279 Metallic clamps for No. 6278 jars.......... doz. 40 Inzid 634x1034 in. “ 3.75 Imaxeo 6280 Rubber gaskets for No. 6278 jars.......... hi 25 Inyic 734x114 in. “ 4.40 Imala G283: Jara fam scien let wae 114x114 in. ea. 14 Inysb 6262 Jars, standard museum, withclamp 4x24 in. “ 95 Imyjd 234x214 in. “ -20 Inzar 8x21/ in. “ 1.05 Imynu 3x254 in, “ 22. Inzib 6x31 in. “ 1.40 Imygo—. 4x3in. “ 25 Inzuc 8x34 in. “ 1.50 Imyti — 6x3 in. “ 30 Inzzs 12x34 in. “ 1.75 Imyzxa ~ 484x4in. “ 50 Ioadi 18x3% in. “ 2.10 Imzem 6284 Jars, screw cap, cork lined....... loz.doz. 1.00 Ioaxt 8x5in. “ 2.65 Imzie 202. “ 1.10 Ioban 12x5in. “ 3.15 Imznt ~ 4 oz. “ 1.35 Iobhz 18x5in. “ 3.65 Imzuf 8 oz. “ 1.80 Iobmp 8x614 in. “ 3.40 Inaaqg-*|__ 16 oz. “ 2.70 Lobpi 12x64 in. “ 3.80 Inadk ~) 6285 do., but square............... loz. “ 1.00 Iochy 8x75¢in. “ 5.25 Inahe ~~ 202. “ 1.10 Ioclg 12x75 in. “ 6.00 Inams ~J 4oz. “ 1.35 Iocoj 18x75¢ in. “ 7.00 Inaple. | 6286 Jars, ointment, screw cap........ loz. “ 1.45 Iodiv 24x75¢ in. “ 8.00 Inaubd |. 202. “ 2.15 Iodlp 36x75¢ in. “ 10.50 Inaxv 402. “ 2.60 Iodq 12x11in. “ 12.40 Inbap 6288 “ Glycerine, screw cap........ 4% oz. “ 1.20 Ioefa 18x11}4 in. “ 15.75 Inblt loz. “ 1.40 Ioelo 24x1114 in. “ 19.70 Inbua = 20z. “ 1.70 Ioerb \ a4 A R T H U R H. T H O M A_ S Cc Oo M P A N Y Cat. Code Cat. Nas pesrinviod Size Unit Price Word | No. Description Size Unit Price Word 6290 Jars, Precipitating, straight. ..... 125 mlea. $0.30 Iofpe 6320 Lamp, Alcohol, glass............... 30ml ea. $0.30 Ipiob Fe wt . e ie 60 ml “ 40 Ipirv 44 ON Logea, 100ml “ AS Ipi 1000 ml 2 1.00 Togis 6321 Wicking, for alcohol lamps.............. : bd. 15 tee a sf Ln sy Vans rae, Japanese, sheets......7!4xllin. pkg. .40 Ipilf 50 Tokai ia aboot oO ieee vel, round..................5 15 mm ea. 15 [pnij 10,000 ml “ 5.00 ohi é 6291 do., but conieal............... 8 oz. “ 85 Take 6328 Maeners, Bar eh ees 150 mm “ 30 Ipohk 16 oz. “ 90 Tohzt 200 mm “ A0 Ipole - os eae 6329 “ Horseshoe, armature 100 mm ‘ 25 Ipoxd gal. “ 00 Loikm 150 mm “ 90 Inpe 1 gal. “ 2.50 Ioinf 6332. MAGNIFIERS, Pocket, single lens No. 56 “ 1.35 Tha 2 gal. “ 5.00 Joisy No. 62 “ 1.75 Ipgig Sgal. “ 10.00 Joizh No. 68 “ 2.25 Ipgquh 6292 Jars, waste, stoneware.......... 2 gal. “ 1.20 Iojsu 6333 do., but double Jens........... No. 57 “ 2.50 Ipska 4 gal. ‘ 2.20 Iojyt No. 63 “ 3.35 Ipsor a «330 Lok | 6334 do,, but triple | No 103 300 Ipcak 7 okio o., but triple lens............ 0 é 8 gal. “ 4.85 Ioknd 6335 Magnifiers, doublet, for use on dissecting mi- oe ; 12 gal. ‘ 6.25 Iokst Croscopes........... 00005 -No 1“ 1.75 Ipush 6293 do., but without cover......... 2 gal. “ 1.00 Toljl No 2“ 1.75 Ipuvb 4gal. “ 1.95 Iolne e No. 3 “ 1.75 Ipuct 5 gal. “ 2.55 Tolru 6336 do., but mounted in handle..... No. 6 “ 1.75 Tp 6 gal. “ 2.90 Iolxi 6337 do., but pocket mounting...... No. 7 “ 2.00 Ipyck 8 gal. “ 445 Iomac " : No. 7: 2.00 Toaf ; < m o. 7a “ e . 12 gal. “ 5.75 Iomeu 6338 Magnifiers, Coddington, in folding case. a 6294 Covers for No. 6293 jars......... 2 gal. “ 20 Iomyf No. 163 “ 3.25 Ipyzp Agal. “ 25 Toner No. 162 “ 3.25 [paix at a ve a Dee No. 161“ - 3.25 Ipeuy gal. “ -30 Ion No. 160 “ 3.25 Igqaak 8 gal. “ 40 Tonqu 6339 do., but for dissecting microscopes. ; } 12 gal. “ -50 Tonto : No. 163a “ 3.00 Igayn 6298 Knife, laboratory............. Blade 334 in. “ 20 Ioome No. 162a “ 3.00 Igbeb No. 16la “ 3.00 Igbra L ; No. 160a “ 3.00 Igchu 6300 ABELS, Dennison, gummed, with red border 6340 Magnifier, Triple Aplanat....... No. 168 “ 6.50 Igeag No. 225 box 10 Lopid No. 167 “ 6.50 Igegu ve a “ 7 ee No. 166 “ 6.50 Igekm 0. i 10 Iopso No. 165 “ 6.50 Igen, No. 213 “ 10 Lopvi 6341 - do., but mounted for use on dissecting mi- ~ g No. 209 “ 10 Iopza Croscopes..........--.55% No. 1682 “ 6.25 Iqgew No. 205 “ 10 Logfo No. 167a “ 6.25 Iqgup No. 201 “ -10 Logov . No. 166a “ 6.25 Ighoa 6301 do., but in perforated rolls. .... No. 217 roll 95 Iorfn No. 165a “ 6.25 Ighyg No. 209 “ 1.00 Jorih * | 6342 Magnifier, Hastings Aplanatic Triplet. No. 205 “ 1.10 Iormz No. 173 “ 9.00 Igioz 6302 Labels, Dennison, gummed, with red border. No. 172 “ 9.00 Iqiun No. 2004 box _—.20 a No. 171 “ 9.00 Igjab No. 2007 “ 20 Tosig No. 170 “ 9.00 Iqjif No. 2001 “ 25 Tosmy 6343 do., but mounted for use on dissecting mi- No. 2005 * -30 Lospr CYOSCOPES.. 0.2.60... ee No. 172a “ 8.75 Igler No. 200 35 Tostb No. 171a “ 8.75 Iqlow 6303 Labels, Dennison, oval, gummed, with Wa 6344 Magnifier, tripod.....................08. a 15 Iqobu border.............---055 No. 241 “ 10 Totti 6345 “ Watchmaker’s No. 144. 3to ey i = Iqpav No. 239 “ 10 Lotxa 2to3X “ 1.35 Igpos No. 229 “ 10 Joufk 6346 do., but with two lenses. ...... 4X & 7X “ 1.75 Teal 6304 do., cireular, plain white....... No. A83 “ 25 Touzv 6347 Magnifier, Watchmaker’s No. 14444 10K “ 1.50 Iqsud No. A85 “ 30 Lovdn 6348 do., No. 144-LP, with head spring 5x “ 1.75 Iqudk 6305 do., rectangular, plain white.... No. Al8 “ 40 Iowas é 2.5X “ 1.75 Iquiy 6307 Labels, micro slide, blue border... 22mm “ 12 Iowpn 6349 do., Achromatic, No. 144-C.... 5X “ 3.35 Iquap 6308 do., rectangular be cnx Sior ey aeteovi ns 22x15 mm “ 10 Zozlo 3X 3.35 Iqvom 6309 do., in books of 500..........- 22mmbook .40 Toyfg 6350 Magnifier, Engraver’s No. 146.. 3.5X = 5.25 Iquok 6310 Labels, chemical, printed...............-. “ 50 Lozel 6351 . Linen tester No. 14134 14x44 in. 15 Igyph 6312 “Figures, gummed paper... 0 box 20 Ipaam | 6352 - Reading glass, with handle 2! in. “ 2.25 Irace 1“ 20 Ipadg 3in. “ 2.50 Irahu 2 20 Ipahy 34 in. “ 3.25 Irako 3 “ 20 Ipalg . 4in. “ 3.75 Iranh 4% 20 Ipaoj 6353 a Binocular. ...........00 eee vee " 4.50 Irbez “a 2 “ 2 ee 6358 Mailing case, bacteriological, double se * “a 7“ .20 Ipazn 74x14 in 25 Irebe g 20 Ipbiv 6359 a “Water, double..... 654x234 i in. “ 33 Irdaf ie g ‘20 Ipbuw oa : lle Nasser Bree 434xlWgin. “ 10 Irdsu a 7 636 ; “Typhoid, double.. 334x234 in. “ 25 Irejm 6313 Labels, letters, Ato Z.........-.-----+++- .20 Ipdog : cad tie, te nal 1000 letters in box. . ee “ 250 a 6366 Manometer, mercury, unfilled............. © 12.50 Irewl Ladle, wrought i HOM. ccsinekeee? in. e2. 00 [pa MEASURING APPLIANCES 6318 Lamp, alcohol, brass, with cap. . 402. 2 80 Ipglk ; ; 8 02. 1.10 Ipgyj 6370 Rule, Boxwood, graduated in inches and mil- 6319 do,, but nickel plated.......... 25¢x2in. “1.60 Iphyt HIRAI sc atin 3 a 15 Infpy 45 46 A R TT H UR H. T H O M AS Cc O M P A N_ Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 6371 Rule, Boxwood .............. Gin. ea. — $0.10 Irgki 6472 Specimen holder, Sauveur................- ea. $3.00 Iihwe 6372 do., but of steel............... Gin. “ 80 Irhna 6473 “Magnetic, Sauveur patent. “ 3.00 Ttila 12in. “ 1.40 Irhio 6474 “ Mioim bets con aoe ee past Ae eis a 1.75 Itjen 6373 do., but of heavy steel......... 6in. “ 90 riji 6476 Achromatic objective, 4mm, 0.65 N. A. spe- 12in;* 1.65 Irinz cially corrected. 5. 04s seuss eres : 13.00 Itkri 18in. “ 2.60 Iriin 6478 Achromatic objective, short mount, 32 mm.. “ 10.00 Iémmu 24in. “ 3.30 Irizf 6479 ‘i 16mm “ 12.00 Itocm 6375 Meter stick, wood, graduated in inches and : 6480 ss “ ft 4mm “ 16.50 Itorh millimeters, brass ends..... Imeter “ 60 Irjso 6376 do., but without brass ends.... 1meter “ 50 Irkma 6490 METALLOGRAPHIC CAMERA RSA, 6377 Rule, folding caliper, graduated... 6in. “ 80 Irmaw with arc lamp; for 110 volts......... “185.00 Itprg 12in. “ 1.25 Irmhi 6491 do., but for 220 volts................... “188.75 Itran 6378 “Folding pocket, steel, graduated 6492 Metallographic camera RSM, with 6 volt 12in. “ 1.20 Irnen Mazda lamp and transformer for 110 6379 “— Decimeter, of steel .. 1decim. ‘ 50 Iroau VOlE AxCa nse cuss Be sR ARES “175.00 Tisiw 6380 Slide caliper, graduated in inches and mm 6493 do., but for 220 volt a.c................ “178.75 Itink 3in. “ 4.25 Iront 6494 Metallographic Camera RSP, with Pointolite 6381 Micrometer caliper, 1 inch to 1/1000 inch... “ 8.00 Irpat lamp and resistance for 110 or 220 volt 6382 «25 mm to 1/100 mm.... “ 8.00 Irpzu VOlb Ge Canterncin gine ae matmmenan nme “205.00 Itufa 6383 ss “20 mm to 1/100 mm.... “ 1.50 Irqud 6495 Metallographic outfit; Camera RSA and Mi- 6384 Caliper rule, English and metric scale 2in. “ 60 Irrsg croscope FSM9, with arc lamp and 6385 ‘ Vernier, inside and outside, with resistance for 110 volts.............. “ 434.00 Ituxp depth gauge. English and metric scale. 6496 do., but for 220 volts................... “437.75 Itwis 160 mm “ 4.00 Irshe 6497 Metallographic outfit; Camera RSM and Mi- 6386 “Vernier, inside and outside. croscope FSM, with Mazda lamp and 10cm to0.l1mm “ 2.00 Irtiz transformer for 110 volt a.c......... “424.00 Itcyk 6387 “Outside, with spring nut.. 4in. “ 1.10 Irueg 6498 do., but for 220 volt a.c................ “427.75 Ttynf 6388 “Inside, with spring nut. . . 4in. “ 1.10 Trust 6499 Metallographic outfit; Camera RSP and Mi- 6389 “Outside, plain. .......... 4in. “ 60 Irvuy croscope FSM9, with Pointolite lamp 6390 “Inside, plain. . ; 4in. “ 60 Irxiv and resistance for either 110 or 220 6391 Taper gauge, 17¢in. in 1 1/64ths. . Rca “ 5.00 Iryec VOlbids Cecawsceaines Pasees Beene ee “454.00 Itzne 6392 «27mm inlg mm............ “ 5.00 Iryxp 6500 Metallographic outfit, small inverted, with 6393 Measuring cones, grad. to 0.1 mm. 1-15 mm “ 1.00 Irzzk 6 volt 108 watt Mazda lamp and trans- 15-30 mm “‘ 1.50 Isada former for 110 volt a.c...........-. “330.00 Iuajk 6394 Tape measure, pocket, steel, English and 6501 do., but for 220 volt a.c............0055 “333.75 Iubab metric scales; in spring case 36in. “ 1.00 Isarx 6502 Metallographic outfit, small inverted, with 6395 do., but of linen PAPC es 5 tssec ts 36in. “ 40 Isbpa Pointolite lamp and resistance for 110 72in. “ -70 Isbvo OM220; Volt de Cu, onc ce eaan ee vauaen ® “350.00 Iubum 6396 do., but of steel............... 36in. “ 1.10 Iseyh 6506 Metallographic outfit LL, with 6 volt 108 72in. “ 1.70 Isdin watt Mazda lamp and transformer for 6400 Melting point tube, Thiele-Dennis, Pyrex... “ 1.50 Iseho THO Volt as Cit Laue deere 560.00 Iucnz 6401 “Pyrex glass...... af 1.25 Isewj 6507 do., but for 220 volt a.c.............--. “563.75 Iudld 6404 = Mercury still, Hulett............ 500 ml “ 11.00 Isfwi 6508 Metallographic outfit LL, with Pointolite 6406 Mercury vapor arc lamp, Nutting, filled.... “ 15.00 Isgul lamp and resistance for 110 or 220 volt 6407 do., but without mercury. .............. as 7.50 Ishvi Os Gecac hahah canteiounenead beneligene mes “580.00 Iuecu ; : 6510 Metallographic camera GSA, with arc lamp 6410 METABOLISM OUTFIT, Newcomer modi- : "and resistance for 110 volts......... “« 390.00 Iuesn fication........ eee e teens “313.00 Isima 6511 do., but for 220 volts................... “393.75 Iufmz 6411 do., but with calibration curve for the bur- ; 6512 Metallographic camera GSM, with 6 volt Ctl eacdon heb eure clan ecies eee “328.00 Isjax Mazda lamp and transformer for 110 6415 Gas bag, Douglas No.1......... 100 liters “‘ 68.00 Iskig TOlEaOR iret ae oa a notte, “ 380.00 Iughi 6417 Face mask, adult size..................--5 i 12.00 Isisk 6513 do., but for 220 volta.e................ “383.75 Iugyz 6419 Flutter valve, Boothby pattern............ is 20.31 Ismth 6514 Metallographic camera GSP, with Pointolite 6421 Double Douglas valve...................- : 20.20 Isnwa lamp and resistance for 110 or 220 volt 6423 Aluminum valve, 3 spigot............... ae S 12.70 Isomu Lee etn oe a ee as “ ~~ 435.00 Iuhsk 6425 Flexible corrugated tubing....... 26x1 in a 9.50 Ispar 6515 Metallographic outfit; Camera GSA and Mi- 6426 do., but 12 in. long..... hor Lee nn 3 6.00 Isqiy : croscope IL9, with arc lamp and re- 6427 Wail board, for gas collecting tubes........ if 2.00 Issbm sistance for 110 volts............... « 90.00 Iuije 6430 Metabolism apparatus, Benedict, portable; 6516 —do., but for 220 volts................... “693.75 Iujid for 110 volt d.c. or 60 cyclea.c..... “ 250.00 Istan 6517 Metallographic outfit; Camera GSM and Mi- 6432 Thermometer, only, for No. 6430. 10- 50°C. “ 2.00 Iswam croscope IL9, with Mazda lamp and 3 transformer for 110 volt a.c......... “680.00 Iukic 6450 METALLURGICAL MICROSCOPE IL...“ 260.00 Isuoj 6518 —do., but for 220 volta.c................ “ 683.75 Iulej 6451 ILO“ 305.00 Isviv 6519 Metallographic outfit; Camera GSP and Mi- 6454 —_ Illuminating device for IL Microscope...... “14.00 Iswuv croscope IL9, with Pointolite lamp 6455 Connecting adapter...................... x 3.50 Isyhu and resistance for 110 or 220 voltd.c. “ 735.00 Iuluc 6458 Microscope, Metallurgical, FSM1.......... 198.00 Isyyl 6459 < es BOM cca ccaueue «249.00 Itaca 6530 Cone shape adapter...................... ae 50.00 Iumlu 6464 Vertical illuminator, with plane glass reflector “ 13.25 Itarv 6531 Specimen table......................0... ee 45.00 Iundj 6465 do., but with side tube carrying condenser 6532 Clear glass reflector...................... ee 7.50 Iunua and iris diaphragm................. ne 22.25 Itboa 6536 Arc lamp unit, with hand feed are lamp, but 6466 Vertical illuminator, with mirror semi-circular without resistance.................. ne 74.00 Iuomq TeflectOnukeed na awera Gels samek asa e 13.25 Ticyf 6537 Mazda lamp unit, with 6 volt Mazda lamp, 6467 do., but with side tube carrying condenser but without resistance or transformer “ 66.50 Iuphz and iris diaphragm................. “22.25 tego 6538 Pointolite lamp unit, with Pointolite lamp 6468 Vertical illuminator, complete with. plane and resistance for 110 or 220.voltd.c. “ 104.50 Iupyq glass and mirror reflectors, and side 6539 Arc lamp attachment, without resistance.... “ 14.00 Iugyp tube carrying condenser and iris 6540 Mazda lamp attachment, without resistance. “ 8.50 Iurkr diaphragm: nc 'nuwe unitate seers “25.75 Iteaf 6541 Pointolite lamp attachment, with resistance 6470 siteehiantcat Hane for Microscope FSM..... 42.00 Itgle for 110 or 220 volt d.c............-. . 47.50 Iuryo 47 A R T H U_ R Hs T H O . M A _S Cc O M P AN Y ee Cod . 0. Description Size Uni aod Cat. 6542 Pointolite t Price Word No. D Code 6543 aon bulb; only; for 220 volt..... ea, $8.50 Tush | 6612 MICROSCOPE IS 8 eee ie 544 Ankoma tacatnitiee, Al-unniapein volt..... - 8.50 Iutml 6613 a ea. $132.00 Ixhmr G45 Double plato holder, for 334x434 mab plats, | ets a ae “8.00 Fae without reducing kits ac e . “ sé do, Without Tetuing its... is 1.75 Inuaj | 661 « ial tae 6 do., ae inch plates, without reducing see d ae “ vee Ixnaj dag’ Shay yen ae SS " 15 Iuvxm 6619 “ it 00 Ixohu Ee a ne “2280 el G48 Double ole, fo inch pais, ie OE | 920 Fe out reducing kits... . : a ‘ Bod neg cao 2.00 Iuzip | 6624 “ 205.00 Ixtuo do., Panera Be for 314x414 and : 6625 “ . a Izume 6550 Double plate holder, for 8x10 inch | sc; {Ba Tumoo | 6626 ¢ «R000 Ean without reducing kits. . ong ae : “28300 Teme 6551 do., but with reducing kits for 5x7, 4x5 and ee ee " “292.50 Teyle 314x414 inch plates. .... detain 4.85 Hee i , 3750 Tass esx Sibel ee eke Ge Me 85 Iuzgr 6640 “ “9600 Tyaf 8x10 inch plates, with reducing kits for pa i “72.50 ipa plates 314x414 to 8x10 inches. “ 7.00 I : “93.50 Iybst 6553 Transformer, for 6 volt, 24 watt Mazda lamp, Te é “138.0 Tyga 110 volta.c....... cn, oe i “_APSIO.... “181.00 Ty 6554 do. but for 220 volta.c........------- a qe. | @Chenatoal Mi psa ans 3750 «140.00 Tye Se a Si ta ay 1125 Iibes | 665 eM so tee Ovoltd.c...........0..2. a = © M4... ee a i 6556 do., but for 220 voltd.c................ ii a i ad 6653 Auxilliary stage, for metallurgical work... .. is ae oe 6557 Resistance, fixed form, for hand feed arc sei 6° Miwa aca ae 7 dee a “10800 Zany (Sidi, ieee “815 Inje | 6658 7 eee «19800 Dist ee ee ee Tyjou A + “ roE ar “ 6562 GRINDING AND POLISHING’ MA- Soul ere i ag “12300 Lind CHINE, Sheu fr 110 vol 0 cee TR Ta cycle, a.0........0 0c cece eee ees . ‘ a : 6563 Grinding wheel, alundum, 80P.... 8x34 in. “ va iene nese : . Cp ae C3 “f oa shed 6564 do. but 34 in. thick.....-.............- «970 Tom ~—- | 8666 = Clamp stand KC, only.......... se aon tase 6565 __do., but grade 200-M.......... Bazin « Fag TMS) 6667 Glass plate, square... 300mm “ 6.00 Typ on ee fibre careers 8x84 in. “ 6.00 Ivlua ree Binocular Microscope KN1.............-- “ 118.00 pa lo., but 44 in. thick.............-.... “ : : : , 6568 Polishing cloths, evasion st 10x10in. doz. ey ae eet . ENS. Beh Se “ : 168.00 he 6569 a” Cuwaduck, .. dxidins 175 Ivoks 6671 Preparation stand KN, only............... « 9359 ue 6570 Covered dishes for powder, with brush....... ack 4.00 Tes 6672 Monocular erecting body, only...... HO 27.00 Ti 6572 Combined grinding and polishing machine, 6673 do., but with double nosepiece........... ne 33.50 losses Wysor, single spindle, belt drive.....ea. 78.50 Ivpyo pos Binocular Microscope CAEB....... tees 270.00 ie ij 6573 do. buton base with motor for 110 voltd.c. “ 122.50 fees ioe OMEN aie ycosns “283.00 Tye 6574 do., but for 110 volt, 60 cycle, a. c.. 130.00 Iotez ene i CART puicetis ones «301.00 Tayes Ss Gorieed canine sta gluing seas ; 6677 “ «“ GABI8.. 1... 383.50 Tn Wysor, triple spindle; belt brive, with- 6678 Monocular body tube, only..............- “26.50 Iyzve GUTOR say ass iv anacce es seen To Tite || Poon: een Sree Eee soe «50.00 Ta 6576 Grinding wheel, coarse. . 6x3, in. “ 3.25 I 6686 Dissecting stand - Ripe re ys raat a “ 49.50 Tobe 6577 Medium... Grp im 38 Te | 668 RB gedeeee teen “55.75 ecg 678 Fine... een esniee (tee oH Binootl HA saris 124°50 Tedut oo. & we ape ae i6-4 ae ee Oe 80 Toeme “ < ce “ " “ tr < oe ee eS ee ee G1 Chyna, fag gnde EM | SESE Dinating tnd Sonn RTS. 48800 Tate yerade SEM oo roy | S886 Dissecting stand, Mongeular RMI... © 492'50 Injeb 6582 Polishing disc, of brass iy te | eee RM2 «199.00 T2ki 6583 Cloths, 5in set. “ikea aie: | 6 ee ee 6584 Emulsion bulb, glass with rubber stopper. . = aot | te fn ae RM) 150 Temod 6585 Wooden stand, for 4 emulsion bulbs........ 1.50 Iwegi a « MicroscopeW1...............+. “16.25 Tenis 6586 Rough grinding machine for Le 3 Hi “ : W2o. eee “18.00 Izoli specimens, without motor.........-. a 55.00 Iweuf He “ : WS... 0s eves “20.75 Izoaf 6387 Carbon nam minding belts.-.-Very Coarse “50 wide | 719 Tens older ay eee “27.00 Tegho, cease | 0 ete) grt Seem 8 eer Fine ; - 8p Twinp bie Barnes dissecting microscope a seiglGaetgtnksteat . 5.50 Izuay Very Fine 50 Iwipl 6714.“ “ e dqg iZ a“ MMB. e 3 zulb ie MICROSCOPE a Buse dere stems “60.50 Twofa os THe... see “9.15 Tenif be i a wpe? agen a th on roe ae Achromatic objective, dry, 48mm, 0.08 N.A. “ 6.50 Izuka 6603 7 ore skeen sy : oes sae pe : 3 : 32mm, 0.10 N.A. “ 6.50 Izzid 6042 FRB ss 12850 Tzano | 6721 a eee 6605 ae PIG. ocak oceans “ 441.50 Inbif | 6722 “ i oe oe 6608 “ i eae “64.00 Incuf | 6723 “ iy eam 6609 “ Shs caterea eee “66.50 Ixec “ “ os eae 6610 “ FS6 en ante | aan ae a a que anes ee ots = ; agg OBB Nef es “18.00 Jadan . pasunaordes sper ses : 3mm, 0.85 N. A.“ 13.00 Jadse 48 A R T H UR H . T H O M AS Cc O M P A N_ Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 6726 Achromatic objective, homo-immersion, 6846 Micrometer ocular, 7.5X, with movable scale ea. $13.25 Jeyzl 1.9mm,1.25N A.ea. $42.00 Jaeju 6847 do., but with fixed scale...............- 8.00 Jezsy 6727 e see homo-immersion, 6848 Filar micrometer ocular................... ‘s 42.00 Jhalg 1.9mm fluorite, 1.30N.A...... @ 55.00 Jaewt 6850 Stage micrometer, ruled to 0.1 and 0.01 mm. “ 5.00 Jhazd 6730 Huyghenian ocular, 5X....... it 2.50 Jafnk 6851 do., but ruled to 0.01 and 0.001 inches... “ 3.50 Jhenz 6731 i OE GAIA ai cts fe 2.50 Jagbi 6852 do., but metal, ruled to 0.1 and 0.01 mm.. “ 14.50 Jhibs 6732 i He” STD Reweta 2.50 Jagxp 6854 Micrometer slide, Hausser................ . 8.00 Jhior 6733 : a LOX sae : ae 2.50 Jahml 6856 Polarizer, with one selenite................ i 18.00 Jhlid 6734 a OE VD DIN ches cot ride tee Boe i 2.50 Jaide 6857 “ three selenites. . coro ere 22.50 Jhomg 6738 — Apochromatic objective, dry, 16mm,0.30N.A, “27.50 Jaior 6858 Analyzer, for use above the objective....... “ 15.00 Jhubg 6739 “ 8mm,0.65N.A. “ 36.50 Jajry 6859 e ocular: 5 ovate ox “22.50 Jhupd 6740 fe " “ 4mm,0.95 N.A. “ 50.00 Jakjo 6862 Bulls-eye condenser, on stand. . 38 mm “ 5.715 Jhyew 6741 “ bs “ 3mm,0.95N.A. “ 60.00 Jaldz 56 mm “ 7.25 Jhyhq 6742 : - homo immersion, 3 75mm “ 11.50 Jhyli mm,130N.A.... “ 132.00 Jalsa 6870 Micro warm stage, electric, 110 volts....... ns 16.00 Jhyzf 6743 . ““ homo-immersion, 3 6874 Micro slide incubator, electric, 110 volts.... “ | 20.00 Jiagt mm,140N.A... “ 176.00 Jamhg 6875 Thermometer, only, for No. 6874.......... uf 1.25 Jiber 6744 a “ homo-immersion, 2 6876 Carbon filament lamp, 16. p..... 110 volts “ 50 Jibuk m,1.30N.A.... “ 80.00 Janad 6880 Silverman illuminator, patented, ..110 volts “ 45.00 Jicma 6748 Compensating ocular, 5X... ; .. “. 5.15 Januo 6881 Ke 220 volts “ 45.00 Jidih 6749 aD Re a Ales ake ade nf 5.75 Jaoki 6882 Lamp, only, for above; colorless glass kines a 4.00 Jiecs 6750 S SD PeMOX ara aoe ce sue ts 7.15 Jaozd 6883 “ " Daylite glass....... a 4.50 Jiesl 6751 Mp gh2O OG Weare onthe eee 7.75 Japy m 4 6752 “ “ TEX iene: 7.75 Jaqul 6890 MICROSCOPE, ZEISS, Stand ITICA...... 116.00 Jifos 6753 “ (MOEN ny tras « 6.75 Jarmb 6891 do., but with achromatic outfit and triple revolving nosepiece................. “217.00 Jighg 6756 Paired objective, 55 mm.... .. pair 20.00 Jarza 6892 do., but with achromatic outfit and triple 6757 “48 mm.... a 20.00 Jasov revolving nosepiece................. “309.50 Jihel 6758 oH “ 40mm....... 20.00 Jaild 6893 Zeiss Microscope, Stand IIIH.............. “160.00 Jihve 6759 a $232 MIM voxis eevanes “20.00 Jaucs 6894 do., but with achromatic outfit and triple 6760 a FE SQA MMM a werininaibeateninenatees . 20.00 Jausl revolving nosepiece................. “261.00 Jiija 6761 ve “94 mm water immersion... “ 20.00 Javgo 6895 do., but with apochromatic outfit and triple 6764 = Huyghenian oculars, 50 mm...... or 5.00 Jawgi revolving nosepiece................. “353.50 Jiizt 6765 . : 40 mm. ° 5.00 Jawuf 6896 Zeiss Microscope, Stand IA............... «153.00 Jikag 6766 a se «33 mm. . * 5.00 Jazns 6897 do., but with apochromatic outfit and triple 6767 es s f- SOMM oe Scnnceu 5.00 Jaydm revolving nosepiece................. “346.50 Jikrh 6768 o " 20MM cps ef 5.00 Jaysh 6898 Zeiss Microscope, Stand IB............... “186.00 Jiliz 6780 Demonstration ocular for two observers. .... ea. 36.00 Jazlv 6899 do., but with apochromatic outfit and triple 6782 Substage condenser, Abbe, 1.20 N. A.. os 12.00 Jeabg revolving nosepiece................. “379.50 Jilys 6783 140N.A....... i 14.50 Jearz 6910 Zeiss Microscope, Stand IPhC............. “207.00 Jimmg 6784 * e spans 140 N. A... “ 20.00 Jebkn 6911 do., but with apochromatic outfit and quad- 6785 do., but with iris diaphragm. . ... © 26.50 Jecey ruple revolving nosepiece....... .... “474.50 Jinef 6786 Blue glass disc..................0.00200 0% " 50 Jecyj 6920 Plain revolving vulcanite stage, Zeiss....... “ 11.00 Jinwu 6790 Ultra-microscope condenser, Siedentopf Car- 6921 Large revolving mechanical stage, Zeiss..... ‘‘ 44.00 Jioks dioid type, Zeiss, without accessory 6922 Center housing, Zeiss..................0-. 7.50 Jiozr AP Paratustie dics @ hesiove newness “20.00 Jedpa 6923 Paraboloid condenser, for dark field, Zeiss... “ 20.00 Jipge 6791 Object slide, chamber form, for above. ..... ef 11.00 Jeegs 6924 do., but without diaphragm............. 16.00 Jigec 6792 Holder, for No. 6791..................... 8.75 Jeeun 6925 Paraboloid stops, for Zeiss objectives....... “ AS Jiraj 6793 Cover glass, 0.4 mm thick................. 25 Jefoa 6927 Triple revolving nosepiece, Zeiss........... . 11.00 Jirsy 6802 Dark field illuminator, Spencer, with 6 volt 6928 Quadruple revolving nosepiece, Zeiss....... e 11.00 Jislm lamp for 110 volts; without resistance “ 35.00 Jegho 6930 Huyghenian ocular, Zeiss No. 1, 50mm, 4X. “ 2.50 Jitir 6803 do., but with 4 volt lamp for use on primary 6931 No. 2, 40mm, 5X. “ 2.50 Jiube « or storage battery.................. % 35.00 Jehab 6932 ? «No. 3, 30mm, 7X. “ 2.50 Jiurz 6805 Lamp bulb, 6 volt, for 110 volts........... ns 65 Jehoy 6933 es “No. 4, 25mm, 10X “ 2.50 Jivjn 6806 « «4 & — “& primary or storage 6934 s “« “No. 5, 20mm, 15X “ 2.50 Jivek battery........... a 65 Jeihm 6936 Orthoscopic ocular, Zeiss No. 6, 15mm, 20X “ 5.75 Jixin 6807 Resistance for 220 volt d. c. or a.c......... S 8.00 Jeixf 6937 “No.7, 9mm, 30K “ 7.50 Jiyac 6808 “ 110 volt d.c¢. or a.c........ % 6.00 Jejrg 6940 Achromatic objective, Zeiss ay dry, 36mm... “ 4.75 Jiyoz 6810 Dark field illuminator, B. & L............. 21.50 Jekle 6941 a* dry, 25mm... “ 16.00 Jizet 6811 Funnel stop, for B. & L. 1.9 mm objective... “ -90 Jeldr 6942 a “aa dry, 23. 5mm. “ 11.00 Jizwi 6814 Auxiliary condenser, for dark field illumina- 6943 of & ““Adry, 18mm... “ 8.00 Joaiz GON signs eactereniaala wirannee aie 5.75 Jelvg 6944 He # “ Dadry,4.4mm.. “ 15.00 Joaxs 6820 Nosepiece, double ayOlNinEs saree heater 6.50 Jemmy 6945 ee “DD dry, 4. 4.mm “ 29.00 Jobo; 6821 oe triple revolving... i 9.00 Jenif 6948 % Se “1/7 in. homo- 6822 “e Quick-changing. . nes ee i 12.00 Jeocq immersion... “ 25.00 Jociv 6823 Objective rings, only, for No. 6822. we 1.00 Jeorl 6949 “1/12 in. Fluorite 6826 Immersion oil dropper Ete eet vinR Ge a : ms 2.75 J ephf homo-immersion“‘ 62.00 J. ocxg 6828 Mechanical stage, ModelB......... 5 27.50 Jeqas 6950 Compensating ocular, Zeiss No. 2,83mm, 3X. “ 6.25 Jodnj 6829 Finger os ecg gee ees : 24.00 Jeqyv 6951 No. 4, 50mm, 5X. “ 6.25 Joegxz 6830 Abbe camera lucida, Model A..... “ 14.50 Jerng 6952 i a “No. 6,35mm, 7X. “ 6.25 Joevs 6831 us e “ B............ “— 18.00 Jesem 6953 i « «No. 8, 25mm, 10X “ 8.25 Joflm 6832 os e sf eS iO ee cece 30.00 Jeszr 6954 sf e “No. 12, 16.7mm, . 6833 Camera lucida, Bly...............0..5-5- “36.00 Jeiua TOK. Adee eae. * 8.25 Joggu 6836 Ocular micrometer disc, ruled 5 mmin 0.1mm “ 2.25 Jeumg 6955 ss x “No. 18, 12.5mm, 6837 do., butruled in 0.5mm squares.......... sf 3.25 Jevef DOK vee Fades. “ 7.50 Jogzi 6838 do., butruled in 1 mm squares...... Ker, 3.00 Jeowu 6957 Apochromatic objective, Zeiss dry, 16.2mm.. “ 31.00 Johnf 6839 do.,butruledto5mmin0.05mm......... “ 2.50 Jewks 6958 8.3mm... “ 41.00 Joidz 6840 do., but ruled to 10 mm in0.1mm..... ee 3.25 Jewyp 6959 ef e “ “43mm... “ 53.00 Joisu 6842 Ocular micrometer disc, Whipple. . ei 6.25 Jexre 6960 is ft “ « 99mm...“ 63.00 Jojio 6843 Ocular micrometer disc, with ruled circle 8mm “ 3.50 Jeyfa 6961 “ i “ Omm..... “ 125.00 Jokin A R T H U _ R H. T H O M A _§ Cc Oo M P A N Y Cat. Code Cat. Cod ‘ode No. Description Size Unit rice Word No. i Description Siz ae Apochromatic objective, Zeiss gery ae baa yes 7024. MICRO COVER GLASSES, Red Label, ete cee ened : i Sf 82mm" $8.00 Joma liana Needs ie i » 1 thi : 50 Jups 6966 Ultra-microscope outfit, Zeiss, with are lamp nee ee ie j alana aur aa ete ung ih A i ne (Oe rig pele os “253.70 Jonnz No. 1 ee Pau ae 0., ut or 220 volts................... “256.95 Joofp p ee a at deaye 6968 Ultra-microscope, OMY ses ond ei haiti Gbensals 189.00 Jooso no ; ao a ene ° 0. ic .3 af 6970 MICRO LAMP, 6 volt, 24 watt, with spher- No.1 thiknes bee2mm "220 Jus ical condenser, and transformer for No. 1 thickness. 43x50 mm “ 2.20 Jurpf Gm do, tut win ronlornar for vibe «eee ee No. tines 220mm "120 Jun 6972 do but with resistance for 110 volt d.c., “2480 Jorae No.2 themes: 2:52 mn “120 Tape Gin itches esis 8S Ne hoes eft "1 Ya : : : cae ; i mm ‘ condenser, and transformer for 110 No, 2 thickness, 22250 mm * 12 Tafy 6815 do, but with tansiormer for 330 valba-c.* S880 Jone No. hina. 23mm “120 Jue 6976 do., but with resistance for 110 aralt ta es an Toe No. : thickness. a Pt Tut ll ee a vid resteane for 220 volt d.c... “ 39.75 J ougm Ne. ; une a Tet Tes cro lamp, 6 volt, 108 watt, with doubl os ickness. 35x50 mm “ He convex condenser, two Daylite bass, No. 2 thickness. 35x62 mm “ 1.70 ae and transformer for 110 volt a.c..... “ 43.50 Jovi , No. 2 thickness. 43208 on 170 Juiemg i: deed Dees ee No.2 thicknes, 9x70 mm “1.70 Junga 6982 Micro lamp, 6 volt, 108 : eee rae Dele els, and 7030 MICRO SLIDES, Red Label, 1 mm thick, 1 3x1in. sue ab Sane aoe i a oles: Chee e eacts : 55.50 Towng 7031 do., but 114 to 2 mm thick......... . a 30 pe Hee re sais aa ee ma ea on aoe a do., but 1.45 to 1.55 mm thick........... doz. .36 Juwts + ae ee ae, iitars fom, with bine sad s 2 33 do., but 1 mm thick........... 3x2in. gross 3.20 Juzlt oni gaa DAL a 6.00 Joyom Or ala i santas white, BlueLabel 3x1 in. “ 1.60 Juygr ; for 110 volts.......... : ier i i a see but for ne pe Pakiiee sey agee & kt 10.25 Jozdi : ass. : : ee ‘ tt a a ea, 10 Juyzi ae: cee a with Daylite . 7041 do., but two concavities........ 3xlin. ‘10 Tin ee: Aicmutfe Woy... a‘ 1128 war Oe hee eae rere eee 6990 Resistance, for 15 watt, 110 volt c: oe iti ee ae ed ee Pp 7043 do., but two concavities....... 3xlin. “ 15 Jyark i Tots ay oe ea © eae ae i , 110: ek f eep, flatbottom.......... i 6992. Micro lamp, chalet form, one window; for 110 : iergga 7045 do., 12 can ee ee ae pte nea win wemeredee ede eed ‘ 00 Jucmi 2mmwide............... 75x25 of Jl ao a er ior es ee Gti cose Bes : 22.50 Judew 7046 =Micro ane slide, with cell 15x3 mm thea seid ee oe fee e ae nodes lows; 110 volts..... : ie UUM om SOD eae eos aaa gen 76x26 mm “ 35 Jydaq ane Do Vache . eioea ree mecseaea ela eats : a oe 7050 Micro side cell, square.......... 22mm “ 20 Jydon G67 Walsboch gua mantis, refon, sized.“ 25 Jafar | Baer is mn 2 gel 7000 Micro lamp, hand feed arc, with resistance for are ss Dae Li0iwolbetiesaca vicecauda view annn pace “32.25 Jugif ie eg 7001 do., but with resistance for 220 volts..... “ 36.00 Juheg ee « oe 7002 Micro lamp, hand feed arc, Spencer, with re- ae EE i os It sea at p : ig nie et ee eee Box, Monel metal.............. a 1.60 Jyfku 7003 —_do., but with resistance for 220 volts... . “ 35.50 Juiel | 7058 8 « ae Pillsbu aie ‘25 slides bem to 1004 Daylite glass and adapter, for No. 7002/3... “2.28 Juigm | 7089 9 © of wood... ALi Cage 7006 Micro lamp, hand feed are, Zeiss, with resist- eee ye Roe a Pap ance for 110 volts ................. 33.75 Jujhe x tel ‘ i ae 7007 do., but with resistance for 220 volts....... a 37.00 Juken 7060 “« «cloth covered, with lid ea. 10 Thi : 7020 MICRO COVER GLASSES, Red label, 7062 ©“ “ ‘yay, cardboard, for 20 slides..." 30 Jyjbt square....No. 1 thickness. 12 mm oz. 1.80 Jukwy : . i enon sds kee No. 1 thickness. 15 mm “ 1.50 Julag 7066 Micro slide cabinet, with aluminum trays, ; No. 1 thickness. 192mm “ 150 Juldk capacity 1000 slides................ «55.00 Jykaj No. 1 thickness. 22mm “ 1.50 Julge 7067 do., but capacity 2000 slides............. “110.00 Jykym No. i thickness 250m © 1.50 Juljy 7068 do., but capacity 3000 slides. . “150.00 Jylim No. 2 thickness, 12 mm “ 1.50 Julnp 7070 Micro slide cabinet, unit system, of fae ca- No.2 thidaes. leant © 1.10 Julub ___ pacity 500 slides Koaidnbes asaateebitstinnnGasace “27.50 Jymez No.2 thickness. 18mm “ 1.10 Julyt 7072 = Micro slide cabinet, Minot, of metal, capacity No. 2 thick on 2 mae : 110 Jumbn C20 SOS 5 2s sears exarcnes oes 8s «42.00 Jymug 0.2 thickness. 25mm “ 1.10 Jumeh 5 : j We? ica ee EM eee peepee ete ge No. 1 thickness, 15mm“ 1.90 Junbm for lO volba.@. tsssssesscs,, % 5700 Juke No.1 thickness. 18mm“ 1.90 Juneg | 7076 Micro projection outit, with 6volt; 108 wate = No. 1 thickness. 22 mm 1.90 Juniy Mazda lami aad transfor vor f No.1 thickness. 25mm“ 1.90 Junol LOG a aes oan @ 300. Taner volt, 60 cycloa.c.......... eee 75.00 Jyocb Ao ee a ‘ 1507 7077 ~~ Base board, only.............