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IMaps, plates, charts, etc., may be filmed at different reduction retios. Those too large to be entirely included in one exposure are filmed beginning in the upper left hand corner, left to right and top to bottom, as many frames es required. The following diagrams illustrate the method: Les certes, planches, tableeux, etc., peuvent Atre filmto k des taux da rMuction diffArents. Lorsque Ie document est trop grsnd pour *tre reproduit en un seul clich4, il est film* A partir da I'angle supArieur gauche, de gauche i droite. et de haut an bas, an prenant la nombre d'imagas nteessaira. Les diagrammes suivents illustrent Ie mAthode. ita lure. ] 1 2 3 1 2 3 4 5 6 .•^-mti. •J < G 1 ALBUM OF DESIGNS OK TIIK PHCENIXVILLE BRIDGE-WORKS. CLARKE, REEVES & CO., OFFICE No. 410 WALNUT STREET, -«^ PHILADELPHIA. J. B. LIPPINCOTT & CO. PHILADELPHIA. 1873. H- TiK Aui {1)11 E] tc tl I o tl V 1 f e J Thomas C. Clakkk, AllULfHUS DllNZANO, {CHIN Gmi'mN, )AVI11 KliUVUS. PIKUNIXVILLR HRIPGR-WORKS. Offich of CLARKE, REEVES & CO., ENuINEERS, CONTRACTORS, AND BUILDERS OF IRON BRIDGES, VIADUCTS, ROOFS, ETC. NO. 410 WALNUT STREET, ROOM 2. P. O. Lock Box No. a. p JJ J I ^ D \l L P H J A. In presenting our second circular, we take occasion to call the attention of our friends and customers to the following points: We have entered into contract with the Phoenix Iron Company, Phoenixville, Pa., for a long term of years, by which that Company transfers to us all their iron bridge-building, and orders for bridges and viaducts are handed to us for execution. By this arrangement the whole resources of the Phoenix Iron Company can be concentrated upon tiie fulfdlment of our orders. Their present facilities are equal to turning out o/zc hundred feet of finished bridge for eaeh ivorkiitg day in the year, and can be increased, in case of necessity. Everything is done upon the premises; beginning with the manufacture of the iron from tlie ore, next rolling it into the sliapes required, and finally apply- ing the machine-labor that completes the structure ready for erection.* It is believed that all this is done by no other single company in this country. It results in a uniform excellence of quality of iron and workmanship, which cannot be got from bridge- builders who procure their iron from different makers, and generally at the cheapest rates. We are prepared to construct any style of wrought- iron bridge, and according to any specified dimensions and wciglits ; at the same time, we would call the at- tention of engineers and railway-men to that style of bridge which we have been building during the last five years, which has stood the test of use, with the marked approbation of those best able to judge. ''' See description of Pliojnix Works, illustrrtleil by woodcuts. Ex- Iriictecl, by permission, from Lippiiuotl's Mai;aziiie. Appendix No. i. What we claim as the peculiar advantages of our bridges are as follows : We use that style of truss (originally developed in wood by Pratt and in iron by Whipple) which expe- rience has shown to be the best adapted for railway purposes, as there are more of them in use in this country than of any other kind. So far as we have modified the connections and other details of construction, we have endeavored to be guided by the following principles : Simplicity and uniformity of construction ; least pos- sible exposure of surliice to corrosion ; uniformity of strain on all parts alike ; concentration of material along the lines of strain ; and the use of the most suit- able kind of material for tlie purposes required. At the request of many railway-men, we have pre- pared a set of der>igns, accompanied by detailed speci- fications, covering the proportions and quality of material and workmanship under which they will be constructed. They have nearly all been actually built by us, and have borne the test of use. Persons requiring bridges will find among these everything they want, unless for special ca.ses, for which we will prepare special plans and estimates, free of charge, when requested. We build our short spans stronger than has been heretofore customary, providing for a variable load of two tons per foot. We do this, because there is gen- erally no slackening of speed in crossing a short span, and the live load of the locomotive bears a much greater proportion to the lead-weighl of the structure in short than in long spans. At 250 feet span the live and dead loads are nearly equal, while on a 30-feet span the live load is more than four times the dead load. PIUENIXVILLE BRIDGE -WORKS. As the live load is accompanied with imi)act and vibra- tion, and foiir-fiftlis of the strain comes from it, it is but prudent to taice this into account.* In i)roportioning the different parts of our bridges, the strain i)er square inch is diminished ; or in otlier words, tiie strength of each part is increased in pro- portion to its nearness to its work. As the panel system is fully strained by the passage of each locomo- tive, it should have greater strength than the chord system, which can only get its maximum strain when the whole length of the bridge is covered with loco- motives, which in practice seldom occurs on spans longer than loo feet. The bolts which support the floor system, being subject to accidental shocks, have the greatest strength of all. This is merely follow- ing out in p.actice the principle of "uniformity of strains." Inasmuch as the strength of an iron bridge (like that of an iron chain) is measured by the strength of its weakest part, it follows that the structure in which tiiis principle is most accurately carried out will be the strongest, while the purchasers of the bridge will not be compelled to pay for useless iron, which diminishes instead of adding to its strength. On the other hand, if bridges are too light, they will show this defect by excessive vibration under a passing train. This fault, we believe, our bridges cannot be charge.W ■- 54 I. I— 841 4 — I >;) I 4—120 )' 2— 13, I 2— iSfi.f)/ WillUli! laiLT. Ches. ft Ohio R. R Rivanna Creek S. Schotield .M.inayunk, Highway. Ohio ft .Miss. R, R (.lochran No, u " " Medora " " Scoltvillc WestKork " " "Ik SuKar " " Little Siiijar Little Wabash,, Grand Trunk R'wayofCau, St. Hyacinthe.. " " .. I'.lack River .. White River... 3756 ;l 3480 .85 340 248 660 •116 226 231. . ,St. Francis M:.>;oK , Massawippi.... . Ctiaticoku Island I'oiui.... jN. Stratford... . Ammonousuc. , (it^rhain , \V. Paris , S. Paris Mcchan's Fall* . N. Vaniumth. Philad., Wil.Ct Halt. K. R. Ridley Park. Rock Isl.iiui Ar>cnal Central R. R. of N.J Nurlh Pennsylvania k. R (.lenevait Ithaca R. R.... 5" 80 129 M9 ij8 Molinc. III.. Panirapo. Sellersvillc . 'ranylianock... . SheUlr.ikc t'err ■ , 'IVninan^liuri' , Senega Car il ? tracks Costa Uica Railway Costa Rica, City of Pliiladclphia NO. LCNGTIt. ( Cirard Av., I'xi feet wide."! Seven trusses. I''tiiial to ^ ( six railroad tracks \ {:= (.-: 97 93 M5 ■47 "47 I 163 J '77 307 >"3 33 93 27) ( I- 1 1- ( I- ■(■- ■154 1 ■73f ■IS.) •M"i 118 "7 ■■7 107 i"7 124 ■47 ■ 38 -63I 96-3 102 104 QOO 88 -.V3l - 68 I - 74 I - 16 I ■97 I ■37) 97 93 •45 •47 310 53' 4^4 I>3 3-' y2 37' ■55 232 297 ■'■7 "7 107 ■■7 '-■4 '47 ■ 38 121 94 289 lo» QOO 88 w GENERAL SPECIFICATIONS, ACCOHDINO TO WHICH THK DESIGNS OF CLARKE, REEVES & CO.'S BRIDGES, GIVEN IN THIS CIRCULAR, m re ARE PROPOSED TO BE CONSTRUCTED. 