-.000eeee eee “10.00 Jyopa Ne. ° ne 18 a G 150 pe 7078 . Light shield, only, on support............. “ "650 Jypdy Ne 4 ee a mm 150 ofl 7079 = Mirror, only, with clamp.................. ¢ 4.25 Jyptr 0. 2 thickness. mm wofe 7080 Drawing shield, pyramidal............... s 1.75 Ji No. 2 thickness. 25 mm 1.50 Juoiz : ee ee Ngee 7024 —do., rectangles. No. 1 thickness. 22x30 mm “ 1.50 Juoyg | 7082 MICRO - PHOTOGRAPHIC CAMERA . “cs , No. 1 thickness, 22x32 mm 1.50 Jupet Model K, without shutter; for 34x44 1.50 Jupiu in. plates ihphaticheis lhebeherncens 35.00 Jyrho No. 1 thickness. 22x36 mm “ : 49 A R T H U R H. T H O M A i) e O M P A N Y Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 7084 Micro-photographic camera, Model H, with- 7151 Section razor, flat concave, 75 mm blade... ea, $2.00 Keatu out shutter; for 4x5 in. plates........ ea. $75.00 Jyrxh 7154 Microtome, automatic sliding, without knife “ 115.00 Kebhs 7085 do., but for 5x7 in. plates............... 80.00 Jysqu 7155 do., with shanked knife 165 mm......... 129.80 Kecex 7086 =Micro-photographic camera LDA, with arc 7156 Microtome, Minot rotary, with three object lamp and resistance for 110 volts.... ‘ 285.00 Jytgo discs; without knife................ “132.00 Kecvo 7087 do., but with resistance for 220 volts..... ‘© 288.75 Jytzb 7157 do., with knife, handle and honing guide.. “ 144.80 Kednd 7088 Micro-photographic camera LDM, with 6 7158 Clamp, only, with plane post, for 1 inch blocks “ 5.50 Keegr volt Mazda lamp and transformer for 7160 Microtome, Minot simplified rotary, with TIO: Voltas Ge acs eaten eine ese “275.00 Jyuld three object discs; without knife..... o 82.50 Keexi 7089 do., but with transformer for 220 volt a.c. “278.75 Jyuye 7161 do., with knife, handle and honing guide.. “ 92.85 Kefme 7090 Micro-photographic camera LDP, with Point- 7162 Clamp, only, with ball post, for 1 inch blocks “ 6.00 Kegif olite lamp and resistance for 110 or 220 7166 Microtome, precision rotary, Spencer, with VO] bd Cis eect sees one a “300.00 Jyurp object discs; without knife.......... “166.50 Kegzc 7092 =Micro-photographic camera GPVA, with arc 7167 do., with knife, handle and honing guide.. “‘ 180.00 Kehoxr lamp and resistance for 110 volts..... “519.00 Jyxaw 7168 Microtome knife, plain, for No. 7166, 110 mm ‘“ 9.50 Keidt 7093 do., but with resistance for 220 volts..... “522.75 Jyyav 7169 do., with handle and honing guide....... 13.50 Ketpu 7094 + Micro-photographic camera GPVM, with 6 7170 Microtome, Minot precision, without knife.. “ 275.00 Kejew volt Mazda lamp and transformer for 7171 do., but with 315 mm knife............. “300.00 Kekax T1OVoltiantnc iio, Benn a tsless “509.00 Jyysk 7172 + Microtome, Minot precision, complete outfit “ 339.50 Kekwe 7095 do., but with transformer for 220 volta.c.. “ 512.75 Jyzka 7174 ~~‘ Tilting knife clamps...................... pair 13.50 Kella 7096 Micro-photographic camera GPVP, with 7175 Object clamp, Zabriskie.........100x80 mmea. 20.00 Kemer Pointolite lamp and resistance for 110 7176 = ~=Microtome knife, Minot......... 315mm “ 25.00 Kemve Or 220 Volt ditiseceic evans ota “539.00 Kaaeh TLGk Glass platez::2.42) coke ance ees ees = 5.50 Kenly 7100 Microscope, photomicro.................. “174.00 Kaate 7178 + Diamantine powder...................... bott. .50 Keoel. 7101 + Reversing mirror, for No. 7100............ 18.00 Kabdiy 7102 Projection ocular, BS Ae mecan elie eounee . 9.00 Kaciz 7182 MICROTOME KNIFE, plain, in case 7103 5X. s 9.00 Kaczs 90 mm ea. 6.35 Keogm 7110 Micro Tessar objective, in ‘photographic Jens 125 mm “ 8.80 Keove style mount............. 72mme.f.“ 44.00 Kadoj 165 mm “ 11.40 Keozu 7111 do., with society screw........48 mme. f. “ 36.00 Kaedf 7183 do., with handle and honing guide, in case 7112 do., with society screw........32 mme. f. “ 36.00 Kaerc 90 mm “ 10.35 Keppn 7114 ~=Doublet focusing glass.................... e 5.00 Kafec 125 mm “ 12.80 Kepud 7115 Achromatic focusing glass................. Hi 10.00 Kagaj 165 mm “ 15.40 Kegej 7116 Ray filters, Wratten & Wainright “M”..... set 14.00 Kagym | 7184 Knifehandle, only, for above knives. . : 2.25 Keret 7117 Photographic plates, Wratten & Wainright 7185 Honing guide, only, for knife..... ‘90 mm “ 1.75 Kerub PENG eon siege SAY ok Mabon 314x414 in. doz. 80 Kahnh 125 mm “ 1.75 Keryt 4x5in. “ 1.10 Kahrz 165 mm “ 1.75 Kesbn 5x7 in. “ 1.80 Kahor 7186 a «No. 7145 knife. .... a 1.75 Kesse 8x10in. “ 4.00 Kahyl 7187 ef « «© No. 7168 knife... .. is 1.75 Ketls 7188 Microtome knife, shanked, in case 90mm “ 10.10 Keuhz 7120 MICROTOME, simplified clinical, with ob- 125 mm “ 10.90 Keulr ject clamp; without knife........... ea. 47.00 Kaing 165 mm “ 14.80 Keuok 7121 do., with knife, handle and honing guide.. “ 57.35 Kajbe 7190 “ “Outfit, consisting of Minot 7122 Microtome, simplified clinical, with CO, freez- knife, glass plate and diamantine ing attachment; without knife....... “ 53.50 Kajur POWERS ¢ Pace covey Menkes evaded “29.35 Kevga 7123 do., with knife, handle and honing guide.. ‘ 63.85 Kakug 7192 Safety razor blade holder................. a 6.75 Kevar 7124 ~Microtome, simplified clinical,complete outfit “ 70.85 Kalio 7193 Hone, yellow Belgian............ 10x21 in. “ 9.00 Kewjt 7126 s medium clinical, with object 7194 “Blue-green water.......... 10x24 in. “‘ 2.00 Kewws clamp; without knife............... “77.00 Kalzf 7195 Razor strop, Emerson’s elastic............. e 3.35 Kexnj 7127 do., with knife, handle and honing guide.. “ 87.35 Kamru 7196 Block strop, Coarse, red finish............. ¢ 3.50 Keyit 7128 | Microtome, medium clinical, with CO, freez- 7197 “Fine, black finish............. He 3.50 Keyxo ing attachment; without knife....... a 83.50 Kanjk 7198 = Strop dressing............0... 20. cece eee box 30 Keznh 7129 do., with knife, handle and honing guide.. “ 93.85 Kaoab 7130 Microtome, medium clinical, complete outfit. ““ 100.85 Kaona 7132 Microtome, automatic clinical, with object MILK TESTING APPARATUS clamp; without knife............... ‘a 87.00 Kapby . 7133 do., with knife, handle and honing guide.. “ 97.35 Kapul 7208 = Milk Tester, Babcock........... - 2 tube ea. 7.50 Khagp 7134 Microtome, automatic clinical, with CO, 4 tube “ 8.75 Khakh freezing attachment; without knife... “ 93.50 Kagqye 7209 do., but enclosed.............. 6 tube “ = 19.50 Khaye 7135 do., with knife, handle and honing guide.. “‘ 103.85 Karma 8 tube “ 21.30 Khebo 7136 Microtome, automatic clinical, complete outfit “ 110.85 Kaset : 12 tube “ 23.00 Kheep 7210 do., enclosed, electric, for 110 volt d. c. or 7138 Microtome, automatic freezing, Spencer, with Hote ca tee hai danas 8 tube “ 67.50 Khesm freezing attachment; without knife or 12 tube “ 69.75 Khevg object clamp Free mee tans “83.50 Kasui 7216 = Milk test bottle, 8%,18 grams ............ doz. 3.00 Khiid 7139 do., with knife, handle and honing guide. . “ 95.50 Katno 7217 Cream test bottle, 50%, 9 grams .......... nf 4.80 Khive 7140 Microtome, automatic freezing, with object 7218 “30%, 18 grams ......... o 4.00 Khmiz clamp; without freezing attachment 7219 Butter test bottle, Hortvet, 9 grams........ ea. 50 Khocj OF KMEG. oc sascesn dain Vege d Saree eee es 73.00 Kaufl 7220 Skim milk bottle, double bore, Wagner, 7141 do., with knife, handle and honing guide.. “ 85.00 Kauwe grad. to 1/20% doz. 12.00 Khopi 7142 Microtome, automatic freezing, complete 7221 do., but graduated to 1/100%, ben ent oie nee 12.00 Khroh OUbE bs sce dar a arson canbens ssenie 98.50 Kavrl 7222 ~=©Acid measure...............0.4. 17.5 ml ea. 15 Khuka 7143 Object clamp, only, for No. 7138........... oe 3.00 Kawgh | 7223 “ Burette, for twenty-five 17.5 ml charges. * i 4.20 Khuzi 7144 Freezing attachment, only, for CO,........ n 13.50 Kawue | 7224 Pipette, Babcock milk, to deliver 17.6ml..... 35 Khyoa 7145 Microtome knife, 110 blade, for No. 7138... “ 8.00 Kaxky 7225 “~~ cream, to deliver 18 ml..... “ 35 Kiaco 7146 do., with handle and honing guide....... se 12.00 Kayhd 7226 ¢ ss Automatic...... 17.6 ml “ 3.30 Kiaow 7148 Object clamp, only, for Bausch & Lomb clini- 7227 ~~ Pipette, automatic, with rubber bulb for filling cal microtomes.........-..-+5+-0-5 Me 7.00 Kaywy 17.6 ml ea. 2.90 Kibay 7149 Freezing attachment, CO,, Bausch & Lomb: “ 13.50 Kazlu 7228 Combined acid bottle and pipette. 17.5 ml “ 6.20 Kibyb 7150 Microtome, hand, B. & L., without knife... “ 10.00 Keaez 7230 =-Milk testing set, Holt.................... uy 4.50° Kicwe 50 A -R T H U eR H. T H OF M A S§ C Oo M P A N_ Y Cat. Cod G No. Description Size Unit Price Word Nee Description Size Unit Price Wand: 7232 aii ach Ny Ye Board of Health, without aa ig ea Re 7309 —-Pestles, only, porcelain, for mortars 65 mm ea. $0.12 se OMELET. 62. eee eee eee ee eee 7 A J 80 mm 20 mugl 7233 do., but with thermometer.............. 5.00 Kied , 7234 Lactometer, Quevenne, without thermometer “ 1.70 Kielt_ ; no i eB a us ie a 210 mn with pusonometee saan “ on ie 150 mm “ ‘70 Kmutk : meter, specific gravity............... “ 19 Ki “ ? a Slide rule, Richmond, original form........ & 6.00 me, A “ a sane Improved form... ... a 15.00 Kihnr “ E 7240 Balance, foreion) ¢ cream nt est age Epos : an Keg 7312 Mortars, stoneware, “Wedgwood,” with sere ottle “ A tig, estles. 2... eee ce No. “ 00 7242 += Fat extraction tub: Rohri ith hol cca “34.00 Kiilo . No. oO 125 Race ex ion tube, ig, with hole in side No. 1“ 1.55 Knadi OF NGC eis eirag vive dae ye sealer ets “ 3.50 Kija g 7243 do., but without hole i in side of neck...... es 3.10 Kin ne q i oa peed 7244 Fat extraction tube, Réhrig-Biesterfeld.... . a 3.80 Kikoy No 7 “ 4.30 Knasd 7246 Sediment tester, Wisconsin type........... “15.00 Kilol No. 9 “ 640 Knazt 7247 ~— Cotton filters, only, for No. 7246........... 1000 4.35 Kimhz No. 12“ 10.50 Kneak Re | MODELS Mane; Keb uiieecet S000 Bag | See Fone | ee 7252 i Valence, Nead’s.............-- : 8.00 Kinnl No. 1“ 59 Kaur Tass et Continuation fNout24 “ 12.00 ioe oo ee 7260 Molecular weight determination apparatus, No 7“ 1.60 Kniig eckmann, freezing point........... ea. 22.00 Kipfa c “ d . 7261 Metallic cover for cooling jar. . “450. Kigit ae ie ae i ben, wi outlet........ 7 sad feat 7318 Mortars, Iron, with pestle........ L-pt. 95 Kniso 7264 Freezing tube............... ee « 190 Kiswo ‘ape wu yas 7265 Sulphuric acid tube..............0-.----. “ 1130 Kitlk 36h ~~ 280 Knial 7266 Stirrer, platinum......................05- “ 5.00 Kiudz ; ae “425 Kniyi el cea 1) cr : oi a 7320 Mortar, Spiegel, of forged tool steel ........““ 20.80 Knofq 7269 Stirring ring, for cooling maictireke oe: «(gg Kiofu 7322 Tron, Buck............- AG in. a uy p SAUL COUIIIS DUAUULU Le. ee ee ee 4 af é jn. 6 A noy 7270 Filling pipetto.....6..0..0000ce0:000ee “ 1.20 Kizac | 7324 = Diamond, Leeds......... 231mm“ 3.10 Krami 7272, +Thermometer, Heidenhain................ 12.00 Kiyab 7326 “ « "Plattner; pestle 15 mm “ 5.25 Kreac 7273 do., but with Bu. of Standards certificate. . 24.00 Kiyna 25 mm “ 7.30 Kreeu 74 A thermometer. . . . . —20to +40°C. “1.50 Kizes 7328 “Agate, with agate pestle. 35mm“ 3.25 Kreun 7280 aaa apparatus, Beckmann, for . ‘i eT 40 mm “ 3.50 Kreth bbe saddewnis ema apes y i 7281 ~~ Boiling polar te, onl: brn fittings....... re a a a a “ ‘2 ee 7282 Steam jacket, only, with fittings. ..... mug 3 ‘Dp “ : . 7284 Molecular weight apparatus, Menzies “ 10.00 Klepk ie aa ii i so Knee 7288 Boiling point apparatus, Cottrell...... “30.00 Kihyp 100mm “ 12.00 Krikk 7290 McCoy...... a 5.70 Klimn 6 ; 7292 “ “e “ Jones & 5.25 Kllea ie s oe oe Lee LE RS 120 mm 7 rirp 7300 MORTARS, Glass, with pestle... 2ozs. “' 45 Klain’ | 7339 MOTOR, Water, to attach to faucet. ...... “ 525 Krock 4 ozs. | a His 7332 “or steam or compressed air “". 9.70 Krosk pS sa 2 130 Klos. 7336 “Electric, i primary or storage ‘ , z 0s “ 00 Krrys 7301 Pestles, only, glass, for mortars. . . 2 ozs. 16 Klugn 7338 “ “ Constant speed, for 110 4 ozs. © 16 an volt d.c.............. “ 100.00 Krunl aoe ae Klupy | 1339 do. bub for 110 volt, 60 el, a Cao “100.00 Krybg . 7342 Motor, electric, with grinding and polis! g i tside, with pestle attachments, for 110volts........... 34.50 Kryrz SS ea eee 66 mm ie 38 Klybt 7343 ‘Polishing head, only, for belt drive c hvapeueto e 7.00 Ksajm 80 mm “ 66 Klyen 7344 Motor, electric, slow speed; 110 volt d.c..... “28.00 Kseby 110 mm “ 1.00 Kiyjd 7346 “ Cenco friction drive, for 110 ; 130 mm “ 1.50 Klynu WOME di Gis cairo eivoie eatiewa contests «31.00 Keegt 150 mm “ 2.10 Klygo 7347 do., but for 110 volt, 60 cycle, a.c........ “ 31.00 Kskya 175mm “ 2.90. Klytt 7348 Flexible Shaft for Nos. 7346/7 motors .....,. “ 3.00 Ksiot 200 mm “ 3.80 Kiyza 7350 Motor, electric, 1-R single phase induction, 260 mm “ Ae Kmadl ‘i , 110 or 220 volts.......... a y E - Se an . 65 “ 15 Kmate Diiidc cd vctucne eal pM 2 eee Be eae 4 Tl. ot Sue 7205 Pestlos, anly, poreslain, formortars oo ah Kmawy | TESZ dss secs ceeesscceeeeee {HLP.“ 114.00 Keunl 110 mm “ 30 Kmean | 7353 Oia scatcne es eirerne recent atone 1H.P.“ 124.75 Ksynj 130 mm “ 45 Kmedh | 7354 CO vier futon os tate alae ose 2H.P.“ 173.50 Kuale 150 mm “ ‘10 Kmehz | 7356 Motor, electric, split phase induction, for 110 175 mm “ 90 Kmelr volt, 60 cycle, a.¢......... 120H.P.“ 25.00 Kubaz 200 mm “ 1.10 Kmepi 7357 do hudhdabluer nay eau noon weet es E . a / 260 mm “ 1.30 Kmeta | 7358 Distis catia eo ween d Nemes nv sientts : : 00 Kucma : tat ide: ” . 7360 Motor, electric, ventilated type, direct cur- 7308 = Mortars, ae glazed inside and nae 50 Kmiln ‘rent, 110 volts.......... if 1gH.P.“ 81.75 Kudif . I) Dee eae eeapooree 80 mm “ 86 Kmiog | 7361 do., but 220 volt d.c.......... YH.P.“ 81.75 Kuebu 110 mm “ 1.30:'Kmisy | 7362 do., but 110 voltd.c...... .. 4HP.“ 104.75 Kuety 130 mm “ 1.95' Kmiym | 7363 do., but 220 volt.d.c.......... =. H.P.“ 104.75 Kufrm 150 mm “ 2.75 Kmoev: | 7364 do., rent but 110 volt d. c.. 1H.P.*‘ 110.82 Kugka 175 mm “ 3.75 Kmohp | 7365 do., but 220 volt d.c.......... 1H.P.“ 110.82 Kuhid. 200 mm “ 5.00 Kmolh | 7366 do,, but 110 volt d.c.......... 2H.P.“ 156.50 Kuhay 260 mm “ 6.50 Kmooa | 7367 do., but 220 volt d.c.......... 2H.P.“ 156.50 Kuimu 51 A R TT H U R H. T H Oo M A §S Cc O M PA N Y Code Cod Cat. oe Description Size Unit Price Word No. ae riaelneaae Rae ea aes Price Word 7370 Motor, electric, two pole ventilated type, di- ea. ; 7470 jeldahl distilling apparatus, Folin modifica- rect current, 110 volts..... ‘ep ae iH uo ae tion, gas heating.......... é pe ea. an, i 7371 do., but 220 volt d.c........... 1/20H. P. “ 5 UjZs . rer E t 7372 do., but 110 volt d.c..........1/10H.P. : 33.75 Kuksf 7471 ‘Ring supports, only, for No. 7470. a : Ze Cie 7373 do., but 220 volt d.c¢.......... 1/10H.P 30.50 Kullt ey aot! ree ecany 7374 do., but 110 volt d.c.......... 14ZH.P 35.25 Kumck | 7474 Kjelda gesting rack, Folin C a cay 7375, do., but 220 volt d.c.......... a es ne Be gas heating............... ‘eo Frnce * 00 Tels oe ee . YELP.“ a unpi e 5 $ ar oe nt 20 ee c 4 d He a i 46.50 Kuaty 7475 Individual rack supports................-. 35 Kymyj 7380 Countershatft INO ey cones sane eine ane e 2.50 Kuosb 7480 Kjeldahl distilling apparatus, with individual ‘. ee 7381 ING: 2 har rect aeons ee 3.50 Kupmn condensers, gas heating. se As Cth pa No. s 7.00 Kugbi condensers A 388 ie Pie cu Ne } Aira i 10.50 Kuref 7484 ~—“ Digestion apparatus, Sy fumeless.......... : 22.00 Kyofu 7386. 6 ot “ Precision........ 00... “32.00 Kurzo | 7485 Connecting tube, only, for No. 7484........ a a 7387 + = Extra gear, for No. 7386......... 200 tol “ 5.00 Kusnh 7486 Manifold, only, for No. 7484.............- en mp 7390 M It, 60 cycl 7487 Support stand and burners for No. 7484. ... yqcy otor generator set, for 110 vo ae e, 1 and ¢ ae single phase, a. ¢.. “265.00 Kutry 7490 Kjeldahl distilling apparatus for single deter- 150 Kyrds 7400 Mould, ouring; three 2 in. n. cavities . 4 1.10 Kuujo . minations.................++ 3 7402 pone nine 134 in. cavities. a 1.25 Kuuzh | 7500 Connecting bulbs....... a oe i = oat s x “ Pyrex.. 52mm “ 1.20 Kysji 7410 NEEDLE, INOCULATING, gles, with | 50 7501 ee 134 in. platinum wire | ee ‘ o oe 7502 ‘i ii i “with Seunved ip ; 7411 do., but with 3% i 4 in. platinum a No. 24 . # uwdy sp teesiib tiie, cs. Coat 55 Kytny 7412 do., but with 314 in. Chromel wire No. 26. aU BOWE Picci ae ee ele ie 100 Kyucu ; ; ; “ 40 K 7503 do., but of Pyrex glass. . ee ee aa ee AO KOOM | oy Ricldabl connecting bulb, Jennings: 1... (° 98 Kawpd gabe balopticons. 8680 REFRACTOMETER, INTERFERENCE, 3 ge Rayleigh- Hilger; for gases. Without Top 30x12 in. 15.00 Niefi lamp 620.25 Noply SL. do bas feld tig tor Model cual aecldin, “ 2400 Niey | 8681 Gas tubes, only... ooo, 100em“ — 40.50 Noghf sols Gee DUCODS ass tarbce eaters P : 5 nae 8682 Accessories to gas refractometer for investi- 8562 Projection screens, opaque cloth.. 6x6 ft. 8.75 Nifib gation of liquids................... set 135.00 Nogry 8x8 ft. a ee 8684 Refractometer, Interference, Rayleigh-Hilger; 10x10 ft. 55.00 aoe for liquids. Without lamp........... ea. 620.00 Normu 12x12 ft. 7 ‘yu 8685 Liquid cell, only, for above....... lem “ 104.50 Nosen 8570 PYROMETER, Hoskins thermo-electric, : 8686 Illuminating lamp, Pointolite, with resistance Type PA, single scale, 1100°C....... 67.50 Nigub for 110 volt d. G.........0.ec0.ec eee “ 139.25 Noste 8571 Meter, only, as supplied with No. 8570... 60.00 Nihlt | 3687 Lamp bulb, only, for Pointolite lamp... “8.50 Notjy 8572 Thermo-couple, base metal....... 18 in. 3.50 Nihzq 8688 Illuminating lamp, electric, with ordinary 8573 Couple handle...................0ee ce eee 1.00 Niigh metal filament lamp....... 110 vol 8.75 Noudj 8574 Flexible lead, B&S No. 16 wire. 20 ft. 3.00 Nijhz 8690 Respirator, Cover automatic.............. - 1.50 Nouys 8580 Pyrometer, Brown thermo-electric, type P, on 8691 Sponges, for respirators..............0.005 doz. 1.80 Novmg double scale.............. 1600°C. 253.00 Nijwu | gg92. Silk discs, only, for No. 8690.............. ce 1.00 Nowhz 8581 Meter, Brown type P pyrometer........... 105.00 Nekoj 8694 Respirator, Hayward automatic........... ea. 3.35 Nowyq 8582 Thermo-couple, Brown, platinum-Rhodium, . 8695 Wire gauze, only, for No. 8694............ i 30 Noard Type K pore. ees, oe 148.00 Niled 8696 Rubber pneumatic cushion, for No. 8694.... “ 1.00 Noykr 8583 = do., ah double bore fireclay insulating “ 80 Noyyo tube, without pore. tubes, terminal 8700 RETORTS, of copper........... pe . a voy head or handle.............0eeeee 112.00 Nilty 1000 ml “ 3.75 Noofa 8584 Type K porcelain tube, for temperatures up me 2000 ml “ 5.10 Nogjs to 1600' °C iibcte a Suevede suid fe eceeatie ce 36 in. 24.00 Nimiu “ in lin al, © 8.00 Nuae 8702 Copper, tinlined.... 148 p. 8585 Type J porcelain tube, for temperatures up 7 1 gal. “ 11.20 Nuahj to 1260°C. 0.22... eee ee 36 in. 12.00 Ninef Qeil. “ 15.20 Nuame 8590 Pyrometer, optical, Leeds & Northrup...... 175.00 Ninzo 3 gal.“ 20.00 Nuasm A Segal.“ 22.40 Nuawe g892 FREcTIFIER, Tungar...............6+- 130.00 Nionk | gooy ie (Fe eae, Ate) “Sl eae 8593 Bulb, only, for No. 8592........-....+0555 8.00 Nipir 1 pt. “ 3.85 Nubot 8596 Reduetor, Blair, tube only, with stopcock... 2.00 Nipai lqt.“ + 425 Nubuh 8597 do., but complete with clamp, support, : . ¥ gal. “ 5.15 Nucav flasks, stopcocks and tubing......... 6.00 Nignf | 706 “Pyrex glass, tubulated 125 vm 1.60 Nueug 8598 Reduction tubes, Pyrex glass..... 1 bulb 50 Nirip é 250 ml “ 2.00 Nudau 2bulb “ 65 Niry 500 ml “ 3.00 Nudem 3bulb “ = 90 Niroc | g797 “Glass, plain......... 150ml“ 25 Nudt 250 ml “ 30 Nueid REFRACTOMETERS is » & Ni * 500 ml “ A5 Nuewa 8600 Vol. I, “Essential Oils” Lid Posie oe eas oe Neat 1000 ml “ 65 Nu ifmu 8601 af ri “Oils, Fats and Waxes”........-- 6. a e708 i a4 taal 150 ml 50 Nugfh 8602 “ TH, “Sug ar Tables” (In preparation). . Nith =| 8708 tabulated... 250 ml “ 65 Nugib 8610 REFRACTOMETER, ABBE, Bausch & : 20.00 Niub 500 ml “ ‘85 Nugng DOMD ioe scene sodas 259 ah 320. 5 Nin a 1000 ml “ 1.10 Nugte 8611 Thermometer, for above......... 0t0 75°C. * 2.7 nae 2000 ml “ 135 Nuguy 8614 Refractometer, Abbe, Spencer.........---- 200.00 Neo A R T H U R H. T H Oo M Av==5, Cc Oo M P A N ¥ Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 8709 —Retorts, glass, with tubulation and ground in 8782 Rubber bulb. double valve, hardrubber.... ea. $0.75 Nyizi Stoppers vowloria secede 150 mlea. $0.70 Nuhjy 8784 do., double bulb, for constant pressure... “ 2.00 Nyjod 250 ml “ 95 Nuhnp | 8786 do., double valve, black rubber........-. a 15 Nykne 500 ml] “ 1.10 Nuhrh 8788 Rubber caps, diam.............. 1 in. “ 1.25 Nylew 1000 ml “ 1.35 Nuhkvz 5% in. ‘ 1.40 Nylhg 2000 ml “ 1.65 Nuhzr 34 in. “ eo ae % in. “ 40 8712 RHEOSTATS, Sliding contact tube, T. R. a z “ 1.40 Ne Laboratory type.......... 3200 ohms “ 8.00 Nuiom 14 in. “ 1.40 Nylon 8713 Lo eke rrecen epee dae Serva ee 1750 ohms ‘ 8.00 Nujck 14 in. “ 1.40 Nylef 8714 Ona tees es hog ge toned 920 ohms “‘ 8.00 Nujyr 134 in. “ 1.50 Nymft 8715 Oe serene tats 630 ohms “‘ 8.00 Nukre Qin. “ 1.65 Nymin 8716 do....... 370 ohms “ 8.00 Nulhy 3 in. “ 1.90 Nymmf 8717 DOF anes sana kien cerca foes 210 ohms “ 8.00 Nultz 8790 Rubber finger cots, heavy........ Small ‘“ 15 Nyney 8718 do. ti 120 ohms “‘ 8.00 Numlp Medium “ 15 Nynim 8719 desea, 70ohms “ 8.00 Nunbi Large “ 15 Nynme 8720 DOF 5 Ace Meek tac SE ea 50 ohms “ 8.00 Nunzp Thumb “ .75 Nynrt 8721 do. 25 ohms “ 8.00 Nuokp | 8791 do., of thinnest rubber......... Small “ 30 Nyogp 8722 OZ ites c 14ohms “ 8.00 Nuozk Medium “‘ 40 Nyokh 8723 DOs ane sh ten necks S8ohms “ 8.00 Nuprz Large “ A0 Nyona 8724 do.... 4ohms is 8.00 Nugoe Thumb “ A0 Nyors 8725 do. 2.8 ohms 8.00 Nurey 8792 Rubber gloves, chocolate color, size No. 7 pr 1.10 Nypgo 8726 Os vahnouricn cece ves nade stn ade 2ohms “ 8.00 Nursv 8“ 1.10 Nypjt 8727 dO cisssise lohm “ 8.00 Nusij 9g“ 1.10 Nypnz 8728 OO is elas win ake ee 0.6ohm “ 8.00 Nutae 10 “ 1.50 Nyptn 8740 Coil, 10,000 ohms, 1/5% ................. . 4.00 Nutst 8793 do., thinnest pure gum tissue... No. 644 “ . 85 Nyqqs 8741 do., mounted in Bakelite tube........... “22.50 Nuuin TS 85 Nygtm 8750 RINGS, Concentric copper, with cover. A = ie 2 in set set AO Nuvac Bis “ 35 Novae 3 in set “ 56 Nuveu Ohi di “din set “ 72 Nuoki 9 85 Nyrhk Bee “yc sunk | 8794 —do., heavy white, “acid gloves”. No. 9“ = 3.75 Nyruj in set i 96 Nuvoz 10 “ 3.15 Nyryb oe set rr 1.60 Nuun | g795 do., black rubber, cotton lined.. No. 9 “ 3.00 Nysps in set 2.40 Nuvzd 10 “ 3.00 Nysui 8 in set “ 4.00 Nuwex 1d “ 3.00 Nese 8751 " a Porcelain, with cover. 12 3.00 Neat a a A oe oe 8796 Rubber policeman, narrow, with glass rod. . doz. 80 Nyt 5 in set “ L75 Nuwe 8797 do., rubber part only EN Nene 50 Nywmz 7 in set “ 2.10 Nese 8798 Rubber policeman, wing shape, with glass rod “ s 1.05 Nyvaw 9 in at 315 Nuzgo 8799 do., rubber part only................08. 15 Nyvsj 8752 “ “ Japanned iron, with ; 8800 Rubber policeman, new shape, with glass rod * ef 95 Nywns clamp; 4ringsinset....... Bauae set 1.60 Nuzyd 8801 do., rubber part only............-...++. 65 Nysfi 8758 ES Fi Panic de cies Su 3 in. ea. 25 Nuyld 8802 Rubber policeman, hard rubber handle... .. - 30 Nyydt 4Y4 in. “ 45 Nuyow | 8803 do., rubber tip only. ................055 10 Nyysg Le - “e ae # Nay 8810 RUBBER STOPPERS, A.H.T.Co. Special, 814 in, “ 1.20 Nuyye SO) let wheel oeende we ioeles No. 00 lb. 1.50 Nyzhe 93gin.““ 1.45 Nuzeu 0 1.50 Nyzlu 8760 Ring, support, with short clamp..i. d. 21 in. “ 12 Nuzsn I 1.50 Nyzon 31¢ in. “ 18 Nuzyb 253 1.50 Nyzub 8761 do., with long clamp......... i, d. 234 in. “‘ 16 Nyapk 3 1.50 Oaabi 314 in. “ 18 Nyase 4“ 1.50 Oaafb eS in, * ah a 5“ 1.50 Oaaiv 34 in. . ybao “ 8762 do, with opening............ id. 214 in.“ 20 Nybsd oe Seas Beat He i ge i ; _ . 8lg in. 25 Nybyr g « 1.50 Oaaty 8764 do., with extension bar....... id. 21¢ in. “ 14 Nycre g « 150 Oar 324 in. “AS Nycuy 10“ 1.50 Oabbs yin.“ «18 Nycyg 11“ 1.50 Oabfa 554 in. “ 30 Nydei 19 « 150 Oabi 8770 Roasting Dishes, Denver Fire Clay, 3 in. doz. 1.80 Nydlg ac Sey Guie pin Fee eam? | 8811 do., but with one hole......... No. 00° 1.50 Oagjr in. 2.60 Nydnl 0 150 Oacni 6in. “ 3.90 Nydoj 1“ 150 Oacra 8772 RUBBER BULB, red rubber .... 2 ml ea. 14 Nydux Qa 1.50 Oacym 8773 do., black rubber............- 1ml “ 20 Nyeiv 3% 1.50 Oadde 2 ml “ 25 Nyelp 4“ 1.50 Oadhu 8774 do., red rubber, stout wall... .. loz. “ 13 Nyfak Me 1.50 Oadko 44 02. “ 15 Nyfec 6 “ 1.50 Oadnh 1 oz. “ 16 Nyfiu la 1.50 Oadut 8776 do., white rubber......... length 314 in. “ 21 Nygeb St 1.50 Oadyl 33% in. “ 22 Nygit 9 “ 1.50 Oaebf 4in. “ 25° Nygml 10 “ 1.50 Oaeez 8777 do., single valve, 2 in. diam... .274 in. long “ .28 Nyhea lL 1.50 Oaeir 8778 do., double valve, with 5 inch tube....... “ 40 Nyhor 12 “ 1.50 Oaemj 8780 do., black rubber, with long tube........ i 15 Nyikn 13 “ 1.50 Oaega 60 A R T H ‘ O M P A N Y Cat. = Description c 8812 Rubber stoppers, same as No. at Gay wae || a with two h ‘ Descripti Paras 0 ” "i 50 Oafgu oe ee tubing, nance ion 1 Oe eee Word se eaee yr 2 : 1.50 ae bore % i in, “ 12 Oa ab 3 1.50 Oagaf dyin.“ 25 Oayee 4“ 1550 Oaghr | ein“ “31 Oagas ; “150 Oaghl | 8846 Rubb 3% in, “58 Oazei aH 130 one er tubing, for Gooch crucibles ae 75 Oaziwo 8“ 1.50 oe . ; bore 34 in. * 18 Obabh ce Tao bein“ 23 Obage : 50 Oahb in.“ 24 Obj i 1.50 Oukne pe Rubber tubing, Haemacyto 134 in, “ 28 Oho Sik bake iz “ 1.50 Oakhg 850 Rubber tubing ae meter. ......... te “10 Obben ppers, new extra long shape, ait 1.50 Oahlt = S a ea. 1.00 Obbis No. 20 “ : AMPLERS, Ji ah 2 io neg y JONES. .... 2.00 size 7 in. “ 17.00 Obcez 2 150 Oaiin x6 in. “ 23.25 Ob 150 Oath ee S10 in. “30.00 Obes 24 1.50 Oaipy $4 SAND BATHS, doep form, iron, diam, 3 in, 4.35 Obdmi ne So ; 25“ 1.50 Oaivm pstomm, ron. died te 10 Ob o., but with one hole. ..... N a 1.50 Oaize 4in. “10 Oban ... No.20“ 1.50 Oajoz 5 in. ‘18 Obemk 21“ 1.50 Oajun 6in. “ "22 Obe a 6 aon oat ea "35 Obes he akil in. “ 40 2" 150 Oaknd 8865 do, but shallow form _ 10in« 8 tee siG a | --90 (nn diam. 3in. “ "10 Obj o., but with two holes... Ren Tee ae . ae Obgin 3 E : 50 Oalji in. “ J 21 150 Oana in" 18 Obhec aa A Oe i ee i . a. al: : 30 0 a4“ 150 Die Pe Sand bath, with gas burner 10 in. “ 60 Obl 9820 Rubber 25“ 1.50 Oamgn de, WiROU EMO ON - {19.20 Obig B20 Rubber stopper for sulphur deb. N oe 6x8in. ““ 2.00 Obirk 8822 i ‘or Brown-Duvel moisture jie 0. 6 - 3.20 Oamyc 887 . 8x10 in. “ 2.80 Obiye o., for Kjeldahl flasks 500 ml.. Solid oo 3.0 Oana 0 Sand glasses, in wooden frame Oe in“. 345 Objes . “ ee 20 0 ae 4 ae : 2 Rubber tissue, or dental dam 1 hole . 1.20 Ooi me min, et Ohtey a dese Sw ona ae. Sq. ft. 55 min. “ pe SBE RN ee a amin 25 Oday nd made, cloth-wrapped . bore} i : 3 min. “ 25 Oblle . * in. ft. 07 Oapsl em 35 Obl in, i 09 Oagav 10 min. “ 5 Obmue aa 5 Out | sz Sop ae “1.50 Obmlb sin Oomk ps, horn, shallow, with handle 100mm “* Seon Ae 25 Oaque 120 mm “ 30 aoe .s «30 Oarbs 140mm “ = .35 Obofl 8831 4 in. Se pee. |e « Serta ene ea 160 mm “ 40 Oboj do., but thin wall... ee eae | , without handle, 60mm “20 es eo 4 Rapti ore lg in. 7 05 Oasdn 80 mm “ “05 ae ee )6|6 ae |e S00 nn ee Obpnt . - . a“ te in. “ ” pee ops, weighing, glass, shallow. . . 246 in. “ =o pie in. “ 18 Oassi vil do. deep form ¥ 8% i in, “ : rel 8834 Rubber tubing, F. S. pure gum, thick ae 17 Oaszu | 87 2 etn AE boas 5 Bee, 33 Oe , a 8 Scorifiers, Denver fire clay, di a4: 50 0b bore i in. “ 08 Oatpn @ clay, diam. . 2in. 100 3.65 Obe yn a Gal 234 in. "3.80 Obuiz i in. 12 Oauen 8880 : : 24 in. “ 4.35 Obuno ee oa | ee ie es ae z in.“ 25 Oauke | gape do., set of four sized,.....-.000cssocc- ea. 50 Obviy % ig “ 2 Gores do., optician’s, 3 inches long............. = a Olbnoya in. OMIT: | ca, Genie APRERTTAR, ‘berated ea. i f 8835 i a 7 a ay ae EG ee eee International is lo., but thin 4, in. .60 Oavbo e -bottle head, f " , walls ops see bore yin. “05 Oavws a im but for 220 volt d. ¢.. se at dic, “ 165.00 Obynk sarees ee 06 Oawap | 8893 do, but for 110 vl, 0 yee 8 6... é Wen Gok ubber tu D. 09 Oawdj " volt, 60 eae 00 Ueda bing, A. C. pure gum, thick wall wij | 6884 Four battle head, only, MBI ric Nae One bore 3 mm ‘ 08 Oawse Shaking apparatus, International, ‘with Rick- i 4mm ‘ 08 Oawvy Po ards 24 bottle head, for 110 v “ 5 “ 96 do., but fe olt d. ¢.. 165.00 7 mm "12 Oaweq | 8897 dab ‘or 220 voltd.G......-4..- “4 i Oe ae 18 Oarek | 8898 do but for 10 vol, 0 eye a 6... AOA Oats ” but for 220 volt leaks ‘ colt, 60 cycle, a. ¢........ “167.00 Oi 8 mm ft. « = 25 O € | 8899 Rickards 24 sputum bo tle head, onl eee 60. 00 0. ab A R T H U R H. T H O M AS Cc O M P A N AY: Cat. Code Cat. Code No. Description Size Unit Price Word No. Description Size Unit Price Word 8906 Shaking apparatus, C.S.&E., for 110 volt, 60 8952 Sieves, Tyler standard, 8 inchs diameter CY CENA? Chern cate atm an uae Sis ea. $130.00 Ochdu 180 mesh ea. $8.40 Odnek 8907 do., for 110 volt d.c......... Fier E ls “130.00 Ochyd 190 mesh “‘ 8.80 Odnop 8908 Test tube holder, only, for above.......... “ 15.00 Ocild 200 mesh “ 9.15 Odnyo 8909 Flask holder, only, for above.............. “10.00 Ocixe 220 mesh “ 9.85 Ododl 8912 Shaking apparatus, steel laboratory model... “ 30.00 Ockep 240 mesh “ 11.40 Odogf 8913 do., sugar laboratory model............. “45.00 Ocleo 300 mesh “ —-15.00 Odokx 8916 Shaking apparatus, box form, without motor “ 36.00 Ocmsk 8953 Cover and receiver, for above............. set 3.00 Odozs 8917 do., with motor for 110 volt d.c......... “ 60.00 Ococp 8954 Sieve, Tyler standard cement, No. 100...... ea. 10.00 Odgua 8918 “« «© 110 volt a.¢., 60 cycle. “ 60.00 Ocoog 8956 “Cement, brass, 8 inches diameter..... “ 9.60 Odsix 8920 Shaking apparatus, small, with 110 volt uni- 8960 Sieve, brass, brass frame, 5 inches diameter, Ver'sal MOO: <2 vas sag semen eines nS 75.00 Ocpic diameter of perforations... 14mm “ 2.20 Odthy 8930 Shears, long, nickeled, length... .. 6 inches “ 1.35 Ocria 1mm “ 2.10 Odtux 8 inches “ 1.70 Ocryt 2mm “ 1.95 Odual 10 inches “ 2.20 Ocsiz 3mm “ 1.85 Odudf ; 12 inches “ 3.15 Ocsno 5mm “ 1.75 Odugz 8931 “Short, heavy, length...... 814 inches “ 1.50 Octha 8961 — Sieves, brass, set of five, with cover and re- 8932 “ Tinners, length.......... 914 inches “ 2.15 Ocuhz COVER esr crag oeteee cutawannseeu eee set 11.85 Oduvw 1114 inches “ 2.60 Oculr 8962 Cover and receiver, brass, 5 in. diameter.... “ 2.00 Odvyn 1214 inches “ 2.85 Ocuok 8972 Sieve shaker, Per Se, hand driving, with pul- 8940 SIEVES, brass gauze, wooden frame, 6 inches ley for power...........-..0.0e sees ea. 175.00 Odrut diameter................. 10 mesh “ 60 Ocord 8974 st “Hand driving, for sieves, diam- : 20 mesh “ -70 Ocwal Cleric wauai tuesa are eee 5inches “ 41.60 Odyoe 40 mesh “ 80 Ocwlp Ginches “ 41.60 Odyry 60 mesh “ 1.00 Ocwyo 8 inches “ 41.60 Odyog 80 mesh “ 1,50 Ocade 8980 Silica rod, transparent, 12-inch lengths, diam- 100 mesh “ 2.00 Ocxgy CbORE Sas, Sie yeaa chavs 1mm “ -50 Odzlk 8941 do., 8 inches diameter......... 10 mesh “‘ -90 Ocyeb 3mm “ 1.25 Odzur 20 mesh “ 90 Ocytt 8981 Silica tubing, transparent, 12-inch length, 40 mesh “‘ 1.00 Ocyln outside diameter........ 3 to 5.5 mm “ 1.00 Ocanc 60 mesh “ 1.20 Ocyog 7mm “ 1.90 Ocatg 80 mesh “ 1.70 Ocysy do., 24-inch length, 0. d......3 to 5.5 mm “ 2.00 Oebki 100 mesh “‘ 2.50 Ocyzk 7mm “ 3.80 Oebri 8942 do., 12 inches diameter........ 10 mesh “ 1.15 Odabd 8982 Silica capillary tubing, bore...... 1 mm ft. 3.00 Ocecna 20 mesh “‘ 1.35 Odaex 8986 Slide rule, Mannheim type................ ea. 10.00 Oedhm 40 mesh ‘“ 1.60 Odaip 8987 ABE DUNO: ards aed tes anh ds ee “10.00 Ocefp 60 mesh ““ 2.00 Odalj Soap, Green, see REAGENTS. 80 mesh “ 2.60 Odaoe 8990 Sodium spoon, with ramrod............... y 45 Ocetm 100 mesh “ 3.75 Odasu 8992 SPATULA, glass, flat blade 5g inch wide... “ 25 Oecfov 8944 Sieves, nested, brass gauze, tin frame, set of 8994 et Horn, double, length.. 100mm “ 20 Ocgya CLG ee cere eines chy One arene set 50.00 Oddli 120 mm “ 25 Ochbu 8946 Sieves, brass gauze, brass frame, 5 inches 150 mm “ 28 Oehhi Mame beh fe Se cel ko niee 10 mesh ea. 1.70 Odeyg 200 mm “ 50 Ocehla 20 mesh “ 1.70 Oddey 8996 Spatulas, porcelain, double, length 120mm “ 43 Oeilz 40 mesh “‘ 1.80 Oddim 150 mm* “ 50 Ocipg 60 mesh “ 2.10 Oddlg 195 mm “ 66 Ocisk 80 mesh ‘“ 2.20 Oddrt 8997 n Knob one end 200 mm “ -74 Oejor 100 mesh “ 2.25 Oddol 310 mm “ 1.32 Ocekat 200 mesh “‘ 4.70 Odeab 442 mm “ 3.18 Ockid - 8947 do., 8 inches diameter......... 10 mesh “ 2.85 Odena 8998 “Steel, flexible, blade... . 3 in. “ -50 Oelas 20 mesh “ 2.90 Oders 4in. “ 55 Oelek 40 mesh ‘“‘ 3.15 Odeum Sin. “ 60 Oelic 60 mesh ““ 3.35 Odexg 6in. “ -70 Oelmu 80 mesh “ 3.40 Odfby 7 in. “ 15 Ocelpn 100 mesh ‘“ 3.40 Odfgo Sin. “ 1.00 Oclud 200 mesh “‘ 8.00 Odfjz 10 in. “ 1.75 Oelzt 8948 Cover and receiver for above, diam. 5 in. set 1.50 Odgny 12 in. “ 3.00 Oemfh Sin. “ 1.85 Odgrg 9000 “Stainless steel, blade.... 3 in. “ 90 Oemyu 8950 —_Sieves, brass, nest of five, with cover and re- 4in. “ 1.00 Oendo ceiver, diameter.......... 5 inches “ 11.55 Odhov 5in. “ 1.10 Ocenia 8 inches “‘ 18.45 Odhuj 6in. “ 1.30 Oenon 8952 Sieves, Tyler standard, 8 inches diameter 9001 “Steel, nickel-plated handle 3in. “ -15 Oeolt 20 meshea. 3.60 Odimz 4in. “ 80 Ocozg 30 mesh “ 3.60 Odiro § in. “* 90 Oepuz 35 mesh “ 3.60 Oding 6 in. “ 1.00 Ocgef 40 mesh ‘“ 3.60 Odiya 8 in. “ 1.30 Oegok 45 mesh “ 3.90 Odjbu 9002 . “Wood handle, blade 3in. “ 50 Oerfe 50 mesh “ 3.90 Odjig 4in. “ 10 Ocriw 60 mesh “- 3.90 Odjmy 5 in. “ -15 Oermo 70 mesh ‘ 4.10 Odjrn 6 in. “ 95 Oerph 80 mesh “ 445 Odkav 9003 “ “Pill Knife,” blade... . . 3% in. “ -10 Ocskr 90 mesh “ 4.80 Odklz 9004 “Folding, blade......... 3 in. “ 1.20 Ocetak 100 mesh “ 5.20 Odkrm 9006 “Hard rubber, blade... .. 4in. “ 40 Oetzl 110 mesh “ 5.35 Odlaw 6in. “ -50 Ocufz 120 mesh “ 5.50 Odika Sin. “ 15 Ocujr 130 mesh “ 5.95 Odlor 9010 SPECIFIC GRAVITY BOTTLES, Gay- 140 mesh “ 6.25 Odluf Lussac, unadjusted, capacity 1 ml “ -30 Oevce 150 mesh “ 6.60 Odmat 2 ml “ 30 Ocvhu 160 mesh “ 7.00 Odmid 5 ml “ 30 Ocolm 170 mesh “ 7.70 Odmrk 10 ml “ 40 Ocvut 62 T H 63 A R T H U_R H. O M A 5 C OQ M P A N Y Cat. ‘ Code Cat, Code No. ; Description Size Unit Price Word No. Description Size Unit Price Word 9010 Specific Gravity Bottles, Gay-Lussac, 9084 Nutting Photometer, Hilger............., ea. $643.00 Oguom unadjusted, capacity.......... 4 af ea. 6 ao ae eajusiebls stand, for tubes of liquid........ “ 20 Ogvup . ml ‘ -55 Ocwoe be, 100 mm long, for above............. “17.75 Ogzim a 3 gies - 100 nl : $5 Oewzm 9090 SPEOTROPHOTOMETER, Hilger, com- Pee 0., accurately adjusted, capaci : 60, Ocex. PIS te 3 S88 a's sos xem do eratacoetecostociesen “1261.75 Ogyi 2 ml “ 60 Ocxur 9096 Spectro-photometer, hand, Nutting........ “100.00 Ogywi 5 ml “ 60 Ocyaf 9100 Spectrograph, quartz, for ultra-violet, Hilger “ 452.50 Ogenz 10 ml “ -70 Ocyex 9120 Ray filters, Wratten & Wainright, set of 8. » Set =: 13.00 Ohagl | 25 ml “ 75 Ocyip 9122 Monochromatic burner, for sodium flame... ea. 6.00 Ohawe 50 ml “ 1.10 Oeylj 91244 —C—i“‘(i‘ SS and white light burner... ... “12.00 Ohbno : . _. 100ml “ 1.20 Oeyoe 9126 Sodium flame attachment................. “| 4.00 Ohego 9012 Specific gravity bottle No. 9011 with tin case 9127 Asbestos block, only, for above............ « -30 Ohdie and tare weight, capacity. . 25 ml “ 1.50 Oczfu 9128 Electric lamp, for 110 volts............... a 13.50 Ohecp 013 Specif ty bot Ga 50 ml “ 2.00 Ocznd 9140 Spectrum tube, Plucker, empty............ 4.00 Oe ific gravity bottle, wi ermometer, 9142 sf “filled with Neon........... “12.00 Ohfei capacity... 2... 10 ml me oe One . oe ee “« * Aelium......... ie as oe 25 ml “ 3.00 Ofai 914 e “empty, with two stopcocks.. “ 2.50 Ohgte 50 ml “ 3.50 Ofamd 9150 Absorption cell, bottle form............... fe 1.00 Ohige 100 ml “ 4.00 Ofagu 9151 s “ U-shaped.........0.002... ef 1.50 Ohiap 9014 Specific gravity bottle,Boot...... 25 ml “ 3.00 Ofbes - 9152 i “ Circular, glass stopper...... ee 3.00 Ohipk . 8 > ca deat; 50 ml “ a Ofbik. 9154 ‘ “ 30x21x21 mm............. a zo ove 901 * , ()) 1 Eee are oe se 3.50 Ofemb 9155 ie “ Two-compartment........ go 1.50 Ohta: 9018 Specific gravity bottle, Regnault, for liquids, 9160 “with bottom piece extended. “ 3.00 Ohkyg adjusted, capacity......... 25 am “ ss ee ~ | 9162 “ Hilger patent precision..... e ee Oe 50 ml “ i ‘eax 9164 sf “Adjustable, of clear glass... “ ‘10. mel 9019 do., without adjustment, capacity 25 ml : A0 Ofeu - {| 9165 8 “ 4 ed quartzend plates i 30.45 Ohmty lids adjusted, capacity 25 ml“ “Bh Gfin’ | amy. nore mand far aheorptin cells......... 5.00 Ohoto 9020 “" for solids, adjusted, capaci ; -80 Offa. : or spec’ es e ‘ 50m] “ 1.00 Ofmm =| 9172, spark terminals “ 150 Ohowg 9021 “« « «unadjusted, capacity 25 au “ ae ae 9180 Sponges (average 14 to pound)............ lb. 1.50 Ohpof : 50 12 : 9022 Specific gravity bottle, Reischauer 25 ml “ 1.10 Ofiel 9182 SPOONS, horn, length.......... 100 mm ea 10 Ohqyk Pp or ue “ 50 ml “ 1.35 Ofiid 120 mm 22 Ohrbe 100 mi “ 1.60 Ofilz 150 mm “ 32 Ohrgu 9023 = do., graduated in mm on neck.. 25-ml “ 1.60 Ofjas 200 mm @ 48 Ohrkm 50 ml “ 1.85 Ofjie 240 mm - 2 oe een Reise ton, Toone, | 98 * © ctotutacnd length omm” oeOmee 9024 Specific gravity bottle, x shane Bein ia: a ye nee Spatula end, leng’ ian e 20 he 9026 “i ‘ e HCON 22 se vGisceye 8 antes . : ‘m : ‘i . ; 928 Hogarth... ooo. “ 2.30 Ofnuz 150mm “38 Ohsyi 9030 “ “ tc ground on caps...... “ 1.00 Ofokt 200 mm a 60 Ohidy 9032 mo “Walker, liquids...... “ 2.30 Ofpam 240 mm “ 1.00 Ohtio “ “ « “ is, liquids... “ 2.60 Ofqoi : 300 mm 1.75 Ohtob 9033 Vis, q q ty i “ 25 Oh 9340¢=~«C A (HE ERI oie acca “1.50 Ofseb 9184 Porcelain, spatula end... 96 mm “ @ Ohy 9035 ne Hf “« * Hubbard-Carmick... “ 1.50 Oftfy ° ies is "46 BRL: SPECTROSCOPES, See ee Ee ORO EIEES 160 mm “ 60 Ohuig Agios . +s “ ee 9190 STAINING DISH, with tray and holder.. “ 1.50 Ohoki 5040 SPECTROSCOPE, Miniature direct ISO Hue Ofues 9191 Glass dish, only, for above................ so 75 Ohwfr ae “ “ “ “wo «“ 30 oe , 9192 se tray, only, oe and cores subbing awed Sg a a ik : a% ma a 9193 Nickel wire holder, for above.............. 7 a i Direct vision, Spencer.. {25.00 Ofzew | 9194 Staining Dish, Rectangular, for ton slides.“ 45 Ohyjh aos qe “ . O ont Gone | oe Jar, Coplin, for ten slides...... . a a ; Pema Saal modal... ss... 42h Oyoas | SRE Nap, with glamcover.. “35 Op 9048 Sc 9199 cork stopper. 30 Oialz 9050 se Burker Le Adiga ae : a Coany 9200 “ ¢ Fpryardic sa ae a ‘25 Oiaxa 9052 “Wavelength, 8. & H.......... Geo eee 6.00 Titwe “© Oe: , il tural saci. Giessen were eae 1 lb. ctn 16 Tiucs Silicic, com’l, powder (Silex) na ian "50 Tiufm “ 1 6 De DOW A EIinve cic Sarna are eee Baker Analyzed 1 oz. eb 17 Tiumy as iy BOWE iat 2 4 oz. ch 45 = Tiuot 1 lb. cb 1.28 Tiurn “ “ ivi _......... Baker & Adamson 1 lb. .24 Tiuxb e. Be, precipitated -s20se+7 5 Ib. 5.90 Tivav “ an Se Pe aac Res Ar REA eee nea Merck Blue Label 2 oz. gb 45 Tiven * Silicotungstic....-------- +s 1 oz. gb 115 Tivug A Ro i We oR H. T H O M A S COM P A N_ Y Item Maker or Brand Size pkg. Price Code Word Acid, Stearic, purified by Aleohol................ Baker Analyzed 1 |b. cb 86 Tiwem 5 lb. can 3.60 Tiwgi "e cS Ui Scab a DOW dens v.x.ctacoveinun ae ae Merck White Label 1 lb. cb 52 Tiwyx *© SuCCiniG;Cs-Dos-ask ec eevee ee Bee ee en ee Baker Analyzed 1 oz. cb 38 Tixgh i CAIN Sb Dna e ad im ot th Marat eee Neneh e Merck Blue Label + 02. ch on fee 1 oz.c¢ ‘ txr “ Sulfanilic, purified....................000- Baker & Adamson 1 oz. cb 12 Tiyas 4 oz. cb .40 gee 1 lb. cb 1.38 ‘tye ss ee c. p., crystals, (Acid Sulfonic)..... Baker Analyzed 1 lb. cb 1.15 Tiymu Ss Sulfanilic:s: 42sec cers Wears ms eat Merck Blue Label 1 oz. cb 30 Tiytf CO Sulfosalicylie:::cchsccevg bese te eee Es Se Ey SASS 1 oz. cb 1.25 Tizdl 6. (Sulfuric: Com 1665.2 can hb ee See AG slancublnatauns Mae ee ees 2 lb. gb 63 Tiznq gb extra -50 : ee SS SCOMAACO9 2 ste Seinen eae eek I f ten 9-Ib. glass st d bottles, at 6 IDSs cue. . (Gloss actlas ah og yeueh, cxtcay eae, ab GHigD cotre: ee 90 Ib. case 12.40 Tizte Acid, Sulfuric, c. p., sp. gr., 1.84................ Baker Analyzed ( ee ap pa epee g : ‘mace gb extra 50 Base ee ea ee ea ceca 90 1b. case 15.10 Tmafy Carboy 180 Ibs. approx. at 8c per Ib.......... 00 cece cece eee tenet e tener eres ee es artey eee Tmais carboy extra 6. Acid; Sulfuric; Copia en eee Ss ah a eae eee Baker & Adamson 2 lb. gb 1.08 Tmaof gb extra .35 See eee hoe 90 Ib. case 14.50 Tmaut Acid, Sulfuric, c. p., Nitrogen free............... Baker & Adamson ie lb. gb 1.26 Tmebc gb extra 35 f ten 9-lb. gl d bottles, at 18 Ibis Wales Duccion ot Ste cud Soe ease, bea exten. ee ene eee ar ry 90 lb. case 17.20 Tmedy Acid, Sulfuric, c. p., (Low in Nitrogen).......... Baker Special ; He Ep ae Tonalin .gZ ‘i ‘memg -Ib. gl d bottles, at 18 Ib... Gise Poider et bbe exch, eee aes, ay S00 ee deere mem eRe 90 Ib. case 18.70 — Tmeob Carboy, 180 lbs. approx., at 12c per Ib..............2 000008 eee cane en Tmegx : carboy extra : Acid, Sulfuric, c. p., Arsenic free................ Baker Special 1 lb. gb -42 Tmeuwl eee gb 1.35 Tmeyh gb extra -50 “ BES SPDs LBA woes avers as aoe eae wears Merck Blue Label 1 lb. gb -80 Tmigo 9 lb. gb 4.00 Tmiik a SS QO uses Ware ea waa eee eee asus aeshens Merck Blue Label 1 lb. gb -60 Tmipv 9 lb. gb 3.00 Tmisp ee 20%, com'l. fuming. pecans sas Baker Analyzed 1 lb. gb 45 Tmizb ne gb 1.62 Tmocq gb extra 50 -lb. d bottles, Iba Le tie ca ee ee Cece deisueceae a ante tae 90 Ib. case 21.40 Tmoen Acid, Sulfuric, c. p., fuming 15 to 20% SO3...... Baker Analyzed Re eR Gee Tmoly { .Z 24 Tmoor gb extra 50 i “ —e. p., fuming, 15% SO3........... Baker Adamson 1 lb. gb 74 Tmovd 9 lb. gb 3.42 Tmoxz es “fuming. For Nitrogen determination Merck Blue Label 1lb. gb 1.00 Tmueg ss “ —e. p., fuming 22 to 30% SOz....... Baker Analyzed d, if gb -73 Tmuls { 9b. gb 3.96 Tmuol gb extra 50 & “fuming, about 15% free SO3....... Merck Blue Label 1 lb. gb 1.00 Tmuxt “* Sulfurous, ¢. p., solution (Sulfur Dioxide Solu- ELON) tacos ba es charts Aiea Sees Baker Analyzed 4 1h eb 26 Tmyec 1lb. g 43 Tmygy 5 lb. gb 1.30 Tmylo es ef CLD Oo Ooi twat ocala Baker & Adamson 1 lb. gb 35 Tmyrt 5 lb. gb 145 Tmyyn ae fe about 6% SO¢ «2.224 wh eee ee cavers Merck Blue Label 1 lb. gb 85 Toagr “ Tannic, U. S. P., powder (Tannin) Merck White Label 1 oz. ctn 17 Toamf 4 oz. ctn 39 Toapy 1 Ib. ctn 1.35 Toatq ee oS SCE Deseo ets ome laoees ithe dlagh Baker & Adamson 1 oz. cb 19 Tobac 4 me ch .65 Tobcy 1lb.ec 2.38 Tobho A R T H U R H. T H O M ‘A .S C O M P :‘A N_ Y Item Maker or Brand Size pkg. Price Code Word Acid, Tannic ......... hae Ee AO oa anaes Merck Blue Label 1 oz. eb .35 Tobnb 8 oz. cb - 1.35 Tobrt “ Tartaric, U.S. P., crystals... cee 4 oz. ctr 19 Tocab : 1 lb. etn. -62 Tocet ss US: Py POW iene wareuneead Merck White Label 4 oz. etn 19 Tocmd , 1 lb. etn .63 Tocoy SS 26. De ACRY StS). a oAcoccapassoiaateahaneiu aces Baker Analyzed 1 oz. cb 17) = Tocwi - 4 oz. cb 45 Todby 1 lb. eb 1.26 Todes 5 lb. eb 5.65 Todhm 25 lb keg 25.00 Todji @:. Py GFYStalS 2. enscee cae wean Baker & Adamson 4 oz.‘cb A3 Todtn 1 Ib. cb 1.52 Todyd - : 5 lb. eb 7.30. Toeaz oe BRD a sibse is geld pons. alteradlaeh ted peed aendabien Ra Merck Blue Label 4 oz. eb -50. Toehl 1 lb. cb 1.50 Toeij 5 Ib. cb 7.00 Toekf - be ON WEEE ce cosas Rees AGES Uae sa Nig ee oer 1 gram 65 Toemb 10 grams 5.25 Toeow “ Thymic, see THYMOL CRYSTAIS........0 602 “ Titanic, c. p., anhydrous see TITANIUM OXIDE ANA YD). ooo cease tee OMe ee eee ete eee Teese. ages ‘© ¥richloracetic, U. S. P., erystals............ Merck White Label 1 oz. gb 42 Toeuk 4 oz. gb 1.40 Toewg 1 lb. gb 4.62 Toeyc ‘ Tungstic, technical powder................ Baker Analyzed 1 oz. eb 38 +. Tofgm ‘s ne Ci Paid hoa ten aGe eRe elias Swhidae skate imanedte me 1 oz. cb -90 Tofov ‘ 1b. cb 9.00 Tofsn 8 TUPIC $C. Dian ison eee te ate Meuet en Sees Pfanstiehl 1 oz. eb 3.50 Togdr «Solution, see SOLUTION ACID URIC .......--.---eeeee5 veer ees Pena ‘“ Valerianic, trinydrated (Valeric)............ Merck White Label 1 oz. gb 50. Togmz . ‘ 1 lb. gb 5.25 Togro OTT A VANE aco. sc chap dee dee RE ERY SRE EY Tce eS eeeatenectni ace 5gramgv 2.25 Togzy 10 gram gv 4.50 Tohbu 25 gram gv 10.00 Tohdq fim ee ace Sade eL Baltics Nena HO Pfanstiehl 10 gram gb 5.00 Tohje pee 25 gram gb 12.00 Tohmy ! in shreds, pri MICE.) nach acca Ree RE A. H. T. Co. No. 40 8 oz, pkg 75 Tohtj Agar Agar, in shreds, prime whi ; ee de ae of ‘25x1 lb. ctn 31.50 Tohxb 50x1 lb. ctn 61.00 Toiav 100x1 Ib. ctn 120.00 Toicr i HO Shred sy old fan tee oo dp eevsaltinbn dents : Merck Blue Label 1 oz. cb 25 =©Toima ee 1lb.ch 75 © Toios se £6 PO WOEE Ss orl si cise bong ey Ba oneness Merck Blue Label 1 oz. cb 25 Toive ROMA EE Neots 1 Ib. cb 1.75 Toixa et “ “Bacto,” granular..........--.-+-+-+ Difco a3 1 Ib. ctn 2.00 Tojie . . “ chopped shreds......-..--------+05> Difco 1 Ib. ctn 1.20 = Tojrl a st i CO cp enhupe mnie Difco ; 4 oz. cb 1.80 Tokhf Mayattment delyarete 1lb.ch 6.25“ Tokkz ee a ient ¢ Dice Sicssaioeier Difco 4 oz. cb 1.55 Tokrk 11%, nutrient dehydrate ; ae Pee noe “ as i ,K iede.. Difco 4 oz. cb 1.40 Tolco Triple Sugar, dehydrated, Krumwie ree 1 Helce “ “ BSG tien anions vaces i7,... Difco 4 oz. eb 1.50 Tolmu dehydrated, Endo’s.... ite Bee Tolon i RVs, cas eae as hetatmes cater theay Mera cadantes ee ,.. Pfanstiehl 1 gram cb 50 Tolvb Alanine (Racemic).......----- een 200 Tout 100 gram cb 18.00 Tomen Alant Starch, see INULIN......-..-+--+-: nwwe! Ae Pee Dede, paievdiaes” “asa : Bo osid davis diana vac RRM ATS Difco 4 oz..cb 90 §=Tomlv Albumen, from blood......-------+-> se 1lb.ch . 2.70 Tomng “from eggs, impalpable powder, soluble. . Merck White Label i om ep oe ponies s . 1 lb. eb 1.15 Tonbo i é 16 = =T “from eggs, soluble scales.......--+- _... Merck White Label i ee eb - ae va 1 Ib. cb 1.10 Tonms i i wb heneunht tite Merck White Label: 1 lb. eb 1.00 Tonyt Aleohol Anti, ae Ce Be peu aniaed ‘Merck White Labei 1 lb. eb 1.45 Tooeh “ gh ee Ee bei at aaeenansna . Baker Analyzed ' 4ozeb ~ -65 © Toomr c. p. (Is0) . 0... eee eee | ; Tie ok 202 Toph 5 lb. ch 9.30 Toorg, AW CR. Pn Us RR H. T H O M A 8S Cc OO. M P: Ay -N -% Item Maker or Brand Size pkg. Price Code Word Alcohol Amylic for milk analysis................. Baker Analyzed 1 lb. eb 1.51 Tooys 5 lb. cb 6.85 Topao as PaCS eae eee ALT Hea Lat ara ae Merck Blue Label 4 oz. cb 1.20 Topha 1 lb. cb 4.00 Topku a ““ for fat determinations........... Merck Blue Label 4 oz. cb 1.00 Topsd 1 lb. eb 3.50 Toghz fo” BREN Zy Rises eee dn Wemiere Aaerase Malla naan Pfanstiehl 1 oz. eb -30 Togse 1 lb. eb 3.00 Toquy > SBuUtylli@.:hc ul. cone een teers cea eee dance Merck White Label 1 oz. eb .35 Torfe 4 oz. cb 1.05 Torhy 1 lb. ecb 3.40 Torju a “normal refined By Palit’ Cou.co0t5, sida sees kd eek ees 4 oz. cb 28 Torph 1 lb. cb 84 Torsb Ee S CAPE MCs s i aceeac cere ee RRS RR eL RR rn 1 oz. cb 1.50 Tosal ‘© b-Diethylaminoethyl ................... Pfanstiehl 1 oz. cb 2.00 Tosmn 1 lb. eb 29.00 Tosot so CBthyldenatureds: so sicectand scant uhke tremeuee Gah areececee 1 pt. eb 30 Touml 1 qt. cb 50 Touog 1 gal. can 1.30 Toura 5 gal. can 6.00 Touvs E> onsHMeptyl: hocsck ee hohe ee eee Be Pfanstiehl 1 oz. cb 17.50 Tovce “Iso. Propyl, (Petrohol) 91-92%. 2... 00.0.0 cece 1 lb. cb .80 Tovlm 1 gal. en 3.60 Tovnh ee sf (Petrohol): 98799: occa GA Aen eae aot as 1 lb. cb 1.00 Tovyl 1 gal. en 4.60 Towbf “> “Methyl eabout-900puness snlakeeie bas. Tae ecae ane ae eat 1 pt. eb .40 Towir 1 qt. cb -65 Towpe 1 gal. can 1.50 Towwo 5 gal. can 7.00 Towyk ‘ — 97-98.7% (Columbian Spirits).... ...............000. 1 pt. eb 50 Toxgu 1 qt. cb .80 Toxiq 1 gal. can 2.20 Toxkm 5 gal.can 10.50 Toxmi “s & 95 O77 TELNEdS %.o.s ids Soe eS Baker Analyzed 1 pt. cb .66 Toxyj 1 gal. cb 2.85 Toyaf = ce “absolute: eeu eet oreo Baker Analyzed 1 pt. eb -78 Toyhr 1 gal. cb 3.35 Toyjn te « **e, p.””, free from Acetone...... Merck White Label 1 lb. eb 80 Toypa 1 gal. cb 4.65 Toyts oe “AL P.., “‘e. p.’”’, as specially recom- mended for use in preparation of Wright’s, Hastings’ and Roman- owsky’s blood stains ............ Merck White Label 1 Ib. cb -70 Tozca fe “pure. In hermetically sealed glass GUDeN aces cns eae ak hres a trek eae Soloid 15 ml. tube 50 Tozjm s SE ohicrscsn ir Peete eae Cra eee ye eect ae Merck Blue Label 4 oz. cb -65 Toztr 1 lb. eb 2.00 Tozyh “ Octyl, Secondary, see ALCOHOL CAPRYDIG ec ace eee ee a ar he * “y=Propyl,, Pefined «ccs acai a teed de Pfanstiehl 1 lb. cb 2.10 Traep Aldehyde, 95% liquid (Acet-aldehyde)........... Baker Analyzed 4 oz. cb 58 Trakd 1 lb. cb 1.70 Tramz st Greene 62 cours w35 es See ee Coleman & Bell 10 gram gv 75 = Travg 25 gram gv_—ss:-1.60 Trebr INTIZATINEG Ls Coys Oe Ree nie oe ase ak aes Coleman & Bell 10 gram gv 90 Trehf 25 gram gv 2.00 Trens oy Carmine see ALIZARIN SODIUM MONOSULEONATE ait cick GGShaiee MeeOew ends Gamaaieki. hates f Sodium Monosulfonate, (Alizarine, Red 8) et ee ee Coleman & Bell 10 gram gv -90 Treve 25 gram gv 2.00 Tricl “s Yellow R, pH range 10.1-12.1........... Coleman & Bell 10 gram gv .75 Triky 25 gram gv_—s«i1.60 Trimr = Paste 20 Garaes cease ee eae ee eae Coleman & Bell 25 gram gb .50 Trise 100 gram gb_~—=s—:11.00 Triua Alkkalic BIWG2 ss. Schnee See es Eee Coleman & Bell 10 gram gv 90 Trobh 25 gram gv 2.00 Troeb Aloin, U.S. P., For “Occult Test” for blood in faeces Merck White Label - 1 oz. cb .20 Trokp Alpha Naphthol, see NAPHTHOL ALPHA....... 0 «0.6... oe eee “ Naphthhylamine, see NAPHTHYLAMINE ALPH. A R T H U R H. T H O M A SS Cc O M P A N'Y Item Maker or Brand Size pkg. Price Code Word Alum Ammonium, see ALUMINUM AMMONIUM . SULBAT Es sacs cacide eee ARERR MR eeRA Mee: 8 © kee eek 6 Lee “Burnt. see ALUMINUM POTASSIUM SUL- . FATE CALCINED....... Ro, Guoialiauetaraees, Cotalicdaliia, hashed eo “Carmine, SOMO: ieee weaned Ree a eta eee 8 1 oz. cb 40 — Troge 8 oz. cb 2.50 Trosy “Hematoxylin, solution. . 0.0.02... 00 ee eens 1 oz. eb 50 Truad 8 oz. cb 3.00 Truev Alumina Levigated! Grade No. 1. For all hard Metals: Sr. cited ers Feeae wees a> WA WARLA DA SRA ae omens 1 oz. 100 Trukj ' Levigated? Grade No. 2. For medium hard : metals nc iecigiaKsseesSisaee ena orumieetas ‘Loz. 1.40 9 Truru “ Levigated® Grade No. 3 For very soft metals and for research work under highest magnifications... ................6.. 1 oz. 1.80 Truze Aluminium. see ALUMINUM...............06600 cee e eee eee eens S miasnencs!, Creat : Aluminum Metal, Filings. ........... 2.0000 cece ete eee eee tenes 4 oz. cb 34 8 Tryfp 1 Ib. eb 1.11 Tryhl “ ** Foil .001” thick by 6” wide... 6... eee eee eee eee 1.oz. pkg 25 Tryny 4 oz. pkg 65 Trypu 1 Ib. pkg 2.10 Tryrq a “granular, 30 mesh............. Baker Analyzed 4 oz. cb 52 Tryxe 1 Ib. eb 1.26 8 8©Tryyc 5 lb. eb 5.65 Tuaar 10.Ib. cb 10.80 Tuadl te S SMOSS Yes g 2 Si ek mead teed ae Baker & Adamson 4 oz. ctn - 24 8 Tuakex 1 Ib. etn 76 Tuamt ss “oe. Diy powder; {ME i ess cceescead seeieerrardea rae 4 oz. can 57 Tuauc _ 1LIb. can 1.85 Tuawy 18 Sticks v5.2 sd aecwes weeeeadseren Baker Analyzed 4 oz. can 42 Tubei 1 Ib. can 1.20 Tubhe es “ No. 24 B. &S. gauge 0.02”. In : sheets 12” wide by 72” long sold only in 12” widths, about 5 oz. \ per sq. ft. Other sizes on special OFOEP 3 eds hnchipt Pacman ceee wy HOARSE SeeRT EM eS —Atb. 1.06 Tubpl = “turnings ..............- eee Baker Analyzed 4 oz. can A2 Tucap 1 Ib. can 1.20 = Tuceh.. ms Wire, see APPARATUS CATALOGUE ............-....-- i) bee oles ee Acetate, c. p., basic powder........... Baker Analyzed 1 oz. eb - 18 Tucno 4 oz. cb AT = Tucgi 1 Ib. eb 1.35 Tucse a fo CPs hccuh ewes take eee eee Baker & Adamson 4 oz. cb 38 Tudao 1 Ib. cb 1.31 Tudck “ ium Sulfate, U. 8. P., lumps... Merck White Label 1 lb. etn 2100 Tudku ey ee j - -Blbctn 1.00 Tudmag s © Ui. Se Pi powder... ..6seeiee eee nos 1 Ib. etn 20 Tudyr 5 Ib. etn 75 Tuean is “ 7 . p. tals... .. Baker Analyzed 4 oz. cb 24 Tuegd ce 1 Ib. cb 56 Tuete 5 Ib. eb 2.25 Tuekt “s Epos Baker & Adamson 4 oz. cb 15 = Tuere 1 lb. cb 39 = Tueta , 5 lb. eb 1.65 Tuexs ee i ., crystals... 0.20... eee Baker Analyzed 1 oz.'eb 15 Tufga Chloride, ¢. p., erystals on eb 32 Tyfiw 1 Ib. eb 84 Tufks 5 Ib. eb 3.65 | Tufmo - / 25 Ib. crock 15.75 Tufoj “ “ Giant Baker & Adamson 4 oz. cb 27) Tufer a 1 Ib. cb "88 Tufzn _ 5 lb. ch 4.10 Tugch “ ee c. p., sublimed........-----+ Baker & Adamson : 4 oz. cb 43 Tugkr 1 lb. eb 150 Tugmn 1In using this material, grinding can be stopped on the No. 00 emery paper, 1 oz. of solid alumina and 49 ozs. of distilled water gives in araneaina: brass bronzes and all copper and nickel alloys. 1 oz. of the’solid alumina and 99 ozs. of distilled water gives 100 ozs. of correct polishing solution. *The polishing is done somewhat more slowly ozs. of correct polishing solution. than with grade No. 2. 1 oz. of solid alumina and 166 ozs. of distilled water gives 167 11 A R T H U R H. T H O M A _ S c oO M P,. A’ NY Item Maker or Brand Size pkg. Price Code Word Aluminum Chloride, c.p., anhydrous............. Baker Analyzed 1 oz. gb .24 Tugty 4 oz. gb 52 Tugvu 1 lb. gb 1.30 Tugyo 5 lb. gb 5.25 Tuhak . 2x5 lb. gb 10.00 Tuhde 25 lb. crock 22.00 Tuhfa 50 lb. crock 43.00 Tuhiu — Fluoride, c. p., powder............... Baker Analyzed 1 oz. cb 19 Tuhrb 4 oz. cb -50 Tuhot 1 Ib. cb 1.44 Tuhxp os Hydrate; Uc S2Bok ce ccs ae cietaecans Merck White Label 1 Ib. eb AT Tuieb oe Me c. p., powder............... Baker Analyzed 4 oz. cb 34 Tuiln 1 Ib. eb 91 Tuini < oe GC p......-....-........... Baker & Adamson 4 oz. cb .27 Tuivs 1 Ib. cb -88 Tuixo 7 Nitrate, c. p., crystals................ Baker Analyzed 4 oz. cb .34 Tujfy 1 lb. eb 91 Tujis 5 lb. cb 3.95 Tujko 10 lb. cb 7.30 Tujmk a & -@, ps crystalss.. cnx ncage ea ven. Baker & Adamson 4 oz. cb .30 Tujyl 1 lb. cb 1.00 Tukez — Oxide, technical, powder (Hydrate) Baker Analyzed 1 lb. eb -50 Tukry “ ““¢e. p. (Ignited) powder......... Baker Analyzed 4 oz. eb Al Tukzi 1 Ib. eb 1.12 Tulbe iad See SCD) aie Sic Sh teen batch acre ms eerste doe Baker & Adamson 4 oz. cb 32 Tuljo 1 lb. cb 1.09 Tullk se Phosphate, c. p., Dibasic Secondary.... Baker Analyzed 1 oz. eb 19 Tulsv 4 oz. cb 50 Tumaf 1 lb. eb 1.44 Tumjn Potassium Sulfate, U. S. P., crystals, (Potassium Alum)... ................4-. 1 Ib. ctn 22 Tumpa 5 lb. etn .85 Tumsu c - 2 Us Si Pipowdercc. -s:.s0se gene ates 1 lb. etn 23 Tumeg 5 lb. ctn -90 Tunca ne es mn c. p., fine crystals... Baker Analyzed 4 oz. cb .27 Tunio 1 lb. eb .67 Tunli 5 lb. cb 2.75 Tunob 10 lb. cb 5.10 Tunrv 25 lb. keg 11.50 Tuntr ee ss “ Chie ed eee es Baker & Adamson 4 oz. cb 19 Tuoad 1 lb. cb .49 Tuodx 5 Ib. cb 2.10 Tuoft re Sodium Sulfate, c. p., crystals (Sodium ANU) 0 sb hehe ew Baker Analyzed 1 oz. cb 15 Tuolh 4 oz. cb .33 Tuone 1 lb. ecb 86 Tuopy 5 lb. cb 3.65 Tuotq o us sh D kira Roa taees oo oU eeu Baker & Adamson 4 oz. cb .25 Tupac 1 lb. cb 79 Tupcy 5 lb. eb 3.65 Tupho oy Sulfate, technical.................... Merck White Label 1 lb. etn 20 Tupoz 5 lb. ctn 65 Tupsr oy © “expa crystals oc oh telus Behe aa ees Merck Blue Label es Arsenate, c. p., crystals............. Baker Analyzed es Bicarbonate, c. p., powder............ Baker Analyzed te xs ChDusss Abe Baker & Adamson tf Bichromate, c. p., crystals........... Baker Analyzed “ e C) Dao sesauged eee Baker & Adamson os Binoxalate, c. p., erystals............ Baker Analyzed . Bisulfate, c, p.. crystals ............ Baker Analyzed ne Bisulfite, c. p., erystals.............. Baker & Adamson ft as c. p., cone. solution......... Baker Analyzed i “ep, solution..........-... Baker & Adamson fe Bitartrate, c. p., erystals.........-... Baker Analyzed 7 Borate, ec. p., crystals... udmene teas: Baker Analyzed 13 Cc O M P A N Y Size pkg. Price 1 lb. gb 1.05 2 Ib. gb 1.50 5 lb. gb 3.00 5 lb. can 2.15 1 lb. gb 1.30 2 Ib. gb 1.95 5 lb. gb 3.70 1 Ib. gb 1.30 2 lb. gb 1.95 5 lb. gb 3.70 1 lb. gb 1.30 2 lb. gb 1.95 5 lb. gb 3.70 10 gram gv _.B0 25 gram gv—s-11.10 30 grameb _.75 8 oz. cb 5.50 80 gram cb -75 8 oz. cb 5.50 30 gram cb -40 8 oz. cb 2.75 lozch _—cI 4 oz. cb 32 1 lb. eb 86 5 Ib. cb 3.65 2x5lb.cb 7.10 5x5 lb. cb = 17.25 4 oz. cb .30 1 Ib. eb 1.00" 5 Ib. cb 4.70 4 oz. gb 45 1 lb. gb 1.15 1 oz. cb 24 4 oz. eb 70 1 Ib. cb 2.08 4 oz. cb -26 1 lb. eb -62 4 oz. cb .23 1 lb. eb 70 4 oz. ch 56 1 Ib. eb 1.64 5 Ib. cb 7.50 4 oz. eb 51 1 Ib. eb 1.85 1 oz. cb 23 4 oz. cb 02 1 lb. eb 83 4 oz. eb 59 1 lb. cb 2.14 ‘402. go 41 _ 1b. gb -95 5 lb. gb 3.85 2x5 lb. gb =: 77.50 4oz.gb * .34 1 lb. gb 1.14 1 oz. cb 21 4 oz. cb 58 1 lb. eb 1.70 1 oz. eb 17 4 oz. cb 45 1 lb. eb 1.26 Code Word Tutke Tutsn Tutuj Tutyb Tuufn Tuuhj Tuukd Tuutk Tuuwe Tuuya Twig Tula Turn Tuvof Tuvyz Tuwif Tuwmx Tuwti Tuwve Tuxgi Tuxor A R YT A UW R H. T H O M A _S Cc OO M P A CON LU Item Maker or Brand Size pkg. Price Code Word Ammonium Borate, ¢c. p...............02-00000 Baker & Adamson 4 oz. cb 31 Twoza 1 lb. cb 1.05 Twubr . Bromide, c. p., powder.............. Baker Analyzed 1 oz. eb 16 Twuhf 4 oz. cb 38 Twujb 1 lb. eb 1.05 Twulx ss Carbonate, U.S. P., lump........... Merck White Label 1 Ib. tin Al Twurk 5 Ib. tin 1.30 Twuve = nf UsSePi ccubess.isc.4 7oee Merck White Label 1 lb. cb 55 Twyel 5 lb. cb 2.50 Twyeh i in c.p.,lump.............. Baker Analyzed 4 oz. cb .26 Twymr 1lb. cb -62 Twyom 5 lb. cb 2.55 Twyqi 10 lb. eb 4.70 Twyse 25 lb. can 10.50 Twyua 50 lb. can 20.00 Twyxru - i: CRD ora eeeaar ona nA nose Baker & Adamson 4 oz. cb 17 Tyaeb 1 |b. eb -46 Tyagx 5 lb. cb 2.00 Tyait me y Gi Ps CUDES ss shee eis Baker Analyzed 1 lb. ecb .84 Tyaog 5 lb. cb 3.40 Tyaqe : BED Ce seinetae iene a einen trent ened Merck Blue Label 4 oz. gb .30 Tyazk 1 |b. gb -70 Tybbg 5 lb. gb 2.25 Tybea sy Carminate:s so5c44 save, Aaa Aas Coleman & Bell 1 gram gv 45 Tybmk 10 gram gv =: 2.00 Tybof a Chloride, technical granular 94-96% (SalAMMOnaC)ie ska stan. Ait wea esate ddd 1 |b. .34 Tybzj 5 lb. 1.45 Tycez 25 lb. 6.50 Tycir a “U.S. P., “ce. p.,” granular..... Merck White Label 1 Ib. etn 37 Tycry 5 lb. ctn 1.60 Tycus of “@p pj etantlars..cocse.5 ehee aoe Baker Analyzed 4 oz. cb .25 Tydbe 1 Ib. cb 61 Tydey 5 lb. eb 2.40 Tydhs 25 lb. keg 9.75 Tydjo 50 lb. keg 19.00 Tydlk te Si WGI a orate suntan ea as Baker & Adamson 4 oz. cb 21 Tydur 1 lb. eb .64 Tydyj 5 lb. eb 2.90 Tyeaf ts ee) GaLRA Re Cate ed ag tan tee Merck Blue Label 4 oz. cb .30 Tyehr 1 lb. eb .75 Tyejn 5 lb. cb 3.00 Tyelj . “ce. p., granular free from Aniline Derivatives........ Baker Special 4 oz. cb 32 Tyesu 1 Ib. eb 84 Tyeug 5 lb. eb 3.45 Tyewm « Chromate, c. p...............000005 Baker Analyzed 1 oz. cb 24 8 8Tyfdy 4 oz. eb 68 Tyffu 1 lb. eb 2.04 Tyfio SS neutral. 2 eae cent Merck Blue Label l’oz. eb 40 8 Tyfst 8:02. cb 2.25 Tyfup Citrate, c. p., erystals............... Baker Analyzed 1 oz. eb 24 Tyggr 4 oz. cb -68 Tygin 1 Ib. cb 2.03 Tyglh e Fluoride, c. p., crystals.............. Baker Analyzed 8 oz. wb 1.29 Tyguo ss CED ccc ae! Moe ee Baker & Adamson 8 oz. wb 1.19 Tyhba “ te Merck Blue Label 1 oz. cb 30 Tyhjk oe ep 60 Tyhlg 0z. ¢ 1.50 Tyhnb 5 Formate, c. p., crystals.............. Baker Analyzed 4 oz. cb 52 Tyhol 1 |b. eb Hydrosulfide (Sulfhydrate) see AM- : ist tate MONTUMGSULEIDE his cintuaetiewerssa Rath veces Ammonium Hydrate, 20° (17.5% Ammonia)...... ................... 4 lb. eb 96 = Tyifr -lb. ed bottles, at 28¢ per lb..... ain pala cork stoppered bottles, at 23c per lb \ keene enn een rig eee 11.20 Tyihn Ammonium Hydrate, c. p., sp. gr. 0.90........... Baker Analyzed 1 lb. gb 43° Tytoy ‘ lb. gb -64 Tyirs = : gb extra 50 f ten 4-Ib. glass st: bottles, at 1 Ib... Bogie o eeecs Sesame enya eres! alos ate 401b. case 1260 Tyito Carboy, approx. 90 Ibs.,at13c per Ibe ee eee (2028s carboy 11.70 Tyivk carboy extra 6.00 A R T H U R H. Wee CE Os = ANS aA 1S Cc O M P A N Y ; Item Maker or Brand Size pkg. Price Code Word Ammonium Hydrate, c. p., sp. gr., 0.90.......... Baker & Adamson Ve lb. gb .66 Tyjdu In case of ten 4-Ib. glass st d bottl ed a 1D. ass sto ie Glass bottles, at ane peck, enttay ee. ei eee ae i ODL ORAS LR Sie Gra ee a ta 40 lb. case 11.90 Tyjgo Ammonium Hydrate, c. p., free from Pyridine..... Baker Special \ lb. gb .84 Tyjnz In case of ten 4-Ib. glass st d bottl eae hi en 4-10. ass Glass bottles, at Bde each. ries cies: ui es paras \ TRB eae SS Sap te Sane Spcakat 40 lb. case 14.60 Tyjsp Ammonium Hydrate, 10° (Ammonia Water)..... Merck Blue Label 1 lb. gb .65 Tykhl 7 j 4 |b. gb 1.75 Tykkf «© 20% (Ammonia Water)..... Merck Blue Label 1 lb. gb .70 Tykrq _ 2 oe : 4 lb. gb 2.00 Tykim 28°. (Ammonia Water)..... Merck Blue Label 1 lb. gb .75 Tylay e : 4 lb. gb 2.20 Tylds MOUIdE Cosh ter Aces sc niet ae et ete Baker Analyzed 1 oz. cb 57 Tylke Molybdate, c. p., crystals........ Baker Analyzed 1 oz. cb .32 Tylma 4 oz. cb 98 Tylov 1 lb. cb 3.00 Tylqr 5 lb. eb 14.10 Tylsn 10 lb. cb 27.30 = Tyluj 25 1b. keg 66.25 Tylad 50 lb keg = 129.00 Tymax 3 C. ps Crystals’, 0. cs .ckou ss Baker & Adamson 1 oz. cb 31 Tymgl 4 oz. cb 1.15 Tymih 1 |b. cb 4.41 Tymlb ta crystalsdont enw oso e oe Merck Blue Label 4 oz. cb 1.60 Tymut Fs ms ee : 5 1 |b. cb 6.00 Tymwe Nitric Acid Solution (For Phosphorus Determination According to Blair)....... Baker Analyzed 1 lb. gb 1.62 Tynes we 3 c. p., Nitric Acid Solution. Baker & Adamson 1 lb. gb 1.50 Tynje ss = Merck Blue Label 1 oz. cb 45 Tynpr 4 oz. cb 1.60 Tynsl 8 oz. cb 3.00 Tynuh 1 Ib. cb 5.50 Tyny2 a Nitrate, purified, granular...........0 22... eee eee eee 1 lb. eb .36 Tyofl 5 lb. cb 1.35 Tyoif os “ —e.p.,granular.............. Baker Analyzed 4 oz. cb .32 Tyoos 1 lb. cb 82 Tyoqo 5 lb. cb 3.45 Tyosk 2x5 lb. cb 6.60 Tyoug 25 lb. keg 14.75 Tyowce 50 lb. keg 28.00 Typau “ CNDe le be Ss BS Baker & Adamson 4 oz. cb .25 Typie 1 lb. eb .80 Typlu e a 5 lb. eb 3.70 Typor Re Reus eng ae Pn er eee Merck Blue Label 4foz. gb 50 Tyqat 1{lb. gb 1.35 Tyqdn 5,lb. gb 5.50 Tyqlx ee Oxalate, pure...............--.005- Merck White Label 1 lb. cb .80 Tyqoq * a c. p., erystals............-. Baker Analyzed 1 oz. cb 16 Tyquwa 4 oz. cb 41 Tyqeu| 1 lb. cb 1.15 Tyrbq 5 lb. ecb 5.10 Tyrdm 10 lb. keg 9.80 Tyrfi 25 lb. keg 22.50 Tyric . EOD Ge Didsticea nc eiue Seale Glavanns Baker & Adamson 4 oz. cb 36 0 86 Tyrpn 1 lb. eb 1.24 Tyrsh 5 lb. cb 5.90 Tyrud ce SRS han aA Gis ah Dae eine Merck Blue Label 4 oz. cb 40 Tysdl 1 lb. cb 1.25 Tysfh 5 lb. cb 5.25 Tysid % “ ep. erystals........---55- Baker Special 4 oz. cb 54 Tyssg 1 lb. cb 1.57 Tysuc Perchlorate, c. p., crystals.........--. Baker Analyzed 1 lb. eb 91 Tytbo 5 lb. eb 3.95 Tyter Persulfate, c. p., crystals.........--- Baker Analyzed 1 oz. eb 17) 2=-Tytms 4 oz. cb 43 Tyton 1 Ib. cb 1.17 Tyisf 5 lb. cb 5.30 Tytyt 10 lb. cb 10.20 . Tyuap 25 lb. keg 23.50 Tyucl . 50 lb. keg 45.00 Tyugd 15 A R T H U R He: T H O M A S Cc O M P A N _ Y Item « Maker or Brand Size pkg. Price Code Word Ammonium Persulfate, c.p..................