1. These structures are proportioned to sustain the passage of the heaviest cars and engines in use, for coal, freight, or passenger traffic, at a speed of not less than thirty miles per hour, viz. : two locomotives coupled, weighing thirty tons on drivers, in space of twelve feet; total weight of engine and tender, loaded, sixty-five tons each, and followed by the heaviest cars in use, viz. ; loaded coal cars, weighing twenty tons each, in twenty two feet. The iron-work will be so proportioned tiiat the above loads, in addition to the weights of the slruo tures themselves, shall not strain the iron over 10,000 pounds per square inch tensile, or 7500 pounils per inch shearing strain, and reducing the strain in com- pression, in proportion to the ratio of length to diam- eter, by Gordon's formula. 2. The iron used under tensile strains shall be of tough and ductile quality, and be capable of sustaining the following tests : THCENIX DOUlil.E RICFINED OR "BEST BE.SI" IRON. ROUND llAK.— li INCHES I,.amktKR IIV 12 INCIIKS I.ONC. Ultimalc sircnglli, 5?,ooo to 60,000 ll)s. [jcr s(|ii,uc inch. No perm.-ment set \indcr 25,000 to 30,000 " " Reductimi of area at breaking point, average 25 per cent. Elongation " " " " i.5 Cold bend witliont signs of fractnre, from 90 to 180 degrees. 3. All workmanship shall be first-class. In work having pin connections, all abutting joints shall be planed or turned, and no bars of wroiight-iron having nn error of over i-64th of an inch in length between pin-holes, or over i-iooth of diameter of pin or hole, shall be allowed. In riveted work, all plates and joint plates shall be square and truly dressed, so as to form close joints. Rivet holes shall be spaced accurately and truly opposite. Rivets shall be of the best quality of rivet iron, shall completely fill the holes, and shall have full heads. Chord-links, main ties, and suspension bolts, shall be die-forged without welds. Screw-bars shall have threads enlarged beyond diameter of bar, and shall be fitted with radial nuts anil washers. All liars subject to tensile strains may be tested to 20,000 pounds per square inch, and struck a smart blow witli a hammer while under tension ; and if any show signs of imperfection they shall be rejected. All the iron -work shall be painted, before leaving the Works, with one coat of metallic paint and oil. All machine-cut work shall be covered with white lead and tallow before leaving the Works. 4. These bridges shall not deflect, under the passage of a train of locomotives moving at thirty miles per hour, over i-i 200th of their length, and shall return to their original camber after the passage of the train. (4) DKSCRIPTION OF PLATBS. I PLATE Wo. 1. Desic.n a — Figs. I, 2, 3, show i\ simple form of girder bridge intended for spans of 25 feet and under. It consists of two pair of rolled Phcenix beams, of 13 or 15 inches deep, according to span, braced to- gether and resting on (ast-iron i)lates. Where the headway is extremely limited the arrange- ment sliown in cross-section, Fig. 4, may be iised, which requires a depth below bottom of rail of but 11 inches. PLATE No. 2. DKSKiN H is a trussed girder with two panels, in- tended for spans of 25 to 30 feet, where there is suffi- cient depth below the rail to truss the beams in the manner shown. PLATE No. 3. Desr;n C show's a trussed girder with more than two panels, suited for si)ans of 30 to 75 feet. PLATE No. /». Ukskin D. — For longer spans than 75 feet we use our regular pattern of deck bridge, with top choi Is and posts made of Piuenix columns, and having side cross floor-l)eams. The track stringers can be either of wood, as shown in the plate, or of iron, if specially ordered. Where jireferred, the tojjs of masonry piers need not be carried above the bottom chords of the iron truss, and the level of bridge seat at abutments will be the same. In this case the ends of the iron trusses will be supported on vertical Phcjenix columns. PLATE No. 5. This plate shows the details of construction of the deik bridge illustrated in Design 1), J'late No. 4. PLATE No. 6. Design E. — This plan of what is sometimes called a " pony" truss bridge is used for through bridges, where the 'depth below rail is somewhat limited, in spans of from 30 to 60 feet, and may be carried up to 80 feet at points where it is desirable to give the engineer an un- obstructed view over the tops of the trusses. We pre- fer, however, at 60 feet span to carry up the trusses and brace them overhead. PLATE No. 7. Design F. — 'L'iiis is our regular pattern of through bridge. 18 feet and upwards in clear height, and 14 feet in clear width for single track. For doui)le track we recommend two trusses, with a clear width of 26 feet. PLATE No. 8. This shows the details of construction of the through bridges shown .n designs E, F, and the highway bridge design G, Plate No. 11. PLATE No. 9. Desion H This is our regular pattern of through pivot- bridges, with our patent turn-table, of a simple and effective construction. Where a pivot-pier has to be specially construe ted, considerable economy will be obtained by carrying uj) a circular wall of masonry, and reducing the dei)th of iron ring, as shown in Fig. 35. Our [livot-bridges have always given satisfaction ; and we refer particularly to that over the Hudson River at Albany, belonging to the New York Central and Hudson, and the Boston and .Albany Railroads, as a model of a quick-working and substantial pivot- bridge. PLATE No. 10. This plate shows the details of our patent locking and self-centring arrangement for pivot-bridges, the operation of which will be best understood by the description of the patent itself, dated June i8, 1872. IMPROVEMENTS IN PIVOT-BRIDGES. Our invention relates to certain improvements in pivot- bridges, too fully explained hereafter to need preliminary description ; the said improvements having jr their object, first, the ready withdrawal of the corner-sui)ports of the bridge, when the latter has to be turned on its pivot, and the ready restoration of these supports when the positior of the bridge demands them ; and second, the self-centiing of the bridge, so that the nice and tedious manipulative ad- justment demanded, in order that the rails of the bridge may coincide with those of the permaneni track, is rendered unnecessary. In the accottipanying drawing, Fig. 37 is a view of a portion of the end of a pivot-tiridgc ; Fig. 36, a side view of a portion of one end of the bridge ; Fig. 38, a plan view of Fig. I ; and Fig. 39, a perspective view illustrating a part of our invention. A and A' are two transverse beams at one end of the bridge ; these, together with other transverse beams of like character, supporting the longitudinal beams B, across which extend the ties D for receiving the rails tt a. The transverse beams A p.re secured to the lower chord-beams by suspension-bolts i\ this lower chord forming part of a truss-frame of which the pivot-bridge is composed, and of which F represents a