--. Baker & Adamson 4 oz. cb 38 Tyuno 1 lb. cb 1.31 Tyupk 5 lb. cb 6.25 Tyurg Ci EES de hppa neues MSD PEN Merck Blue Label 4 oz. cb 60 Tyuys 1 lb. cb 1.80 Tyvao 5 lb. cb 8.50 Tyvek = Phosphate, c. p., crystals Monobasic H,) H,PO, Primary.... Baker Analyzed 4 oz. cb A7 Tyvku 1 lb. cb 1.33 Tyvmq 5 lb. cb 5.95 Tyorf s e c. p., Dibasic (NH,),HPO, (Secondary)iocccac eu Lasa 4 Baker Analyzed 4 oz. cb 43 Tyvzep 1 lb. cb 1.19 Tywbl 5 lb. cb 5.30 Tywef 10 lb. eb 10.20 Tywix 25 lb. keg 23.50 Tywre ye c. p., Dibasic ang yee (Secondary) . ..... Baker & Adamson 4 oz. cb 37 Tyweo 1 Ib. eb 1.29: Tyxci 5 lb. cb 6.15 Tyxhy ML Nlibes ARREARS Merck Blue Label 4 oz. cb .50 Tyxoj 1 lb. cb 1.50 Tyxtz ey Phospho-Molybdate, c.p............ Baker Analyzed 1 .0z. cb 1.05 Tyybj > Potassium Tartrate, c. p., crystals..... Baker Analyzed 1 oz. cb .25 Tyyha 4 oz. cb 73 Tyyjt 1 lb. cb 2.20 Tyylp = Sulfates pure-ss.4 o0c.cce.s ee OR a Merck White Label 1 lb. etn .33 Tyyty 5 lb. etn 1.50 Tyyvu = oe Cap; Crystalse.. i. eecat ails Baker Analyzed 4 oz. cb .24 Tyzec 1 lb. cb .56 Tyzgy 5 lb. cb 2.25 Tyzjs 10 lb. eb 4.10 Tyznj 25 lb. keg 9.00 Tyzrb 50 lb. keg 17.50 Tyzyn i a c.p.. Baker & Adamson ‘4 02. eb 16 Tzaht 1 lb. cb 44 Tazjp 5 lb. cb 1.90 Tazmj 1 OBO MR eh hig POO ohn GNP tne nN Merck Blue Label 4 oz. cb .30 Tzaus 1 Ib. cb 75 Tzawo 5 lb. cb 3.25 Tzayk a “ c. p., erystals Pyridine free... Baker Special 4 oz. cb 32 Tzeft 1 lb. cb -82 Tzehp e Sulfide, (Hydrosulfide) dark solution.. Baker Analyzed 1 Ib. gb .52 Tzepy 5 lb. gb 1.75 Tzevm Cine Howls arabe eae cree ance ab Sr 00 este 50 lb. case 17.50 = Tzexi Carboy, 100 lbs., at 20c per Ib. ae lb. carboy 20.00 Tzeze carboy extra 6.00 Ammonium Sulfide, (Hydrosulfide) light solution.. Baker Analyzed 1 lb. gb 52 Tzihl I f ten 5-lb. glass st d bottles, at 21 Ib.....) oueee ae teas (Glace battles, ak Sle cach exore; ease et @.0N eta, ee ee 50 lb. case 17.50 = Tzild Carboy, 100 lbs., at 20c per lb. ee lb. carboy 20.00 Tziny carboy extra 6.00 Ammonium Sulfide, solution.................... Merck Blue Label 4 oz. gb -40 Tzitm 1 lb. gb 1.00 Tzivi Sulfite, c. p., crystals... ............ Baker Analyzed 1 oz. cb 15 Tzobr 4 oz. cb .36 Tzodn 1 lb. eb 98 Tzofj “ “¢e.p., erystals............... Baker & Adamson 4 oz. cb .38 Tzolx 1 lb. eb 1.31 Tzons Ls Sulfocyanate, see AMMONIUM WTO CYANATT HS wes ao tie ieee athoeso MB Peele i ie Sulfocyanide, see AMMONIUM THIOGVANA TE: Mat te eheeeiaheaa nnackace poten a Tartrate, c. p., crystals.............. Baker Analyzed 1 oz. eb 19 Tzove ; 4 oz. cb 51 Tzoxry 1 lb. eb 1.47 Tzuan “s ef CIDE: SA red wt oh date na at es Baker & Adamson 4 oz. cb 43 Tzuhz 1 lb. cb 1.50 Tzujv 16 A R T H U R H. Te 3H Os GME AS 3S) Cc O M P A N_ Y Item Maker or Brand Size pkg. Price Code Word Ammonium Thiocyanate, c. p., crystals (Ammon- ium Sulphocyanide or Sul- phocyanate)........... Baker Analyzed 1 oz. cb 21 zupi 4 oz. cb 57 Tzuse 1 lb. cb 1.70 Tzuwu 5 lb. cb 7.80 Tzeuyq 2x5 lb. cb 15.00 Tzyaj 5x5 lb. cb 36.50 Tzyeb i 10x5 lb. ch 72.00 Tzytt c. p., (Sulfocyanate) Baker & Adamson 4 oz. cb 7 Tzype 1 lb. eb 2.07 Tzyra VAN AGA $6 oe ee Se ees Uddnov “ “6 lizable, water white..............-------- 1 pt. can 40 Uddxb pute crystallize 1 gal. can 1.50 Udeav 5 gal. can 5.00 Udecr i estion of Dr. Dudley Roberts, see Journal of the American Medical Association, July 17 Coe Cee Best ate Sd One parts sodium perborate. Tablets should be used within six months because of some aie oF Deon PP paoled in boxes of five vials of twenty tablets each, with a bottle of glacial acetic acid with special stopper for applying the acid to the tablets. 21 A R T H U’'R H. T H O M A §& Cc O M P A N Y Item Benzol, (Benzene), c. p., Thiophene free.......... “ a“ Benzopurpurin 4B.............. 00.2.0 .000 eae Benzoyl Chloride, pure......................00 Benzosulfinide, see SACCHARIN .............. Benzoyl-sulfonic-imide, seeSACCHARIN ........ Benzyl Chloride, c. p., redistilled................ “* Malonic Ester..................0..000.. SO ViOle brs anecdote Re Se Beryllium Metal, powdered.................... oy Nitrate, pure....... betes eee ee “ Beta Naphthol, see NAPHTHOL BETA......... Biebrich Scarlet............0.0.0.00 00.000 cee eee ee Bile Medium, see LACTOSE PEPTONE BILE DEHYDRATED................. Biondi-Ehrlich-Heidenhain, Triple stain.......... Bismark Brown Y.............-..00 00000 c ee eeee “cs “ pure 0.1 gram tablets............ “cc ‘ce Solution 5b. eb 11.70 Uemty 10 lb. cb 22.60 Uemou s “ —e. p., erystals.............,.. Baker & Adamson 4 oz. cb 78 Uende 1 lb. eb 2.92 Uenfa 5 lb. cb 14.30 Ueniu 7 me c. p., anhydrous powder...... Baker Analyzed 1 oz. eb 35 -o, Uenuv f 4.oz. cb 1.08 Uenal : 1 lb. eb 3.36 Ueobh ee i] c. p., anhydrous............. Baker & Adamson 4 oz. cb 1.12 Ueoit 1 lb. eb 4.26 Ueokp as HydratesCs picaven iene a ebbe hoes Baker Analyzed . 1 oz. eb 51 Ueoge i 4 oz. eb 1.64 Ueosy 1 lb. cb 5.24 Ueowgq a Jodide, c. p., erystals................. Baker Analyzed 1 oz. cb .57 Uepea 4 oz. cb 1.88 Uephu 1 lb. eb 6.00 Uepko *y Nitrate, c. p., crystals................. Baker Analyzed 1 oz. cb .26 Ueput 4 oz. cb 17 Uepyl 1 Ib. eb 2.33 Uegez - CS SCD oan oe a ea he Baker & Adamson 4 oz. cb 72 Uegqry : - 1 lb. cb 2.66 Uequs os Oxide, c. p., powder..............-... Baker Analyzed 1 oz. eb .60 Uerbe te Phosphate, c. p., powder.............. Baker Analyzed 1 oz. cb 68 Uerjo 24 A R T H U_R H. TH Oo M A S G70" My Ps A IN Item Maker or Brand Size pkg. Price Code Word Cadmium Sulfate, c. p., anhydrous.............. Baker Analyzed 4 oz. cb -86 Verge 1 lb. cb 2.64 Uersv ye bs Copsy CY Stal Seis eae tue Contes Baker Analyzed 1 oz. cb .26 Uesaf 4 oz. cb 17 Ueshr 1 lb. eb 2.33 Uesjn a PICA ceshat wacko amens ecm cce ya vale ay Baker & Adamson 4 oz. cb 72 Vespa 1 lb. eb 2.66 Uessu ee Daag errr eden cinte facta, Aedes Aaetee hpcan areas Merck Blue Label 1 oz. cb .30 Uetae 8 oz. cb 1.50 Uedty Cesium Metal, electrolytic... 90000 0.0000.00...0 2... qo gram gv 2.25 Vetli 1 gram gv 10.00 Uetob CHIOrId Genre Se Os eet, shen enrant O hit Nal cp met toate 1 gram gv -50 Ueucz 10 gram gv 4.50 Ueuft ae Nth ate ors eee ee ees Pfanstiehl 1 oz. eb 6.50 Ueumf Calcium: Metaliov.2 23 25.¢ 2524 eee eee Reine. gett Nach erardrates alain a 2 4 oz. tin 3.50 Ueuwk Me Acetate, purified, granular.............. 0.2... eee eee 1 lb. eb -60 Uevho 5 lb. eb 2.50 Uevki si oe C2 Pe ePOWGERs (eka on ed BOG A Baker Analyzed 1 oz. cb 15 Uevun 4 oz. cb 34 Uevyf 1 lb. eb 92 Uewab et BE CoO MiMi aise ts Gace eters a! Maal 14 pe ah eras oe Baker & Adamson 1 lb. cb 94 Uewhn - Arsenate, c. p., powder................. Baker Analyzed 1 oz. cb .30 Uewqu ee Bromide, c. p., erystals................. Baker Analyzed 1 oz. cb .23 Uewwi 7 Carbide, lumps about 3”... 0.00.6... 00. ce eee 2 lb. can -70 Uexgo “© Carbonate, lump (Marble).............. 0 ...---. 1 lb. etn 15 Uexox 5 lb. etn -47 Uextn 10 lb. etn -70 Uexxf 50 lb. etn 2.00 Ueyaz ss ss technical, precipitated....... Merck White Label 1 lb. etn 21 Ueykf 5 lb. etn .90 Ueymb 10 lb. etn 1.60 Ueyow = a (Iceland Spar) technical, lumps Baker Analyzed 1 oz. cb 17 Ueyvi 4 oz. cb -45 Ueyza 1 lb. cb 1.12 Uezcu s a c. p., powder............... Baker Analyzed 4 oz. cb 36 Uezma 1 |b. eb -98 Uezov 5 lb. cb 4.30 Uezsn 10 lb. eb 8.20 Uezuj 25 lb. keg =:18.75 Ufaav 50 lb. keg 36.00 Ufacr s ee c. p., free from Alkali........ Baker & Adamson | 4 oz. cb 32 Ufajd 1 lb. eb 1.09 Ufalz 5 lb. eb 5.15 Ufanu uf ee a er ea entire Pre cee Cera Merck Blue Label 4 oz. cb .30 Ufati 1 Ib. eb 75 Ufave ee Nate} netics 2 aly pa OO Pfanstiehl 1 oz. eb 1.00 Ufbie asus 1lb.cb 10.00 Ufbly . , technical, granular 70-75%, an- eae pyar . Eye oe ee ae ea oA att AG 5 Ib. can 70 Ufcat “ “ ified, fused 70 g Panny dross Masih gedit oan 1 Ib. tin 45 Uferk ee ae 5lb.tin 175 Ufeue oe oa ified, granular 72% anhy- Ec ns ba EEF ne rehie Gate aoa ays men meena nena ie 1 Ib. tin 45 Ufdfi 5 Ib. tin 1.75 Ufdic ts “technical, dried anhydrous, gran- h, for Desiccators.... Baker Analyzed 1 lb. cb 50 Ufdud ai erm Blb.cb 2.05 Ufear 10 lb. can 3.50 Ufedl 25 lb. can 7.75 Ufefh 50 lb. can 15.00 Ufehd 100 lb. can 29.00 Ufekx “ “technical, lump dried, pees. / eae ... Baker Analyzed 1 lb. eb -43 Ufesg for Desiccators . 5 Ib. cb 1.65 Dei 10 lb. can 2.90 Ufewy 25 lb. can 6.25 Ufezs 50 lb. can 12.00 Uffbo 100 lb. can =. 23.00 Uffei “ “ , for Desic- oe ee ee da te ate Baker & Adamson 1b. cb tw 85 Uffms Sanaa 5 lb. cb 1.45 Uffon 25 Ay Rey ote Sets CUE R: H. TT H O M A S Cc © M P A N ® Item Maker or Brand Size pkg. Price Code Word Calcium Chloride, c. p., anhydrous, dried, lump, pure white, for reagent use. . Baker Analyzed 4 oz. cb 32 Ufgeh 1 lb. eb -84 Ufglt 5 Ib. cb 3.60 Ufgom i is Cp erystals’.2%. 2.20. 6oe chee ee Baker Analyzed 4 oz. cb .24 Ufheg 1 lb. eb 56 Ufhha 5 lb. eb 2.25 Ufhku 10 lb. cb 4.10 Ufhol 25 lb. crock 9.00 Ufhyr a “ c. p., wet erystals............. Baker & Adamson 4 oz. cb 17 Ufief 1 lb. eb -46 Ufigb 5 lb. cb 2.00 Ufiizx t es c. p., anhydrous, granular 4’mesh, for drying tubes.............. Baker Analyzed 1 lb. cb 17 Ufiok 5 lb. cb 3.25 Ufire 10 lb. can 5.90 Ufita 25 lb. can 13.75 Ufizs 50 lb. can 26.50 Ufizo 100 Ib. can 50.00 Ufjga He ts ec. p., anhydrous, granular 8 ' mesh, for drying tubes......... Baker Analyzed 1 lb. eb -70 Ufjux 5 lb. cb 3.10 Ufkal 10 lb. can 5.60 Ufkiv 25 lb. can 13.00 Ufkoi 50 lb. can 25.00 Ufksa 100 Ib. can 48.00 Ufkyo ss By c. p., anhydrous, granular 12 mesh, for drying tubes......... Baker Analyzed 1 lb. eb -70 Ufiuy 5 lb. eb 3.10 Ufmaj 10 lb. can 5.60 Ufmit 25 lb. can 13.00 Ufmym 50 lb. can 25.00 Ufnea 100 lb. can 48.00 Ufnhu ee ec. p., anhydrous, granular 20 mesh, for drying tubes......... Baker Analyzed 1 lb. eb -70 Ufoah 5 lb. cb 3.10 Ufocd 10 lb. eb 5.60 Ufoez 25 lb. eb 13.00 Ufoht 50 lb. eb 25.00 Ufejp 100 lb. eb 48.00 Ufomj “e - technical, anhydrous, _ sticks, fuS@dh, esau emenheous cM rgen wey Baker Analyzed 1 Ib. eb 82 Ufotu se c. p., anhydrous, sticks, fused... Baker Analyzed 4 oz. cb .38 Ufozi 1 lb. eb 1.05 Ufpbe fs ** Cu Ds, SStICKS 3 foie tn se tontees Baker & Adamson 1 |b. cb -69 Ufplk ms ie Crystalsintu cer demaie sewers ioe oi Merck Blue. Label- 4 oz. gb .30 Ufpyj 1 lb. gb 65 Ufgex fs ne dry, granular................. Merck Blue Label 1 Ib. eb -65 Ufrew ce neutral, crystals.............. Merck Blue Label 4 oz. gb 35 Ufsev 1 lb. gb 85 Ufsoa BS Chromate, c. p., powder................ Baker Analyzed 1 oz. eb 24 Ufteu ee Citrate, c. p., powder. . ......... Baker Analyzed 1 oz. ecb -27 Uftoz fe Fluoride, Native powder Goucad oki Send ty cn i re AOR orn rr raha 1 lb. etn 18 Ufucz 5 lb. etn 57 Ufuet 25 Ib. etn 2.00 Ufugp ss # CPs, POWER a5 34 tenn cede nes Baker Analyzed 1 oz. cb 19 Ufuna 4 oz. cb 82 Ufurs 1 Ib. eb 1.51 Ufuto ue - CAD tee a ae ee Ne Baker & Adamson 4 oz. cb 39 Ufuze 1 lb. eb 1.35 Ufvik ee Formate, c. p., crystals................. Baker Analyzed 1 oz. cb 24 Ufwaz 4 oz. cb -68 Ufwij 1 Ib. eb 2.02 Ufwow a Hydrate, pure, powder (Slacked Lime) Baker Analyzed 4 oz. eb -26 Ufaxke 1 lb. cb 65 Ufxov 5 Ib. eb 2.65 Ufxyb ef aA a aA Ges epider Rat tl Regt ne aa Baker & Adamson 4 oz. eb 20 Ufyfn 1 lb. cb 59 Ufyhj 5 Ib. eb 2.65 Ufyif oe COS ed ane en eh Tere aan ai ee rern ae Merck Blue Label 4 oz. cb -30 Ufyro 1 Ib. eb -65 Ufytk * Hypochlorite, (Oxychloride). (Bleaching Powder) (Chloride of Lime) ..............6.... 12 oz. can 15 Ufzaw A R T H U_ R H. T H O M A SS Cc oO M P A N Y Item Maker or Brand Size pkg. Price Code Word Calcium Hypochlorite, (Chlorinated Lime) cubes, for generating Chlorine.... ................... 1 lb. cb 45 Ufzla 4 oz. cb 15 Ufzot BS c. p., powder (Oxychloride). Baker Analyzed 4 oz. cb .33 Ugadn. 1 lb. eb .88 Ugafj (Cea) OSA eae Ee aS, Se aoe Baker & Adamson 4 oz. cb .28 Ugalx 1 lb. eb 92 Ugans es Todideycipacen aaa ae eae Baker Analyzed 1 oz. cb .83 Ugatg me —DactateU.S.Pis powder, aac ie A ee ee ee ee 4 oz. cb 30 Ugbco 1 Ib. eb .80 Ugbhe oe Nitrate, ce. p.; lump: 5 40528 Bees Baker Analyzed 1 oz. eb 15 Ugbud 4 oz. cb .32 Ugcar 1 |b. cb 82 Ugceej 5 Ib. cb 3.45 Ugelv a SEP SQINDH, Gaasntyantheapet Ue-mancae sateen Baker & Adamson 4 oz. cb .24 Ugezs 1 lb. cb 76 Ugdbo 5 lb. cb 3.50 Ugdge os Oxalate, c. p., powder.................. Baker Analyzed 1 oz. cb 19 Ugdyt 4 oz. cb .80 Ugeap 1 Ib. cb 1.44 Ugeel os ye OD reas reat een partition Baker & Adamson 4 oz. cb 14 Ugekv 1 Ib. cb 1.55 Ugemr ne Oxide, (Lilly’s Lime) For making lime water U.S. P., free from impurities present in ordinary lime. The contents of one vial added to one gallon of cool distilled water will make strictly U. S. P. lime water... Eli Lilly Co. vial 15 Ugese ce “ U.S. P. (Caustic Lime).......... Merck White Label 1 lb. eb 46 Ugezq 5 lb. eb 1.85 Ugfeg co “* (From Marble) lump............ Baker Analyzed 1 |b. eb .32 Ugfol 5 lb. cb 1.15 Ugfyr 10 Ib. can 1.90 Uggef 25 lb. can 4.50 Uggix 50 lb. can 7.00 Ugglr 100 Ib. can 12.00 Uggnm “© (From Marble) pure............. Baker & Adamson 1 lb. cb 29 Ugguy 5 lb. cb 1.45 Uggya OE asa beh tthe d enetore lunceih in Se Mere Merck Blue Label 4 oz. cb .30 Ughiw 1 lb. cb -60 Ughmo a ‘‘ Hydrated, see CALCIUM HY- DRATE 2 sayeoka Begetiniseeeeeey Aieeteee ities me Oxychloride, see CALCIUM HYPO- CHEORITE: 2 uweriie gto deeweeees Ghatnaied. “Nitrates. Co Dies diese dasa e eee Get Shred ee 1 oz. cb 2.60 Uhnea > “Oxalate: Us Si Piis-s0-5 pp SARE Ga) CEA Ee ee 4 oz. etn 22 Uhnjm 1 Ib. etn .70 Uhnnd Ch 1, for blowpipe, approx. 4}xlx$ inches......0 ©. 2... . see eee 1 pkg 12 pes. 1.10 Uhnup RECO OE PM EE aera as 12pkg144pes.10.56 Uhnay fe Animal, Tap See eR Ane ey TRO, teaayeeeeen Por a ere 1 lb. etn .24 Uhoev yee Blb.ctn 83.—« Uhogr 25 lb. etn 4.00 Uhoin es ins GOD Ane ARE ine PAU im a a hie aes 1 lb. ctn .25 Uhooa aay 5 lb. etn 1.00 Uhoru 25 lb. ctn 4.25 Uhovm “ (Bone) treated with acid and ist purified.......... Baker Analyzed 4 oz. eb 34 Uhpba waret ey 1 Ib. cb ‘91 Uhpew 5 lb. cb 3.95 Uhpim 2x5 Ib. cb 7.80 Uhpme < eee eesstse...... Baker Analyzed 1 oz. eb 21 Uhqab Blood, c.p.....-- Ae eb “88 hah 1 lb. cb 1.70 Uhdlif 5 Ib. cb 7.80 Uhqna “ ep eA e. hee eee a me tene) 1 lb. pkg 10 © Uhquwi Wood, lumps......-- 5 lb. pkg 40 Uhrby iG « ten ential ae ate a ee 1 lb. pkg 140 Uhyiji Dea 5 lb. pkg .65 += Uhrme 25 lb. pkg 2.75 Uhrox AR TH UR HH: TF HAH © M A 5 Cc O M P A N Y Item Maker or Brand Size pkg. Price Code Word China:Blue;see-ANTEINE BIGUH 6 sog ec ceiceneies habGoeeeeheee wabiere: caiGaasgude adie ao 2 Clay ise@G RAO GDN etek cured tae hae ke nasi alomecer matey neo raed aie Sine Chloracetamide............................... Pfanstiehl 1 oz. cb -85 Uhryd 1 lb. cb 10.00 Uhsaz Chloral Hydrate, U.S. P., loose, crystals.......... Merck White Label 1 oz. cb .20 Uhsij 4 oz. cb 46 Uhsid 1 Ib. eb 1.55 Uhsny < Par attra Se cece nett Napa Ne eared mec termine aon tL: Merck Blue Label 1 oz. gb .30 Uhstm 8 oz. gb 1.25 Uhsvi Chioretone:: sc ah ea te re eee lab oem Hee eka eee 1 oz. cb 1.25 Uhteq Chloride of Lime,see CALCIUM HYPOCHLORITE ...................00 eee eee Chlorinated Lime, see CALCIUM HYPOCHLO- RIT Chlorine. Water sc ic008 28 Sdn ee cag oh oe ees Merck Blue Label 1 lb. cb 1.25 Uhima Chloroform; Ui Sx Poe 2ak 25 behind oho oR Ee Merck White Label 4 oz. cb -28 Uhtuj 1 Ib. cb 17 Uhuax 5 lb. eb 3.40 Uhuct - CRD raat wt Vee eet eee Cs Gene Baker Analyzed 4 oz. cb Al Uhujf 1 lb. eb 1.14 Uhulb 5 Ib. cb 5.10 Uhups 10 Ib. cb 9.80 Uhusm 5x5 lb. cb 24.00 Uhuvg a Ch Dien tee Sy et oeand Mem a ow repo Pacts Baker & Adamson 1 Ib. eb 1.05 Uhvbu 5 Ib. cb 4.95 Uhohi SP eR hatch eumesesiten Kool a Anatenancs mtn SAS Merck Blue Label 4 oz. gb 50 Uhvot 1 lb. gb 1.50 Uhorn 5 lb. gb 6.25 Uhvuh Cholesterin: ¢5p's cc250 5 hee ee ee we BS Pfanstiehl 5gramchb 1.93 Uhwos 1 oz. cb 8.00 Uhzau Chrome Alum, see CHROMIUM AND POTAS- SIUM:SULPATE iia ae nt aietbeiemy sxouiceed, Nabe Chromic Anhydride, se ACID CHROMIC....... ©... eee ee Chromium Acetate, c. p., basic.................. Baker Analyzed loz.cbh — .34 Uhxka 4 oz. cb 1.05 Uhxor : 1 lb. eb 3.26 Uhaxuf Y Bromide ic. Pi 2 ase: see adiiee oe eee Baker Analyzed 1 oz. eb 72 Uhyel io Carbonate, c. p., basic powder........ Baker Analyzed 1 oz. eb .30 Uhykz 4 Chloride, c. p., dry.................. Baker Analyzed 1 oz. cb .27 Uhyqm 4 oz. cb 79 Uhysi 1 lb. cb 2.39 Uhyve “ “ e@ p., 50% solution.......... Baker Analyzed 4 oz. gb -64 Uhzdm 1 lb. gb 1.72 Uhefi os Fluoride, c. p., powder............... Baker Analyzed 1 oz. eb 25 Uiadj 1 lb. eb 2.20 Uiahb os Hydrate, c. p., powder............... Baker Analyzed 1 oz. eb 21 Uiaom as Nitrate, c. p., dry, basic.............. Baker Analyzed 1 oz. cb .25 Uiavy 4 oz. cb 71 Uiays 1 Ib. cb 2.14 Uibao “s BS SCRAP Y hate Meal etta Nett toned co Baker & Adamson 4 oz. cb -67 Uibha 1 lb. eb 2.49 Uibku a “ —e@.p., solution 40%. .......... Baker Analyzed 4 oz. gb 47 Uibst 1 Ib. gb 1.16 Uibzep io Oxalate, c. p., powder................ Baker Analyzed 1 oz. cb .23 Vicix i Oxide, c. p., powder (Sesquioxide).... . Baker Analyzed 1 oz. eb .24 Uicuy 4 oz. cb -68 Uicxs 1 lb. cb 2.04 Uiczo ies Potassium Sulfate, crystals, (Chrome Alum)............ Merck White Label 1 lb. eb 37 Uidiw 5 lb. cb 1.35 Uidmo as es = c. p., erystals...... Baker Analyzed 4 oz. cb 30 Uidux 1 Ib. eb .99 Uidyp 5 Ib. cb 4.30 Uieal se . s CS DiadGn gre trotyats Baker & Adamson 4 oz. cb 32 Uiegz 1 lb. eb 1.09 Viejt 5 Ib. cb 5.15 Uielp ” Sulfate, c. p., 30% solution Baker Analyzed 4 oz. gb .36 Uiety 1 lb. gb 74 Uiews a EA? eNOS [Oe OI Yas o avanie aca nha ean Baker Analyzed 1 oz. cb 19 Uifec 4 oz. cb -52 Uifoy 1 Ib. eb 1.51 Uiflo Ss SES) Guano y aan ees Mike ei a EOE A arn Baker & Adamson 4 oz. cb 39 Vifal 1 lb. cb 1.35 Uigeb A R T H U_ R H. T H O M A _ S Cc O M P A N Y Ae Item Maker or Brand Size pkg. Price Code Word Chrysoidine Y............ ee er eee . Coleman & Bell 10 gram gv -50 Uigml ; : 25 gram gv 1.10 Uigog Cinchonine, Alkaloid, crystals....0.0.00.0.0.00..0 foc eee 1 oz. cb 87 Uigzk ; 4 oz. cb 3.20 Uihfy Cobalt, Metallic, granular, 98-99%... . ........ Merek White Label 1 oz. cb 55 Uihmk si > espa dree irom Nickell, :9¢ Ge hoe k, Laka pias we eames 10 gram gv 33.25 Uthor ‘“* Acetate, c. p., crystals................ . Baker Analyzed 1 oz. eb 31 Utidb 4 oz. cb -94 Uiimj 1 lb. cb 2.89 Uiipe 5 lb. cb 13.50 Uiiry a CEA Din Bas tate cit dee Pee hee ee _.. Baker & Adamson 4 oz. cb .79 Uiizi 1 lb. eb 2.95 Uijbe ‘* Ammonium Sulfate, c. p., crystals........ Baker Analyzed 1 oz. eb 38 Uijjo ‘Carbonate, c. p., powder........ ....... Baker Analyzed 1 oz. cb .60 Uijur ‘“ Chloride, c. p., erystals........... ...... Baker Analyzed 1 oz. eb .29 Uikip 4 oz. cb 88 Uikkl 1 lb. eb 2.70 Uikmh 5 Ib. cb 12.60 Uikoc e es CUDO neta ee Maney tozen © . Baker & Adamson 4 oz. cb .69 Uikak 1 lb. eb 2.55 Uilae ‘© Chromate, c. p., powder................. Baker Analyzed 1 oz. cb -60 Uilgs ‘© Hydrate, c. p., powder................... Baker Analyzed 1 oz. eb 53 Uilob Nitrate, c. p., anhydrous powder......... Baker Analyzed 1 oz. cb 34 Uilup 4 oz. cb 1.03 Uilyh 1 |b. cb 3.20 Uimad Se Ho Ga De Crystalse cons one danke 6 Baker Analyzed 1 oz. eb 27 Uimin 4 oz. eb 17 Uimmf 1 |b. cb 2.35 Uimoa 5 lb. cb 10.50 Uimru 10 Ib. eb 20.30 Uimai = sya teste Ps Oe eS eS AO Pas AES ee Merck Blue Label 1 oz. gb .35 Uineu 4 oz. gb 1.00 Uinho Pe “free from Nickel................ Merck Blue Label 1 oz. gb 50 Uinoz 4 oz. gb 1.50 Uinsr “Oxalate, c. p., powder................... Baker Analyzed 1 oz. cb 43 Uiobz 4 oz. cb 1.37 Uiodv 1 lb. cb 4.34 Uiofr © —Oxide;¢: p:,: pOWder. 222.52 2. e8sn eee Baker Analyzed 1 oz. cb 43 Uiomd 4 oz. cb 1.37 Uioqu 1 lb. eb 4.34 Uiosg ‘Sodium Nitrite, see SODIUM COBALTIC NETREDE ccetec sc beste) Biber eerie: pease “Giosiis ‘Sulfate, c. p., crystals...............---- Baker Analyzed 1 oz. eb 26 Uioye 4 oz. cb 17 Uipby 1 lb. eb 2.33 Uipes : CES CLOT ts os Sg ee pene nee oe aT Baker & Adamson 4 oz. cb 59 Uipnez 1 Ib. eb 2.15 Uipul Cochineal, Bugs... 02.002 fesse eee eee keen beer ree ee 1 oz. ctn 14 Uigld 4 oz. ctn 35 Uiqow 1 Ib. ctn 1.20 Uigso ce powder, technical.... 00.22.6050 0e 2 beret eens 1 oz. ctn 14 UVireu 4 oz. etn 35 Uireq 1 Ib. etn 1.00 Uirgm Collodion, U.S. P.........5---- 2 eee Merck White Label 1 lb. can 55 Uirsn a enero eehi ten Ms a eer igen Merck Blue Label 4 oz. cb .40 Uiset 1 lb. cb 1.00 Uisep Colloidal Iron, see IRON DIALYZED .......--- see eerste Colophony, se ROSIN. cjescvesse nese en heeds Bieta enn anes Colorimetric Determination of H-ion Concentrations. The indicators, both in standardized dry powderandin solution, stan dardized buffer solutions, standardized buffer mixtures, and color standards required in this work are listed throughout the catalogue under their respective chemi- cal names. For convenience they are listed and explained on pages 163 and 164 of the Apparatus section, and are grouped together in a special listing on page 102 of the Reagent section...... 0-6 -- 0s seer eres A R T H VU R HH: PEO IMP) AD 4S Cc Oo M P A N Y Item Maker or Brand Size pkg. Price Code Word Columbian Spirits, see ALCOHOL METHYLIC QO BST: Sars ec Sd a cpc§ ES es agit eat een en IE ah ce heey earn bog eee Congo Paper, see TEST PAPER... .... 0.0.0 bebe nee ~ Red AB enews les Coleman & Bell 10 gram gv 50 Uiteo 25 gram gv 1.10 Uithi 100 gram gv 3.85 Uitje 200 gram gv 6.60 Uitmy Se “ARGU aes ey tatvay erate seed men eth Ahn treed bt Merck Blue Label 4 oz. cb .30 Uituh : 1 oz. cb 75 Uiubt Copal Varnish, see VARNISH COPAL...........0 0.0. c ce ee ne Copper Metal; Mol 2002010 nea. seco ieee eee. Fee0 eS bagheeineave 1 oz. paper -10 Uiulz 4 oz. paper .36 Uiunu 1lb. paper 1.20 Uiuqo 5 @PANUIAT, 24a ean aap dee eee Baker Analyzed 1 lb. cb 17 Uiuxa 5 Ib. eb 3.20 Uivdo 10 lb. can 5.90 Uivgi 20 lb. can 13.75 Uivie ei ie Sheet, .008 in. Electrolytic........ Baker Analyzed : 1 oz. paper 10 Uivsj 4 oz. paper .35 Uivuf 1lb. paper 1.05 Uioyx 5 lb. paper 5.00 Uiwel oe ae Granulated! Shot... 05 .40)c4 08 Baker & Adamson 1 Ib. etn .69 Uixek Fu x Turnings, Short.................. Baker & Adamson 1 lb. ctn .67 Uixmu 5 lb. ctn 2.95 Uixop : ep eee a Toa een ty aid lee dle egal aire rae ean oente naa Merck Blue Label 4 oz. cb 45 Uiyej 1 lb. eb 1.25 Uiyhd “Acetate, c. p., crystals (Cupric).......... Baker Analyzed 1 oz. cb 17 Uiypm 4 oz. cb 45 Uiysg 1 lb. cb 1.26 Uiyue ne ss Gig Dis tenes lope ater Ay metered ue Baker & Adamson 1 lb. cb 1.52 Uizetr a FE Ale ieth Barna GM mat Ds ia aeeat, Brae & Merck Blue Label 1 oz. eb .25 Uizms 8 oz. cb 1.00 Uizon ‘““ Aceto Arsenite, c. p., powder............. Baker Analyzed 1 oz. cb 33 Ujadh 4 oz. cb 1.01 Ujafd 1 lb. eb 3.14 Ujahz “Ammonium Chloride, c. p. crystals (Cupric) Baker Analyzed 4 oz. cb .30 Ujanm 1 lb. eb 15 Ujapi ie ty Cp Baker & Adamson 1 oz. cb 22 Ujayq 1 lb. eb .69 Ujbam ay ee See UR en a Near ween ceo Merck Blue Label 4 oz. gb -60 Ujcal 1 lb. gb 1.75 Ujeiv oe ms Sulfate, c. p., crystals (Cupric). Baker Analyzed 4 oz. cb .29 Ujdde 1 lb. eb .74 Ujdfa o : ne TGINDERe ee aes eee ae Baker & Adamson 4 oz. cb 22 Ujduv 1 |b. eb .66 Ujeaj ““ Arsenate, c. p., powder (Cupric).......... Baker Analyzed 1 oz. eb .30 Ujehv ‘Arsenite, c. p. (Cupric).................. Baker Analyzed 1 oz. eb 23 Ujeni ‘“ Borate, c. p., powder (Cupric)............ Baker Analyzed 4 oz. cb -75 Ujewq 1 lb. eb 2.27 Ujeym “Bromide, c. p., (Cupric)................. Baker & Adamson 1 oz. eb 41 Ujfis rs a C.ps (Cuprous))s4-naneoe ene aes Baker Analyzed 1 oz. cb .23 Ujfyl 4 oz. eb -66 Ujgez 1 lb. cb 1.96 Ujgoe Carbonate, c. p., powder, basic (Cupric)... Baker Analyzed 1 oz. eb 17 Ujhda 4 oz. cb .45 Ujhgu 1 lb. cb 1.26 Ujhjo 5 lb. cb 5.65 Ujhlk ORIGINAL PACKAGES—Our packages are those adopted by the various manufacturers whose goods we list. No attempt has been made to follow either the avoirdupois or metric system. Metric specification for items listed and packed by avoirdupois weight, and vice versa, prevents the use of stock on hand and involves special factory packing in order to secure the protection of the manufac- turer’s label, all of which tends toward delay and increased cost. the universal adoption of the metric system so much desired by many scientists. ric packing wherever practicable, but in trades where avoirdupois packing has been long established, the change can not be made rapidly. Prompt, accurate and economical service is much facilitated by the use of original package quantities as listed, or even multiples thereof, in the preparation of order and quotation lists. It also retards, rather than furthers, We encourage met- 82 A R T H U R H. T H O M A 8 Cc O M P A N _ Y Item Maker or Brand Size pkg. Price Code Word Copper Carbonate, c.p..................... Baker & Adamson 4 oz. cb 36 Ujhur 1 lb. eb 1.23 Ujiaf 5 lb. cb 5.85 Ujieb “Chloride, c. p., crystals (Cupric).... Baker Analyzed 4 oz. cb .30 Ujijn 1 Ib. eb 17 (Ujil 5 lb. ecb 3.25 Ujine as Cc De (CupTrie)is.ac ac tgecenrnene oe Baker & Adamson 4 oz. cb .29 Ujiug 1 lb. eb .94 Ujyiwm 5 lb. cb 4.40 Ujizg cS p., powder (Copper Mono Chloride) (Cuprous)............ Baker Analyzed 1 oz. cb 18 Ujjio 4 oz. cb AT Ujjnd 5 lb. cb 5.95 Ujjrv 10 lb. cb 11.50 Ujjtr 25 lb. crock 26.50 Ujjen 50 lb. crock 51.00 Ujkad cs ‘“ e. p., anhydrous, powder (Cupric) Baker Analyzed 4 oz. cb .40 Ujkuo 1 lb. cb 1.09 Ujlac a os CG WUTC eed lee satu ron ea Merck Blue Label 1 oz. eb .20 Ujloz : 8 oz. cb 50 Ujlyf a a (Cuprous).................... Merck Blue Label 1 oz. eb .25 Ujmwi 4 oz. eb .70 Ujnby 8 oz. cb 1.25 Ujnes 1 lb. eb 2.25 Ujnik tS SERV ORAtes iC. Do. cie.ton o. soe deo aoe coat Baker & Adamson 4 oz. cb 47 Ujnyd 1 lb. cb 1.66 Ujoaz Or “Wactates cia kon oie. oohuu- eee aca a ah pee Pfanstiehl 1 oz. cb 1.00 Ujogn 1 lb. eb 12.006 Ujou “‘ Nitrate, pure crystals. . Shea Merck White Label 1 lb. cb -70 Ujopu ce “ ¢@. p., erystals (Cupric), seen eee le Baker Analyzed 1 oz. eb 14 Ujowg 2 4 oz. eb 31 Ujoyc 1 lb. eb .80 Ujpay 5 lb. cb 3.40 Ujpeq 10 lb. cb 6.30 Ujple t= GHD doetee a eo Sas een ete eee cats Baker & Adamson 4 oz. cb .24 Ujqax 1 lb. eb 75 Ujqlb “Oxalate, c. p., powder (Cupric)........... Baker Analyzed 1 oz. cb 26 Ujrhi 4 oz. cb 17 Ujrot 1 lb. eb 2.35 Ujryz “Oxide, c. p., black powder (Cupric)....... Baker Analyzed 1 oz. cb 17 Ujsug 4 oz. cb -43 Ujtem 1 lb. eb 1.17 Ujtie 5 lb. eb 5.30 Ujtly 10 lb. eb 10.20 Ujtrl “ ““ @. p., black coarse (Cupric)........ Baker Analyzed 1 oz. eb 17 Ujudn 4 oz. cb -45 Ujuhf 1 lb. eb 1.24 Ujujb 5 lb. cb 5.65 Ujulx 10 lb. cb 10.80 Ujuns es $C Die WATE y foto ye Lee dy So ann oaths Baker Analyzed 1 oz. 17 Ujuve 4 oz. -45 Ujuxcy 1 |b. 1.24 Ujvas es es der (Cuprous)....... Baker Anlayzed 1 oz. eb 21 Ujvop By red powder (Cay ) 4 oz. cb -48 Ujvyv 1 lb. cb 1.68 Ujwej es FE Sopa Man cuiun. a ieccne enh ee eee Merck Blue Label 4 oz. cb 60 Ujxaq BEB plas 1 Ib. eb 2.25 Ujxon ‘ UG LET fice ais il ph ove vets ao a Merck Blue Label 4 oz. cb 55 Ujydj Dowden seg aets 1 lb. cb 1.80 Ujyhb ee EOS AMAL Oo vie gnae sy alg secish tins Made ate es Merck Blue Label 4 oz. eb 70 Ujyom ee 1 lb. cb 2.25 Ujyqi ‘Phosphate, c. p., powder (Cupric)........ Baker Analyzed 1 oz. eb .23 Ujyzq “Potassium Chloride, c. p, crystals (Cupric) Baker Analyzed ‘ = an oe ae 5 lb. eb 3.55 Ukab) “ . i ls (Cupric). Baker Analyzed 1 oz. cb 7 Ukahx Potassium Sulfate, c. p., crystals (Cup ) 4 oz. cb 45 Ukajt 1 lb. cb 1.26 Ukalp 5 lb. cb 5.70 Ukank i GUpri@)” depsiend Hae 1]b. ctn 18 Ukavu Sulfate, coml. crystals (Blue Stone) (Cupric) Bib. box .68 Ukarg 25 lb. pkg. 2.50 Ukazm 100 lb. pkg 9.00 Ukbbi 33 A R T H U_ R H. T H O M A S Cc 0 M P A N ¥ Item Maker or Brand Size pkg. Price Code Word Copper Sulfate, U.S. P., erystals................ Merck White Label 1 lb. eb -40 Ukbuv © 5 lb. cb 1.55 Ukcaj se “ U.S. P., powder................ Merck White Label 1 lb. eb 42 Ukcra 5 lb. cb 1.65 Ukdai a “ e@. p., crystals, fine (Cupric)....... Baker Analyzed 4 oz. cb .26 Ukdut 1 lb. eb .62 Ukeah 5 lb. cb 2.55 Ukecd 10 Ib. cb 4.70 Ukeez a “ @. p., erystals, large (Cupric)...... Baker Analyzed 4 oz. cb -26 Ukemj 1 lb. cb 62 Ukepe 5 lb. cb 2.55 Ukery 10 lb. eb 4.70 Ukeus 25 lb. keg 10.50 Ukewo 50 lb. keg 20.00 Ukeyk ms Pe ak the A Rar es Sak yeah te Merck Blue Label 4 oz. cb .35 Ukfod : 1 lb. eb 1.00 Ukfyj 5 lb. cb 4.50 Ukgex “ ¢@. p., erystals, large (Cupric)...... Baker Special 4 oz. cb 34 Ukhea 1 lb. cb 91 Ukhew 5 lb. cb 3.95 Ukhio = ““@. p., anhydrous, powder (Cupric) Baker Analyzed 1 oz. cb 16 Ukhtr 4 oz. cb .38 Ukiad 1 lb. cb 1.05 Ukiev Be “e.p., anhydrous................ Baker & Adamson 4 oz. cb 32 Ukith 1 lb. eb 1.05 Ukine Sulfide, c. p., (precipitated) powder....... Baker Analyzed 1 oz. cb 22 Ukiyg 4 oz. cb 62 Ukjac 1 lb. eb 1.83 Ukjho “ Tartrate. c. p., powder.................. Baker Analyzed 1 oz. cb .30 Ukkab Copperas, see FERROUS SULFATE............0 0 eee ccc ce ce eee Coralline;see: A CLD ROSOLI Gasxic ck eceaehaed ade eeeeeee eet Bebe Vibe: Corn Sugar;:see DEXTROSE. nei eile ees Monee heneeietGeee Apnekee 2 at4 Corrosive Sublimate, see MERCURY CHLORIDE ...................00 eee cee Cotton Absorbent. oie tee na anunties, cAemiiee sac etmeet es 1 lb. etn -60 Ukkmd 50x1 Ib. case 27.50 Ukkoy S INioneA bsorbentt ss o.625 noe teat hediem awe, -dedeiaOeh ees bate eee ee 1 Ib. etn .65 Ukkwi “Wool, Usual com’! quality as used for plugging test tubes: uc.Gacaeciudidcns oh chil ocdeeetet oath ee 1 lb. pkg Al Uklgo 50x1 Ib. pkg 18.00 Uklik Cream of Tartar, see POTASSIUM BITARTRATE ...............2.5.00 see eee Creatine nie ets ek nate ah a oe eo ee Pfanstiehl 1 gram gv 3.70 Uklyd ee Standard Solution, see SOLUTION GORA ENGBI A tery ters an acd eae weed cece cn ey ceo eee: Creatinine, from Urine.....................0-.. Pfanstiehl lgram gv 4.50 Ukmmb ae Zinc Chloride....................... Pfanstiehl lgram gv 3.20 Ukmyc Gre Oli «se Ea Pearson’s 1 |b. cb 1.00 Uknhk Creosote, U. S. P., IX. A mixture of Phenols and Phenol derivatives, chiefly Guaiacol and Creosol, obtained during the distillation Of WoOd=baR wae sitsascect inh d Guesaun Mae Merck White Label 1 oz. cb 17 Uknyb 4 oz. cb 34 Ukobv 1 lb. eb 87 Ukodr c= Brom. Beechwood) WiiSs'P ieee tees Date Seale led 1 lb. eb 3.50 Ukojf Crésoly Us SeP cinch soa ne teerentien sagem dies Merck White Label 1 lb. eb 43 Ukoro “ Phthalein, '!pH range 8.2-9.8, Standardized dry powder........ Hynson, Westcott & Dunning ys gram cb 25 Ukoya 0 1 gram cb -70 Ukpaw “Red, 'pH range 7.2-8.8 (o-Cresolsulphone- phthalein) Standardized dry powder Hynson, Westdott & Dunning zo gram cb 25 Ukprn ; : lgramcb 2.00 Ukpyz ee “10.04% aqueous Standardized Indi- cator Solution..................... La Motte 10 ml. plain ampoule 50 Ukrau 10 ml. tubul. ampoule -60 Ukrie 500 ml. gb 3.10 Ukruf Gresy Echt Violétaicc7 2cG dG hcn aenote oneeidsus Coleman & Bell 10 gram gv 11.00 Uksoq 25 gram gv 2.25 Ukssi Crystal Violets c2 ssc wkouein yy tienes Coleman & Bell 10 gram gv 80 Uktek , 25 gram gv 1.75 Ukthe Cubes, Chlorine,seeCALCIUM HYPOCHLORITE .................2..00 cece eee 1Clark and Lubs Indicator. See Clark, ‘‘The Determination of Hydrogen-ions,’’ Baltimore, 1920, also a more complete discussion under “Colorimetric Apparatus” on pages 163 and 164 of the Apparatus section of this catalogue, and a special group listing on page 102 of the Reagent section. 34 A R T H U R H. T H O M AS Cc O M P A N _ Y Item Maker or Brand Size pkg. Price Code Word Cubes, Oxygen, for generating Oxygen,seeOXONE ....... ee ‘« Sulfide, for generating Sulfuretted Hydrogen see SULEIDE, CUBESx Aria e, Heettiaeer amen BaD Sada ‘Sulfite, for generating Sulfurous Acid, see SUGELPE CUBS ein iu er bers Ma nee kc taraay fa eatitteariiy enable Cumarin Ne eae clone hakn a ater or ade Merck White Label 1 oz. cb 52 Ukuar Cupels; Bone Ash: for;.see- BONE ASH. vce cee. eheadeecka eee AEG eRe © Sel Gupferron ©, Snsebcar tees eta Se Be Pfanstiehl 1 oz. cb 2.75 Ukuhd Curcumin, see TUMERIC. BAe pier aye Aaa VN Meda ot ante ate neta RE) rie AT Ca Cyanide Chloride Carbonate Mixture, antler: for Case hardening sea ciennnetnak re tesatecadaans Gat ginh kane neuah a ueeneres 1 lb. can 47 Ukupm 5 lb. can 2.20 Ukusg “Chloride Mixture, 73-76% fused technical (not an Insecticide).... 