portion of one of the diagonal end posts. To the transverse beam A are hung, by means of a pin /, a series of links /' /' / /, and to the latter are hung, by means of a pin J, a series of similar links w, and to a pin passing through the lower ends of the latter series of links are hung two rollers, //, which are guided vertically by brackets ^ y, secured to the under side of the beams A. The two sets of links, as will be seen hereafter, form a knee- joint to the central piny, of which two rods, GG, are jointed, the opposite ends of these rods being connected to the lower ends of arms H, which are hung to the transverse beams A A, and these arms are connected, by a rod, I, to lugs on a nut J, which is adapted to vertical guides arranged be- tween the two beams A A, the said nut being also connected by similar appliances to knee-joint links arranged at the opposite corner of the bridge, which is not shown in the drawing. The nut J is controlled by a vertical screw, so (S) DESCRIPTION OF PLATES. confined to suitable bearings //, ser- ed to the beams A A, that while it can be turned easily it is incapable of vertical movement. This screw may be operated by any suitable mechanism, but we picfer to operate it from a central point on the pivot-bridfje, and to connect the ojierating mechan- ism by means of a horizontal shaft extending along the bridge beneath the ties, one end of the shaft being geared by bevel-wheels to the screw K at one end of the bridge, and the opposite end to a similar screw at the opposite end of the bridge, so that the knee-joint links, at r.li four corners of the bridge, may be operaii;d simultaneously from one point. The outer ends of the rails a ii, at each end of the bridge, admit of being raised and lowered by the same mechanism which operates the knee-joints. Thus the rails rt a, in Fig. i, are connected by rods jj to the rods I l.and these rails are adapted to chairs (i d, which are secured to the permanent roadway or permanent part of a bridge, and which receive the ends of the permanent rails b b of the track, the chair thus insuring the coincidence of the rails of the pivot-bridge with those of the permanent track. As seen in the drawing, the bridge is supposed to be closed, and free for the passage of trains, the rollers / at the lower end of the knee-jointed links at each corner of the bridge bearing in a cavity in the top of a plate /, secured to the foundation or pier ; and, the pins of the knee- joint links being in the same vertical line, the links afford a steady support for the bridge at each of its four corners. When it is necessary to swing the bridg? round, the screw K, at each end of the bridge, is turned so as to elevate the nuts J. This consequently draws the rods G and 1 in the direction of the arrows, and therefore so acts on the knee- joint links as to elevate the rollers// in their guides ; and tl'.is is continued until the bridge is in the tirst instance lowered and supported on its centre jjivot only, and after- ward until the rollers are clear of their bearings. Simul- taneously with this movement of the knee-joint links, the outer ends of the rails, owing to iheir connections with the rods 1 I, were elevated clear of the chairs d d, as seen in Fig. 4, and conseciucntly the bridge is free to be turned on its pivot. In restoring the bridge to its original position, it is turned round until the rollers //of the knee-joint links are above tl^c cavity of the foundation-plate /. It is very rarely, however, that tiie bridge can be arrested in its movement at a point where the said rollers are directly above the centre of the said cavity ; but as soon as tlie screws K are operated to straighten the knee-joint links, and the rollers q begin to bear upon the plrtes /, the weight on r.ie rolleis will induce them to descend into the cavities of the plates, and hence, as the straightening of the knee- joints is continued, the bridge will be slightly turned, until* the rollers have r.rrived at the most depressed portion of the cavities ir, tlie plates, and there remain while the st.;i'.ghtcning of the knee-jointed links is continued until their pin^ are in the same vertical line, as shown in Fig. i. .\ftcr the bridge had adjusted itself in the manner described duiing the picliminary straightening of the links, and this straightening was continued, the rails a a on the bridge descended until they rested in and were contined laterally by the shoes d d of the pen lanent track. It will be seen, therefore, that by connecting these rails ati to the mechan- ism which operates the knee-joints, the said rails are ele- vated out of the chair simultaneously with the releasing ot the bridge from its corner-bearings, and when the knee- joints become the corner-bearings the rails are lowered into the ' hairs, and their coincidence with the rails of the permanent track is thereby insured. The accidents which have frei[uently occurred through the non-coinciding of the rails of a pivot-bridge with those of the ijerm.incnt trajk are thus prevented. The knee-joint bearings at the corner of the bridge pos- sess this important advantage, that they can be operated with com|)aratively little exertion, either through the me- dium of the mechanism described or any equivalent oper- ating devices. Although wo have shown and described a pivot-bridge constructed in a manner which we deem most appropriate, it should be understood that our improvements arc appli- cable to any pivot-bridge. A change in the operating mechanism may be demanded in a l)ridge constructed in a manner ditTering from that described, but the principal features may remain ; these features l)eing the knee-joint links, forming corner-supports which can be easily with- drawn, and ;'ie plates /, 'vhich lender the bridge self- centring. We claim as our invention — 1. The combination, with a pivot-bridge substantially as described, of knee-joini supports and the mechanism de- scribed, or any equivalent to the same, for operating the said joints. 2. In combination with a pivot-bridge having movable links as supports, we claim plates /, constructed, substan- tially as described, so as to render tiie bridge self-centring. PLATE No. 11. De.sign G. — This is our usual jjattern of highway bridge, with floor l)cams of iron, which may or may not be trussed, according to the available depth below roadway. It is constructed exactly like a railway bridge, except in the floor system, and is calculated to su.itain a load of from 1500 to 2500 pounds jjer lineal foot, witli a f''''tion of safety of 5. Teams may cross these bridges at full speed without doing any mischief. PLATE No. 12. Design I is an iron highway bridge-, 'a> be used for roads crossing over railways. Fig. 45 is intended for points where abutments are already built, or where, from the railway being on a curve, it is not desirai)ie to obstruct the view. On the right side of Fig. 45 a more econo'viicai construction than the ordinary stone abutment is suggested. PLATE No. 13. Design K shows our method of constructing wrought- iron piers for bridges, viaducts, etc. Tiiey are made of four Phoenix columns, braced together as shown, and secured at the joints by our i)atent system of connec- tions. As tlie lengths and weights of spans increase, we in- crease the dimensions of the columns and braces, but t!ie same ^;eneral form of construction is followed for all lengths of spans. PLATE N(j. 14. De,sI(;n I, shows a bridge on iron [liers, intended for I'.ie crossing of a smail stream or road, where good stone foi masonry cannot easily be got. The jjiers can be biiiit of s])lit bouldeis, or of concrete, if stone cannot be had; and, as they are biirieil in the embank- ments, concrete will answer as well as stone, 'i'hese piers can be coped with stone or iron. Design M shows a wrought-iron viaduct resting on cast-iron screw piies, and suitable for crossing the wide river bottoms of the western and southern States, where stone is scarce, anil where a wide water-way oust be permanently maintained. APPENDIX No. 1. PH(ENIXVILLE BRIDGE -WORKS. REPRINTED FROM LirPLXCOTTS MAGAZINE FOR JANUARY, 1873. *'assi:miu.iN( iin.i; i:ni)I;k siii:i». In a grave). ml in Watcrtown, a village near Boston, M.iss.iihusetts, there is a tombstone ( immemorating the claims of the departed worthy who lies below to the eternal gratitude of posterity. The inscription is dated in the early part of this century (about iSio), but the name of him who was thus immortalized has f.ided like the date of his deatli from my memory, while tlie deed for which he was distinguislied, and which was re( orded upon his tombstone, remains clear. " He built the fimious bridge over the Charles River in this town," says the record. Tiie diaries Ri\er is here a small stream, about twenty to thirt\- feet wide, and the bridge was a simple wooden structure. Doubtless in its day this structure was considered an engineering feat woi thy of such ])osthumous immortality as is gained by an epitaph, anel afforded such conveni- ence for transportation as was neetletl by the commer- cial activity' of that era. From that time, however, to this, the ( hangcs which have occurred in our commer- cial and industrial metliods are so fully indicated by I the changes of our manner and method of bridge-build- ing that it .vill not be a loss of time to investigate the \ present condition of our abilities in this most useful I branch of engineering skill. In the usual archiTiological classification of eras the Stone Age precedes that of Iron, and in the history of bridge-building the same secjuence has been preserveil. Though the knowledge of working iron was acquired by many nations at a ]ire-historic period, yet in quite modern times — witiiin tliis century, even — the inven- ion of new processes and the experience gained of new methods have so completely revolutionized this branch of industry, anil given us such a mastery over this material, enabling us to apply it to such new uses, that for the future the real Age of Iron will date from the i)resent century. The knowledge of the arch as a method of construc- tion with stone or brick — both of them materials aptly fitted for resistance under pressure, but of comparatively no tensile strength — enabled the Romans to surpass all (7) PHCENIXVILLE BRIDGE- WORKS, nations that had preceded them in the course of his- tory, in building bridges. The bridge across the Dan- ube, erected by Apoiiodorus, the architect of Trajan's Cohunn, was Vhe largest bridge built by the Romans. It was more than three hundred feet in height, com- posed of twenty-one arches resting upon twenty piers, and was about eight hundred feet in length. It was after a few years destroyed by the emperor Adrian, lest it should afford a means of passage to the barbarians, and its ruins are still to be seen in Lower Hungary. With the advent of railroads, bridge-building became even a greater necessity than it had ever been before, and the use of iron has enabled engineers to grapple with and overcome difficulties which only fifty years THE LYMAN VIAUUL T. ago would have been considered hopelessly insurmount- able. In this modern use of iron advantage is taken of its great tensile strength, and many iron bridges, over which enormous trains of heavily-loaded cars pass hourly, look as though they were spun from gossamer threads, and yet are stronger than any structure of wood or stone would be. Another great advantage of an iron bridge over one constructed of wood or stone is the greater ease with wh! jh it can, in every part of it, be constantly observed, and every foiling part replaced. Whatever material may be used, every edifice is always subject to the slow disintegrating influence of time and the e.-ments. In every such edifice as a bridge, use is a ] ocess of constant weakening, which, if not as constant! guarded against, must inevitably, in time, lead to its destruction. In a wooden or stone bridge a beam affected by dry rot or a stone weakened by the efi'ects of frost may l'-; hidden from the inspection of even the most vigilant observer until, when the process has gone far enough, the bridge suddenly gives way under a not unusual strain, and death and disaster shock the community into a sense of the inherent defects of these materials for such structures. The introduction of the railroad, has brought about also another change in the bridge-building of modern times, compared with that of all the ages which have preceded this nineteenth century. The chief bridges of ancient times were bui!.; uj great public conveniences, upon thoi (highways over which there was a large amount of travel, and consequently were near the cif'es or com- mercial centres which attracted such travel, and were therefore placed where they were seen by great num- bers. Now, however, the connection between the chief commercial centres is made by the railroads, and these penetrate immense distances, through compara- tively unsettled districts, in order to bring about the needed distribution; and in consequence many of the great railroad bridges are built in the most unfrequented spots, and are unseen by the numerous passengers who traverse them, ur:onscious that they are thus easily passing over specimens of engineering skill which sur- PHCENIXVILLE BRIDGE-WORKS. , lest rians, T- came efore, rapple years pass, as objects of intelligent interest, many of the sights they may be traveling to see. The various processes by which the iron is prepared to be used in bridge-building are many of them as new as is the use of this material for this prrpose, and it will nLAST-Fl'RNACr.S. not be amiss to spend a few moments in examining them before presenting to our readers illustrations of some of the most remarkable structures of this kind. Taking a train by the Reading Railroad from Philadelphia, we arrive, in about an hour, at Phcenixville, in the Schuylkill Valley, where the Phoenix Iron- and Bridge-Works are situated. In this establishment we can follow the iron from its original condition of ore to a finished bridge ; and it is the only es- tablisliment in this country, and most probably in the world, wliere this can be seen. These works were established in 1790. In 1827 they came into the possession of the late David Reeves, who by his en- ergy and enterprise increased their capacity to meet the growing demands of the time, until they reached their present