2.0.0... eee 1 lb. can 51 Ukuzs 5 lb. can 2.40 Ukvbo Be ‘© equivalent in strength to 98-99% Potassium Cyanide: 20 2cesa cs Baker Analyzed 4 oz. cb 33 Ukvyt 1 lb. eb .86 Ukweh 5 lb. cb 3.65 Ukwom Cymene, steam distilled................... kee SR awn 1 lb. eb -50 Ukzfe 1 gal. cb 2.50 Ukaiy Cysteine............ Beiagis Go oticd eas DE Re Sake .. Pfanstiehl lgramcb 2.00 Ukext 10 gram cb 15.00 Ukxzp os Hydrochloride........................ Pfanstiehl 1 gram cb -90 Ukyfd 10 gramcb 6.00 Ukyhz CY SUIT Coes es eject esc rey See EI Pfanstiehl 1 gram cb 75 Ukynm 10 gram cb 5.00 Ukypi d-Levulose from Invert Sugar, see LEVULOSE.... «1... eee Ma Ria GF ps ie eel Hawn my tad as Coleman & Bell 10 gram gv .75 Ukyyq 25 gram gv_—si1..60 Ukzam Damar Xylol, see BALSAM DAMAR IN XYLOL ...........-.--55550 eee ee Decolorizing Carbon, see CARBON DECOLOR- ZLIN Cote oon i ek eke easement segs See temee pean haugtale, iets Dehydrated Culture Media, see under separatename ...........-------) tees deKhotinsky Cement,seeCEMENT.............0 0 2s eee eee eee ‘Dental Dam, see RUBBER TISSUE............ 0 0 eee eee Devarda’s Alloy, see METAL DEVARDA’S...... 0 0.0... eee eee eee eee - Dextrine, white com’)... 2.66... eee 4 oz. ctn 14 Ukard 1 lb. ctn 41 Ukzyp 5 lb. etn 1.75 Ulaaj 2 yellow; com’! 25. o7245 Posen dansnewete HO areas 1 |b. ctn 23 Ulahv 5 lb. ctn .90 Ulajr 100 lb. etn 13.00 Ulaln y H. P., “c. p.”, precipitated by Alcohol... Merck White Label 1 oz. cb .30 Ulasy 4 oz. cb .90 Ulawq 1 lb. eb 2.75 Ulaym Dextrofructose, see LEVULOSE..... 2.0... 0.655 0 cece eee eee tne bees Dextrogalactose, see GALACTOSE..........-50. eee e recent eee es eet eee tes Dextroglucose, see DEXTROSE . Opppae GUERRA RSG BRERA coerce d : for Caen Sac ar 1 lb. ctn 16 Ulbhu Dextrose, pure, anhydrous, granu ( g S aa cy Se ik 25 lb. pkg 2.00 Ulomk es i Ss Hee pOep Ae me coNeme ss, Geen ayant ensure a eens 1 lb. ctn 15 Ulbyl ee nae eee 5 Ib. box 50 Uleez 10 lb. paper 70 Uleir “ “ElWeose) DUPE: aise Si ee see Merck White Label 1 oz. cb -20 Ulewo iGinetee Dane as 4 oz. cb “42 Uleyk 1 lb. cb 1.20 Uldag ie Auli eee “Dileo 4 oz. cb 95 Uldjo Bache se Bacon 8oz.ch 1.90 Uldik 1 lb. eb 3.60 Uldnf cs _o oe. ......... Pfanstiehl 1 oz. cb 35 Uleaf (Glucose) anhydrous... - 4 oz. cb 1.10 Ulecb 1 lb. cb 3.75 Uleex NE ageesey sy Aan cecell aiStiua Baro Be ike RE Baker Analyzed 4 oz. cb 83 Ulekl op ee ee 1 Ib. eb 2.52 Ulemh 5 Ib. cb 11.70 Uleoc 10 lb. cb 22.50 Uleqy US VARS EGE. aha pa ted wanes woes io ess Difco 4 oz, cb 2.05 Ulexk Broth, dehydrated.......--- i ib ob 735 Ulezg A R T H U R H. T H OM A S Cc oO M P A N Y Item Maker or Brand Size pkg. Price Code Word Dextrose, Hydrate (Glucose) ................... Pfanstiehl 1 oz. eb .30 Ul fio 1 lb. eb 1.35 Ulfli syrupy (Glucosum)................... Pfanstiehl 1 Ib. cb 1.25 Ulftr Diabetiny'seesGR VUEOS Bid chick Vesa GeO AAAs. “Ghiaiieante "-aeiok Diamidoazobenzene Hydrochloride, see CHRY- SO TDOENH ss hee tes, Sreua ENR) | eesoa ame ain ener Diaminodiphenyl, se BENZIDINE.............0 0... es Diamond Green G, see BRILLIANT GREEN.... ................... Ink, for writing on glass see INK. ...... 0 ee Dianil Red;:see‘CONGO RED? .3 soe see ees: SEGRE 0 | ee See Diastase of Malt (Maltine) U.S. P., medicinal.... Merck White Label 1 oz. cb .35 Ulgmf 4 oz. cb 1.20 Ulgoa 1 lb. cb 3.75 Ulgru Diatomaceous Earth, se KIESELGUHR........ 0 1... ne Direthylamines. 2.3.92: sva. oes HO eee eae een cesee Pfanstiehl 1 oz. cb 1.30 Ulhba 1 lb. eb 16.00 Ulheu b-Diethylaminoethyl Alcohol, see ALCOHOL b-DER THY GAMIENOB BY Ls 2200 .scNel ease aetarieas Azur; tabletss.f 2: aecoenat Ae ate sys ea Soloid tube 6 tablets .80 Umatu “Methylene Blue...........---.----+55-5 Coleman & Bell 10 gram gv 11.75 Umazi “a as “Agar dehydrated......... Difco 4 oz. cb 2.05 Umbhs 1 lb. cb 7.25 Umbjo Epsom Salts, see MAGNESIUM SULFATE...... 0 2. -- 20-2 sees e ee eees eee ees PitO Moo ee ee Si RE Ses a ees Pfanstiehl 10 gram gv 3.60 Umbrx a 25 gram gv 9.00 Umbur PINE ink cel as ke ae EN PES oe ea ara gces Coleman & Bell 10 gram gv—si1..10 Umbyj Erythrosine 25 gram gv 2.50 Umcaf Eschka’s Mixture, see MAGNESIUM OXIDE AND SODIUM CARBONATE ........--.-5005005 tee tee _ Ether, Sulfuric, U.S. P., concentrated. Notintended for anaesthesia. Contains about 4% lGGWOl cca wee tee GRR Ee ee eS 4 oz. tin .20 Umehr paper 1 Ib. tin ‘AT Unmelj 5 1 tin 1.95 Umene 25 1b. drum 7.75 { anan extra Eoot Umepa 50 lb. drum 14.00 { drum extra 10.00; Umesu 300 lb. drum 69.00 { drum extra 30-00} Umerk “3 ee Ws Se Ries ore tts eh pean Baker Analyzed 1 lb. cb 65 Umdfu : 5 lb. cb 2.38 Umdio “ i P.. for anesthesia. Contains : eee Ce 302 Aleohol Ries emit ama are ena aanc nay 4 oz. tin -20 Umdir 1 |b. tin 50 Umdyh 5 lb. tin 2.10 Umead “ “s IA te ete sens Squibb 4 oz. tin 31 Umehp for anmesthesia - 8 oz. tin 55 Umejl 1 |b. tin .95 Umemf 1 kilo 2.05 Umepy Ay Re 2 chy Ue oR His T H O M A 5 Cc O M P A N Y Item Maker or Brand Size pkg. Price Code Word Ether, Sulfuric, washed, contains about 134% AI CONOl is. 5.nk So tenicsdacndckactiow ecdls dqvadaeeles. a aan 1 lb. tin -67 Umeze 5 Ib. tin 2.95 Umfba 5 lb. can 4.03 Umfrt i WASHEG: cc pen eeccius ween aee pen etORE A Baker Analyzed 1 Ib. cb -98 Umfme a 2x5 Ib. can 7.86 Umfun “a ce. p., distilled over Sodium (Anhydrous WW GHEE in. Gt. lak Mee tce sh astern aeons Baker Analyzed 1 Ib. can 1.21 Umgna 5 lb. can 5.08 Umgqu 2x5 lb. can 9.96 Umgum “distilled over Sodium, anhydrous.......... Merck Blue Label 1 lb. cb 1.50 Umhdu oP ASD. PTs OA Ua Disc xaos kid me eiaks dure eae Bake tellers Merck Blue Label 1 lb. eb 75 Umhle “Acetic, U. S. P., VIII 90% (Ethyl Acetate) ................0.-. 1 lb. cb 57 Umhyd “ “* e. p., absolute (Ethyl Acetate)...... Baker Analyzed 1 lb. cb 1.44 Umier 5 lb. cb 6.55 Umign ‘ “¢e. p., anhydrous 99.7% to 100% (Ethyl Acetate). .ccic incon ete Pfanstiehl 1 |b. eb 15 Umimb ‘“ Hydriodic, see ETHYLIODIDE......... 0 .................. be = cee atts ‘“ Hydrobromic, see ETHYL BROMIDE.... ..............2625066600 ve eee “ Oenanthic (Oil of Cognac)............... Pfanstiehl 1 oz. cb 35 Umiso 1 lb. cb 4.00 Umiuk SS “Pellargonies cise aye cee wean aes Pfanstiehl 1 oz. cb 6.50 Umjay “~ Petroleum, B. P. 40-60° C, F. O. B. Phillips- burg, N. J. Express shipment limited to 50x1 lb. cans or 1x5 WbicCancs- oes Aes taa tae Baker Analyzed 1 lb. can 56 Umjle 5 lb. can 1.98 Umjnx 2x5 lb. can 3.76 Umjrp 5x5 lb. can 9.15 Umjyb a oe B. P. 25-40°C, F. O. B. Phillips- burg, N. J. Express shipment limited to 50x1 lb. cans or 1x5 |b. CAN eta susjals eae meen e tee eines Baker Special 1 lb. can .88 Umkou 5 lb. can 3.43 Umkui 2x5 lb. can 6.56 Umkzxe 5x5 Ib. can 16.15 Umkzy Ethyl Acetate, see ETHER ACETIC............0 2.2 e cee ee eee Acetoacetate, refined.......... Coates Pfanstiehl 1 lb. cb 7.50 Umimy £6 BEN ZOAtO ws Ackcon vno.8 Ae tdid honk d Rene aurae Pfanstiehl 1 lb. cb 2.75 Ummos “ Benzyl Aniline, c. p... 2... .-- 2. eee eee Pfanstiehl 1 lb. eb 5.25 Ummau “Bromide, H. P. “c. p.”, (Ether Hydrobromic) Merck White Label 1 lb. gb 2.85 Ummve £6 MeBUtyTate:sio.o0 35 noo eee oe eas Pfanstiehl 1 Ib. cb 2.80 Umnth © “Formate: .c0s jun gciaapes ee che ere ae Pfanstiehl 1 oz. cb -30 Umocp 1 lb. cb 2.10 Umoel “ Iodide (Ether Hydriodic)...............5. 0 chee eee eee eee eee 1 oz. tube 57 Umokz 1 lb. gb 7.75 Umomv ©. ‘Proplonate 0.5208 cates eye ates Laan Pfanstiehl 1 oz. cb .80 Umosi 1 lb. eb 8.25 Umowa HS Valeri at Gieccccads via ¢ vttehtegSe et incsoeuas een eae Pfanstiehl 1 Ib. eb 7.50 Umpfi Ethylene Bromide... ....... 2.500.060 ee ce cece eee renee eee eee 1 oz. ev -30 Umpop 1 lb. cb 3.12 Umpsh Burparal ois 26.2 cpa Paice AS REET) Peres ERE Sas 100 gram cb_.80 Umalv FES NNT piieat 3 Gs io UE cei thes eM he Mey an UU rahe eirtonal tra eiatia rn 100 gram cb_ .90 Umria Parrant’ Ss: meqdiin: 2 soi: sch cated sbeyp ec oeeene naan dae hee 25 ml. gb 75 Umsiz Fehling’s Solutions, see SOLUTIONS. ...........0 20sec cece cee eee Feldspar,; Powder: c.s.500. igicustie eee Aerees. rie akeie owiehe s 1 Ib. etn 17 Umtao 5 lb. etn .60 Umteg Ferric Alum, see IRON AMMONIUM SULFATE (BERRIC)asccuiiewecceerencesen Death oriteiee st eauge Fibrin, from Blood............------ 00+ see sees Merck White Label 1 oz. cb 75 Umtol 4 oz. cb 2.55 Umtsd 1 lb. cb 9.90 Umtyr Fire Clay; powders... 20.02.06 .2¢0¢S4:4Reieeedss Se ebsptevanee eens 1 Ib. etn 16 Umufd 5 lb. etn 50 Umuhz 100 lb. ctn 3.00 Umujv Fluorchrome, see CHROMIUM FLUORIDE..... ....... ee eee eee ee eee Fluorescein (Sodium Salt) water soluble.......... Coleman & Bell 10 gram gv 75 Umupi 25 gram gv_—s:11.60 Umusc Fluorspar, Powder, see CALCIUM FLUORIDE..............-.-020255 eee eee A R T H U R He “WT oor “Oo (Me -A- OS: © 70." (M: “PR A Ne UY Item Maker or Brand Size pkg. Price Code Word Formaldehyde, Solution 40% U.S. P.....0.0.000.0 ee 1 Ib. eb .36 Umvam 5 lb. cb 1.35 Umoga 9 1 cb ‘ 2.25 Umviw 100 lb. carboy 20.00 { carboy extra B00; Umomo 400 lb. bbl 72.00 Umvoj é Solution 35-40°% (Formic Aldehyde) Baker Analyzed 1 lb. eb 59 Umwed 5 lb. eb 2.40 Umwoi oY Neutral 80064 2642 ieee Merck Blue Label 4 oz. eb .30 Umzec 1 lb. cb 75 Umagy as Para; see TRIOXY METHYLENE? sc.ce320eiesi.iSee Garciede “anus POrm aint) Fishers Ge es Sas ut, nee oie ee eee Schering 1 lb. eb 45 Umaxyn Formic Aldehyde, see FORMALDEHYDE SOLU- TION 40 Goes ween ace, Het ee eaten A pee cy Formin, see HEXAMETHYLENAMINE........ ..........0..0.000020 he ee Formol, see FORMALDEHYDE SOLUTION 40% ................ By, SCs cel Bagi: Fructosé;ssce LE VU LOS Di ties otc Seti dote hare Bieta ieantuces Fruit; Sugar-see: LE VU LOSER = ache wranrawuiatins Goitamensaeeta conan _chespbaiints Sdncas Fachsin;. Acidh: 2.6 6.5 oohu pts an BO hatha Coleman & Bell 10 gram gv 75 Umygx 25 gram gv 1.60 Umyit 100 gram gv_—— 5.60 Umykp 200 gram gv 99.60 Umyml Basic, pure crystals.................... Coleman & Bell 10 gram gv 75 Umysy 25 gram gv_=_:1.60 Umywq 100 gram gv_— 55.60 Umyym 200 gram gv 9.60 Umzai “pure, 0.1 gram tablets............ Soloid tube 6 tablets .35 Umzko ff KSs see PUCHSIN AGI Di nook As edt Oy, Geese these ese aieaeeie. cheese Buller’ s:Barth Re a oA Gs VR H. TT H O M A S CO M P A N Y Item Maker or Brand Size pkg. Price Code Word Mercury;.distilled,technical..) 3.203. occc4ksceceess 28s ee ieadees Pees 1 lb. jug 1.12 Uweec 5 lb. jug 5.00 Uwcegy 25 |b. jug 22.00 Uwenj a WeSs.Py redistilled purified sc: cuuaivwes. —Sesdeeneaes tacos es 4 oz. cb .40 Uweal 1 lb. jug 1.34 Uwdeb 5 lb. jug 6.10 Uwdit 25 lb. jug 27.50 Uwdml PD Listes ey Sitch ch Rips ASS AUR OC ert Eat na Merck Blue Label 4 oz. gb -65 Uwdxo 1 lb. gb 2.25 Uwdzk oe specially purified for use with calomel electrodes. . . ln Seine Res snes eecUm eet Rate surg Min oath ea Ante 1 Ib. cb 2.50 Uwebg a Acetate, c. p., (Mercuric).............. Baker Analyzed 1 oz. cb .33 Uwefy 4 oz. cb 1.00 Uweis 1 Ib. cb 3.14 Uweko _ Bromide, c. p., crystals (Mercuric)...... Baker Analyzed 1 oz. cb -60 Uweut a “e@. p., (Mercuric)............. Baker & Adamson 1 oz. cb 64 Uwfez e “ (Mercuric)................... Merck Blue Label 1 oz. cb 1.00 Uwftu : 4 oz. cb 3.50 Uwfus < Chloride, U. S. P., crystals (Corrosive Sublimate) (Mercuric) (Bichlor- TO) eaten eee aren tee Merck White Label 4 oz. box .36 Uwfwo 1 lb. box 1.20 Uwfet 5 lb. box 5.80 Uwgbe * “U.S. P., powder (Mercuric)... Merck White Label 1 oz. eb 13 Uwglk 4 oz. box .30 Uwgnf 1 lb. box 1.00 Uwgur 5 lb. box 4.80 Uwgyj s “« @. p., powder (Mercuric)...... Baker Analyzed 1 oz. eb 21 Uwhpa 4 oz. cb 56 Uwhvo 1 lb. eb 1.64 Uwhzg 5 lb. cb 7.50 Uwica 10 lb. cb 14.20 Uwifu 5x5 lb. cb 35.25 Uwihq a “@. p., erystals, (Mercuric)..... Baker & Adamson 4 oz. cb 55 Uwipz 1 lb. cb 2.00 Uwjjl 5 lb. cb 9.70 Uwjuo ae ff INV ORCUTIO)G seks chuc tole a taritea cece Merck Blue Label 1 oz. cb 35 Uwitr 8 oz. cb 1.50 Uwjev se Ae SU Ss Bey Bower (Oren) (Mercurous) . : . Merck White Label 1 oz. box ll Uwkim 4 oz. box 36 Uwklg 1 lb. box 1.21 Uwknb se ““ @. p., powder, (Mercurous).... Baker Analyzed 1 oz. eb 19 Uwkzd 4 oz. cb 55 Uvwlet 1 lb. eb 1.68 Uwlmd 5 lb. cb 7.80 Uwloy 10 lb. eb 14.80 Uulrs a «« ¢@. p., (Mercurous)........... Baker & Adamson 1 oz. cb 17 Uwlxg 4 oz. cb 59 Uwlze 1 lb. eb 2.17 Uwmdu os “Electrolytic, specially prepared for use in Calomel Cells (Mer- CULOUS) eae iechece ce ere ee La Motte loz. Uwmle 4 oz. Uwmox “ Cyanide, c. p., powder (Mercuric)...... Baker Analyzed 1 oz. eb 45 Uwnaz S °¢@. py (Mercurie). cg s2de sees Baker & Adamson 1 oz. cb 51 Uwnjh u Iodide, U. S. P., red, powder TONY Biniodide) (Mercuric) . Merck White Label 4 oz. cb 1.28 Uwnrq 1 lb. cb 4.43 Uwnim ss “ @. p., red powder (Mercuric)..... Baker Analyzed 1 oz. cb 47 Uwoay : 4 oz. cb 1.52 Uwods es “ —e. p., red (Mercuric)........... Baker & Adamson 1 oz. cb -94 Uwoke 4 oz. cb 3.66 Uwoma ce “ ved... 0. ..........4.......... Merck Blue Label 1 oz. cb 65> - Uwosn 4 oz. cb 1.50 Uwouj ns Nitrate, c. p., crystals (Mercuric)....... Baker Analyzed 1 oz. gb -28 Uwpep 4 oz. gb 73 Uwplb 1 lb. gb 2.01 Uwpps 5 lb. cb 8.80 Uwpsm 10 lb. gb 16.70 Uwpwe of «e. p., (Mercuric).............. Baker & Adamson 4 oz. gb -62 Uwgqeo 1 lb. gb 2.29 Uwgig 52 A RK T HH U OR H. 8 Oe MO As - 1 qt. eb 80 Uzpib 1 gal. can 2.20 Uzpnq C6 is Ra Hoilad aaa deen eeehre tie ORE Eye PRO 1 pt. cb 45 Uzpwy Linseed, boiled... ...------- 1 gal. can 1.80 Uzqaq “ CE Ne or ee Si el a ee ed henge acon ha cehiee art SAN gm 1 pt. eb -40 Uzqon De a Soca a irae 1 gal. can 1.70 Uzqyt es hanevabe NIT ROBENZOL ..ti cee: RAreReeR eee | REE Bees ‘ Ne Pere ere ee oe heen eee eed eee a 1 pt. cb 1.40 Uzerys oY DOU 6 toy, cea sg eerie nee aay PU NS 1 qt. cb 2.45 Uzsdi Reena eee ths 1 oz. cb 55 Uzsls “ Origanum, Cretici......-0--. 022 seer te cn 180 oak 1 lb. eb 6.30 Uesyr A R T H U R Hs, Pf (H) sO MA: 3S Cc O M P A N Y Item Maker or Brand Size pkg. Price Code Word Oil, Paraffin, white; pure... c.2c2avsaeaer einen Ada taehcwacs oui 1 pt. eb 55 Uztok 1 gal. can 2.50 Uzitre 5 gal.can 10.50 Uetuy Se AS DOL n unas eee gened Na eS aan AAS I law ed cosmetic sehen tele oieiate he 1 pt. cb -84 Uzuci Sho PP Oy PROM rs ck sprains wl, tos os bled eee Baker Analyzed 1 Ib. cb .64 Uzuks << Turpentine; see-TURPENTINE:. 33.6 se00e0. scangdereeieiiedeie Seeeeetn seen “of Vitriol, see ACID SULFURIC. ene oe nee “acaeidkae aes ‘* Wintergreen, synthetic (Methyl Salicylate) (For real Oil Minterercen t see OIL BETULA). .... Merck White Label 4 oz. eb 26 Uzuqf 1 lb. eb 75 Uzusb Orange: 'G: crystals: iic6 es ee eto Ges he Coleman & Bell 10 gram gv .60 Uzuen 25 gram gv_——‘i1.30 Uzved ORCELI 2 S320 re ohne Oe es eee en ee ees Coleman & Bell 10 gram gv——1.00 Uzvuw 25 gram gv =. 2.25 Uzvyo ORCA ors nee a epee eu citeaeoee EEO AT Ae RAP POURS HAVER OUAA SSI. eens testers 10 gram cb 30 Uzwuv 100 gram cb. 2.75 Uzxaj Ortho Tolidine, see TOLIDINE ORTHO........ 0 2... eee ee ee Osmic Anhydride, see ACID OSMIC............ ee cece eee bee nee Osmium Tetroxide, see ACID OSMIC...........0 fee eee ee nee Oxgall, dehydrated... 00.0.0... 0... cece ee Difco 4 oz. cb .85 Uzybg 1 lb. eb 3.10 Uzyde Oxone, for generating Oxygen. . pit oauee aAied cucustenalinn Dia atatedihen’ 2 Ib. can 2.08 Uzyko Oxygen Gas in cylinders, see APPARATUS CATA- TiO Gas Meee ttre t tom pee eee coke cnet naan. SCR, I a Ozokerite, see CERESINE, white and _ yellow (Yellow is only partially purified)......0 2... eee eee ee ee Palladium, black. .c.0. b44¢epee pease wae sleieas Merck Blue Label 5 graincb 2.00 Uzyut 15 graincb 5.00 Uzyxn ae SPONGE pve a id ata a isce nies ava ee Merck Blue Label 5 graincb 2.00 Uzzkn 15 graincb 5.00 Uzzoe fe IG hOrid 624653... ssn ees oe ee en AURA oceans BAe aie eases ote l gram gv 3.00 Uzexm ee Sea Ry ue aan grin ear ares eae Ra es Merck Blue Label 5 grain gb = 1.70 Vaags ; 15 grain gb 4.00 Vaajm Palm Oil Soap, see SOAP PALM OIL...........0 0 fe cee cee eee eee eee be eee Panctreatin,: Ws. 952% acceded Hse Gee atoteeo aah Difco 1 oz. eb -40 Vaast 4 oz. cb 1.35 Vaaup Paper Pulp aoe see APPARATUS CATA- Paraffine Refined 47-49° C (118-120° F.) melting DOMES. es ae conieeetaretacn Ne deear Seaneeaty ns were ea ees 1llb.cake .16 Vabev 10x1 lb. cake 1.50 Vadjl 25x1 lb. cake 3.50 Vabmf 50x1 lb. cake 6.50 Vaboa 100x1 Ib. cake 12.00 Vabru ts “ 50-52° C (128-125° F.) melting DOING Adah ealiontakaaeea times) Caetkatie ena oe etre 1lb. cake .17 Vacac 10x1 lb. cake 1.60 Vaccy 25x1 Ib. cake 3.75 Vacho 50x1 Ib. cake 7.00 Vacki 100x1 lb. cake 13.00 Vacnb ff « 58-55° C. (128-130° F.) melting DOING: 4 Basics orcas cee tera evel! Hye esaes Serene Ges 1lb. cake .18 Vaced 10x1 lb. cake 1.70 Vaddv 25x1 lb. cake 4.00 Vadhn 50x1 Ib. cake 7.50 Vadlf . 100x1 lb. cake 14.00 Vadna Ae “ §6-58° C. (183-135° F.) melting MOINES eenst acco eat eA ene | Canna Olin matin sthy Begeteeg 1lb.cake .23 Vadum 10x1 lb. cake 2.20 Vadzxg 25x1 lb. cake 5.25 Vadze 50x1 Ib. cake 10.00 Vaedu 100x1 lb. cake 19.00 Vaefg Paraformaldehyde, see TRIOXYMETHYLENE.. ............ cc ceeee ee eee eee Paraldehiyde;. U.S os. sag ecg ewes Merck White Label 4 oz. cb 43 Vaeme 1 Ib. eb 1.26 Vaeox Para Nitraniline, see NITRANILINE PARA..... Para Nitro Phenol, see NITRO PHENOL PARA.. Para-Phenylenediamine, see PH EN YLENEDI- MINE PARA Parchment Paper, see APPARATUS CATALOGUE A R T H U _ R H; TT HO M.A Ss Cc O M P A N _ Y Item Maker or Brand Size pkg. Price Code Word Parlodion, A shredded form of the purest, concen- centrated collodion for embedding tissues for section cutting, etc. Now universally used in place of Celloidin............. du Pont 1 oz. cb 1.00 Vaexf Pectin Sugar, see ARABINOSE................. Pectinose, see ARABINOSE................... Pepsin, U.S. P., powder....................... Merck White Label 1 oz. cb 35 0 8©=©6-Vaffp STU 0S ls SCALES se ingest eisecc ace ect eS Merck White Label 1 oz. eb 37 Vafny PEDLOnG |: 45555 cote et ral ele parte de oth nan be DR Armour 25 gram cb 50 Vafuk 100 gram cb 1.65 Vafxe 250 gram cb = 3.90 Vafza 500 gram cbs 7.50 Vagceu * OB ACto oa een Aachen a tigre eer ral N Difco 1 oz. eb 43 Vagma 8 oz. cb 2.45 Vagov 1 lb. eb 4.85 Vagsn Me teh irc aiedet lalate Garde wa ante een talmaree aaaaeyenceia vat Fairchild’s 1 oz. cb -40 Vahbo 4 oz. cb 1.25 Vahdr 8 oz. cb 2.50 Vahfn 1 lb. eb 4.75 Vahhj SO ee eee sti pool wecred as feolas sh SRA eae Uh al RE ae hearth Parke Davis Co. 1 |b. cb 6.00 Vahps 5 lb. can 29.00 Vahsm ee tea paar shee gnats ere aunt ea Witte 250 gramcb = 4.80 Vahya 500 gram cb = 9.50 Vaiaw 1x10 kilo can 180.00 Vaics me Proteose?.. 53.652. 08.0 eon aes eon Difco 1 oz. cb -60 Vaike 8 oz. cb 3.10 Vaimy 1 lb. eb 6.00 Vaiot Permutit,' Folin. A synthetic zeolite powder as used in the colorimetric determination of Ammonia in urine.................... Permutit Co. 1 Ib. eb 2.00 Vaixb Petrohol, see ALCOHOL ISO PROPYL.... 22.0.0 foc ccc ccc bees bees Petrolatum, white (Snow White) ................0 Fee eee 1 lb. can 34 Vajjd 5 lb. can 150 Vajnu =f vellow: (AMbER) savitagee Gane escaue Geeelegaialaeteege 1 lb. can 24 Vajve 5 lb. can 1.00 Vakau Phenacetolin .................... MA ee hes Coleman & Bell 10 gram gv: 11.00 Vakly 25 gram gv 2.25 Vakor Bete ters aa een eee tut Alreata oan Ra toeey aera as Merck Blue Label 2 oz. cb 35 Valat 4 oz. cb 1.00 Valep Phenol; sce ACID CARBOLIG js ait seiheaeein Aiea eee eesleceds aelalns Phenolphthalein,2, pH range 8.4-9.2 (Phenol Phthaleiny: c2%cn sche hone weeeie Hynson, Westcott & Dunning qo gram cb -20 Valid 1 gram eb -70 Valkz es pH range 8.3-10.0.............. Coleman & Bell 25 gram gv 50 8 Valrk te 20.02% aqueous Standardized. . . Indicator Solution.............. La Motte 10 ml. plain ampoule -40 Valzu 10 ml. tubul. ampoule 50 Vambq 500 ml. gb 3.00 Vamdm “ U.S. Poo... 0.2... 222...... Merck White Label 1 oz. tin 22 Vamky 4 oz. cb 78 Vamnr 1 |b. tin 2.39 Vampn EO ett Rds dre cn raaeacnumeca ee ne a aoe Merck Blue Label 1 oz. cb 75 Vanar 4 oz. cb 2.00 Vandl henol Red,2 pH range 6.8-8.4 (Phenosulphone- Sd Paithaleia) Standardized dry powder. Hynson, Westcott & Dunning yo Gram cb 25 Vankz lgramecb 2.00 Vannq # “© 2 0.02% aqueous Standardized Indica- ie go edn secon eypeciad cial wealth costco La Motte 10 ml. plain ampoule -50 Vanva 10 ml. tubul. ampoule -60 Vanyu 500 ml. gb 3.10 Vaoaq 1 See Folin and Bell, “Journal of Biological Chemistry,” Vol. XXIX, No. 2, 1917, ‘‘Application of the New Reagent for the Separation f Ammonia.” : f és A % 2 Clark and Lubs Indicator. See Clark, ‘‘ The Determination of Hydrogen-ions,” Baltimore, 1920, also a more complete discussion un- der “Colorimetric Apparatus” on pages 163 and 164 of the Apparatus section of this catalogue, and a special group listing on page 102 of the Reagent section. 59 As: RY Se SB eR H. 7: Hy O° GMa cA (M. “A> 3S Cc O M P A N Y Item 5 Maker or Brand Size pkg. Price Code Word Potassium Sulfate, c. p., crystals, coarse......... Baker Analyzed 4 oz. cb 32 Voubf 1 lb. eb 84 Voudb 10 lb. eb 6.90 Vougy 25 lb. keg 15.75 Vouir 50 lb. keg 30.00 Voukn . SS es psichystalss sASh, see: SODIUM CARBONATE occu dacce, sauswichedeguegsese “honaiacuhe dice “Lime, see SODIUM CALCIUM HYDRATE .................06.00 eee Sodium Metal, sticks.......................... Merck White Label 1 oz. can 45 Vutig 4 oz. can 59 Vutla 1 lb. can 1.10 Vutno me SEIS LIC KGa ata Rc ote niet Map Meee te ene Merck Blue Label 1 oz. gb .30 Vutyz 4 oz. gb 75 Vuudt “Acetate, U.S. P., granular.............. Merck White Label 4 oz. cb 16 Vuuif 1 lb. cb -40 Vuulz 5 lb. cb 1.65 Vuunu ee me C. ps enystalss o.c44. cc etd aes Baker Analyzed 4 oz. eb 24 8 Vuuti 1 Ib. cb 56 Vuuwe 5 lb. ecb 2.25 Vuvau 10 lb. cb 4.10 Vuvem 25 lb. keg 9.00 Vuvhg 50 Ib. keg 17.50 Vurjc oe “e Ci Decry stalls. cdc ais anc he eee Baker & Adamson 4 oz. cb 19 Vuorl 1 Ib. cb 55 Vuoth 5 lb. cb 2.45 Vurvd oe ee CFYStAIS 2 io hs con he wn eee Se Merck Blue Label 4 oz. gb .30 Vuwdn é 1 lb. gb 75 Vuwgh ve cf technical, fused, in sticks........ Pfanstiehl 1 lb. eb .75 Vuwmo os “ Cx Psp AUSEC Sac cus oucgn Se wert Baker & Adamson 4 oz. cb 30 Vuwsi 1 Ib. cb 1.01 Vuwee a By c. p., anhydrous, fused.......... Baker Analyzed 4 oz. cb .36 Vuxsdm 1 lb. cb -98 Vuxfi “ Alizarin Sulfonate, see ALIZARIN SO- DIUM MONO:SULFONATE.. si:8eeeeseeiceee Gsiwveae tages ‘ “Aluminate;:¢:2piy ohne peed aioe ahs Baker & Adamson 4 oz. cb 19 Vugnr 1 lb. eb 54 Vuxpn “Amalgam, about 2% Na................ Merck Blue Label 1 oz. gb .40 Vuyen 4 oz. gb 1.00 Vuyej ne By Ooeve fies rates Smeaton eeatae et eA Baker Analyzed 1 oz. eb Al Vuylv “Ammonium Phosphate, c. p. crystals (Micro- cosmic Salt) ...... Baker Analyzed 4 oz. cb 32 Vuyte 1 lb. cb -82 Vuyva 5 lb. cb 3.45 Vuzaq 10 Ib. cb 6.40 Vuzem 25 lb. keg 14.75 Vuzge 50 lb. keg 23.00 Vuzia as e CED aaecicisen sia aae Baker & Adamson 4 oz. cb 27) 2) Vuzpl 1 lb. cb .86 Vuzub 5 lb. cb 4.00 Vuzer < es SEE a Sneed eiae a Tre niche Merck Blue Label 4 oz. cb 40 Vyagv 1 lb. cb 1.30 Vyair My Day Paes ee attire eee Baker Analyzed 4 oz. cb .33 Vyaqa ES enaNS Seer 1 Ib. cb 36 Vyatu “ ee Cx Diigee ng Gohan eat Dens epee Baker & Adamson 4 oz. cb .25 Vyazi 1 lb. eb -81 Vybbe a i es DOW GED sculeganarsrenestc Baker Analyzed 4 oz. cb 34 Vybjo ECU pe i 1 Ib. eb "89 Vyblk “6 es Cp hee Aneta eareceaten eta er Baker & Adamson 4 oz. cb 28 Vybur 1 lb. cb 91 Vychr “ Benzoate, U. S. P., powder............-. Merck White Label 1 oz. cb 14 = Vycne : 4 oz. cb 30 =©Vycpa 1 |b. cb 1.00 Vycsu “© Biborate, see SODIUM BORATE........ 0 2... e eee cece eee tne es i SEP powder. dati seen Agen need 1 |b. ctn 16 Vydae Biearnonstes p 5Ib. box 55 Vyddy 25 lb.pke 1.75 Vydfu 112 Ib. keg 5.60 Vydjm “ ‘“ .p. OR a geW son niet Baker Analyzed 4 oz. cb 21 Vydtr Ea i Ib. cb "47 Vydon 5 lb. cb 1.85 Vyead 10 lb. cb 3.30 Vyedx 25 lb. keg 7.00 Vyeft 50 lb. keg 13.50 Vyehp 71 AS Re or ee OU oR H. T H O M A SS Cc O M P A N *¥ Item Maker or Brand Size pkg. Price Code Word Sodium Bicarbonate.......................00005 Merck Blue Label 1 Ib. cb 50 Vyence 5 lb. cb 2.00 Vyeru ‘* Bichromate, (Dichromate).............. Merck White Label 1 lb. eb 35 Vyeze 5 lb. eb 1.45 Vyfba me Me c. p., erystals............00. Baker Analyzed 4 oz. eb 27 Vyfki 1 lb. eb 68 Vyfme 5 lb. cb 2.80 Vyfoz 10 lb. cb 5.20 Vyfsr 25 lb. keg 11.75 Vyufyf 50 lb. keg 22.50 Vygab = c. p., fused, anhydrous....... Baker Analyzed 4 oz. cb 41 Vyglf 1 Ib. eb 1.12 Vygna “ Binoxalate, c. p., crystals............... Baker Analyzed 4 oz. cb 34 Vygum 1 Ib. cb 91 Vygye ‘* Bismuthate, c. p., powder............... Baker Analyzed 1 oz. eb 57 Vyhhm 4 oz. cb 1.88 Vyhji 1 lb. eb 6.02 Vyhme 5 lb. cb 28.95 Vyhox 10 lb. cb 56.80 Vyhin 5x5 lb.cb 138.75 Vyhyd 5x10 lb. cb 271.50 Vyiaz Me ee Gis Ding eae hice hav tt dapat Baker & Adamson 1 oz. cb -61 Vyign 4 oz. cb 2.32 Vyit7 1 Ib. eb 9.09, Vyikf 5 lb. cb 54.15 Vyimb ss Sie aay sheeaeh dcatacee mente Dees cane agen Merck Blue Label loz.cbh - .80 Vyiso P 4 oz. cb 2.75 Vyiuk 1 Ib. cb 10.00 Vyixe “ Bisulfate, c. p., erystals................. Baker Analyzed 4 oz. cb 24 Vyjfo 1 Ib. cb 56 Vyjig 5 lb. cb 2.25 Vyjle 10 lb. eb 4.10 Vyjnx 25 lb. crock 9.00 Vyirp 50 Ib. crock 17.50 Vyjtl ne €.ips;) crystals instore wk dene Baker & Adamson 4 oz. cb 15 Vykep 1 lb. cb Al Vykih 5 lb. eb 1.75 Vykmz ss c. p., fused (Pyro)............. Baker Analyzed 4 oz. cb .29 Vykae 1 lb. cb .74 Vykzy 5 lb. cb 3.10 Vylbu 10 Ib. eb 5.70 Vyldq ee A eles Bak etedaarcanes Son apr cee dana eee ain hone Merck Blue Label 4 oz. gb 35 Vylke 1 lb. gb -90 Vylmy ‘« Bisulfide, c. p., solution................. Baker Analyzed 4 oz. cb 31 Vyltj 1 Ib. eb .80 Vylof “Bisulfite, U. S. P., dry, VIII (Sodium Acid Sulfite trek his net reece Se ere Merck White Label 1 lb. eb .33 Vymen 5 lb. eb 1.25 Vymif s ee purified, powder Meta, Acid.... Baker Analyzed 4 oz. cb -20 Vymsk 1 lb. cb 44 Vymug 5 lb. cb 1.70 Vymxa es «ep. (Sodium Acid Sulfite)..... Baker & Adamson 4 oz. cb 15 Vynhg : 1 Ib. eb 38 Vynje 5 lb. cb 1.60 Vynly ee aie ear A cera Scere aarp Vente ie eras Merck Blue Label 4 oz. cb 35 8 Vynuf 1 Ib. eb 1.00 Vynyx “« Bitartrate, c. p., powder................. Baker Analyzed 1 oz. cb 18 Vyoel 4 oz. cb AT Vyogh 1 lb. eb 1.34 Vyoid oe BSC Dri opoaust mean ae eae Baker & Adamson 4 oz. cb 41 Vyopo : 1 lb. eb 1.43 Vyork es RC Ra ane reed taee Meme eet Merck Blue Label 1 oz. eb .30 Vypas 8 oz. cb 1.25 Vypek Borate, calcined, powder................ 0 22 eee eee eee 1 Ib. etn 55 Vypmu “U.S. P., refined, crystals......... Merck White Label 1 Ib. ctn 24 8 Vypud 5 lb. etn 1.10 Vypet a “U.S. P., refined, powder......... Merck White Label 1 |b. etn 24 Vyqib 5lb.ctn 1.10 Vyqri fs “fused, ground, anhydrous (Borax eee Gl aSS) eset he eee Mba memento ali wee ata eee Bee aaa 1 lb. etn 48 Vyqgzs 5 lb. etn 2.05 Vyrbo 25 lb. etn 9.25 Vyrdk A R T H U_R H. T H O M A _ S Cc O M P A N Y Item Maker or Brand Size pkg. Price Code Word Sodium Borate, c. p., crystals (Na. B;0,;. 4H.O) Baker Analyzed. 4 oz. cb 25 Vyrjy 1 lb. eb 61 Vyrms 5 lb. eb 2.45 Vyron 10 lb. cb 4.50 Vyrrh 25 lb. box 10.00 Vyrub os ¢c. p., crystals . Apege Nee toe Baker & Adamson 4 oz. cb 19 Vysbn 1 |b. cb 55 Vysdj 5 lb. cb 2.45 Vysgd c. p., anhydrous, powder......... Baker Analyzed 4 oz. cb -40 Vysom 1 lb. eb 1.11 Vysrg 5 Ib. eb 4.85 Vysua au “purest, crystals............. Merck Blue Label 4 oz. cb -40 Vytbm 1 lb. eb 1.15 Vytdi oS SS) “Caleinedinai vs sles De eet Merck Blue Label 4 oz. cb 55 Vytls 1 lb. cb 1.75 Vytol “ Bromate, c. p., crystals. Baker Analyzed 1 oz. cb 21 Vyuan 4 oz. cb 56 Vyucj .1 lb. eb 1.62 Vyuef “ PEP, PACH Rua os) ace NLC eta eye EY ae tlealia Merck Blue Label 1 oz. cb 35 Vyukt “Bromide, c. p., crystals................. Baker Analyzed 1 oz. cb 15 Vyure 4 oz. ecb 31 Vyuta 1 Ib. eb 78 Vyuxrs 5 lb. cb 3.40 Vyuzo 10 Ib. eb 6.20 Vyvei s “ Coan 5 at eve a ee cue etd See a ee Baker & Adamson 4 oz. cb 29 Vyolq 1 lb. cb -95 Vyonl 5 lb. eb 4.45 Vyord “Calcium Hydrate, dry, granular, 4 mesh : (Soda Lime)........... Baker Analyzed 1 Ib. eb 47 Vywbj 5 lb. cb 1.85 Vywdf 10 lb. eb 3.30 Vywfb 25 lb. keg 7.00 Vywhx 50 lb. keg 13.50 Vywyt “ i “dry, granular, 8 mesh... Baker Analyzed 1 Ib. eb AT = Vywre 5 lb. cb 1.85 Vywty 10 lb. cb 3.30 Vywru 25 lb. keg 7.00 Vywyo 50 lb. keg 13.50 Vyxak e as “dry, granular, 12 mesh.. Baker Analyzed 1 lb. eb AT Vyxiu 5 lb. cb 1.85 Vyxnj 10 lb. cb 3.30 Vyzrb 25 lb. keg 7.00 Vyxxp 50 Ib. keg 13.50 Vyzxel ts «dry, 20 mesh........... Baker Analyzed 1 Ib. eb 50 Vyygx 5 lb. eb 2.00 Vyyit 10 Ib. cb 3.60 Vyykp 25 lb. keg 7.75 Vyyml 50 lb. keg 15.00 Vyyog “ i “dry, 20 mesh, low in Chlorin@ 2 asc e8a ees Baker Special 1 oz. cb 13 Vyyzk 4 oz. cb .28 Vyzce 1 Ib. eb 71 Vyzea 5 lb. eb 2.95 Vyzhu “ ee «dry, 40 mesh........... Baker Analyzed 1 Ib. cb AT Vyznh 5 Ib. eb 1.85 Vyerz 10 lb. cb 3.30 Vyzan 25 Ib. keg 7.00 Vyeej 50 lb. keg 13.50 Waadx ‘“ ae “dry, 40 mesh, low in } ? Chlorine ss. h.ccccas ee eae Baker Special 1 oz. cb 13 Waajl 4 oz. cb 28 Waalh 1 lb. eb 71 =Waane 5 lb. cb 2.95 Waaru “ ss “dry, 60 mesh.......... Baker Analyzed 1 |b. eb 44 Waaze 5 lb. eb 1.70 Wabba 10 lb. cb 3.10 Wabeu 25 Ib. keg 6.50 Wabim 50 lb. keg 12.50 Wabdlg “ “ “dry, 60 mesh, low in ; Chlorine Eire eit etn Te Baker Special 1 oz. eb 13° Wabun 4 oz. cb -28 Wabsh 1 lb. cb 71 Wabed 5 lb. cb 2.95 Wacex 73 AD URS “i Cee. “Ur oR H. T H O M A _ S Cc O M P A N Y Item Maker or Brand Size pkg. Price Code Word Sodium Calcium Hydrate, moist, granular, 4 mesh.. Baker Analyzed 1 lb. eb 53 Wacelf 5 lb. cb 2.10 Wacna 10 lb. cb 3.90 Wacqu 25 lb. keg 8.50 Wacsq 50 lb. keg 16.50 Wacum # a ‘“ moist, granular, 4 mesh, low in Chlorine....... Baker Special 1 oz. cb 14 Waddu 4 oz. cb 32 Wadgo 1 lb. cb 84 Wadik e “moist, granular, 8 mesh. Baker Analyzed 1 lb. eb 53 Wadsp 5 lb. eb 2.10 Wadul 10 lb. eb 3.90 Wadyd 25 lb. keg - 8.50 Waeaz 50 lb. keg 16.50 Waecv “ “moist, granular, 8 mesh, low in Chlorine....... Baker Special 1 oz. eb 14 Waeij 4 oz. eb .32 Waekf 1 lb. cb 84 Waemb zy Ry ‘* moist, granular, 12 mesh Baker Analyzed 1 Ib. cb 53 Waeso 5 lb. cb 2.10 Waeuk 10 lb. eb 3.90 Waewg 25 lb. keg 8.50 Waeye 50 lb. keg 16.50 Wafay fe : ‘* moist, granular, 12 mesh, low in Chlorine....... Baker Special 1 oz. eb 14. Wafke 4 oz. eb 32 Wafma 1 Ib. eb 84 Wafov ne “ “moist, 20 mesh........ Baker & Adamson 1 lb. cb 52 Wafxd 5 5 lb. eb 2.30 Wagax fe se es moist, 40 mesh... Baker & Adamson 1 lb. cb 52 Wagih 5 lb. eb 2.30 Wagmz y a “moist, 60 mesh........ Baker & Adamson 1 lb. eb 52 Wagzxe 5 lb. cb 2.30 Wagzy “Calcium Hydrate (Wilson Soda Lime) non- deliquescent, for absorption of COs, or acid gases, 4 to 8 mesh, low moisture; for use in basal metabolism determinations. Wilson............... 1 Ib. etn. -60 Wahdq 10 lb. etn. 5.00 Wahfm “Carbonate, crystals (Sal Soda). ..........0 2c eee 1 Ib. eb .24 Wahmy 5 lb. can 50 Wahot 10 lb. can .70 Wahrn 2 ~ dried powder, technical, (Soda INST eis oe crate eine Grr te ed reats eoaie eivioren Nal Senta | aeohas 1 Ib. ctn 18 Wahxb 5 lb. etn -65 Waiav 10 lb. etn 1.00 Waicr se as H. P., ‘‘e. p.,” dried, contains about 5% water............. Merck White Label 1 lb. eb 33 © ©Waijd 5 lb. ctn 1.10 Waimaz ‘ 25 |b. etn 5.00 Waios fs ef Cs ps, crystaleia ieee Baker Analyzed 4 oz. cb 21 Waive 1 lb. cb 47 Waiza 5 lb. cb 1.85 Wajdo 10 lb. cb 3.30 Wajgit 25 lb. keg 7.00 Wajjc 50 lb. keg 13.50 Wajly s enpecerystalss 14 75 hee kG Baker & Adamson 4 oz. cb 130 Wajyx 1 lb. eb 32 Wakcp 5 Ib. cb 1.30 Wakel a ee Chystalsicc caaecl hows e ean gee Merck Blue Label 1 lb. eb 50 Wakns 5 lb. cb 2.00 Wakpo fs e ¢c. p., anhydrous, powder... Baker Analyzed 4 oz. cb 25 Walhe 1 Ib. cb 59 Walja 5 lb. eb 2.43 Walmu 10 lb. eb 4.40 Walop 25 lb. can 9.75 Walrj 50 lb. can 19.00 Waltf f t c p., anhydrous, powder...... Baker & Adamson 4 oz. cb 18 Wamen 1 Ih. cb Al Wamej 5 lb. eb 1.75 Wamhd es we c. p., anhydrous powder...... Baker Special 4 oz. cb 32 Wamri 1 Ib. cb 84 Wamte 5 lb. eb 3.65 Wamva 10 lb. cb 6.90 Wamyu ss im anhydrous............. Merck Blue Label 4 oz. cb 35 8 =©Wanei 1 Ib. cb 1.00 Wanhc 5 lb. eb 4.50 Wanjy “- Carminate............................ Coleman & Bell 10 gram gv 2.00 Wanrh 74 A OR. TF Be YR H. T H O M A _ S Cc O M P A N_ Y Item Maker or Brand Size pkg. Price Code Word Sodium Caseinate, see NUTROSE. Seep Teco terraces | eur i Oi “Chlorate, U. S. P., crystals. .. ee... ....... Merck White Label 1 lb. eb .38 Wanzr 5 lb. eb 1.45 Waobn _ fe c. p., erystals................. Baker Analyzed 4 oz. cb -26 Waokv 1 Ib. cb 64 Waomr 5 lb. cb 2.70 Waoom 10 lb. cb 4.90 Waogqi e “s OED eset een) pat and raen bee ear g Baker & Adamson 4 oz. cb 21 Waoys 1 lb. eb 64 Wapao “ Cloride, U.S. P... 22.220... )~ Merck White Label 1 Ib. etn -20 Wapku 5 lb. etn 85 Wapmq te eS c. p., erystals................. Baker Analyzed 4 oz. cb 33 Wapzxt 1 lb. eb 86 Wapzp 5 lb. cb 3.65 Wagef 10 lb. cb 6.80 Wagqix 25 lb. keg 15.50 Wagar 50 lb. keg 30.00 Waqnm ss a Gi Pej Crystals’. « aa aganthee Wane e Baker & Adamson 4 oz. cb -20 Waquy 1 lb. cb 61 Wagzxs 5 lb. eb 2.75 Wagqzo a Red esr Aenea eee Acer pre Ona Merck Blue Label 4 oz. cb 30 = ©=©Warga 1 Ib. eb -60 Wariww 5 lb. eb 2.50 Warks ee = c. p.,fused................... Baker Analyzed 4 oz. cb 46 Warrd 1 Ib. cb 1.29 Wariz eS ne Cs Ps, USER ten Po aban Baker & Adamson 4 oz. cb -26 Wasch 1 lb. eb .84 Washx ee s MUSE Cy !s8- Sek cand eevee don babe Absa) S Merck Blue Label 4 oz. cb .40 Wasot 1 lb. eb 1.25 Wasrc ““ Chromate, c. p., crystals................ Baker Analyzed 1 oz. eb 15 Wasem 4 oz. cb .38 Watbi 1 lb. cb 1.03 Watec is ~ ce. p., fused, powder........... Baker Analyzed 4 oz. cb -50 Wauaj 1 lb. eb 1.44 Waucf ss e C. Peo... ee eee eeess+...... Baker & Adamson 4 oz. cb 36 © Waujr 1 lb. cb 1.24 Wauln f Gitrate UieSs Pics bee oes eed Merck White Label 1 Ib. eb 1.16 Wausy 5 lb. cb 5.55 Wauxo es es Cups Crystals sn Asan ane nas Baker Analyzed 1 oz. eb 19 Wavfy ‘ 4 oz. eb 53 Wavis 1 Ib. cb 1.51 Wavlm 5 lb. eb 6.85 Wavnh < BO ACD taka iad rhe metenamnd amen Baker & Adamson ’ 4 oz. cb 45 Wavyl 1 lb. cb 1.60 Wawah 5 lb. cb 7.70 Wawced ‘“ Cobaltic Nitrite, c. p., powder, for Potas- sium determinations..... Baker Analyzed 1 oz. cb .68 Wawjp fe ae “for Potassium determina- HONSi sss ho ee ee es ‘Baker & Adamson 1 oz. cb 66 Wawga fe ue s Solution: ss. 4 2977 we eases Merck Blue Label 1 oz. gb 30 Wawxm 4 oz. gb -70 Wawzi “ Cyanide, 96-98%, U. S. P., for technical and insecticidal use... 0.0... ee eee 1 Ib. can 55 Waczhs 5 lb. can 2.60 Waxjo ss -@. pe Granular oc40 adage wis Baker Analyzed 4 oz. cb 36 4 ©Wazrer 1 lb. cb 98 Waxzal 5 lb. cb 4.30 Waxzh 10 Ib. eb 8.20 Waybd fe fhe AGL ADS tau yg 4 Mea eee es te Baker & Adamson 4 oz. cb 32 Wayip 1 |b. eb 1.06 Waykl “ bE en pe ayes nts ead en a Merck Blue Label 1 oz. gb 25 Waysu 8 oz. gb 75 = Wayug “ Dicarbonate, pe OpLeM BICARBON- “ ide, c erystals............. Baker Analyzed 4 oz. cb Al Wazdy Feocyen eee eee Llb.ch = L12s Wazfu 5 lb. cb 4.95 Wazto cs i Hnicals POWder soccer 1 lb. ctn 27 = Wazst ae a rere Blb.ctn 1.00 Wazup “ oS . Dp. eh iil Sees Baker Analyzed 4 oz. cb 35 Weacr Cee 1 Ib. cb "92 Weaen 5 lb. eb 4.05 Weagj 10 lb. eb 7.70 Weajd 15 As Re UT SH eR H. T H O M A S CO MM P A N Y Item Maker or Brand -Size pkg. Price Code Word Sodium Fluoride, ¢. p...........0..0.0 000 ceca Baker & Adamson 4 oz. cb 25 Wearm 1 lb. cb 81 Weati ““ Formate, c. p., crystals................. Baker Analyzed 1 oz. eb 21 Webbs 4 oz. cb 58 Webem 1 lb. cb 1.70 Webgi 5 lb. cb 7.80 Webie * “Glycocholate s+ c..s00 se soe eS Difco 1 oz. cb 75 Websj 1 lb. eb 10.00 Webuf “* Hydrate crude, powder, 94% (Caustic SOd8) 425.5 powanaeace tee anmcenak) —hentrenn ee eain anes 2 Ib. can 36 8 =©Wecel 5 lb. can 80 Wecid 10 Ib. can 1.40 Weelx 24x5 Ib. case 14.40 Wecns 12x10 lb. case 13.20 Wecpo “* purified, sticks. ................ Merck White Label 1 Ib. eb AZ Wecxy oe “« pure, flake, for Nitrogen deter- MInatloOn. 4.2 Sie awh ovens oe ee Baker Analyzed 1 Ib. cb 38 Wedfi 5 lb. cb 1.35 Wedic 10 Ib. can 2.40 Wedky 25 Ib. can 5.25 Wednr 50 Ib. can 10.00 Wedpn ie “electrolytic, lump.............. Baker Analyzed 1 Ib. eb 34 Weear 5 Ib. can 1.15 Weedl 10 lb. can 2.00 Weegf “pure, sticks, electrolytic......... Baker & Adamson 4 oz. cb 18 Weemt 1 Ib. eb 52 Weepm 5 Ib. eb 2.30 Weesg he re te SS PAP StleKsta. oc as ha cssuecneners Baker Analyzed 4 oz. cb 21 Weezs 1 Ib. eb AT Wefbo 5 Ib. eb 1.95 Wefei 10 lb. eb 3.30 Wefge 25 Ib. can 7.00 Wefia 50 Ib. can 13.50 Weflu my “ e. p., by Aleohol, sticks......... Baker Analyzed 4 oz. eb 27 = =Wefub 1 Ib. eb .67 Wefzr 5 Ib. eb 2.75 Wegbn 5 Ib. can 2.70 Wegeh 10 lb. cb 5.10 Weghb 10 Ib. can 5.00 Weglt 25 Ib. can 11.50 Wegno 50 lb. can 22.00 Wegqi es “© pure, by Alcohol, sticks........ Baker & Adamson 4 oz. cb 24 Wegys 1 Ib. cb 74 Wehbm 5 lb. cb 3.40 Wehdi sf SES SDUPO esd. ak oudeie a iar esters Cane occ eek Merck Blue Label 4 oz. cb 35 Wehku 1 lb. eb 1.00 Wehmgq “ SS purified sas ekiee wes aves Merck Blue Label 4 oz. cb 30 8 Wehzxt . 1 Ib. eb -75 Wehzep SS “free from Nitrogen, sp. gr. 1.3 AVOUT ZT isc oaks ss cto eee Merck Blue Label 1 Ib. cb 80 Weifd s “from Sodium.................. Merck Blue Label 1 oz. cb 25 8=6Weilr 7 ‘ fy = 65 Weinm s 00 ipt of “Standardized Buffer Solution, nor- r Went mality M-5, (CO: free).......... La Motte 500 ml. gb 4.00 Weizo 1000 ml. gb 5.00 Wejci «« Hydrate Asbestos, absorbent, see ASCAR- ITE. For the determination of carbon in steel by the direct combustion method p aeeoneing to Stetser & Norton. PAU a enter es ae MPa at oot ANS ee wR ee “‘ Hydrosulfite, powder... . 1.0.2.2... 0.605 cece cece ees 1 Ib. eb 1.40 Wejnl ‘* Hypochlorite eee Chlorinated) see BARRAQUE’S SOLU- TION id idun tenance dimemtinvedemakahe roe k Sup ER keen t “« Hypophosphite, U.S. P................. Merck White Label 1 lb. eb 1.35 Wejzn se ie c. p., erystals............ Baker Analyzed 4 oz. cb 60. Wekkr A ee 2 nee Wekmn “ Hyposulfite, see, SODIUM THIOSUL- ne ae ee 4 Indigotin, see INDIGO CARMINE....... ................... eae “ Indigotinsulfonate...................... Merck Blue Label + oz. eb 20 + Wenjq % 0z. cb 50 Wenlm 76 aR oe es H. T H OF M A _§S Cc O M P A N Y , Item Maker or Brand Size pkg. Price Code Word eociom Todate, c. p., powder................... Baker Analyzed 1 oz. cb 84 Wekvu CAPs rates cease eas reps anda Baker & Adamson 1 oz. cb .79 Welde 4 oz. cb 3.06 Welfa 1 lb. cb 12.04 Weliu re Vodide; Ui Pas chscrs eacncs eon tes Be Merck White Label 1 oz. cb 42 Welrb 4 oz. cb 1.25 Weluv : ; 1 lb. eb 4.50 Welxp Cee Phe eseeens stil wala ge olingun tees So ngiess Baker Analyzed 1 oz. cb A8 Wemeb 4 oz. cb 1.55 Wemhv 1 lb. cb 4.94 Wemjr 5 lb. eb 23.70 Wemni REP AOD renders intl Pad ties Picea ae Baker & Adamson 1 oz. cb 73 Wemzxo 4 oz. cb 2.82 Wemzk 1 lb. cb 11.08 Wence Se, Lactate 0st peace aerate ae ee reece eee ee 4 oz. cb 58 Wenor n 1 lb. eb 1.78 Wenyl Molybdate, c. p., powder................ Baker Analyzed 1 oz. cb .33 Weoez ¥ 4 oz. cb 1.01 Weoht Monosulfonate Alizarin, see ALIZARIN SODIUM MONOSUL- PONATE Ee tormurete iad domme eiwidapitiy, Salant tes “ “Nitrate; technical, crystals. icsccacdeeed. waauceea eed be es 1 Ib. ctn -20 Weoga 5 Ib. box .80 Weotu : 25 lb. pkg 3.00 Weovg os “ep. crystals)... 0.0.00... 00. Baker Analyzed 4 oz. cb 24 Wepbe : 1 lb. cb 56 Wepey 5 lb. cb 2.25 Wephs 10 lb. eb 4.10 Wepjo 25 lb. keg 9.00 Weplk 50 lb. keg 17.50 Wepnf a “ORD: serystals s+ sucmaence ees Baker & Adamson 4 oz. cb 16 Wepyj 1 lb. eb 45 Wegexr 5 lb. cb 1.95 Weqip is BE SCs ADs {SUICKS 5.5 eek os Sot ne eg Baker Analyzed 4 oz. cb .32 Weqoc 1 lb. cb 84 Wegay ue EE oN a Shae aes tan tira skh herded i Merck Blue Label 4 oz. cb 30 Wegzeg 1 lb. eb 80 Werbc ““ Nitrite, technical, granular.............. 0 fcc eee cece 1 lb. eb 36 Werhq 5 lb. cb 1.30 Werjm i “ @p., erystals........... De ee Baker Analyzed 4 oz. cb 25 Wergx 1 lb. eb 59 Werst 5 lb. cb 2.40 Werup 10 lb. ecb 4.40 Werxj 25 Ib. keg 9.75 Werzf 50 lb. keg 19.00 Wesev SE CGS DE ACTYStAIS® Gavia ine Ieee te Baker & Adamson 4 oz. cb -20 Wesoa 1 Ib. eb -60 Wesru 5 Ib. cb 2.70 Wesxi £% 2OSD, .SbICKS evn dukes i ee teeae bake Baker Analyzed 4 oz. cb 28 Weteu 1 lb. eb 74 Wetim 5 Ib. cb 3.10 Weilg 10 lb. cb 5.70 Weinb 25 lb. can 13.00 Weirt 50 lb. can 25.00 Wetun ee AES SOs PaysStlCKSe in cucu ee en Baker & Adamson 4 oz. cb 23 Weudv 1 Ib. eb 71 Weufr 5 lb. cb 3.25 Weuhn * RES eas tia a. tinai,ate nanny heaire mh Gr Uaias Merck Blue Label 4 oz. cb 40 Weuqu 1 Ib. eb 1.25 Weusg ‘Potassium free..............6-6. Merck Blue Label 1 oz. eb -20 Weuye 8 oz. cb 75 Wevby “ Nitroferricyanide, c. p., crystals (Nitro- ie prusside)............. Baker Analyzed 1 oz. eb 70 = Wenjt es of (Nitroprusside)........ Merck Blue Label + oz. cb 35 Wevrtn , 1 oz. cb 1.00 Wevrj “ Nitroprusside, see SODIUM NITROFER- RIGVANIDE ee ee Gaeeincieteeee yo ee area “ Oleate, powder neutral...........-..---- Merck White Label 4 oz. cb 30 © Weufp 1 Ib. eb 94 Wewiz ‘“* Orthophosphate, see SODIUM PHOS- : PHATE TRIBASIC ies. Gecuitioeticeiies ena ee eae A OR “EA 0) eR H. T H O M A _ S Cc oO M P A N Y Item Maker or Brand Size pkg. Price Code Word Sodium Oxalate, c. p., powder.................. Baker Analyzed 1 oz. eb 15 Wexhk 4 oz. cb 37 Werlc 1 lb. eb -98 Wexov 5 lb. cb 4.30 Wexsn 10 Ib. cb 8.20 Wexruj . Fe EGE) TaGeigs sete A a a ho Baker & Adamson 4 oz. cb 39 Weydr 1 Ib. cb 1.35 Weyfn a “ —¢e.p., for standardizing. According to: Sorensen... 4. cs keen das Baker Special 1 oz. cb 29 Weyou 4 oz. cb 86 Weyro 1 Ib. eb 2.64 Weytk 5 lb. cb 11.50 Weywe * “Perborate US. Pe cacao cat 3a5 Saas Merck White Label 4 oz. ctn 21 Weecs 1 |b. etn .70 Wezhi - a CoP. DOW? 28 Sth vane seed Baker Analyzed 4 oz. cb .38 Wezot 1 lb. eb 1.05 Weesl ES RR ry er ae ena er aa Merck Blue Label 4 oz. cb -60 Whadj 1 lb. eb 2.00 Whahb Si Peroxide; 92-90 Ge ch recit oinse era tun scatman ccees choc nee 4 oz. can 25 Whaom 1 lb. can 85 Whaqi ie iS special grade for Parr Calorimeter ................... 4 oz. can 95 Whays 8 oz. can 1.50 Wheal 1 lb. can 2.25 Whech a sf GD ovis meatal an usatinace ahd > eer Baker Analyzed 1 oz. can 15 Wheiv : 4 oz. can .33 Whekr 8 oz. can 52 Whemn “ of c. p., for Coal analysis, low in Saltire 2 a6 Gen Avent no is Baker Special 4 oz. can AT = Whevu 8 oz. can 78 Whexq Be BS Bc a rah ener Ces ear ae neti ee Merck Blue Label 100 gram gb & tin 1.00 Whidb te eiPersulfates Cpt. sshsaas h autocaais eases a Pfanstiehl 1 oz. eb .35 Whikn 1 lb. eb 3.50 Whing “Phosphate, Di-acid, see SODIUM PHOS- PHATE MONOBASI@iiccainc9 Gsacttiseecmiciae: 1Ghbaee, ceva - fs Dihydrogen, se SODIUM PHOSPHATE MONOBASIG: - “Sulfuric, 1-50 Normal... ................... 500 ml. gb 1.00 Wrihy 1000 ml. gb 1.55 Wriks ae = . * “Decinormal..:. cscacceenes 500 ml. gb 1.00 Wrird 1000 ml. gb 1.55 Writz os i < “7 MNormaly..cgseh, Aossace nek 500 ml. gb 1.00 Wroag 1000 ml. gb 1.55 Wroda a " ‘“ 2g Normal.... Pfanstiehl 4 oz. gb .60 Wrokm 1 lb. gb 1.75 Wromi eS es Potassium Hydrate, 1-50 Nor- mal (AQueous):< sews Shes deg agarend fee te: 500 ml. gb 1.17 Wrovp 1000 ml. gb 1.72 = Wrozl c i Potassium Hydrate, Decinor- mal (AQUEOUS) ..2 cfo uric het. eben der a Roane 500 ml. gb 1.17 Wrufq 1000 ml. gb 1.72 Wruhm a “ Potassium Hydrate, Normal (AQUEOUS) aire sme hpraeencitis Surawden sae Seachem Sie ce tees 500 ml. rb 1.17 Wruox 1000 ml. rb 1.72 Wruaqt *s * Potassium Permanganate, Décinormaliicem cee ake sags head nee: 500 ml. rb 1.25 Wruyd 1000 ml. rb 1.80 Wryaw : . Potassium Permanganate, 5.76 grams per liter. As used in routine iron analysis........ 0 ........... 1000 ml. gb 1.80 Wrygk a a Sodium Hydrate, 1-50 Normal ................... 500 ml. rb -92 Wrymy 1000 ml. rb 1.47 Wryot a se fs es Decinormal ............ 500 ml. rb -92 Wryof 1000 ml. rb 1.47 Wryxb 1 Ae ‘ fe Normal.... ........ 500 ml. rb 92 Wuaeg 1000 ml. rb 1.47 Wuage s os Sodium Thiosulfate 1-50 Nor- TINA S aaN herrontk Aeodelten ha oa ete Sins AA NA EA Po Son Ge eG 500 ml. rb 1.17 Wuapj 1000 ml. rb 1.72 Wuarf as ss Sodium Thiosulfate, Deci- MOPMAl sex cve wenn: eM aus ki eutegebcamanee ee 500 ml. rb 1.17 Wuazp 1000 ml. rb 1.72 Wubdix ss - Sodium Thiosulfate, Normal ................... 500 ml. rb 1.17 Wubre 1000 ml. rb 1.72 Wubta os Water Testing for Chlorine,see SOLUTION TOLIDIN ORTHO 45% in 10% HYDROCHLORIC ER CID ite iticcrdciseniirweceiee eomkuiahetiee peu nsy RANE) ees GOLD LO os eet se ets eR osteo ty RaM See Pfanstiehl 1gramcb 2.00 Wucam Spirochaete Solution Giemsa, see SOLUTION GIEMSA:[SPIROCHAIT RE... gomicneticwasewehes “Gaateiass 282ue Splints, see WOOD SPLINTSst.5 -nsccarthos ie) RUSRo ieee | ae | tea Stannous, see TIN (STANNOUS).............5.0 cece eee eee ee ee Starch, Arrowroot, powder..............---..5:. Baker Analyzed 4 oz. cb 33 Wucks 1 lb. eb 87 Wucmo Oe OER Ree a Nee aes PLA SEELEY Uae 1 Ib. etn 14 Wuetz Ee NI ZOU esas een nee es RE Merck White Label 1 oz. cb .33 Wudch a 4 oz. eb "80 Wuded es Pat Oe ir cates eet aiie Nees Becca e etica. Gaundp centage cereates eee 1 Ib. etn 35 Wudnk oy 5lb.ctn 1.45 Wudge es ble, according to Lintner............ Merck White Label 4 oz. eb 46 Wudxq Soluble 2 Llb.cbh = 1.46 Wudzm 83 Ae Re He UW ER H. TT H O M A S CO M P A N_ Y Item Maker or Brand Size pkg. Price Code Word Starch Soluble, c. p., powder.................-. Baker Analyzed 4 oz. cb 45 Wuefa 1 lb. cb 1.26 Wuejs 5 lb. cb 5.65 Wuenj 10 lb. cb 10.80 Wuepf 25 lb. can 25.00 Wueuv 50 lb. can 48.00 Wuewr “S “Sugar; 'see-DEXTROSE:ccaueisicaieaks Sitrcie eee eeeis. -cagieceis walt “Wheat, powder..............00cc eevee Baker Analyzed 4 oz. cb 22 © Wufef 1 lb. cb 50 8 Wuffz 5 lb. cb 1.95 Wufir Stopcock Grease, ‘‘Lubriseal’’ a rust-proof lubricant, nearly acid and alkali-proof, for use with either metal or glass stopcocks. Melting : pointsapprox: 48°C sh S255 east ewan ees 1 oz. tin 35 Wufra Strontium Acetate, c. p., crystals................ Baker Analyzed 4 oz. cb 45 Wugce 1 lb. eb 1.26 Wuogfy oe Carbonate, N. F. (precipitated) powder .................04. 1 lb. cb 65 Wugnh « s Ce Pe POWERS 2 os Snorer ae Baker Analyzed 4 oz. eb .38 Wugrz 1 lb. eb 1.05 Wugxen ss GRP aac fag em casei eee es gee Baker & Adamson 4 oz. cb 30 Wuhfx 1 lb. eb 1.01 Wuhht ms a c. p., Barium free,......... Baker Special 1 oz. cb 21 Wuhoe e Chloride, pure, crystals............... Merck White Label 4 oz. cb 19 Wuhvq 1 lb. cb AT Wuham os Ef Ges cCRV Stal Sh vce sheen oe Baker Analyzed 4 oz. cb .30 Wuigu 1 lb. eb 77 Wuiig 5 lb. cb 3.25 Wuikm ‘ Cs Py CrystalSis sete ele aie Baker & Adamson 4 oz. cb 23 Wuirx 1 lb. cb 72 Wuiur 5 lb. cb 3.30 Wuiwn ie Chromate, c. p., powder.............. Baker Analyzed 1 oz. cb 23 Wujip 4 oz. cb -66 Wujkl 1 lb. eb 1.94 Wujne ie Hydrate, c. p., erystals............... Baker Analyzed 1 oz. cb 23 Wujvo 4 oz. cb -66 Wukae 1 lb. cb 1.96 Wukdy Sf - Nitrate) Qly:s 5 6) Gwen Sh ee ee Merck White Label 4 oz. eb 19 Wukmg 1 lb. cb .40 Wukob eo SS SC Pig CLV StAlS rants rse ek Baker Analyzed 4 oz. cb 38 Wukzf 1 lb. cb 92 Wulcz 5 lb. cb 4.05 Wulev 10 lb. eb 7.70 Wulgr re ESD OSD a8 Geb ieetiny cae outs aan ene Baker & Adamson 4 oz. cb 29 Wulmf 1 Ib. cb .95 Wuloa & “¢. p., crystals, Barium free..... Baker Special 4 oz. cb -49 Wulyg 1 lb. eb 1.40 Wumac “f Oxalate, c. p., powder................ Baker Analyzed 1 oz. cb 19 Wumim 4 oz. cb 49 Wumki 1 lb. eb 1.40 Wumme ss Phosphate, c. p., powder.............. Baker Analyzed 4 oz. cb 54 Wumyf 1 lb. eb 1.57 Wunab ss Sulfate c. p., powder ................. Baker Analyzed 4 oz. cb 35 Wunil 1 lb. eb -95 Wunlf a Bed Cea mrs aR hoe ae eer 7 SR Baker & Adamson 4 oz. cb 30 Wunto 1 lb. eb 1.00 Wunwi as Sulfide, powder...................... Baker Analyzed 1 oz. eb 23 Wuoes 4 oz. eb -66 Wuogo 1 lb. eb 1.96 Wuoik Sucrose; see SACCHAROSE 4.0): stig cc kawiaier Ciatues oles. 9) outeesk RERCRL Sudan weet cw ststaar stra ne sures east aa opens aes Coleman & Bell 10 gram gv 70 Wuopv 2 ‘1 Sugar Agar, Krumwiede, dehydrated see AGAR Daren Petede Palaces AGAR TRIPLE SUGAR, DEHY- DRA ED occ cretgut henna anh anh aterm op «Milenio et SO Syrup Inverts shee haices: ser aoranesena pene Difco 4 oz. cb 65 Wuozb 1 lb. eb 1.50 Wuper “Sof Lead, seesBAD ACH TAT jusncceatens a ee Oe gy eeu al Sulfide Cubes, for generating H2S...........002.0 Ce, 1 Ib. eb 60 Wupny Sulfite Cubes, for generating SO2..... ohne ORE cee hod 1 lb. cb 55 Wupvi Sulfur, Roll (Brimstone)... c..5 wroic sce ccegeaes gu eaaneeee eae cieons 1 lb. ctn 15 Wugeg 5 lb. ctn 45 Wugke 10 lb. pkg -60 Wuqma A R T H U R H. TT H O M A S CC OF M P A N Y Item Maker or Brand Size pkg. Price Code Word Sulfur, Sublimed U. S. P., powder (Flowers of Sul- Pa) Siter Rearing Anan taht ein A he ghisbon ep ePe hee eames 1 lb. ctn 16 Wuged 5 lb. ctn 45 Wurax ie oe 10 lb. ply .60 Wuret i U.S. P., precipitated. ............00.00.. Merck White Label 1 Ib. ctn -40 Wurih x washed, U.S. P., powder................. Merck White Label 1 Ib. etn 22 Wurps CTY StalS tte cian aes er aan etiie tute e aac Baker & Adamson 4 oz. cb 16 Wurxe = . a 1 lb. cb 45 Wurzy Chloride, liquid (Monochloride)........... Merck White Label 1 lb. gb -70 Wushi “© Monochloride, see SULFUR CHLORIDE... .............002225200 beeen eee tee ee Superoxol, se HY DROGEN PEROXIDE 100 vol- umes Oxygen, about 80% H.0O, by WEIPNG eo iA ek bite trae eun” tle meal aaah aaleeday ‘Taka: Diastase; powder 2.0) de ene eh cc ne aielnne Tata neneBany SEE eee 1 oz. cb 1.90 Wusot Talcum, powder, U.S. P., purified............... Merck White Label 1 Ib. ctn 18 Wusyz 5 lb. ctn 75 Wuter Tannin, see ACTD TANNIC: iics.e ckacibveeres AGieecdeisweblen SHAN: actaite Tartar Emetic, see ANTIMONY POTASSIUM TARTRA TH cee aaa eeemree es Aa Oeostiwy Test Paper, Congo, in sheets 8x10”... 10... 62.66, ce es 1 sheet -05 Wutnu 1 quire -60 Wutgo oe “in vials of 100 strips 2x14”.... 0 0... eee eee 1 vial 10 Wutsk 12 vials 95 Wutug ns ‘« Litmus, blue, in books of 25 strips 2x14” Rede ahn icant Reena one: 1 book 05 Wuuem 12 books .50 Wuugi 72 books 2.40 Wuuor 144 books 4.32 Wuurl aS ie ¥ i (SEAN OUS) xi oe ey at Sa Merck Blue Label 1 oz. gb 35 Wyrpk fight sy apes 8 oz. gb 1.50 Wyrrg x : solution (Stannous)........... . Merck Blue Label 4 oz. gb 55 Wyre 7 1 lb. gb '1.60 Wysbm “ Oxalate, c. p., powder (Stannous)............ Baker Analyzed 1 oz. eb +22 Wysiy 4 oz. eb 62 Wysis ss 1 lb. cb 1.83 Wysol “ Oxide, c. p., powder (Stannic)............... Baker Analyzed 4 oz. eb 41 Wyszp 1 lb. eb 1.15 Wytef “se. p., powder (Stannous)............. Baker Analyzed 4 oz. cb -66 Wytok 1 Ib. eb 1.94 Wytre ‘“* Protochloride, see STANNOUS CHLORIDE.. .............00000.00 cece bees “ Sulfate, c. p., powder (Stannous)............ Baker Analyzed 4 oz. cb Al Wytzo ; 1 lb. eb 1.15 Wyubk ‘itanpum:e Metalices pi. a is kee eel ade ae ¢Aeeedees yes 1 gram gv 55 Wyuju 3 ‘ 1 oz. cb 6.50 Wyulg¢. us Dichloride! (Titanous Chloride) (TiCl,) .......... 1 oz. gb 1.50 Wyurd “Oxide, Anhydrous (Acid Titanic)....... 0 ..........0....00.. 1 oz. cb 57 = Wyuyp 1 lb. eb 7.35: Wyval < “ ¢. p., anhydrous (Acid Titanic An- TAVGROUS) count eyecare cae ak) ae CR A nes ieeA tea 1 oz. cb 1.25. Wuyvnk 1 lb. cb 15.00 Wyvge “ef Potassium Oxalate, c. p., crystals....... Baker Analyzed 1 oz. eb 15 Wyvxq - SSulfatey puree cx cote ac Meee RS Sei uke tiie dies ee 10 gramcb 1.65 Wywoh 1 oz. cb 4.00 Wywyn “ Tetrachloride, liquid.................. Baker Analyzed 1 oz. cb 24 Wyxrml 4 oz. cb 58 Wyxog 1 lb. cb 1.51 Wyxra Toi ’§- Blood Solution: 535 gee uk tie AAs ee cues Rie ee 1 oz. cb 25 Wyybg ere 8 oz. cb 1.50 Wyydc «* Blood Fluid Tablets .................. Soloid tube 6 tablets .35 Wyyko Tolidin Ortho, purified by Alcohol, for Chlorine test OL Waterss tA eee c alain Abas Gaede ena ging ta 1 gram gv 10 = Wyyut . 5 gram gv 35 Wyyzrn . 25 gram cb -80 Wyzah Tolu Balsam for diatoms................--.-5-. Grubler 100 gram cb_~——:1.00 Wyeng Toluene, see TOLUOL. ...... 060-6 nett tee eee idi Mie een tre ae care reer ae Coleman & Bell 10 gram gv -90 Wyzwo Tolmidine Blue 25 gram gv = 2,00 Wyzyk ee Ortho, solutioix.cacciecuntte ee Sea ees ees 1 Ib. eb .75 Xaaim “ SEV tate kee ae Ne ee Sea ears 1g eid Nee one a cea te Cee 4 oz. eb -90 Xaaoz Pate ey 1 lb. eb 2.80 Xaasr 2 eee ae Mitchel ey caine cnca cnet Maen Pace RUD Met LYRE eet a 1 pt. eb .39 Xabab Toluol, (Toluene) com ean 1.49 Xabet 5 gal. can 4.95 Xabhn IThis is recommended by the U. S. Department of Agriculture, Bureau of Animal Industry, Dairy Division, and may be used in the Volumetric method of determination of Hydroxylamine, according to Bray, Simpson & McKenzie. 87 AR. “T(E Ur eR H. T H O M A S§S CC -O? M) (P2 AT -N@ ¥ Item Maker or Brand Size pkg. Price Code Word Toluol, (Toluene) pure...... ee aoe eee ea tale Ame) pina hrueh west Mens Bic eee 1 pt. cb .40 Xabrs 1 gal. can 1.50 Xabum 5gal.can 5.00 Xabye CoD A EH a RO noe SRO Baker Analyzed 1 lb. eb 62 Xachm 5 lb. cb 2.55 Xacjt 10 Ib. can 4.80 Xacme 25 lb. can 11.60 Xacox 50 lb. can 21.50 Xactn TrehalOs@w <5 danondioeiess bb eee Ea Difco lgramecb- 1.25 Xaddt 10 gram cb 10.00 Xadij Tri-Acid Stain, cEy, see BIONDI-EHRLICH- EIDENHAIN TRIPLE STAIN meet Slaten Gegeinc Badin s ene Re ekers Ly EEN Eetitce SER on ete Ss “* Solution Ehrlich, see EHRLICH TRI-ACID STAIN SOLUTION (scceceeesecauseieag wee eatee See tes Trikresole ese bec eee onto ae ee pee a ee Schering 1 lb. cb 75 Xadrq 5 lb. cb 3.50 Xadim Trioxymethylene, U.S. P. (Para Formaldehyde)... Merck White Label 4 oz. cb A3 Xaecu 1 lb. cb 1.25 Xaeeq Tripoli; TegrOUNG nce aya ce eee Ramet eee ee 1 lb. etn 15 Xaema Tropaolin, O, pH range11.1-12.7 ................ Coleman & Bell 10 gram gv 60 Xaeil 25 gram gv--1.60 Xaevh fe OO idk Sonal a ne A eae Coleman & Bell 10 gram gv -60 Xafep 25 gram gv-_—ss: 1.30 Xafgl Hy “ pH range 1.4-2.6.................. Coleman & Bell 10 gram gv -60 Xafsm 25 gramgv 1.30 Xafwe ae OOOPNG: Tes ie eee ae Coleman & Bell 10 gram gv .50 Xaghi 25 gram gv-—s—:1.00 Xagje ff “ pH range 7.6-8.9................ Coleman & Bell 10 gram gv 50 Xaguh 7 25 gram gv —i1.00 Xahav TRYPSIN: 4s Se ae a Be FS epee Difco 1 oz. cb -60 Xahif - “ 1A fluid preparation of an active tryptic ; enzyme from the pancreas.............. Difco 10 ml. ampoule .35 Xahqo 12x10 ml. ampou- les 3.75 Xahsk 6 boxes 12x10 am- poules 21.00 Xahug 12 Hove 12x10 am- poules each 39.00 Xahxa Try ptOphAW soe Nas Aa aed dawm ee bese wes Pfanstiehl lgramcb 7.00 Xaihg 10 gram cb_ 65.00 Xaika Tungsten Metal, H. P. powdered ..........-006- eee eee eee ees 1 oz. cb 2.00 Xaith ne Oxide, technical, see ACID TUNGSTIC THCH PO W.D scacaticg toy rtearay. (SEMA E anda name es “ —ep.,see ACID TUNGSTIC,¢.p. .......---.. 0-0 eee Turkey Red Oil,see OIL TURKEY RED........ 0 2.06... eee ee Turmeric Paper, see TEST PAPER............. 0 fee e eee ete ee nee *e DOWOED at Grsonae Wahi al mnt henner “urement ee eat Res ea 4 oz. ctn 13 Xajel 1 Ib. etn 35 Xajjb Turpentine, Ozonized.........0. 66 eee eee een eee ee 120 ml. gb 1.25 Xajrk 500 ml. gb 3.50 Xajue Rectified; U..Si Poca ncp gt eect aan as Merck 1 lb. eb 55 Xakdm ee ViGHICO: colle ce Lee Quaeipe ee Clim ei eotinrened 1 Ib. cb 63 Xakky es WiGeu COM enetectese steerer te te erdee Wahine cata aati eho ona turangn 1 pt. eb 35 Xakyp . 1 gal. can 1.50 Xalar 5 gal. can 7.00 Xaldl TyrOsiNe) 6.23687 ee Ae ee et Pfanstiehl lgramcb 1.50 Xallv 10 gram cb 10.00 Xalpm Uranium Acetate, c. p., (Uranyl)................ Baker Analyzed 1 oz. gb 89 Xalwy “ ES CDi ea et a ES Baker & Adamson 1 oz. gb 86 Xamia 4 oz. gb 3.34 Xamlu “a f¢ free from Sodium............. Merck Blue Label 1 oz. cb -70 Xamer 4 oz. cb 2.30 Xanbn ss Nitrate, c. p., crystals (Uranyl)......... Baker Analyzed 1 oz. gb -60 Xanno ee fe Miedejn de Bienbins eid kiaeepeeas. Merck Blue Label 1 oz. gb 45 Xanxu 4 oz. gb 1.50 Xanzq “ Sulfate, free from Sodium.............. 22... Rjui Seamiarsclaaeiees 1 oz. eb 1.30 Xaoha 1Used in blood culture work to prevent clotting and to impair the bactericidal power of serum, and thus facilitate the growth of suspected bacteria, especially in the identification of typhoid fever, pneumonia septicemia, pyemia, cholera, etc. See Journal of Labora- tory and Clinical Medicine, Vol. 2, No. 3, p 198. 88 AUR TT -H UR H. fo M.A S G -O: (Me cP A UN, CY: Item Maker or Brand Size pkg. Price Code Word rede seates suka ee eases Cen Cech ds kaa Merck White Label 1 oz. cb .29 Xaosd 4 oz. cb .80 Xaozxt PiariCeaD va CLV SLASH Cth ian ne, ran Sete aaa ees Baker Analyzed 1 oz. eb 27 XAapok Urease, 'Dunning, for the estimation of urea in urine and blood. Marketed only in 25 mg.tablets ................... box 40 tb. 1.00 Xapwu box 1000 tb. 10.00 Xapzo *In soluble tablets 0.1 gram each, for the rapid determination of urea in urine, blood, spinal fluid or other body tissues......... Squibb : 10 gram cb: 11.50 Xagrd Wre thane: neces eee ee ta Oe ee earcsh ee Merck White Label 1 oz. eb 50 Xared 4 oz. cb 1.75 Xarip 1 lb. eb 6.00 Xarot Uric Acid, see ACID URIC.... Vanadium Metal, electrolytic . . oe Aree eee ahem techie chao a) une nash ere i 10 gram gv 3.50 Xarvu 1 oz. cb 9.00 XAarzm s$ So OSS PUSCUS arian cothih a eemeetne nom Goednear cer eee aut a: lgramgv 3.25 Xasgy re Chlorides ohn). heehee ee eee Seen peek 1 oz. cb 100° Xataj Vanillin, U.S. P., refined....................... Merck White Label 1 oz. tin .80 Xatog Varnish, for filling in graduation marks on etched stem thermometers... 0.065 bh 6 ee Re ee eed crn es 1 oz. cb 50 Xatzk is Gopalice cise Beet ieee Poe a era Genie Rane Meena ncaa Ue e 100 gram cb 35 Xauis Veal, Dehydrated). ao 2eciahed ecg aoe etaemaann Difco 8 oz. cb 2.70 Xauof 1 Ib. cb 5.25 Xauut Verdigris, see COPPER ACETATE.............0 0 cece ccc ee ee Vermillion, see MERCURY SULFIDE RED..... ................... Vesuvine, see BISMARK BROWN............. 0 2... cece eee Vulcan Paste Refractory Cement, see CEMENT... ................... Washing Soda, see SODIUM CARBONATE..... ................5.. Water Blue: see-ANILINE BLUE ce estates bidet a eater HEU OS! erie ten, cogpnee 13 Artery Forceps................. 226 “Scissors, Coronary........ 230 Asbestos Block for Sodium Lamp.. 553 BOATS nen Gunves et ocean 13 i COMMON titers csc Gaews Bees 112 : @ordieh eR iesh ate toe 13 : GIOVESHS trent Sense 13 os Wiatst ates as a smpatok 14 Y EDGR Rberrechirt nhs incl Rau Sos 14 7 Pak Sih eas heat oy, gente cae 14 ie IRVIN Oate yore ts eens sae 18 oy Sheet, Barrett.......... 19 = Sodium Hydrate Mixture 173 INSCATIDGhi 2 eda. wee Season ees Sonu: 173 A. & 8. Electric Ovens......464 to 466 Asphalt Flow Plate and Mould... 15 oe Road Oil and Tar Testing Apparatus: ie. 6ctss Sa: 14 to 19 a Thermometers. . . . 585 Viscosimeter............ 15 Aspirator Bottles............... ff Aspirators (Filter Pumps)........ 281 Aspirator Syringe............... 573 Assay Balances................. 57 ee Ball MEI gate cect scree 208 WS SBOAKerS kad nad oaniec cite 72 Button Brush............. 87 Bo Mas hkisis yikes radical tare 287 RIV eats rte clin aera Ae trade 9 202 oe WEG SNCS ee ec contin cool 67 A.S. T. M. Apparatus for road ma- terials and creosote oils... .. 17 to 19 A. 5S. T. M. Fire Tester.......... 452 2 A R mle H U R H T H O M A S Cc O M P A N Y Page Page Page Atlas Gooch Crucible............ 198 Balances, Torsion Cream ........ 434 Benedict-Bock Colorimeter....... 159 Atomic Models evs :< eto eanees a 435 Moisture....... 63 ““ -Lewis Sugar Tube...... 147 Atwater Desiccator.............. 219 PTUs eevee eeteseerakah eae 60, 61 5 Metabolism Outfit...... 868 Audio Oscillator: acc vscwattied. 180 Triple Beam, 3.554.050 64 Benzene Burner................. 102 Autenrieth-Koenigsberger Colori- Tropical Sugar......... 60 Benzol Testing Apparatus..... 17 to 19 MOE aheenot 5 as eae Re 159 Weights ane Ao ey tae 65 to 68 “and Toluol Thermometers. 18 Autoclaves, Bacteriological. ...37, 38 Assay . 67 Berkefeld Filter Cylinders........ 272 Chemicals se. ce 63 20 Avoirdupois. . 68 Berzelius Blowpipe.............. 75 Auto-Collimation Spectroscope... 548 Button s.4525% 67 -Pepys Gas Holder...... 332 Automatic Burettes............. 94 Fractionals..... 66 Beutel Burette Float............ 94 Pipetteses 2:4 ic. wees 4 492 Metric......... 68 Bibulous Filter Paper............ 279 Shutter. we ners yr ehCO Normal Sugar.. 67 Biesterfeld-Rohrig Fat Extraction Auxiliary Air Pump, G. E. Two ‘f Troy Prescription 68 STAID GY cas. astes Boe ee RA GO 434 Stage wa sane hereto 2 Ball ae Ring Melting Point Appa- Binding Posts .2% os 2 econo exes 70 io Condenser.........¢ 399, 402 TED CU Sie eae h eect tin ee tind comet te 19 Binocular Magnifiers............ 363 Avoirdupois Weights............ 68 “ Mills and Accessories. ...208, 209 Microscopes. ... . 389 to 391 Ba loon Filter Cylinders. . has HOU Biological Colorimeters. . .156, 157 B HlAskS rages ene aust renes ons 284 Refrigerators.......... 46 a Gas Weighing........... 325 Biram ee (Airmeter) . 9 gan cBallsesSte@el 3 tects aaron ae doe gene 208 Bitumen Crucible... . , 198 Dahetek cone sea me Balopticons and Accessories.510 to 513 . Holder, Draper Model... 15 Milk Denver cintnwenes 433 Balsam Bottles............-+.-. 79 Bladders, Animal ULSD ashe et 74 “ “ TGarere. oe 431. 432 Band Tubing, Rubber........... 535 Blair Analytical Balance ........ 50 MactsGlassware: unc: "432 433 Banta Collecting Pipette......... 492 fe OM CUhcccwnts abeuls seca hwol tench Rip ea ys 462 «6 Thee eee ee : j27 Barcroft and Roberts Blood Gas ““ Phosphorus Reductor ...475, 517 Bacteria Collector. Vacuum. ..... 604 APPA ACS... scien ance dh p whet 149 i Stirring Apparatus......... 557 Counting Apparatus Barkometers (Hydrometers)... 349 : Water Baten. ici penewanc: 610 193. 194, 195 Barnes Dissecting Microscope.... 395 Blaivas-Gradwohl Blood Sugar Guinevere 207 to 209 “Dropping Bottles. . ee SO) PIM Gein Ms Peta ieee eee ack has 147 “ Gata ar cen aa 993 Barnstead Distilling Apparatus. 934° “Blake. Bottles 2.24 2: s.cdiee ain eae a 213 Bacteriological Apparatus....21 to 46 Barometer, Aneroid........... 69, 452 Blast Burners............. 100 to 102 Counting Chamber 138 ; BUNS OI. sissies goss, eons 69 “ Furnaces, Fletcher......... 309 Halter ee ae 279 a Observatory......... 69 Blocks, Absorption reset lees Ged 1 Mailing Case... .. 363 ts Las tts center tanta . 69 ms Embedding.............. 74 : Pipettes iieeket bela 489 = a . ae ree seas 337 Blood een ef Maya i cy A arre ompany Apparatus for oagulation Time Apparatus 14: Badger eeee Eubane ane 448 Testing Tars, Pitches, Oil and “Collector, Keidel Vacuum.. 151 Bagasse Cutters................ 207 Benzols vei ucen slang thes 17 to e ‘Counting Apparatus....... 1387 v Digester, Rotary........ 221 Basins Acid 95. ek) vernon Ae tts “ SA ee 151 “ Disintegrator........... 207 Basket, Bronze, Wayte.......... 130 “ Diluting Pipettes.......... 141 Baier Phermomisrer cae on - 520 ‘Perforated, Centrifuge 121, 125 “Gas Apparatus............ 149 Bailey Crucible Holder.......... 201 ‘Porcelain, International... 130 to WAN CCS iici crassa stn: 151 ““” Hydrogen Electrode....... 250 y Test MU UTID Oise an Cotcersecnicteg Rete aint Bit Letting Needle ay haat oe tes 1515572 “Myers Blood Sugar Tube... 147 Bates Polariscope Tubes......... 506 ‘Pipette, Wrightsscicca esac 151 “Walker Extraction Appara- Sugar Plasksie. ss sasnaizgac av 297 Plasma, Alkali Reserve Outfit 144 Ana mp be eee iy ease ne 269 Baths, Constant Temperature . 