extent, employ- ing constantly over fifteen hundred hands. The first process is melting the ore in the blast- furnace. Here the ore, with coal and a flux of lime- stone, is piled in and subjected to the heat of the fires. driven by a hot blast and kept burning night and day. The iron, as it becomes melted, flows to the bottom of the furnace, and is drawn off below in a gloiving stream. Into the top of the blast-furnaces the ore and coal are dumped, having been raised to the top by an elevator worked by a blast of air. It is curious to notice how slowly the experience was gathered from which has resulted the ability to work iron as it is done here. Though even at the first settlement of this coun- try the forests of England had been so much thinned by their consumption in the form of charcoal in her iron industry as to make a demand for timber from this country a flourishing trade for the new settlers, yet it was not until 161 2 that a patent was granted to Simon Sturtevant for smelting iron by the consumption of bituminous coal. Another patent for the same invention was granted to John Ravenson the next year, and in 1619 another to Lord Dudley; yet the process did not come into general use jntil nearly a hundred years later. The blast for the furnace is driven by two enormous engines, each of three hundred horse-power. The blast used here is, as we have said, a hot one, the air being heated by the consumption ofthe gases evolved from the material itself. The gradual steps by which these successive modifications were intro- duced are an evidence of how slowly industrial processes nUMPlNC. OKK AND COAI. INTO llI.AST-Fl'RNACKS. 1..V '-"^n perfected by the collective experience of gene- rations, and show us how much we of the present day owe to our predecessors. From the earliest times, as among the native smiths of .Vfrica to-day, the blast of a bellows has been used in working iron to increase the heat ofthe combustion by a more plentiful supply of oxygen. The 10 PHCENIXVILLE BRIDGE- WORKS. liLKVATlJK. blast-furnace is supposed to have been first used in Bel- gium, and to have been introduced into England in 1558. Next came the use of bituminons coal, urged with a blast of cold air. But it was not until 1829 that Neilson, an Englishman, conceived the idea of heating the air of the blast, and car- ried it out at t h e Muirkirk furnaces. I n that year he obtained a l)atent for this process, a n d found that he could from the same quantity of fi'*' make three times as much iron. His patent mad •"''• M. The view of the engines which pump the blast will give an idea of the immense power which the Phcenix company has at command. Twice every day the fur- nace is tapped, and the stream of liquid iron flows out into moulds formed in the sand, making the iron into pigs — so calleil from a fancied resem- blance to the form of these animals. 'I'his makes the first proce.ss, and in many smelt- ing establish- mei.cs this is all that is done, the iron in this form being sold and entering into the general consumption. The next i)rocess is "boiling," which is a modifica- tion of "puddling," and is generally used in the best iron-works in this country. The process of puddling was invented by Henry Cort, an Englishman, and patented by him in 1783 and 1784, as a new process for ' ' shing- ling, welding, and man- ufacturing iron and steel into bars, plates, and rods of purer quality and in larger quantity than heretofore, by a more effectual applica- tion of fire and ma- chinery." For this invention Cort has been called "the finthcr of the iron-trade of the British nation," and it is estimated that his in- vention has, during this century, given employ- ment to six millions of persons, and increased the wealth of Great Britain by three thousand millions of dollars. In his experiments for perfecting his process Mr. Lort spent his fortune, and though it proved so valuable, he died poor, having been involved by the ^^overnment in a lawsuit concern- ing his patent, which beggared him. Six years before PHOiNlXVILLE BRIDGE-WORKS. II his death, the government, as an acknowledgment of their wrong, granted him a j early pension of a thou- sand dollars, and at his death this miserly recompense was rediK ' to his widow, to six hinidred and twenty- five dolla'j. When iron is simply melted and run into any mould i t s texture i s granular, and it is so brittle as to be quite unreliable for any use requir- ing much tensile strength. The process of pud- dling consisted in stirring the molten iron run out in a puddle, ' and had the ef feet of so chang- ing its atomic arrangement as to render the process of rolling it more efficacious. The ,-.o';ess of boiling is considered an improvement upon this. The boiling- furnace is an oven heated to an intense heat by a fire urged with a blast. The cast-iron sides are double, and a constant circulation of water is kept passing tlirough the chamber thus made, in order to preserve the struc- ture from fusion by the heat. The inside is lined with fire-brick covered with metallic ore and slag over the bottom and sides, and then, the oven being charged with the pigs of iron, the heat is let on. The i)igs melt, and the oven is filled with molten iron. The puddler constantly stirs this mass with a bar let through a hole in the door, until the iron boils up, or "ferments," as it is called. This fermentation is caused by the combustion of a portion of the carbon in the iron, and as soon as the excess of this is consumed, the cinders and slag sink to the bot- tom of the oven, leaving the semi-fluid mass on the top. Stirring this about, the puddler forms it into balls of such a size as he can conveniently handle, which are taken out and carried on little cars, made to receive them, to "the squeezer." CAKKYINi; THU IKON UALLS To carry on this process properly requires great skill and judgment in the puddler. The heat necessarily generated by the operation is so great that very few persons have thp physical endurance to stand it. So great is it that the clothes upon the person frequently catch fire. Such a strain upon the physical powers naturally leads those subjected to it to indulge in excesses. The perspiration which flows from the puddlers in streams while engaged in their work is caused by the natural effort of their bodies to pre- serve themselves from injury by keeping their normal temperature. Such a consump- tion of the fluids of the body causes great thirst, and the exhaustion of the labor, both bodily and mental, leads often to the excessive use of stimulants. In fact, the work is too laborious. Its conditions are such that no one should be subjected to them. The necessity, however, for judgment, experience, and skill on the BOILlNG-FUKNACr. RtlTARV SgllEEZFH. part of the operator has up to this time prevented the introduction of machinery to take the place of human labor in this process. The successful substitution in modern times of machines, for jjerforming vprin-.^ operations which formerly seemed to require the intel- ligence and dexterity of a living being for their execu- tion, justifies the expectation that the study now being given to the organization of industry will lead to the invention of machines whicli will obviate the necessity for human suffering in the process of puddling. Such a consummation would be an advantage to all classes concerned. The attempts which have been made in this direction have not as yet proved entirely successful. In the squeezer the glowing ball of white-hot iron is placed, and forced with a rotary motion through a 12 PHCENIXVILLE BRIDGE-WORKS. spiral passage, the diameter of which is constancy di- minishing. Tlie eff' I t of tliis operation is to squeeze all the slag and cinder out of the ball, and force the iron to assume the shape of a short thick cylinder called "a bloom." This process was former- ly performed b y striking the ball of iron repeatedly with a tilt-hammer.' The bloom isnov re-heated • and sub- jected to the process of rolling. "The rolls" are heavy cylinders of cast- iron placed almost in contact, and re- volving rapidly by steam-power. The bloom is caught be- tween these rollers, and passed back- ward and forward until it is pressed into a flat bar, ave- raging from four to six inches in width, and about an inch and a half thick. These bars are then cut into s li o r t lengths, piled, heated again in a furnace, and re-rolled. After going througli this process they form the bar iron of commerce. From the iron "educed into this form the various parts used in the construction of iron bridges are made by being rolled into shape, the rolls through which the ■ I'lHiTii; ■^i'iiiii''.; various parts pass having grooves of the form it is desired to give to the pieces. T h e s e rolls, when they arc driven by steam, obtain this generally from a boiler placed over the heating- or puddling-furnace, and heated by tlie waste gases from the fun. ace. This ar- rangement was first made by John Griffie, the super- intendent of the Phoenix Iron-Works, under whose COLI> SAW direction the first rolled iron beams over nine inches deep that were ever made were produced at these works. The process cf rolling toughens the iron, seeming to draw out its fibres; and iron that has been twice rolled i s considered fi t for ordinary uses. For the various parts of a bridge, however, where great toughness and tensile strength are necessary, as well as uniformity of tex- ture, the iron is rolled a third time. The bars are there- fore cut again into pieces, piled, re- heated, and rolled again. A bar of iron which has been rolled twice is formed from a pile of fourteen separate pieces of iron that have been rolled only once, or "muck bar," as it is called ; while the thrice-rolled bar "s made from a pile of eight separate pieces of do'ihle-rolled iron. If, therefore, one of the original pieces of iron has any flaw or defect, it will form only a hundred and twelftii part of the thrice-rolled bar. The uniformity of texture and the toughness of the bars which have been thrice rolled are so great that they may be twisted, cold, into a knot with- out showing any signs of fracture. The l)ar» of iron, wheth- er hot or cold, are , HOT SAW. sawn to the various required lengths by the hot or cold saws shown in the illustrations, which revolve with great rapidity. For the columns intended to sustain the compressive thrust of heavy weights a form is used in this esiablish- ment of their own design^ and to which the name of I- ' ' i PHCENIXVILLE BRIDGE-WORKS. »3 1^' I Kivr.riNi; A column. the " PhcEiiix column" has been given. They are tubes made from four or from eight sections rolled in tlie usual way and riveted together at their flanges. (See Plate XV.) When necessary, such column: ;,.v. joined together by cast-iron joint-blocks, with circular tenons which fit into the hollows of each tube. To join two bars to resist a strain of tension, links or e y e- bars are used from three t o six inches wide, and as long ns may be needed. At each end is an enlarge- ment with a hole to receive a pin. In this way any number of bars can be joined together, and the result of numerous experiments made at this establishment has shown that under sufficient strain they wiil part as )ften in the body of the bar as at the joint. The heads upon these bars are made by a process known as die- forging. The bar is heated to a white heat, and under a die worked by hydraulic pres- sure the head is shaped and the hole struck at one operation. Tliis method of joining by pins is much more relial)le than welding. The pins are made o f cold-rolled sliafting, and fit to a nicety. The general view of the machine-shop, which covers more than an acre of ground, shows the various ma- chines and tools by which iron is planed, turned, drilled, and handled as though it were one of the soft- est of materials. Such a machine-shop is one of the wonders of this century. Most of the operations per- formed there, and all of the tools with which they are done, are due entirely to modern invention, many of tliem within the last ten years. By means of this aj)- plication of machines great accuracy of work is obtained, and each part of an iron bridge can be exactly dupli- cated if necessary. This method of construction is entirely American, the English still Iniilding their iron FUKNAfE AND IIYlJHAl'Llf bridges mostly with hand-labor. In consequence also of this method of working, American iron bridges, despite the higher price of our iron, en successfully compete in Canada with bridges of English or Belgian construction. The American iron bridges are lighter than those of other nations, but their absolute strength is as great, since the weight which is saved is all dead weight, and not necessary to the solidity of the struc- ture. The same difference is displayed here that is seen in our carriages with their slender wheels, com- pared with the lumbering heavy wagons of European construction. Before any practical work upon the construction of a bridge is begun, the data and specifications are given, and a plan of the structure is drawn, whether it is for a railroad or for ordinary travel, whether for a double or single track, whether the train is to pass on top or below, and so on. The calculations and plans are then made for the use of such dimensions of iron that the strain upon any part of the structure shall not exceed a certain maximum, usually fixed at ten thousand pounds to the square inch. As the weight of the iron is known, and its tensile strength is estimated at sixty thousand pounds per square inch, this estimate, which is techni- cally called "a factor of safety" of six, is a very safe one. In other words, the bridge is planned and so constructed that i n supporting its own weight, together with any load o f locomo t i ves or cars which can be placed upon it, it shall not be sub- jected to a strain over o n e - s i X t h of i t s estimated strength. After the plan is made, working drawings are pre- pared and the process of manufacture commences. The eye-bars, when made, are tested in a testing- machine at double the strain which by any possibility they can be put to in the bridge itself. The elasticity of the iron is such that, after beirg submitted to a ten- sion of about thirty thousand pounds to the square inch, it will return to its original dimensions; while it is so tougii that the bars, as large as two