186, 187 Pressure Recording Capsule, Bakelite Holder for Haemacytome- Bath, Dye, Matthews........... 239 ran gets ccichs wales eet ace 150 ter slided a pabse Sante emcee 140 Rectangular......... 240" Sugar Tubes.......... 147, 577 Balances Tinea Ee tO 47 to 64 Baths, Inactivating..... 40 to 43, 610 “Surface Tension Apparatus. 143 iNGininti eee 57 Incubatinigrs sc2..ccpea5.3 40 to 43 ‘Tube, for Centrifuge. . 118 “ Vr ial ee pate pe eae 9 “ Paraffine Embedding .40, 42, 43 “Urea “Apparatus, Marshall.. 148 SN Sane one re 57 oy SAN cat ees beeen 536 “and Urine Chemistry Appa- ‘ EAD Galatea he eT e Serological............ 40 to 43 ratus..... 146 to 149 “ Centrifuge Tube. 118, 129 Wiatterenitns sc ink cs kon 609 to 616 ss “Pipettes. ....... 491 “ Ghain oration oh ns ane: 56 Battery Binding Posts........... 70 : ee Apparatus. . 148 “ Gta ree ees 61 Connectors............. 70 Blount Gas Absorption Tube..... 826 “ Cove ees 68 5 Dryeeeis sate tas aos back 69 Blowers, Foot-power............ 74 “ Dispensing. . 61 2 VATS coccstcd 5 ok 2a ist Seashore 70 fe and Rotary Air Pump, 3 “ Edwards Gas ‘Density... 328 Storage: jagiag Messeiits eee 69), “BIOW PIPES. onesie due ce rten ce! TA, “5 re Pails bowen at tees ¢4 Baume Hydrometers....... 346 to 350 Blowpipe Charcoal............... 75 “ Harvard Trip.......... G0e Beads; Glasses ke canoes 335 a a ete Pee A eT ee 74 “ Jolly Spiral Spring... ... 63 Beakers, ATUMINDIMN ses acee as 43 70 i Set, Butler. . ee “ Laboratory.......... 57, 59 . Brushes eae cond broad 86 to 88 Tips ahs Cae 74, 75 “ Téeture Table: 5. 68. 59 i Clamps, Chaddock...... 134 : “for burners........ 100 tM ISTUTOR ee nok ee es 61 COpDeieistn smcmte ash al 70 to) (AOOlORIGAl thie feo echoes 226 “ Davee teeta ae - 68 ‘i GUASS ents Sacer s 71,72 Blue Flame Burners............. 99 es Prescription......... 58, 61 ‘ Porcelain e scatiscs ete casted 70 “ Glass Goggles.............. 338 “ Balpeoy ies eee 60 Refractometer.......... 521 Bly Camera Lucida.............. 400 ies erent ie fy Oke Se we ed 68 Soe SIL IC pet ieee ea 72 Boards, Animal................. 9 “ Riders. 66 ‘ SU alien ehee, Meta aetosh ape 2 ‘i ASDEStOS give he oc eck eae 13 « Riobervahls: ea vee. 60 Beckmann Molecular Weight De- =~ SBuekingy. 2s ol uets eco: 201 SGlUt Once eee one 61 termination Apparatus 436 Boats, Combustion. . 174 “ “ Metric........ 3 ay Thermometers........ 586 Bock-Benedict Colorimeter. . 159 Specific Gravity, Chaino- Beebe & Buxton Drying Apparatus 239 Bogert Distilling Receiver........ 238 matic.63,64 Bell Glasses................... 73,74 Bohr Gas Meter................ 332 se ee Precision: 63° | oars. es nts ales pers 73, 74 Boilers, or Saucepans............ 5 “ “ “ Westphal 63 Belts, Carborundum Grinding.... 878 Boiling Flasks................. 283 He Parnes School...... 58 Bending Rod, Glass............. 337 “Point Apparatus..... 436, 437 e Torsion. . a 62 e Tubing, Glass.......... 836 ‘Thermometers. . 589 A R T H U R H ‘le H O M A S Ce O M P A N Y Page Page Page Bolting:Cloth.x..0¢. ¢secee2Baee is SB OX LAM Gezne cadens tne Ge Steo ahs eed 86 Burette Floats................. 94 Ye St) ADISCS) kn uaese As 2 617 POE WOOG ss. 3 have, Bea &. aeven oles worn 86 fo Folin Sugar Titration... 491 Bomb Calorimeter, Parr Oxygen 107 Boyce Adjustable Burner........ 98 re Wunnelee. coca oaths 94 ie ee ““ Peroxide 106 Brain Knife.................... 227 Ye GAS es aan eoay lpn Natriss Game etre 326 Emerson Single Valve..... 109 Branch Tubes.................. 602 os ““ Tutwiler, for H,S... 325 Parr Oxygen............. 107 Brass Condensers............... 178 Ge Hostetter and Roberts... 93 Parr Peroxide............ 106 By MOWAT se aky rate Manet ances eer a 618 i Krauss-Washburn...... 93 Parr Sulphur......... 561, 563 ei “Gauze. . ict eon OLD) ae Meniscus Reader....... 94 ‘“ Riche Calorimeter........ 111 Braun Electrolytic Outfit........ 242 ‘s Morse Calibrating...... 93 Bone Ash Cupels................ 214 “Sample Grinders..... 203 to 205 : Pane ds rs certain A 90, 262 Cutting Forceps........... 226 Breaker, Circuit . : Bien TOO he Schellbach............. 91 Sey EGA War taraee Tat ome he _.. 228 Breed & Brew Counting Apparatus 195 i Squibb Zero........... 94 Boothby Flutter Valve.......... 367 Bridge, Half Meter............. 182 a StOPCOCh 83 seen ngs aoe ey 93 ‘* -Sandiford Gas Analysis i" Slide Wires. cc4 cases. 181 mi Supports.............95, 96 ADPAFALUS & hos ta a eee 324 ‘* Wheatstone............. 181 a MEFAtIN ES a ii44 ies acetals 93 Books, Label................ 359, 360 ““ Measuring.......... 181, 182 is Weighing....... 93, 259 Boot Specific Gravity Bottle...... 544 “Salt (Glass Tubes)....... 251 Biirker School Spectroscope...... 546 Borers; @ork: i205 tegen ; 192, 193 Brinnell Microscope............. $89 Burnersi.2. 23-222 ken Need 96 to 105 Boston Slide Forceps............ 300 Brinton-Reischauer Specific Gravity 8°“ “A CCOSSOTICS singe sates 100 Bottles, various. 76 to 85 BOttlen ee tear ae ee 544 SS Aeetylene so awcsec wei 98 Absorption, Fisher....... 508 Briquette Moulds. . Mere a ees) O GAD STADE oon on eos ie 97 ‘* Amber Glass............ 76 Mould Plate......... 113 “Alcohol Stove....... 104, 105 ““ Anaesthetic, Brodie...... 484 Brix Hydrometers............... 348 “ Argand. Susebases 96 SS SNSpina bOncsants on uiecetcers 78 Brodie Anaesthetic Bottle and Air “Attachments. . 100 He SBalsanne esci avn.oee eles 79 Wiariie near task bis hea cee aiane 484 S GBOAZONE Soi sashes eases es 102 “Blake Culture........... 213 Brodie Animal Table............ 11 BIAS bs cca oe sce ers 100 to 102 SBrUushestis eta nes sala 86 to 88 “Respiration Pump........ 484 i. Benzene rn is vin ads ks 102 “* Butter Test............. 482 “ -Russell-Boggs Coagulo- “BMG Mame sccncrsie saeess 99 po Ga psiaad soma: shine Meee 84 MELO SH a ten Tees De ea ee nt 143 “Bunsen... . 97 to 99 e ef Tiny Woe seccd a eced es 226 Brodie Time Marking Clock...... 480 u “Acetylene. 0 98 “ Centrifuge...........128, 129 “ .Starling Kymograph...... 476 we “Chaddock), ci. eg enue se 99 “Cream Test......... 129, 432 Bromwell Fusel Oil ne 320 “Chimneyse ccs spies ee 96 “s Gultunes oa tM aankie 76 Brown-Duvel Cylinders. . ; 215 ‘““ Dangler Gasoline........ 103 6 Dropping. 2: ichs044 jesse 79 “Condenser Tube. 178 “Detroit Adjustable...... 98 i Labelled 79 fo Plasks: iinet uacv298 ‘" Evaporating............ 102 SP RGHER. sors sions ....... 80 Briihl Distilling Receiver......... 238 “ “Risher Patent... 4.222 sas5 98 ‘Gas Generating...... 330). B38) Brushes’ cscs ye cox x ek ovate a 86 to 88 “Fletcher Radial......... 103 se Se Wiashin fej. cr es 2 OL Brass Wire............. 114 if “Solid Flame..... 103 “Glass Stoppered........ 77, 78 Biichner Anaerobic Culture ee 1GRCNMAN ra. 6h sed hs: 99 “Green Glass............. 76 Paratusiics elec ses aly 8 ‘“ Khotal Hydro-Carbon.... 104 ‘Hard Rubber........... 80 Biichner Funnels............ ... 302 “Koch Safety............ 104 “Immersion Oil.......... 80 Buck Mortar................... 438 S duow: Bormi24.0is ase ies eat 103 Milk Pest yg ese ck 8 129, 432 Bucket, Waste.................. 607 Be Mero ion bed Geapeccne 96 “Oil Sample............. 80 Bucking Boards................. 201 “Monochromatic. . . 553 ‘* Percolator. . 80, 475 Buffer Solutions and Mixtures.... 164 “ “Quadruples.s wakes eats 99 “Pipette and Acid........ 433 Bulbs, Absorption, various .. 172, 173 , eeiage for Sts ak. 17 SS MPOWED. cco-t boas hae ees 80 Bulb, Coke, A.S.T.M. and Barrett 19 . BOrms 9 30S aendo 99 MS Pressiire: 2 cs ene ke: 80 Combined Potash and ae ‘“ Scimateo Patent......... 98 “ Reagent............. 81 to 84 ing Tube, Vanier . .172, 239 Be Shield cine ead Sa a oes 18 Sicha WU ss a ek eine eo OF) Birilsion eh peg uae ccs a: 378 “ Smoking.............. 477 a Specific Gravity...... 544, 545 “Kjeldahl Connecting. . 447, 448 ‘ SDCCUION cic pan sed AS aut 553 2 “ "Barrett 17 “Teevellingel: cet can tigues: 5% 326 DEO ees Aiaieneccae oni 98 e = “« LeChate- “Mercury Chloride Iodide... 146 Tip for Gasoline Gas..... 25 Ligete ey eee ete eee, 114. ‘Meyer Sulphur............ 176 Se iP trril ets BAL Rete. 98 “Specific Gravity, Schuman 114 "© Nitrogen ...25 6 concen 448 . Tubing, flexible......... 104 fe Specimen............ 84 to 85 “Potash, various ....... 508, 563 Untversalicecs bsaoe cree’ 98 “ Sputum.........85, 129, 555 ‘* Rubber, various ....... 530, 531 Butler Blowpipe Set............. 75 “Sterilizer. .......0...... 129 “ Temperature.............. 146 ‘Handbook... .. Foden, JLo fe Vaccine ieee aie eon 85 - Wrea. Molin: weiss ce; _.. 146 Butter Refractometer............ 520 #0 “Washing: 1 scauisoe seta? 607 Bulls-eye Condenser............. 402 ") ROSt Boule eden agi ae 432 “Water Sample........... 85 Bunker Hydrogen Electrode...... 250 Button PUTS nected vena ves es 299 a Weighing........... 617, 618 Bunsen Barometer.............. 69 Weights, Assay . 67 CE Woot fla soe g nti rn oetces hee 85 Blast Burners.......100, 101 Buxton & Beebe Drying Apparatus 239 Bovie Calomel Electrode Vessel... 254 i Burners’ 22.0.8 oyun: 97 to 99 “ Hydrogen-Calomel Cell... . 254 Z “Acetylene . 98 C ve Electrode Vessel.. 254 ie Clamps eyes chee 132 “ ‘Hydrogen-ion Outfit....... 255 oe Eudiometers....... 263 Cabinet, Micro Slide............ 416 ‘‘ Potentiometer............. 254 af Ring Form Burner. . 99 ot Moist Chamber, Frost’s. 195 Bowen Potash Bulb............. 508 Bunte Gas Burette.............. 326 Calcium Chloride Baths, Dye.... 239 Bowl, Sharples Centrifuge........ [Bl VsBUPCUbOS ace h cen ined anes rg 89 to 94 vs Cylinders... . 105 Box, Filter ADEP Ss genet tecicon eh 280 8 Accessories............ 94 as Drying Tube... 105 Slide, corrugated........... 19 oe ACI cnrig acenn one A in 4382 “ es Tubes......... 105 “ Culture Dish........... Qld 2 oe Amber Glass........... 90 Calculator, Hydrogen-ion........ 251 “* Embedding................ 263 v Attachments........... 94 Caldwell Crucibles........... 198, 199 “Micro Slide. ..........0.+.2.4.- 415 3 Automatic............. 94 Calibrating Burettes........ 93 €"Pasteboard 4.x.) ¢cccdd koe get 86 aS Brushesee nite: GS nhs eae 88 oh Pipettes: ssc seeccn ne. 492 SE PipettCrsnciis meee meee 494 a CGE Opa ect bach nists rei eer ge te 94 Calipers, various................ 365 “ Resistance, Electric. .... 182, 245 cs Certified . 92° “Galiper Rules. oy 9 edad een on 364 “ Staining. 556 a Clamps and Holders. 133, 136 oe DLIMOR sect euacacey ine) Seuss hs 365 3 A R T H U R H T H OF M AS Cc Oo M P A N Y Page Page Page Calomel Electrode Vessels. .248 to 251 Cells, Hydrogen-Calomel, Bovie... 255 Clamps, Mohr Pinchcock........ 135 ‘ Hydrogen Cell, Bovie.... 255 Liquid, Interference Refrac- Miuscléivce seine ae: 483 Calorimeters and accessories, 106 to 111 , tometer... 6... 526 x Novy Anaerobic Culture Calorimeter Scales. . : rae LO . Micro Slide... ... eves 416 Apparatus .... 8 “ Thermometers 106,107, 109 POPOUS: 3 yeaie aad Sac iteee dees 214 a Object......... 424, 425, 428 110, 111, 587 oe. Stan dard e.2 ta eater alee a 247 i Ostwald vices ace esse ess 132 Camel Hair Brushes............. 87 “ Tintometer «os acess ot es 162 se Recording Apparatus.... 135 Ramcilsisecees cock eck 87 Cement, Alundum Refractory.... 112 i Right-Angle............ 135 Camera Lucidas................ 400 Asbestos... ........... 112 ‘Rubber Tubing......... 135 “ Metallographie. . ..372 to 374 : deKhotinsky........... 112 “Slow Motion........ 135, 479 “ Micro-photographic 418 to 423 ‘ Northrup Refractory.... 112 : SPINe.o44cecen aan het 140 es Nessler Color Tube...... 152 PaMinis diggs peas eucsenies 114 Stoddart............++- 134 Spectrographic..... 550, 552 is Sampler.............-. 113 “Tilting Knife........_.. 428 Camp Shaking Apparatus........ 538 . SCV eSsn ccs seme ignea 540 . Tubulation......... 466, 597 Campbell-Kennicott-Hurley Colori- ? Steaming Apparatus.... 114 Universal..... 132, 133 meter. _ 153 a Testing Apparatus. .113, 114 is Watch Glass............ 134 Candles, Turbidimeter. - 603 Cenco Electric Heater........... 341 ‘* Wire Connection........ 136 Cane Mills, Sugar. . _ 207 Hyvac Air Pump......... 3 Clark Color Comparator......... 165 Gamulaetn. Ge ted _.. 485 “Rotary Air Pump and s Connecting Bulloe cc sea conens 447 Capillary Diluting Pipette, New- BOWER hcntcre ne ne sce. pao 3 Vessel. ........ 250 comer . _ 157 Centrifugals, International....... 130 “Hydrogen Electrode Vessel. 250 Electrometer, ‘Eppley . . 246 BYE eis 4 Sens 130 “ & Lubs Indicators......... 163 Tubes.... 246 Centrifuges and accessories..115 to 131 Clay Combustion Boats. . . 174 Pipette............1438, 157 Baskets, perforated. . 130 CUD ESS» tere seas 176 “Breed & Brew... 195 a Electric B. & L.. 116 =©‘‘ Crucibles. . ; ges 199 “Newcomer. . 143, 157 rc “International . “Gutters for Furnaces........ 310 PUbineesachise iene baa 337 119 to 122 “ Muffles. . Stina pets CASO ue “Silica 541 * Glassware......118 to 129“ Tiles for Furnaces.......... 310 Cap, Alundum Filter. 18 i CAC c's ckete cater tpeet 3 115 Cleveland Open Testers. . 451 ‘Bottle, Glass. . 84 i Hookworm Outfit.... 115 Clinical and Diagnostic Apparatus Burette NO Stee A ty tee ee 94 a Outfit, Board of Health 137 to 151 tee SRATD DOR nn claoeecs. ao eis 531 120, 122 i Microtomes. . .423, 424 Capsules, Blood, Wright. 151 oe Outfit, Hospital...119, 122 Clippings, Filter Paper.. fret) HAO: Combustion 175 a Sharples Genesee Sie Scena 131 Clock, Time Marking, Brodie... . 480 ce Erlanger . oo... 150 i Shelton Electric...... 117 ‘Victor Interval Timer..... 151 “ Expanding............ 597 se Tube Balance... aoe 129 ““ Wizard Interval Timer.... 151 co if A. &S...... 466 as Water Motor.. te: 116 Closed Flash Point Tester... . 452 “ Expansion, Serological Chaddock Burette Support. . 95 Closet, Freezing................. 46 Ba thitite seat oc eee Al Burner and accessories. 99 Cloth; Mimery seit heehee aie sors 263 “ Hearson Patent Expan- a Clamps. ha: cartes 134 ‘Polishing. . . 376 SION cs ds ee an 25, 41,45 Chainomatic Balances........... 56 CO, Apparatus, Fredericia....... 149 “ Hofmeister........... 112 Chains and Hooks.............. 227 Van Slyke....... 149 “ Sugar.............0.. 996 Chalet Colorimeter Lamp ....... 159 “ Cylinders.................. 327 GaTWOnSins no ko ios kh ean 112 ei Micro Lamp............- 411 Coagulation Time Apparatus..... 143 “ Brushes........... 120, 124 Chamberland-Pasteur Filter Appa- Coadgulators ye: 3M eM wo. ame es 33 as Cored and Solid........ 376 ratus.... 273 Coagulometer, Brodie- Russel l- Carbon Dioxide Apparatus....... 149 sf ss Filter Cylin- BOGGS cil ecdnne hice evi ots Aa oes 143 Carbon Lamp, Incubator........ 29 ; COTS a gsc 272 Coal Grinders, Braun........ 2038, 204 “ Monoxide Apparatus..... 149 Chambers, Counting, Haemacytom- “Tar Distillation Flasks...... 288 Carbon Residue Outfit, Conradson 455 ” eter........... 137 to 141 “ “ Testing Apparatus, Bar- Carbonate Apparatus, Van Slyke.. 149 és WMioist yee eis eae 211 TOG reese tah neoas hee 17 to 19 Carbonic Acid Determination a ‘Vacuum Oven........ 470 Cobalt Bottle 5 tcennunte ae tye As 79 paratus (Alkalimeters). a 7 Chapman Filter Pumps.......... 281 Coddington Magnifiers........... 361 -\ Carborundum Grinding Belts. 378 Charcoal, Blowpipe............. 75 Coils, Induction................. 351 Carboy Inclinator, Universal. .... 112 Chardin Filter Paper............ 279 . RGSISLANCER sins pene a ee eee 528 Cardiograph Attachment, Jaquet. 150 Chemical Labels................ 360 Coke Bulb, A.S.T.M. and Barrett. 19 Cardioid Condenser, Siedentopf... 398 A Microscope............ 888 Cold Closets.................... 46 Carius Tube Furnace............ 311 Chimneys, Burner............ 96, 100 Collar, Asphalt Viscosimeter..... 15 Carmick-Hubbard Specific Gravity Chipmunk Crushers, Braun...... 205 Collecting Pipette................ 492 Bort Ga hee bat rane wer ae: 545 Chopper, Meat..............206, 366 Collector, Bacteria Vacuum...... 604 Carrier, Absorption Tube. . 550 Chopping Apparatus....... 201 to 209 ie Blood, Keidel Vacuum.. 151 «~~ " Culture Dish. . 211 Chromel Crucible Tongs......... 597 Collimator Tube Attachment, Hil- Carrying Case and ‘Incubator, _ Wrian gles ss cc cows arte sts 600 OP ern Hee tet hear ge ree He 550 Goh een eat ee a 195 ‘ Wire a etre eee ae 443, 619 Color Comparators.......... 165, 166 Cartilage TKI OSs & ee wrens cheek 227 Gauze wnicece aint 619 ““ Comparison Tubes...... 152 Gieins -adetic se aek. 230 Chromometer, Saybolt Universal.. 161 “Standards, LaMotte....... 165 Cases, Counting Chamber....... 141 Chronometer, Jaquet Graphic.... 480 “ TubeCamera............. 152 “Dissecting Instrument... . 231 Circuit Breaker............. 466, 597 me Supports SW ai ere es 152 ““ Haemacytometer......... 141 Claisen Distillation Flask........ 289 Colored Glass Rod............. 337 fe Jeffer...... 194 156, 158 i of Electrolytes 179 to 190 me s Little Plate Nutting.........160, 161 a Outfits.......187 to 190 Method..... 195 Plungers......155 to 157 a Titration Outfit.... 190 Es nS Stewart.. 193 Schreiner........... 153 ie Water Distilling Ap- i Wolffhuegel . 194 Stammer........... 162 PALA CUS: secre vases 237 BS seas. Frost Ruling. .... 194 Trough. . ...... 159 Cones, Filter, Alundum..... OTs Gell; Waters. 26. ccje.0 617 Tubes, Myers. Sena ete 160 Us ADELA Wise erence 278 a Chambers, Haemacyto- a Wedge.......... 159 i “ Platinum.......... 497 meter .137 to 141 Colorimetric epee He for det. of HOP Tani O Mla = cmagiee ee hese 23d LOT ae * Hausser Inter- H-ion cone....163 to 166 “ Measuring............... 365 changeable ee Indicators ...... 163, 164 ‘© Support, Imhoff.......... 191 137 to 141 Outfit, Levy, Rown- Connecting Adapters............ 1 e Levy. .137 to 141 tree & Marriott ..... 144 Bulbs, Kjeldahl... 447, 448 si Glassiis se a Sales 194 Columbia-Hopkins Museum Jars.. 354 “ Tube, A.S.T.M. and Couplings, Filter Pump.......... 281 Combustion Apparatus... .167 to 176 Barrette Gvies enesaw ens 7s: Covers, Berl CC aren shseue tecieinesh aces 68 IB Oats ec ehecukn eee 174 oF Tube, Fume......... 146 Culture Dish. . 210 f Boat Linings........ 174 “~’ Gas Burette.... 326 Cover Glasses, Haemacytometer. . 141 s Shields....... 174 ss 607 SiliCaer syed LOU Howard Counting ee Capsules........... 175 ee Wessels soo ns nats 250 Chamber......... 194 “ Furnaces....... ... 810 Connection Wire, Electrical...... 619 i pe AM Cron as Sr nee . 413 e as Fletcher... 309 Connectors, Air Pump. Bea NG 558, 559 Bs ‘““ Polariscope....... 506 rs Periscope, Smith- Battery. . feo S00 ie ‘* Reinforced Precision 141 Rudy, oe ovine an 175 fe HOS sc. sien 2, Bee a 559 Cover Guard, Centrifuge........ 116 ee Spoon, Parker. . 218 ee Rubber............ 603 “Ship, Whipple............ 617 “ Train, Fleming. 168 to 170 Conradson Carbon Residue Outfit. 455 “Glass Forceps............ 299 Combustion Train, Stetser and Constant Speed MOtor®. psecsccn es 440 Cover’s Goggles................. 338 Norton...170, 171 “Generator. 180 Crampton-Spencer Sugar Pipettes. 493 aS «Vanier... .167, 168 oe Temperature Baths. .186, 187 Cream Pipette, Babcock......... 433 ‘x EU GS 335 eels et 175, 176 es Outfit, Re. “Test Bottles......... He 432 oe Tube Furnace, Hos- se fractometer............ 523 Creosote Flask............. .. 289 kins ......... 313 Constant Temperature Water Baths 616 ‘‘ Retort, Pyrex Glass..... 19 ee “Furnace, Mul- Contact Ki Gy chants hen bees cere 191 Crowell Rotary Air Pumps. . 4,5 tiple Unit...... 316, 317 ‘“ DuBois-Reymond... 485 Crucibles and Covers. . 196 to 200 i TPUbDING 2 one ea BOL a Mercury. ccs isdn eek 566 “~ Procelain 197, 198 Commutator, Mercury........... 485 Control Plates, Quartz... . 506 “ Alundum..... .196, 199 Comparators, Color.......... 165, 166 “Tube, Jellett Telescopic. . 506 i Bitumen.......... le, 198 Comparison Spectroscope........ 546 Cooledge Color Comparator...... 166 » Caldwell i: s2..4 4225 198, 199 se Tubes, Color........ 152 Cooling Cell, DeKhotinsky Water Oe UCLA yeah es Mae kia tee .196, 199 Compartment Incubators. ciseiien JZ Bat ited ase Baten eNO Ea ce 615 % COpPel csi aes ka es 200 Tray, Paraffine. . 43 Coordinate Paper............... 254 “Filtering. 199 Compensating Oculars, B & Tis: 3896 Coplin Staining Jar.............. 556 a Furnaces, Fletcher 307 to 309 “ Zeiss..... 407 Copper Beakers................ 10 oe Hoskins...... 312 Composite Cupels............... 214 Crucibles and Covers.... 200 x be Multiple Unit. 314 Compression Surfaces, Porcelain... 510 a Cup, Barrett............ 18 os Gooch........... 197 to 199 Compressors, Screw............. 135 “Determination Flask..... 287 6 “Atlas Modification 198 Concentric Rings............... 529 ge Elackastssger ee tae 287 ‘i Ho MINICKOL & sacle cert ae 200 Condensation Air Pump, Langmuir 2 fs Retorts................ 527 i “Porcelain. . ..197, 198 Condensers, VATIOUSi coos feted Lie. 28 ee Rings, Concentric. 529 a TSUN Cane sects Agden 199 BRITE kgs oe aes ENS 182 a Stills, A.S.T.M. and Barrett 17 me Holders. .....184, 201 i Auxiliary........3899, 402 ee Wile ene a oe 618 ROMS parsers nema oee dearer & 200 s Brass eb ioe tes env asker 178° Cord: Asbestos: a: 37 cabt ete ens 4 13 AK AWINS ota t yisls 8 eciade 200 es Bulls-eye........... AO aC Orie ek eee ee 191, 192 i Niekél. 5 s.6 cuss cnc dais 200 oe Cylinder........... 18 Cork Borers................ 192, 193 “ Pennock-Martin........ 200 fe Distilling Apparatus. 236 “Borer Sharpener........... 193 “ Platinum..........:... 497 “s Extraction.. 266 “Press, Rotary............. 193 . Plumbago............. 196 fe Jacket, A.S.T.M. and ie SRubberssstnaian scare: 532, 533 ‘“ Poreelain .......... 197, 198 Barrett eich wae RISER 18 ELC COW cite ee Cite ns 193 a FROSCH inne ante se es ey 198 e Knorr Extraction.... 265 Cornet Cover Glass Forceps...... 300 bee SiC ans Saar Sega nt es 199 a Substage........... 897 Coronary Artery Scissors......... 230 i Silvers cama ation nau tnt 200 se Supports........... 178 Corrugated Slide Box............ 19 Skidmore.............. 200 is Tubes ja cahesdink 146, 177 Cots, Finger.................... 531 See. STONES aca senses eens 597 : “ AS.T.M. and Cottle Extraction Apparatus. . 266 Crushers epee He teks Bee Se ayo ar hy 201 Barrett............. a « Flask 290 Braun conus a aha wh 205 os Tubes, Barrett........ 19 Gite nnd Qi] Pinette 2 a implex......... 204 Ss ““ " Brown-Duvel. 178 Cottonseed OW Bes acetal a vi “. “Case: Patents ov ida. r 202 s Trough, A.S.T.M. and A re Crushing Apparatus....... 201 to 209 Barretti: wane tanctaes 17 Cottrell Boiling Point Apparatus.. 437 Cryoscopes..................... 209 “ Ultra-Microscope Counter Balance: oi.050523 Sei cee 61 es Hortvet Milk........ 434 Cardioid............ 398 Hand, Veeder........... 193 Thermometers 209, 434, 587 “ Vacuum Distilling Ap- Counterpoised Scoops........... 226 Crystal Models................. 435 Paratuss Bottle. ae 307 ee dumm Chiggic... 10 tae Boe araday Washing Bottle......... ne ae Embedding Ee Paraffine.... . "42, 43 Fat Extraction Tubes. . 434 io Silenavie Atal: a a hae Pua eH a oes Fermentation Saccharometer, Ein- Vanier..........176, 239 me AOuenss Bac eee 0 Pee ee ae a ee oc a Ovens, Paraffine 44, Z . SUES eee 7 270 ae a Zine, Vanier. ... .176, 239 Hi WS ie ores oe 45 “ ae See ‘e 570 u ois- ey mond Contact Key.. 485 Embryological Wa ‘ch Glas SSeS... .. Ee ; Inductorium. 483 Tiersen Fuel ee ae Se ea os re Duboscq- Pellin Colorimeters 155 to 157 Emery Cloth 2 dies Paned ine Blocks soar ign LG ee ee aa Tab oe eine i oe Field Incubators. pees . 30 ee ee firatbeio pe Si Mien aA SA tei me REID 3 Fieldner Furnace, ‘Hoskins . 314 Ductility Machine, Smith........ 15 ye Stand. 7 ae aa oe cha ie oe et udley iscosity Pipette......... 455 Enamelware Casseroles.......... Vs ache eet a Dujardin-Salleron Bpaliomeer vt pene Cant ae ale Bilan Mignomeber- Cawars ae Dulin Rotarex.................. 16 oe Funnel ae a ee oe Dumas-Pratt Filter Paper... beate a Gradeat ea ee coe eterna ore a eee er nies ona Dunham Fermentation Tubes. . 270 ms Sauc ee a uae - Eiline ee a ion oo es s ee Saal sana tne, Beta to i Attachment for tubes, flasks 214 too oe 148 ee eee en eae ee uNoiiy Surface Tension Apparatus 568 28 Prep eee ane etd gE Duplex Slide Rule....... i ‘ ie 542 peer eae cena a tf Ee in ea pe Duvel-Brown Cvlinde iSveerdee oa Engraver’s Glass (Magnifier) _ 363 Cylinders 272 < y ee : oes : . ne 272 oo eee | ne e sas aoe a 5 ee Pes f bee. . ; atinum Es Dyo Baia aaitete: cc aa eae Mbemgweensmeta 18) Be aland ma Rectangular Beh ee Ss 240 Erlenmeyer Flasks 285, 2 3 ee pe ae eo POts: Classis. ise See tects 72 Esmarch Culture ‘Dishes. . : cin ey i ee 300 0 Re eee ni Se Re i AS ma arant creer Ae eae 332 p n 70 tee Sampling Ap- ee ““ Mantles, Glass...... ee Ae E ieee USS seo$ sists eee tas os Filter Paper... pee 275 to 280 Budiometers, is pert s oF % DOr Ae ace Mesa 279 Ear Tags for animals............ 11 ee cere ao a S Bio per eaaa 380 Earthenware Culture Dish Covers 210 zs Ure, cee - 263 as s CGhaidi Bre Pl atesk-aeheeeen: 495 Evaporating Burners........ 102 6 = Clipt ee a Bbulliometers:. 2.:<) scsiae saad sees 240 Dish Clamp, Chad- % a C eee ee ong Ebulliometer Thermometers.. .240, 588 dock... 134 . DnB ction... a. Edwards Gas Density Balance.... 328 re 8 BSS pa occ - 224 se _ Pratt os ore 56 Eggertz Color Comparison Tubes.. 152 “Nickel. “T9 ae “ Pul ee a Ehrlich Coe Glass Foreceps..... 299 Porcelain. 222, 223 im ne Strips a Oe tie thesa aoe neee ores 490 i © “Silica... 2282 Bis ee Sus weer ah ie 0 et ior Fermentation Saccharo- Expanding Cae aaa = 597 Poe et aera cies ed cit 280 Bhotn es Ee: Ht ree ee “Pumps... ee Electric Heaters........... 340 to 342 Patent... ok oe 41, 45 io pe eon "423 353 a Se eran Oe puppets 25, 41, c AY sens eee aioe tena He Hot Pies aise 343, 344 Glanie Helaoe doe tee 136 a Tule eee 282 : pac aton sn ei Extraction ene atS ee een to an Filtering Pe Serum...... 273 HS NO VENS ewig caesar 464 to 469 = “Fermentation 266 es Flocke seat 90; ma Me OB alengida es ana saundek 32 5 “Knorr 265 Findlay Transference Apparat eae ss Thermo-Regulators...... 595 : “— Soxhlet...... 265 Fin eG ts, Bubher es a a ame Markers........... 481 ; “'Thorn....... 266 2 Mechanical. ee a a GL Ace (al soe tia ee 619 : “Tomato Pulp. 266 Fire Clay Annealing Cups....... Electrode Adapter.............. 250 Gee ee oe ai oe Dee ee 30 Calomel . .248 to 251 a Cylinder Wiley-Rich- “ Scorifiers............. ae : Hydrogen. Net yes 248 to 251 ardson...... 266 UE eee ner Laon ee 151 ‘ Physiological.......... 485 Flasks, various... 263. 9 Fish Jars, or Aquaria...........1 ef Platinum.....242, 250, 497 “ Heat ae oe Fisher Ab i B ttle... a a Shaker and Support.... 251 “ “ a pneae i Patent cee ee "Or a Suet se Valata wien 208 : a Sir ere re % ssels cos ae ies ie ae bit Sapere Ce aa 267 Flash Point fon BAe aed awe 452 : i ea ose ti ged Weak Bathe S68 Flasks, a ester Thermometers 588 Electrolytic Condudarity Appara- ‘“ Syphon Tubes........ 266 A os eee see ger ok ene eer 179 to 190 o Gti cee | ae en ms Gat Se roy 249 i Tubes. ped . Alkalinity . Se teh Tacebe RIES 298 ie SeOrs . “oat, 567 As oo ae one ca ont Nitrogen Distilla- “Switchboard... . Bal, 242 et pe Wa ie ee eis ne a Electrometer, Capillary, Eppley... 246 it ene Labora- i Assay. oo see 287 Pubes, Capillaty.... 246 geo dsce eas 16 Bacteria Grinder......... 207 Electrometric Apparatus for det. of EDIECES ee omb. . 395, 396 HS (Balloons soscuus cores a 284 H-ion conc.. .243 to 260 ; ISS... 407 “Bates Sugar............. 297 i Titration Outtit, Eyepiece, High Power, Spectro- ““ Brown-Duvel......... 293 Kelley sc ha aass 262 IMECER a Sianscantoe nai 550 “ Brushes......... 86 to 88 Titration Outfit, 3 Shutter...........548, 550 cha ane ree. 298 Hostteter & Roberts 259 a Stereoscopic.......... 392 & SiGareined ts . vaaiecsnen aes OO 7 A R aL H U R Hs T H O M A Ss Cc Oo M P A N Y Page Page Page Flasks, Claisen Distillation... .... 289 Folin Digestion Tube......... 147, 577 Funnels, Squibb ceneiO ys mene 304 Clamp, Chaddock........ 134 -Kjeldahl Distilling Appa- Stemless. . ‘ .. 301 Coal Tar Distillation...... 288 TACUS ee tome weg hems 446 ee Stops accossrmeiern tee 399 COpPelwr chee sao nas 287 “ -Ostwald Pipettes........... 147 Ns Stranes Lactic Acid..... 304 os ‘© Determination . 287 SS) “Pipettes aa eco «beeen seo 491 ee SUoar ye siaete ee eee 801 ‘Cottle Extraction. 290 “«-Wu Pipettes............... 147 a Supports...........305, 306 ‘* Creosote . Leen eke tales DOO “Receiving Tube.........147, 577 ny Tar-acid Separatory..... 19 9 OU GURE ss ausctuane she oes 76, 213 “* Sugar Titration Burette..... 491 es TIDES...) ase news anes 305 ‘Dewar Vacuum. PE Leer joy i “Urea Apparatus............ 146 os Victor-Meyer Sees eee eed 301 “Distillation. . .288, 289 Foot Power Blowers............. 74 Furnaces, various......... 307 to 319 ‘ Distilling, Pyrex ‘Glass.... 19 Force PUMPeh ee he dae BA 1 Carius Tube.......... 311 “Engler Distillation........ 288 Forceps. . ey .299, 300 — ClAV Si incieccies Ss eles Ome 310 ‘““Erlenmeyer........ .285, 286 Artery. Maer tei peee ket fee 226 se Combustion.......... 310 ‘ Extraction, various... .263, 290 ae Bone-Cutting........... 226 Ss Drattecccickeucsielnn 307 ie Barrett....... 18 a Cover Glass............ 299 ie Fieldner, Hoskins...... 314 res es Knorr 2.334428 263 m Dissecting.............. 227 AH st Fletcher Combustion... 309 a ae Siguiente 263 . SHUG ar acronis 195, 300 % “Crucible 307 to 309 BOS OP tM Aen ooo ete epee LIN 298 Forks, Tuning.................. 482 es ae Muffle....307, 309 “Filter Cylinder........... 272 Formic Acid Flasks............. 293 es Freas Tube........... 311 oS MTGOPIN Gs cca g Aa aaa 290, 291 Fractional Distillation Tubes..... 237 re Gas Assaying......... 308 ‘© Formic Acid............. 293 Weights.............. 66 a High-Temp Electric.... 318 “Gas Generating....... 330, 331 Frame Supports, Museum Jar.... 353 eS Hoskins......... 312 to 314 SS GOS ee ore eee enh eke 295 Frazer and Hoffman Gas Collecting ne “Combustion Tube 313 “Heater. . .299, 344 PRU Csi (a Pet eae nade meee ere ena 326 fe i Crucible...... 312 m “" & Hot Plate, Electric 344 Freas Automatic Constant Temper- as Muffle....... 312 ‘Hempel Distillation....... 289 ature Bath. ce. eye ones 187 Se Muffles........... 307, 309 ‘Holder, Shaking.......... 538 ‘Constant Temperature Bath 616 es oy Cl aye es Resets con 442 Ph? MLOGING 2 cla eta 291 ‘“ Dilution Pipette........... 492 Multiple Unit, .314 to 319 ‘Jackson Specific Gravity... 113 “Electric Incubators......27, 28 Be Combus- ‘Johnson Sulphur......... 293 fs ‘© Ovens............ 468 tion “J. R.I. C. Extraction..... 290 ne He Sterilizer......... 36 Tube316, 317 WS AR eld aii eke persion eae mega Tube: Furnaces... isaac 311 ie es “Crucible. 314 “Knorr Extraction......... 290 “Vacuum Ovens............ 470 i Sy “ Muffle... 315 “ Kohlrausch Sugar........ 297 ‘Water Bath.......... ane 614 . e “Organic ny U SaCtOSCH EA Phas ona ra ane: 298 Fredericia Carbon Dioxide Ap- Combus- ““ Ladenburg Distillation.... 289 Paratus son acwuwoun here ern as 149 tion..... 319 “Mercury Seal............ 290 Freezing Attachments, Micro- os Replacements, Fletcher re SIN GrIeyACids. oe oi) esac region 284 TOMES Ai ha ote een! 424, 425 307 to 309 ‘“ Phosphoric Acid.......... 298 Closet acps 34 tena cs 46 “ “ Hoskins. ..812, 313 SO WAQMATCZ 2 scone erp rausticciee etch ey 237 rs Microtomes............ 424 a “Multiple Unit. ““-Rubber Extraction .. 290 “ Point Apparatus (Cryo- 814 to 319 ““ Saponification............ 298 scopes) 209 ue Tubes, glass....... 