inches in diameter, can be bent double, when cold, without showing any sigr.s of fracture. Having stood these tests, the parts Of the bridge are considered fit to be used. When completed, the parts are put together or •f 14 PH(.ENIXVILLE BRIDGE- WORKS. "asseniblcil," as the technical phrase is, in order to see that tiiey are right in length, etc. Then they are marked with letters or numbers, according to the work- ing jiian, and shipped to the spot where the bridge is to be permanently erected. Before the erection can be begun, however, a staging or scaffolding of wood, strong enough to support the iron structure until it is finished, has to be raised on the spot. When the bridge is a large one, this staging is of necessity an im- portant and costly structure. An illustration on the next page shows the staging erected for the support of the New River bridge in West Virginia, on the line of the Chesapeake and Ohio Railway, near a romantic spot known as Hawksnest. About two hundred yards below this bridge is a waterfall, and while the staging was still in use for its construction, the river, which is very treacherous, suddenly rose about twenty feet in a few hours, and became a roaring torrent. The method of making all the parts of a bridge to fit exactly, and securing the ties by pins, is peculiarly American. Th.e plan still followed in Europe is that of using rivets, which makes tiie erection of a bridge take much more time, and costs, consecpiently, much more. A riveted lattice bridqe, one hundred and sixty VIKW OF MACHINK-Sllnl'. feet in span, would require ten or twelve days for its erection, wiiile one of the Pluenixville bridges of this size has been erected in ciglit and a half hours. The view of tlie Albany bridge will show the style which is technicall)- called a "tlirougii" bridge, having the track at the level of the lower chords. 'l"iiis view of the bridge is taken from the west side of tlie Hud- son, near the Delavan House in .Mbanv. The curved portion crosses the Albany basin, or outlet of the Erie Canal, and consists of seven spans of seventy-three feet each, one of sixty-tliree, and one of one hundred and ten. That part of tiie bridge which crosses the river consists of four spans of one hundred and eighty-five feet each, and a draw two hundred and seventy-four feet wide. The iron-work in this liridge tost about three hundred and twenty thousand dollars. The bridge over the Illinois River at La Salle, on the Illinois Central Railroad, shows the style of bridge technically called a "deck" bridge, in which the train is on tlie to]). This bridge consists of eighteen spans of one hmulred and sixty feet ea( h, and cost one hun- dred and eighty thousand dollars. Tlie bridge over the Kennebec River, on the line of the Maine Central Railroad, at .'Vugusta, Maine, is anotlier instance of a "through" bridge. It cost seventy-five thousand dollars, has five spans of one hundred ami eiglity-five feet each, and was built to rejilace a wooden deck bridge which was carried away by a freshet. The bridge on the Portland and Ogdensburg Rail- road which crosses the Saco River is a very general type of a through railway bridge. It < onsists of two spans of one hundred and eighty-five feet each, and PHiENlXVILLE BRIDGE- WORKS, >S ( ost twenty thousand dollars. The New River bridge in West Vir},nnia consists of two spans of two hiinda-d and fifty feet each, and two others of seventy-five feet each. Its cost was ahout seventy thousand dollars. .<) v^m».^^sm^sm. NliW KIVHR IIKIDGR ON ITS STAGING. riie Lyman Viaduct, on the Connecticut Air-line dred and thirty-five feet high and eleven hundred feet Railway, at East Hampton, Connecticut, is one hun- long. limin.I-. AT AI.nAN\. These specimens will show the general chanicter of [ employed, hut its brittleness and unreliability have led the iron bridges ercted in this country. When iron : to its rejection for the main portions of bridges. E.\- ivas first used in constructions of this kind, cast iron was perience has also led the best iron-bridge-builders of i6 PHCENIXVILLE BRIDGE- WORKS. America to quite generally employ girders with parallel ton and bottom members, vertical posts (except at the ends, where they are made inclined toward the centre of the span), and tie-rods inclined at nearly forty-five degrees. This form takes the least material for the re- quired strength. The safety of a bridge depends qnite as much upon the design and proportions of its details and coiinec - Ill' .^*i LA bALLK IIKIW;!'.. tions as upon its general shape. The strain which will compress or extend the ties, chords, and other parts can be calculated with mathematical exactness. But the strains coming upon the connections are very often indeterminate, and no mathematical formula has yet been found for them. They are like the strains which come upon the wheels, axles, and moving parts of carriages, cars and machinery. Yet experience and judgment have led the best builders to a singular uni- formity in their treatment of these parts. Each bridge has been an experiment, the lessons of which have been studied and turned to the best effect. BKIUGK AT AUGUSTA, MAINI!. There is no doubt that iron bridges can be made perfectly safe. Their margin is greater than that of the boiler, the axles, or the rail. To make them safe, European governments depend upon rigid rules, and careful inspection to see that they are carried out. In this country government inspection is not relied on with such certainty, and the spirit of our institutions leads us to depend more upon the action of self-interest and the inherent trustworthiness of mankind when in- dulged with freedom of action. Though at times this confidence may seem vain, and "rings" in industrial pursuits, as in politics, appear to corrupt the honesty which forms the very foundation of freedom, yet their influence is but temporary, and as soon as the best PHCENIXVILLE JiRIDGE- WOUk'S. »7 public sentiment becomes convinced of the need for their removal their influence is destroyed. Such evils are necessary incidents of our transitional movement toward an industrial, social, and political organization in which the best intelligence and the most trjstworthy honesty shall control these interests for the best advan- tage of society at large, in liic meanliinc, tiie best ^ taiiily do not desire to waste their i.ioney or to render security the self-i for the safety of iron bridges is to be found in -interest of the railway corporations, who cer- themselves liable to damages from the breaking of their bridges, and who consequently will employ for such I'HtlCNIX WiiUKS constructions those whose reputation has been fairly earned, and whose character is such that reliance can be placed in the honesty of their work. Experience has given the world the knowledge needed to build 3 bridges of iron which shall in all possible contingencies be safe, and there is no excuse for a penny-wise-and- pound-foolish policy when it leads to disaster. Edward Howland. APPENDIX No. 2. LOADS AND STRAINS OF BRIDGES. A paper presented by JOHN GRIFFEN and THOS. 0. OLABKE, OivU Engineen, memben of the American Society of Oivil Engineers, at tlie Fourth Annual Oonrention of the Society, held at Ohioago, June 6 and 6, 1872. How to obtain uniformity of strength is the problem to be solved by the design of iron railway bridges. The strength of the weakest bridge, and of tlie weakest part of that bridge, measures the strength of all the bridges on a line of railway. The breaking of a single floor beam may wreck a train, and kill and wound many persons; and it is no consolation to know that all the other floor beams, tie rods, etc., of other bridges of the same line, have a superabundance of strength. The stn^nglh of a bridge results from the following conditions: — The heaviest loads to which it can be subjected. The maximum strains resulting from those loads. The sizes of the tensile and compressive members, and hence their strains per square inch of area. The available strength of those members depending upon — First. The quality of the iron of which they are made. Second. The cross-section of the struts. Third. The mode of forming the connections. Errors of design have been made in respect to all these points. First. A uniform load per lineal foot has been as- sumed for all spans, short and long alike, while the actual load is greater for short, and less for long, spans, and is always in excess of the general load upon certain parts, such as floor beams. Second. No distinction has been made between the effects of the dead load of the structure and the moving or live loac f trains, suddenly applied and accom- panied by s ^cks and vibrations. Third. The margin of safety between the allowed strain and the disabling limit of the iron has been over- estimated, as the margin of safety of the weakest part measures that of the whole. Fourtli. Sufficient distinction has not been made in specifications between a tough and elastic iron, and a hard and brittle quality, if the ultimate breaking strength of both were alike. Fifth. The strains allowed upon compressive mem- bers are not based upon any definite knowledge of their ultimate powers of resistance. These points will be considered in turn, and sugges- tions will be made toward a practice which shall result in uniformity of strength in all lengths of span, in all (18) parts of every span, so that one part shall not give way before another. The standard of strength must finally be determined by the engineer for each particular case. It would be useless to lay down any rules upon this point. F» 12 6 ft. 6 in. 25,264 6 ft. 6 in. 45,400 ■3 43 ft. 10 in. 125,300 8 ft. 40,320 53 ft. 6 in. 1 1 2 ,000 16 >7 New York Central, standard pa-ssenger and freight 7 ft. 6 in. 40,000 49 ft. lOO.fKX* 7 ft. 6 in. 16,50*1 ti» 25,0 X) 44 ft. 33,otKi to 50,t)tw 20 ft. 4 ft. 6 in. CLASS No. 4.— LOADED CARS. Pennsylvania Railway, sleeping and passenger ca Pennsylvania Railway, box freight cars Reading, long coal cars Lehigh Valley, short coal cars Pullman palace and steeping cars 57,000 64 ft. 2 in. 42,0(X> 3>ft. 40,0110 22 ft. 19, OCX) ■3 ft. 7 I /k*! 75 ft. 890 ■355 1818 1461 954 PHCENIXVILLE BRIDGE-WORKS. 23 Table No. 2. WEIGHT IN POUNDS PER FOOT RUN OF TRACK, FOR DIFFERENT SPANS AND KINDS OF TRAINS. Length of Spans in Feet. UiuIlt 13.. 12 to 17.. 17 to 25.. 25 to 8^.. 8j In iKi.. tlo.. 125.. 150.. 175.. 2(X).. 225.. 250.. 3974 1950 »943 1 92 'J 1907 FREIGHT TRAIN. Cars (No. \q\ drawn by I En- gine (No, 8), 2405 2262 2111 2^,65 ■.Q22 1S64 i8u9 >733 1679 1638 1870 1809 1740 1710 1665 1631 1603 1363 1533 1510 a. PASSENGER TRAIN. Cars (No. 22) drawn by i En- gine (No, 16). 1481 1418 13.1 ■ 285 1344 I31I 1186 II47 iiao I too Table No. 3. RATES OF DEAD TO LIVE LOAD, FOR DIFFERENT SPANS. LENr.Tii OP Spans in Fukt. Under 12 12 to 17. 17 to 25, 25 to 50. 50 to 83. 100. llu. 125. 150, ■75. 2on. 225, 250, 300, 350 400. DEAD LOAD LIVE LOAD ofHridge.Traci*, Rails, etc., of Coal Train TOTALLOAD, ■ itll 2 Engines, lbs , per foot. per foot. per foot. 500 5000 5500 55" 4000 4550 635 3500 4125 700 3000 3700 800 3CKXJ 3800 900 2500 3400 loco 243" 3430 ■■35 2365 3500 1.^25 2275 3500 1 }t)0 2200 35"" 15U0 2130 363" 1700 210" 381XJ 2000 2068 4068 1:400 2026 4426 3000 20UU 5000 400U 2000 6000 RATIO OF DEAD TO LIVE. "9 9' 12 88 ■ 5 85 ■9 81 21 79 26 74 3" 70 33 68 35 65 37 63 4^ 59 45 55 49 51 54 46 60 40 66 34 Table No. 4. DEAD AND LIVE LOAD PER FOOT, REDUCED TO EQUIVALENT DEAD LOAD. LiiNiiTH OF Spans in FiiUT. Under 12 12 to 17, 17 to 25. 25 tu 50. 50 10 83. 110. 125. IS". ■75. 200. 223. a, so. 30-3. 35"- 4"". <2 3. 4. De.adI.OADof Twice Live LOAD Sinn of cnlumns Ilridge, tic, per ft. of Coal Trail; 2 and 3, 1. 'Mng per ft. Lqnivalem Dead Lo.id per ft. S(X> 10,000 10,500 55" 8000 8550 (12 s 7cx)o 7625 700 6vxJO 6700 Sou 6000 66uo yoo 5«)0 '^ nxjo 48f)o "35 473" 5865 I2J5 4 5. SO 5775 1 ICKJ 44110 57>M I SOU 42(10 5760 I7ix> 4200 5900 2000 4136 6136 2400 4053 6453 3000 4000 7000 40U0 4000 89 I |5« q.. i ^ \ ,/ ■\, [\ \ / \ / / \.--' \ \ rt_ / znc \ / — Tin ~2 HE I aA ^ n A '% "■'1^:^ -xirr-" TsjJ. 1 o * OJ f^ ^ -• >;f * ',< • -»"— ^ ^* C4 V • ^^'i^^v^Jitl-'-S-j-NiL'Sir-v^ (-"""- ■■■■'■■■§> I |-. :v, u"i," r--"^"'- H H W K !-'''-r--' I ftt'i' <:•-. ^ »i 1 A^ ■> ^: ^£E r^ ;• .m ^^#% :il ■^^ha^iMaiSi §^ I' ^5S F\\'V ^^ I } ^ ^ >5 V c:?- ./ o «Si t« rJ^ ** '«» ■ — ,— ^ ^ i ^ «, •^ t *- f O ^M ">^ 1 ?» v^ s / / / ■/■--- V -r :n ^i; ]f!?; .' <■ € J .J i vO »J t o t«» 1 M 'I v ./ r Z^ i I ;l. ^ X 1 f 1 , h.i c y. // // umk I J I. ^> ^^ — e Tti n< .35 P ■^n ^ i. I- I- "i» i I j- -T I ,1 ImJuL <;>> ^ ? -3' ^S'^nc j, 3) ..^ s i ^,iiiiri*au rrrr. ^V. r-^ \ 4^ ■^. j.— p.>^/ >\: V- tM ^' ^'V— ^S^ € r- -Ijl S0^- ^ -^ 1 «-^ -i;^- ^ s ^ SI* Ij 'I ili- m .li i V ^ ? > 5 N i 9 I *i ( _j ( 1 ^-0 ^ y I At I 5 vv">^,r'K \ "A. .1 /■■ >l^ ^i I' \ •n o :^ ^ ;^ s» ^ o « •3 ^ i(k ^ ^ <<* i, 1 « •^ r« ^ nu ^ -d "^1 tX^-sa'-m fV^ b V V •* •^ ^ VKNKKK ^ *) ^ ^ ^ !j im II \ • \ 2 ^ C (1 » ^ ^ ^ V / ^<^ /' ,v' S s5r **==^^ o -^ i^ ^ '- ^ ^ t N- I ' \ 4 \.\ \ \ =-#'4^-— -i- \, ■ — ■ — ^- ,-*=■ ^^— =»• k^ > :^.=4 \ ^ S ^ \ \ N " * •?!. *S^ ^»4 ; ■"ilUHBHHff^^l^BI ; WB t li ^ ' Descripiivu vf I'oIudd.j W: 4 Meg. B* ('oliiiiinl 4 Sfg. B' " 1 4 Seir. A '* : < 4 Me|(. A tt 4 SeK. A »( 4 St'g. A tk •4 Heg. B' *• t4 Seg. B' • • {4 Seg. (' \ kl 4 Seg. V kt "This Column af 26,712 lbs. per - inch tl.enjjtli of Colui I'Vhh Column ha holes. 'Hlt»»3a.Hjm > isT ■an 1 llc8(ri|i(iou »r t'oluDD. 4 Seg. B> Coliiiiin D 4 Seg. B' *• C V. ; ' : i i DIAMKTKK. r \ 1 i Arvn or Pl«it4tn or Hy«lrnuliv Pr«M, aau „ iNvhc*. 2 a 9 ■a o 1 I i4 ? a! S Si 11 I 4 Seg. A Ji 4 Meg. A J' 4 Seg. A A 4 Seg. A It *4 Seg. B' E t4 Seg. B« H H Se»- t' L 4 Seg. V K 8" 4 29-32" 5.1" 8'' 8" 4 29-82" 5.1" 8'' 4" 3 21-3a"i4 '1-32" « 5-1(1' 4" 8 21-82" 4 ll-8',>" « 5-1(1' 4" 8 21-82" 3 81-32" 5i" 4" 3 21-33" 3 31-83" 5i" E aS'O:]" 4i" 5 11-82" 8 WO" 4i" 5j{" 8 L 23'4J" 7|" 7 13-1(!" ILl" K 3'.>'8i" 7 3-3!.' '■ T 19-33" 10-3 1.4 pressure, and in this crippled state, failed under a total pressure of 156,000 lbs., or 26,712 lbs. per ^ inch. holes. li.ength of Column proper, J3'ii"— Radius of senti-spheric Ca?iiings, 5',"— making length over all, 24^o'\ i'rhis Column had thirtv-five 0- (6'' 9(6"° punched holes 8 " apart in each of .• opposite Segments, and yielded in the dire(flion of a plane through the punched -^^MMswwwinipwiw ^' '-'WP'JVWillt'';