811, 335 ““ Saybolt Viscosimeter. .298, 456 3 G m Beck- a Wiesnegg Muffle...... 309 “Shaw Filtering........... 291 mann 436 Fusel Oil Apparatus............. 320 Pe PATIL Can erowt bit crecrces Ceniita ethane 286 Fresenius Filter Tube........... 282 Fusing Rod; Glass: .o)soc nna cs nok 337 i “ Distillation......... 289 Friedrichs Condenser...... Ase aS r RY © ASO Seca weciens oss atts tg Siegeninwden ee 293 Forst Counting Card............ 194 ce we SST: SULATS fox Ge adel oes 297 ““ Gasometer Scale........... 270 He SSP aT hs ee uals VADs LOO me ) GuiderRlatekes cau 285 de ae 195 : pe OS UD AUT oars ie tc hs eo ore 289 “Micro Counting Apparatus.. 195 Cee ais a - ee Johnson......... 293 Fruehling & Schultz Desiccators.. 219 Gage Mi L Bors 411 “Sy Extraction............ 290 Fuchs-Rosenthal Counting Cham- 18 CTO AT Deedee ne i 2 “ Vacuum................. Dag iden Sse een ea 138, 194 Staining Racks............ 556 ‘““ Viscosimeter ......... 298, 459 Fuel Calorimeter, Emerson....... 108 Galvanometer, d’Arsonval........ 246 “Volumetric......... 293 to 296 Fume Absorption Tube.......... 146 Enclosed Lamp and “Water Analysis. . ... 289 Funnels, various.......... 300 to 305 Scale. ests dawn 246 Fleming Absorption Bulbs. . 2 AI? Barrett Paraffine Test... 18 i Moving Systems... 181 on Combustion Train..168 to 170 ee Buchner cite ene! 302 Portable A. C..... 181 ee Gas Washing Bottle..... 331 es Burette.. . ring wpa 94. Gang Moulds. csers cies 6 ee ns 113 Fletcher Blast Furnaces.......... 309 i Cone shaped. . ee ee 303 Gardner-Holdt Surface Tension Combustion Furnace. . 309 ie Be Walle arcesatt cache. tors 303 IMIGECE thr om eee mee ap eating, 568 “Draft Furnaces.......... 307 7" TOPPING ye: Gao tek 304 Gas Absorpti “ ‘Muffle Furnaces... 307, 309 if Enamelware........... 3020 « Analysis Apparelus,. 320 ie ee Py Radial Burners.......... 103 SS Filtering........... 301, 302 “ B thb 3 “Solid Flame Burner...... 108 Ho AM a bedh ks at sees fence 302 Bid Aba o Water Heater........... 617 Hard Rubber.......... 3802 “ ts PY, Ele sei are eeseible Shales pono docsasvtoesee 440 a Seetiee eee 308 a. a «, Diliott-Uhlig. 321 eo) UI Gee nataae lata 104, 367 = Hirsebs i ntisn ae sae ees 303°, He ee Haldane 323, 324 Win Pebbles. 2a; ans bez event 208 ‘“ Hookworm Tube....... Lig: : Morehead... 320 Floats, Burette................. 94 io Hot Water............ 303 “Newcomer... 324 Floating Thermometers.......... 588 “Lactic Acid............ 304. 3 ‘“ Orsat....820, 321 Florence Flasks.......)......... 283 = LaWall Separatory..... 304 s 9 “ Petterson- Flow Plate, Asphalt............. 15 ie Plantamour............ 303 Palmquist- Flutter Valve, Boothby.......... 367 o Porcelain.......... 302, 303 Rogers...... 825 Focussing Glasses............... 422 Powder’ -aaca noes 3801 as a “ Williams..... 322 Foil, Platinum. 66006220 ue abe 496 Ribbedis ics i shea sa 302 “ Apparatus, Blood, Barcroft and Folding Pocket Rule............ 364 - Sedgewick-Rafter....... 617 Roberts... 149 Folin Ammonia Absorption Tubes 146 u Separatory......... 308, 304 es ed “Van Slyke. 149 fe Apparatus....... 146 “s a A. 8. T. M. 4 o Differential Pres- “Blood Sugar Tube......... 147 and Barrett.. 17 sure of Blood..... 149 8 A R T H U R H. Ty H O M A S Cc O M P A N Y Page Page Page Gas Assaying Furnace........... 308 Glass Cover, Polariscope. . ... 506 H i PBUPetTES) Co o..o aoa cies cas, Goes 326 WUGTErS eat ee 335 ** Burette Connecting Tube.... 326 i? PMOGUSSIN By itchy Sarina. even: 422 Haemacytometers.... ..137 to 141 “for H.S, Tutwiler.... 325 “ Graduates.............838, 339 Haemacytometer Cases..... sae TAI Burners coe)y ec Seas oa. 96 to 104 "© “Micro Cover’. oo... ecne 413 Cover Glasses... 141 Calorimeter, Sargent Auto- SS. | Mortars 22%. < nhac s tetas 437 s Pipettes........ 141 MALICH ale Ate eas A eee 109 SPIER LALCS aus de ty epee 8 minegre tt Sess 495 as Tubing: ence en. DBO Collecting AD OS ee. sy2k se 326 rs “for cement moulds... 114 Haemaglobin Attachment, New- Cylinders.) 32 os tace so thai akcn 327 aS “opal, for spot method 165 comer......... 148, 157 “Density Balance, Edwards... 328 ee REA Siu d Nai niee Score 363, 517 3 Scale, Tallquist » JAZ Distributors........ . 38382, 559 WEY CRECOMS raises se ae es 527 Haemaglobinometer, Dare... . 142 FT CC Taek ede eal oy RE MPA ZA 332 “ — Rod..................3836, 3837 Haematokrit Blood Tube........ 118 Generating Bottles. . 330, 331 OS EG Fi ae en otis enter sours 536 Haemometer, Sahli.............. 142 ““ Generators, Johnson........ 331 “Settling, Imhoff........... 191 Haldane Gas Analysis A pparatus323, 324 a < Kipp. 331 Be SULT CT Stas met eaten eee 335 “Collecting Tube..... 326 ‘ Heating Equipment ‘for In- “ — Stopeocks............. 560, 561 Half Meter Bridge.............. 182 CUD ALOTSi ee oe ee cho ewe 21 a USWPNONS ix as ecswecaeans, S05 568 “* Shade Saccharimeters. .501 to 504 Holdersca teers ee an 176, 332 “ Tank, Freas.... 0.002.022. 187 Hallock Condenser...... ; 178 Hose Reducers............. 560 SL MORAG Hopp ies ooh eel ae heen 573 Hammers, Geologists............ 339 b (CG) opel onl Fr = el 343 *~ “Pintometer® <2 @ 202 Gaiaes 162 Hand Balance eaten AeA wee: 64 Interferometer, Brvlgieh: 526 ‘“ Tubes, for furnaces..... 311, 335 “ Centrifuges........ . 115 Lamp, Micro.. ictal ere eae, Tubing. | 3 .336, 337 “Microtome............... 425 Measuring Tubes....... 332 oe Cutters........ 335, 336 Handbook of Blowpipe Analysis, Meter Bohr Experimental . 332 ee fe Galige 25 wes eee 336 BuUClerreNy toe Ria eerie eni. ot 75 ““ Laboratory.......... 333 fee Wid tlic c tidenc iat ce iire nth 607, 608 Handles, File................... 271 “o OO Sargent ¢ ..110, 333 EERE WIOO Mi Renee ee 336 = Microtome Knife....... 429 He BPA OL ECSs icc fs Y ale een oe 334 Glazed Papelae ene erie tee eak 475 Hard Rubber Bottles............ 80 “Pressure Regulatorand Reduc- fe Polygraph ees ks uss 150 Hardness Tester............ .. 339 ing Valve, Hoke-Phoenix .176, 328 Glinsky Distilling Tubes......... 237 Hart Casein Tube........... 3 128 se Regulator hs Sh nee Mens Menuet 332 Globe, Bacteria Grinder......... 207 Harvard Staining Jar......... . 556 es Hearsone 2 hcg ess 32 Gloves, Asbestos............... 13 “Trip Balances. ... .. 60 f& “StOPGOCKS oo oko. cos A 559, 560 as Rubber................ 531 Harvey Thermo-regulator. . oan B94 sive eel LOSE ta tudieat sre ene een G pi 110 Glucose Pipettes.......... _ 493 Hastings Triplet Magnifiers...... 362 “* Tubes, Interference Refracto- Glue Tester, Alexander.......... 338 Hausser Counting Chambers .139, 140 MCCORs vree Sete he As 526 PSS COL Ge euaann cations 338 ‘st Cover Glasses.......... 141 is “Palladium, Hempel... 332 Glycerine Baths, Dye. ., 289 n Micrometer Slide....... 401 ‘* Washing Bottles............ 331 Jars. Sei aac) . 357 Heads, Centrifuge......... 115 to 125 ““ Weighing Balloon........... 325 Gockel Condensers rare aay _.... 178 Head Holder for animals......... 11 Gaskets, Emerson Bomb........ 109 Goetz Phosphorus Tube......... 128 “SS Polishing #2 28 eee Wl eae 439 - Oxygen Bomb.......... 107 Goggles, Blue Glass............. 338 “ Titrating, Hostetter and Peroxide Bomb......... 106 Cover’s Patent rte 338 FRODERUS Hausen nig casey sos 259 Gasoline Burners...........97 to 103 Gomberg Potash Bulb.. 508 Hearson Expansion Capsules 25, 41, 45 me Corrosion Test Cup..... 453 Goniometer, Penfield Application. . 338 Gas Regulator....... 32 is Distillation Outfit...... 454 Gooch Crucibles . een .197, 198 ai Incubators...... : (23, 24 : Gas Burner Tip........ 25 « “Atlas Modification 198 es Low ECR EIA In- i Gumming Test Cup.... 453 ““ Dises and Covers. 198 cubators.... eg Ob Gasometer Scale, Frost.......... 270 ss “Nickel .......... 200 “ Serological Bath.. Tiles. <45l Gasometric Determination of Ali- ne es Silica . . 199 Heaters, Electric.......... 340 to 342 phatic Amino Groups Apparatus 450 Governor, Wet Pressure... 110 re Haske eu tee eaten 299 Gauge, Glass Tubing............ 336 Graduates, Glassy ce ie: 338, 339 os “with Hot Plate... 344 Inoculating Loop......... 443 Gradwohl-Blaivas Blood Sugar Tube 147 a Munnel ic c2 Shays ase ae 303 “McLeod Vacuum......... 6 Granulating Mills............... 206 ‘ Oven, A. &S8........... 466 ““ Mercury Pressure......... 176 Graphic Chronometer, Jaquet..... 480 A Spiral, Refractometer... 523 IPI@SSULC? i. . cee ue eee 335 Grease, Centrifuge . z SCA 120, 124 oe Thermo-Regulator, Elec- RA DOT cosh oo eee a Rh ts 365 “ CPI Ch cue aad elle oan 596 Pe Stopeock............6.. 561 “ Vacuum... .. 05s 6h epee 335 G B 99 Waters) aimee tsccn mxkeeris 617 COO EW ATO cee eet See ee 335 “Greenman ae sap Moca Heating Plates, Electric......... 596 Gauze, Wire, all kinds........... 619 7 ceenlierect eedle ““ "Incubator....... 27 Gay-Lussac Specific Gravity Bottles 544 x older.............. 443 E ““ Thelco Oven..... 467 G.E.TwoStage Auxiliary AirPump 2 Thermo-Regulator. ... 594 a and Regulating Equip- Gear, Speed Reducing........... 442 Grethen Weighing Bottle........ 618 mentforIncubatingRooms 32 Geissler Alkalimeters............ 7 Grinders, Bacteria......... 207 to 209 s Units, Electric, C.S. & E. 596 a Filter Pump............ 281 rt Braun Laboratory...... 204 a “Hot Plate.....343, 344 «« -Wetzel Potash Bulb..... 508 ns “Sample.......... 203 ee ““ Incubator........ 27 Generator, Constant Speed Motor 180 2 Coal, Braun....... ae 204 ne “for Sterilizer... ... 36 eS GAS Sint ha me hcon ny eothlten wiitie 331 i. Iron Ore, Braun... .203, 204 Heidenhain Thermometer........ 436 a Set, Motor.......... 442 ne Meaty fe usass ean ea de 366 Heim Animal Cage.............. 10 Genth Tripod.................. 601 Grinding Apparatus. . .201 to 209 Helber Counting Chamber 138 to 140, 194 Geologist’s Hammers............- 339 “with agate mortar 202 Hempel Distillation Flask........ 289 Geryk Air Pump................ 2 se Belts, Carborundum . 378 ss Distilling Tube....... 18, 237 Giles Flasks: eccics maine 6 tn eke 295 ss Machine, Rough........ 378 ee Gas Burette............ 326 Gillespie Color Comparator...... 165 ae Plates, Braun..... 203 to 205 os “Palladium Tube..... 332 Gilmer Electric Heater.......... 340 ee and Polishing Machines, “ “* Pipettes............ 834 Gilmore Needle................. 113 Metallographic. . .376 to 378 ee -Winkler Gas Burette.... 326 Glass Adapters................. 1 Wheels............ 376, 378 Henninger-LeBel Distilling Tubes. 237 ¢ AMpoulés..32 peaccecia ects 7 Guide Plate, Frost Micro...... 195 Henry Conductivity Cells........ 184 HE Boadsnaa i cots iouk cite een 335 “Breed and Brew 195, 414 Hess Viscosimeter.............. 143. Le WeDo are ces nce rete Teas 73, 74 Gummed Labels. . ...358, 359 Hevi-Duty Combustion Tube © “C@OUNUING = ska eared eae 8 194 Gutzeit Arsenic Apparatus uc ner 18 UTM A COS ie sehoee-cnin ak say ba eit os 317 9 A R cr H U R Fle T H O M A NS) Cc O M Py + 351 Hydrogen “250 Water Funnel........... _. 303 Inductorium, DuBois-Reymond... 483 Hydrogen-ion Outfit... 253 Howard Counting Chamber...... 194 Injecting & Measuring Pipette, Roth 491 Hill Filter Apparatus... . 2 Howler Seti. ices sccdeet) ha eae ad 180 Ink, Diamond...........-.--+-- 351 Hill Weighing Bottle.......... . 618 Hubbard Specific Gravity Bottle.. 545 “‘ Polygraph.........---+--. ~ 150 Hinds-Doremus Ureometer....... 145 Huber Embedding Table........ 45 Inoculating Loops........... 442, 443 H-ion Concentration Apparatus, ‘Warming Table.......... 606 . Loop Gauge......... 443 colorimetric.........144, 168 to 166 Hulett Mercury Still........ . 3866 2 Needless. wie eee 443 H-ion Concentration Apparatus, Humboldt Penetrometer....... 15 Needle Holders...... 443 electrometric.... : 243 to 262 Hummer, Microphone....... T80 -Anspissators< a2 ance ent ada ae Hirsch Funnels................. ae Hurley-Kennicott-Campbell Colori- Instrument Cases, Dissecting. . «9, B81 Histological Apparatus. . .21 to 46 MEOLET ety Seah ne ae naah 153 Sets, Dissecting leet 231 Hitchens Syringe............... 570 Hurthle-Jaquet Manometer...... 482 Interference Refractometers, Ray- Hoffman Clamps..... .132, 135 Huyghenian Oculars, Bausch & Lomb 396 TOI G acess x sired Boncomen pei AB eee 524 Decomposition of Water ae TASS ck cae oss 407 Interferometers, Rayleigh........ 524 Apparatus... 218 Hyatt-Warmouth Disintegrator... 207 Interval Timers................. Sas -Frazer Gas Collec ting Hydrant Stopeocks.......... 559, 560 Inversion Sugar Flasks... 298 Tub@s acces kt ¢ i 326 Hydraulic BUY =r ene me 509 Inverted eee Outfit. 373 Hofman Sodium Press........... 509 Hydro-Carbon Burner, Khotal. . 104 Specimen Jars. . ... 856 Water Bath..... 610 Hydrogen- Calomel Cell, Bovie.... 255 Jodine Mlasksi9 aici itn ob wins cont ee 291 Hofmeister Capsules or Schi ilchen. 112 as Electrode Vessels 248 to 251 Tron Crucibles and Covers....... 200 Hogarth Specific Gravity Bottle... 545 as End-on Vacuum Tube.. 522 © DDISHES( Joh cee hee ee ese a es 225 Hoke-Phoenix Gas Pressure Regu- Hydrogenation Apparatus... 453° | Montane: cist so05 cutoeuiee ate 438 lator & Reducing Valve .176, 328 Hydrogen-ion Concentration Ap- Ore Grinder, Braun.... .203, 204 Holders, Animal................ 11 paratus, Colorimetric 144, 163 to 166 Retorts. eg ea eae tear ave 527 i Bakelite, for Haemacyto- Hydrogen-ion Concentration Ap- Rings, Concentric.......... 529 meter Slide............ 140 paratus, Electrometric. ...243 to 262 ‘* Wire Gauze................ 619 Bitumen, Draper Model. 15 Hydrometers, various. 346 to 350 BS Burethereswts tit ware 133, 136 Ee Cylinders.......... 215 J 4 Clamp.............183, 186 te Specific Gravity 3 Crucible....... ..134, 201 A.S.T.M. and Jackson Canulae................ 485 4 Culture Dish.......211, 212 Barrett...... 17, 19, 350 ‘Specific Gravity Ap- - Dissecting Needle... . 228 Hygro-Autometer............... 350 paratus.... sty 545 ‘ Evaporating Dish d 184s “Hy Brodelle occ. ean amnn sees 351 “ Specifie Gravity Flask. 113 - Extension Clamp....... 136 Hygrometers................ 350, 351 es SUPDPOFUS 252s kes eo 479 - Gas eens chante ate aes 176, 332 Hyvac Air Pump, Cenco......... 3 3 Turbidimeter........... 603 fs Inoculating Needle . 443 JUIN VANS ve es eae Raed Gi 8 cela ee ora 357 BS TGGNS tse dia. Sten .. 3894 I Jaquet Cardiograph Attachment.. 150 7 ee ee FA ae ane oe ‘““Chronometer............. bas : ate ses 8 NES CS Pa ey eee 46 -Marey Pneumograph...... 15 Razor Blade... .. 430 Tie bes ENE bee 576‘ Portable Polygraph....... 150 : Specimen, Sauveur. 370, 371 Jer Disc Pulverizer............. 202 ‘ Sphygmograph........... 150 te LEDS omen mars: 134 Tiluminating Devices, Micro- “ Supports................ 479 Prange 26.2 se ceten tits 600 BUODE: cs esac 369 to 375 ‘© Time Marker............ 481 Watch Glass... .. 134 ‘es Systems, Metallo- Jars; VArlOUSs os.2 slink eens 352 to 358 Holdt- Gardner Surface Tension graphic. . gr ATION on.) aa, a oe eo eee 11 2 568 Jlluminator, Dark Field, B.&L... 399‘ Bacteria Grinder........... 208 Holt Milk Testing Set........... 433 «“ Spencer. 398 or SBA tLOR Vise cietc last tent See re 70 TL OWS hain he as DON eet one 430, 431 “ Tanai tee ol 403 Sto Bell Sis een sentres eae cree Oona Honing Guide, Microtome Knife.. 429 “ Verticalas 2s ane 370. 399 “ Brushes................ 86 to 88 Hooks and Chains....... 227 Trhiof Cone ou ussc. scetes bese 191 ‘ Cylindrical Museum..... 355, 356 DOU lento nek aes ea 227 fO Cup POltiercak oles 191 a Dressing. . ee ren rete Hookworm Centrifuge Outfit... 115 Immersion Oil Bottles........... 80 “ Frame Supports. eRe ae kt 353 Tubes. . 115 PEAT) RO ORCI nee 399 “ Glycerine.................. 357 pp Hopkins-Columbia Museum Jars... 354 Immunity Unit Cylinder. _... 218 “ Inverted Specimen.......... 356 Hopkins Condensers............ 177 “" Pipettes AO0 ee MU aI eh ees Ce ane 357 Picardcbaw 7 Inactivating Baths. ....... 40,43, 610 ‘ Microscope................ 73 A : odification 177 Ineinerating Dishes, Alundum.... 225 “ Museum............. 352 to 356 , Connecting Bulb....... 448 Tnclinator, Universal Carboy... 112 ‘* Naples Staining............ 556 ‘ Vaccine Tube... . 118, 127 Tyeubating Room Equipment... 32 Ointmenty ss ceicsm cbeatss 357 Horizontal Pressure Sterilizers Incubators, Bacteriological....21to 31‘: Phosphoric Anhydride... .. 176 (Autoclaves)” je te.ushoeenn cone 38 and Carrying Case,1 Frost195 “ Precipitating... 357 Horn SCOOPS ckucslcagiyeaveid: 536 “ Compartment. . 82> Preserving. 4cun nis aces 357 ae Seeger or a e Deletes oe ae 29 Rectangular Museum. . ..352, 353 ee eS ~ Bield Models... S30 4, B@Pew Camo... ci cussecn BOT Hortvet Butter Test Bottle... a 432 & Heating Plates... 27 ““ Specimen............ 352 to 356 “| Cryoscope..........209, 434 “ ase sien pia 297 «“ Staining... 556 Sugar Tube. ....... 129, 603 ‘s Low Temperature...30,31 | Stoneware................. 857 Hose Connectors................ 559 be f : ae “ gt 3 9 Micro Slide.......... 402 ORAR Ct sare nauk dt sete aironiea fe 354 Hoskins Furnaces. .....812 to 314 és “ i ¢6 Tot Plates. 343, 344 Office Shes Odean eee © 29 ¥ Supports, Specimen......... 353 Hostetter & Roberts Titrating Head 259 i Oil Heated. costae BO WAStE so cas paetaas ee ces 357 “Titration Units 259 e Thermometers....... 588 PONE Giclee heats baw een 176 “ “ «Weighing “ “ Freas.. 28 Jeffer Counting Apparatus....... 194 Burette....93, 259 Indicanometer.................. 145 Jellett Telescopic Control Tube... 506 Hot Air Sterilizers........... 34 to 36 Indicating and Detecting Instru- Jennings Connecting Bulb. 447 “Plates, Electric.........343, 344 ments, Hlectri¢s Shear Balanites 5 5400.05. seagsee 60 T Staudinger School Balance. . . 58 Beakers...........0.00005 72 Steam Sterilizers, Arnold.... . 89 ‘© ~Cane: Mills... ¢5 4.05 207 Table, Animal, Brodie. . i de Steaming Apparatus, Cement..... 114 ‘Capsules... fan ts 220 Embedding ae Mena Meade . 45 Steel Anvils............... 12 SS eM AG Steer iat sieve Su eh 297, 298 CN AS orice ea ine he atta 110 Balls: Sciacca sehen 208 A MMUNNE] So TE) Clampsen as a: . 184 Stoneware Air Pitchers........... 1 ms Spark Terminal....... 55 “ es Filling Attachment... 577 4 VATS i eRe ae OO ny Specimen, for jars..... 353 «© «Holder, Shaking... .. . aoe os Mortarse::.3 220i aveses 438 a Spectroscope.......... 546‘ “Rack, Kolmer. . “ BDamikSraion ote ot ee. eukcenn es 562 es Spectrum Tube....... 555 . : ee Sergi 40 to 3 ‘ UIP DORES Ss wee acute Stop, Funnel for Micro Bes 399 * Mableses ct keracsek iis 566 Postene Baucoee WEE «ac. 431, 432 Stopclock. . lace Keates "OOL Telescope............. 578 “ Hardress 339 Stopcocks, 7 various........ 558 to 561 « Test: Tubes... ccacnkacs 578 “ Mille Sediment... 434 A Burette.............. 98 5 i “ Serological 40 to 43 Theleo Electric Oven............ 467 a Syringe Needle Sera ee 572 ae Titration. 22sec ccs es 96 Thermo-Couples, Pyrometer ..514, 515 Stoppers, Rubber............ 532, 533 ai Vacuum Flask........ 287 a -Electric Pyrometers...... 514 Stopwatches... 422.40. 455506 cake 562 es Water Bath.. ... 602 as -Regulators. . .594 to 597 Storage Battery: isaac fee 69 - and Water Baths, ‘Ex- i A.&S...... tee “Hydrometer 349 traction.............. 268 Thermo-Regulator, Electric... ... - DATS raat cin nee aes 354 o Weighing Bottle....... 618 Thermometers, various . .581 to =o ee RANKS ccveee eesti we es ae 562 2 Wooden,......... 305, 306 - Air, Melting Point a Stormer Viscosimeter............ 455 Swan Blood Lancet.............. 151 “ Acie Bate one 585 Stove, Actuating................ 32 Swimming Cups................ 568 “ ATSchigte, Mise oe 585 Straub-Jaquet Manometer........ 483 Switchboard, Electrolytic.....241, 242 ‘ Armored......... 585 «© -Marey-Jaquet Recording Switches, Knife................. 568 “ Asphalt.......... 585 TPambourasiasscieeass. yes 481 Sy Digestion Apparatus.......... 447 eo Baier............ 520 Strauss Funnel................-- 304 ‘ Extraction Flasks......... 263, 290 as Beckmann........ 586 Streak Plates. . .496, 562 Syphons, Glass................. 568 ee Benzol and Toluol 18 Stretcher, Rubber Tubing. . eee ens 535 Syphon Tubes, Extraction....... 266 & Calorimeter Strop, Dressing.............-..- 431 Syracuse Watch Glasses......... 608 106, 107,109 to 111, 587 6 VRAZORG Check natin eae 430, 431 Syringes, various.......... 569 to 573 fe Conductivity Cell Student’s Compartment Incuba- . Needle, Blood Letting... 572 185, 587 tors. a een ee . i GU CR a sesso eetcatsoe 570 ss Cryoscope 209, 434, 587 Suberite ‘Rings Rieter nye age 529 ie Record . 570 is Distillation.....18, 588 Substage Condensers............. 397 “Rack... 0... 570 s Ebulliometer. .240, 588 ae Micro Lamp........... 410 be and Sugar Hydrometer.. 349 Embedding Table.. 45 Sucrose Pipettes. . ....... 493 System, Moving, d’Arsonval Gal- fe Floating.......... 588 Sugar Analysis Dish, ‘Silica ora 224 vanometer................... 262 ne Flash Point Tester. 588 A R T H U R Fl T H Oo M A 8 Cc O M P A N x Page Page Page Thermometers, Freas Oven....... 469 Torsion Balances............... 62 Tubes, Funnel.................- 305 Gas Meter........ 333 ef Cream Balance.......... 434 ie Furnace, Carius.......... 311 Gasoline... . .. 455 5 Moisture Balance........ 63 iS SE Wea yes ek ee Ok Heidenhain....... 486 Toxin Filter Apparatus...... 273 ie as Hoskins ‘Combus- Incubator........ 588 Tralle & Proof Scale Hydrometers. 349 TION: Sciacca nd BLS e Freas... 28 Transfer Pipettes. . : 487 “Gas Absorption, Blount... 326 Limpid Point..... 19 Transference Apparatus, Findlay.. 598 e “ Collecting. . 11... 826 Low Temperature. 589 Washburn 599 re “ Interference ‘Refracto- Maximum and Transformers............375, 528, 529 MetOR<. Aevt te sentsis Minimum... 589 Transport Apparatus. . rote 598, 599 es ““ Measuring........... 332 Melting and Boiling Trap, Ammonia................. 146 os “ Palladium, Hempel... 332 Point. 589 Traube Stalagmometer........... 143 = Glass, Furnace........311, 335 Mojonnier. Vacuum Trays, Dissecting............... 599 ue Goetz Phosphorus........ 128 Oven..... sp Als ‘“ Enamelware.............. 599 ‘““ Haematokrit Blood....... 118 Molecular . Glass. . Vasahs yon ee oo a Hart Casein.............. 128 Weight....... 435, 589 Sy Micro Slide. Rte ep eA 415 i Hempel Distilling........ 18 ; Oil Tester... .. 451, 452 re Paraffine Conbamen . 43 % Holder, Myer’s Centrifuge 117 i Oven... ...... 590 Triangles .... Whieanieg ress O99. 600 “ Hookworm Centrifuge..... 115 : Paper Seale... . 582 Triangle Wigan ee se 600 “Hopkins Vaccine..... .118, 127 : Pocket........... 590 Trip Balances.. : ......60, 61 oe Hydrogen End-on Vacuum 522 ss Readers....... 106, 593 Triple Beam Balance... ede kOe Pm Deni tion eco: 6 see hae aks 576 : Recording........ 591 “Wall Sterilizers........... 35 os Melting Point............ 366 : Refractometer..... 591 Tripods .................. 600 to 602 ee Myer’s Centrifuge........ 117 e “Abbe 519, 520 Tripod Magnifier................ 362 . Nephelometer, B.& L.. 156 ss “ Butter... 520 Troilius Nitrogen Bulb........... 448 o Kober..... 158 - ‘ Dipping.. 521 Trough, Colorimeter. . 159 a Oil Centrifuge............ 128 5 “ Pulfrich.. 522 ae Condenser, A. S.T. M. and oi Photometer, Nutting. Hak Dol tS ‘“ Sugar.... 520 Barretts caw sateen 17 ““ Polariscope............-. 505 ss Sand Testing..... 585 a Pneumatic.............. 602 es Pyrometer, Porcelain...... 515 : Slide Incubator.... 402 Troy Prescription Weights....... 68 : Receiver, Distilling ...... 238 a Sterilizer......... Doe PET OSe. yen cesius wud iecuetscn ee ern hate 602 ne n * Tube.. 453 st Tar & Pitch Testing oo Tubes, Absorption............... 554 - Receiving, Folin...... 147, 577 a Titer Test........ Aeration, Urea Apparatus 148 ee Reduction cote. ec oats 517 ; Urinometer....... ae - Agglutination............ 128 or Salt; Bridge. a acdvcusns onan 251 - Veterinary........ 592 ‘* Ammonia Absorption, Folin 146 et Silica Connecting......... 237 4 Viscosimeter i SATSONI Gregan Genet cms Cees 13 ef Spectrum................ 554 455 to 459, 593 : Babcock Centrifuge....... 127 $8 UBAT ort tate het tae aie 603 Warm Stage. . 593 “ Balance, Centrifuge....... 129 os PS EVOLEVICG sete z!t. caeneunne 129 Water Melting oy Barometer............... 69 ee “Vivien. Bs . 129 Ponte ro ce 2a 2 18 “Blood Culture, Keidel _ Sulphurie Acid Drying, Van- “ Wrollltty. 25 2) accs cso 520 Vacuum.......... 151 ier. .176, 239 Thiele-Dennis Melting Point Tubes 366 = SS Sugar. . ee eh 577 i Supports, Golotecccn ee 152 Thimbles, Extraction............ 264 2 Board of Health. . atm 128. “ “ Fermentation...... 270 Thistle Tubes....... .... B05 * Calcium Chloride. . .. 105 i Syphon, Extraction....... 266 Thoma Blood Diluting Pipettes, .. 141 2 Carrier, Absorption. . Riya Venia 550 oe Test ...... .574 to 577 Thorn Extraction Spparens:- . 266 Sy Centrifuge..... 118, 127 to 129 us ce Barrett «+0 4 shen ee 19 Thread Counter....... .... 868 a Blood...... 118 a TIstleicn ie Pe eeiiee oh ns 305 Throttle Control Valve. . SUeto28 “Color Comparison... ..... 152 pan) ARE Shialpeieten ui ateateratin 2c, 6 602 Tiles, Pill. . tk fae LOO oe Colorimeter, Bausch & ss ees epee teatae tMem ed aan 603 Time Markers, ‘Electric. sone 2Od Lomb....155, 156 Be NAS COSIDYsitk tah soe aes 606 me TOVCr aetlareeciee Ga. 150 ne rs Duboseq.... 157 es Wassermann Centrifuge... 127 “Marking Clock, Brodie..... 480 a es Kennicott- ys “VSM A Gls hints Asean ot es 602 Timers, Interval................. 151 ee ee Campbell- es Zine Drying, Vanier. . .176, a3 Win s BOXCSt, 4 = eh ed eee 86 Hurley...... 153 Tubing, Alundum............... “Foil Bottle rape Dishes)... 226 ae a Kober....... 158 es Band. Se ea tee Ee soe = SPI Ores.qhiois veer olka oA . 485 i ie Myers....... 160 “ Clamp 2 ey Tincture Press................-. 509 ~ Schreiner.... 153 ee Corrugated Flexible... 367 Tinners Shears. . RAPURG AR este OOD ty Combustion.......... 175, 176 e Cutters, Glass....... 335, 336 Tintometer, Lovibond........... 162 a Condenser ...........146, 177 ee Blexiblecn sice fess 104 WeSSON... «2h ee kaa 162 < me A.8. T. M. and “— Metallic........ 603 Tips, Blowpipe......... yimechas VLD zs Barrett ..17, 18, 19 ss Gauge, Glass............ 336 irri Burners... ceaw a ewes 98 ee 3 Brown-Duvel. . 178 tf GlaS8 oo oe eee 336, 337 Titer Test Thermometers......... 592 a Connecting, A.S. T. M. and eS Haemacytometer........ 535 Titrating Head, ee Roberts fea Ferret biveas dl “ Nitrometer. . Cee tae Titration Outfits, Electrometric. . . re ume........ 146 “Par Pesta des * “Oeutowdelst Bue eee Dialyzer.. ae ‘ “ _ Electrometric “ @ulbure si... 2.218; 214, 575 ““ Rubber.......... 534 535 Kelley... .260 to 262 ‘Digestion, Folin....... 147, 577 “Silica. . Men recA “ Electrometric “Discs, Extraction......... 265 “Stretcher, Rubber........ 535 Roberts........ 259 ‘ Distilling ee .237, 238 Tubulation Clamp.............. 597 “Volumetric... 96 Watson and White 147 Tumblers, Glass 72, 603 6 “Support. nc. esses 96 ‘Drying and Potash Bulb, Tungar Rechheee oe 517 re Unit, Roberts Electro- Vanier Combined.... . 172, 239 Poni Teen ee ee mee 482 metric. 259 ‘“ Electrometer, Paei anys 246 mee SSE es Dea me rai Toluol and Benzol Thermometers 18 ' (Extractionees Gerd vce ne 264 urbidimeter Jackson........... 603 “ Thermo- Hegulevors re etter 595 “Fat Extraction... . 434 U. S. Geol. Survey Ton Weight, Assay. . sidan Od ‘“ Fermentation............ 270 ae TY DG jin cen sat eee O04 Tongs, Crucible. . ie were _ 597 “Filling Attachment....... 577 Turbidity Seale................. 604 Gipele ee re: 597 pa. AB Conen he cha ease eae ed 282 Turbine Stirrer, High Speed. ..... 558 o Gas: PIPGs 6 ccna acke pence 498 “Fume Absorption......... 146 Tiirk Counting Chamber . . .138 to 140 18 A R T H U R EE. T 4H Oo mM A 8S Cc oO M P A N Y Page Page Page Tutwiler Gas Burette for H,S..... 325 Van Slyke Amino Acid Nitrogen Washing Bottles................ 607 Twaddle Hydrometers........... 347 APPAaratusy < ceoiccd-o es 450 Wassermann Baths weaves 40 to 43 Two-Stage Auxiliary Air Pump, Blood gas Apparatus.. 149 Centrifuge Tubes... 127 Were cha a Sider ens ah Sate te 2 -Cullen Urea Apparatus 148 ce Mailing Case. . 363 Ty: phoid Mailing Case........... 363 Vanier Genoa Potash Bulb and 4 Needle............ 151 Drying Tube......... 172, 239 a ey Brohit aun ariae 489 U “Combustion Train.....167, 168 a Racks. . io: Drying Tube, Sulphuric Waste Jars.. B57 THA estan sands nd ROR Ae 603 Acid... .176, 239 “~~ Pail, Enamelware. . 607 U-type Conductivity Cell........ 185 o i “ Zine....176, 239 Watch Glasses ...... 607, 608 U, G. I. Gas Burette............ 326 “Potash Bulb and Drying “Glass Clamps, or Holders... 134 ee “Pipette. 334 Pub ery vedere meas Sete 508 Watchmakers’ Ra erent 362 Uhlig-Elliott Ge Analysis ‘Appara- Vapor Air Pump, Mercury..... . 1 Water Analysis Flask... 289 Se Lee, toe Opa care 32] Density Apparatus........ 604 ee Baths: os 6.5 "609 to 616 Ultra-microscope Condenser, Sied- Variable Air Condenser.......... 182 - “(Dyes 239 entopf. . _.. 39g Vaughn Animal Cage.......... 10 P “and Extraction Sup- ‘ Outfit, Zeiss.... 408 Veeder Hand Counter (Tally ports. . gins ana LOS Ulira- violet Quartz Spectrograph 552 RESIS HET) a Sedencnan tem ee & upske no Ne 193 e “ Rack.. wees Ob] Ultzmann Polariscope. . 507. Vernier Srarins Unis etre etait ae i “Serological... .40 to 42 Units, Heating, C.8.&E. El 5 ONGENSER. fie 5.4 oe Mae 82 . SUP POLGR dau van ees: 602 Unit Type Dial W Theatstone ae a Vertical Illuminators......... 370, 399 “Decomposition Apparatus 218 Universal Burner............. 9s Vessels, Calomel Electrode....... 249 “Distilling Apparatus 232 to 238 Clamps........... 132, 133 : Connecting.............. 250 “Examination ne: Gano vie OLE Colorimeter, Autenrieth- HMlectrodes x accsncce = 249 to 251 “Heater, Fletcher. . sens OL Koenigsberger......... 159 “Hydrogen Electrode . 250 = Jet Bilter Pump, ++ sia v:a5. 282 Ure Eudiometers................ 263 Liquid Junction......... 250 “Level Regulator.......... 610 Urea Apparatus, Folin...... 146 Standard Cell........... 247 “Mailing Case. 363 és ce Marshall. - 14g Veterinary Thermometers........ 592 ‘“ MeltingPointThermometer 18 Van Slyke ‘and Vials Shells 68 ante, peat ilvaite 605 ue VID LOTettey sere ie arora tet 439 Cullen... --- 2: 148 Specimen cose deca se) 605 _ “Centrifuges... .115, 116 i Bulbs Rolits: soe se _ 146 Vicat Needle Tester.............. 113 “Pressure Tanks, Refracto- Urease, Dunning................ 148 Victor Interval Timers. . tec LO IMELCMeliry tania t win Sse c 523 ‘“ Squibbsste aac 148 Victor-Meyer Funnel............ 301 ‘Sample Bottle............ 85 Ureometer, Doremus-Hinds...... 145 Vanae Deity A a Aik : a a Apparatus, Es- i Tri 7 a Seto h- Edintan ib sascha teh beiaen Tae ( Tne ani Blood ey fe y49 Virchow Knife.............. 227 o Spray Type Air eoeeine “ “ “ Pipettes........ 491 Viscosimeters, various..... 455 to 459 Apparatus, Palmer. . ee 6 Urinometer, Squibb............. 146 Asphalt occa sis cies 15 Watson and White Distilling Thermometers....... 592 ne Flasks... .....298, 459 HEU Cie aire Wires Manat ee aa 47, 448 « Vogel... on SHAG is ““Saybolt.... 456 Wavelength Spectrometer, Hilger 549 U, S. Army Incubator. . ‘ 30 : HOSS Re ae dens seca 143 a Spectroscope, Gaertner 548 “ Daraffine ‘Compart- cs Pipette, Saybolt... 456 ot Schmidt ment Tray 43 Thermometers ; &Haensch 547 ee ce Embedding : : 455 to 459, 593 Wax Pencils EVA AGRA ny roe eee e tam: 475 Bath........ 42. Viscosity Apparatus, Blood....... 143 Wax, Sealing................... 618 «“ Serological Baths... 42 se Pipette, Dudley........ 455 Wayte Centrifugal............... 130 ete