MEDICAL 
 
A MANUAL OF MICROSCOPIC MOUNTING. 
 
 : - ... 
 
t 
 
 VI 
 
 Wooster, Ohio. 
 
PLATE XII. 
 
 1. Cornuspira. 
 
 2. Spiroloculina. 
 
 3. Triloculina. 
 
 4. Biloculina. 
 
 5. Peneroplis. 
 
 6. Orbiculina (cyclical form) 
 
 7. Orbiculina (young). 
 
 8. Orbiculina (spiralform). 
 
 9. Lagena. 
 
 10. Nodosaria. 
 
 11. Cristellaria. 
 
 12. Globigerina. 
 
 13. Polymorphina. 
 
 14. Textularia. 
 
 15. Discorbina. 
 
 16. Polystomella. 
 
 17. Planorbuliua. 
 
 18. Rotalia. 
 
 19. Nonionina. 
 
A MANUAL 
 
 OF 
 
 MICROSCOPIC MOUNTING 
 
 WITH NOTES ON THE 
 
 COLLECTION AND EXAMINATION OF OBJECTS 
 
 BY 
 
 JOHN H. MARTIN, 
 
 MEMBER OF THE SOCIETY OF PUBLIC ANALYSTS ; 
 FELLOW OF THE SOCIETY OF AUTS ; AUTHOR OF MICROSCOPIC OBJECTS, ETC. 
 
 SECOND EDITION, 
 
 4 
 
 ^ 
 
 c 
 
 LONDON : 
 J. AND A. CHURCHILL, NEW BURLINGTON STREET. 
 
 1878. 
 [The right of translation is reserved.} 
 
 K 
 
1 v?O 
 
 9*78 
 
 TO 
 
 DR. LIONEL S. BE ALE, M.B., F.R.S., ETC. 
 
 FELLOW OF THE JIOYAL COLLEGE OF PHYSICIANS, 
 
 PHYSICIAN TO KING'S COLLEGE HOSPITAL, 
 FELLOW OF THE MEDICAL SOCIETY OF SWEDEN, ETC., ETC. 
 
 23411 
 
PBEEACE TO EIEST EDITION. 
 
 Tins work is intended for the use of students and 
 lovers of the science of microscopy. I desire to 
 draw the attention of my readers to the value of 
 original and practical work; for if any one subject, 
 however small, is made by concentrated attention 
 to bear fruit to the worker, it will be found to 
 contain much that is new to the science. In micro- 
 scopic mounting the student must not be discouraged 
 at the failure of his first attempts, but gradually try 
 to acquire a knowledge of the principles, with the 
 manual dexterity necessary in their application. 
 The aim of this work is to supply the student 
 with a concise manual of the former, and to assist 
 his progress in the latter, as far as illustrations and 
 words render it possible. 
 
VI PREFACE. 
 
 The majority of the drawings have been done 
 by me, most of which are original. My thanks 
 are due to Dr. Lionel Beale, for the loan of 
 Pigs. 15, 61, 64, &c. ; and also to Drs. Smyth, 
 Matthews, Bloxain, and Rev. W. Lane; also Messrs. 
 Jordan, Hardwicke, Cotton and Johnson, Collins, 
 Wheeler, &c ; and to Messrs. Pardon and Son, 
 printers, Messrs. Butterworth and Heath, Miss 
 Powell, and others, for their faithful rendering 
 in the engravings my ideas as drawn on the 
 wood, &c. 
 
 JOHN H. MARTIN. 
 
 -WEEK STREET, MAIDSTONE. 
 August, 1872. 
 
PREFACE TO SECOND EDITION. 
 
 The favourable reception which the first edition 
 of this work received, both in this country and 
 America, has induced me to spare no exertion to 
 render the second, worthy of the continued confidence 
 of the profession, as a guide to the practitioner, and 
 a text book for the student. The whole work has 
 been subjected to careful revision, and without 
 unduly extending its limits, pains have been taken 
 to allow nothing of importance to escape attention. 
 Many of the wood-cuts have been re-drawn, and 
 others added, together with much important new 
 matter. My cordial thanks are due to Dr. Lionel 
 Beale, E.R.S., &o.; Dr. Carpenter, E.R.S., L.L.D., &c. 
 for loan of plates ; also to my friend Dr. T. A. Kennedy 
 for his kind suggestions during the progress of the 
 
Vlll PREFACE. 
 
 work ; and to the printer Mr. Dickinson for the able 
 manner in which he has carried it through the press. 
 Trusting that my labours will meet the approval of 
 my friends and brother scientists I with pleasure leave 
 it to speak for itself. 
 
 JOHN H. MAETIN. 
 
 MICRO-ASSAY LABORATORY, 
 YORK CHAMBERS, 
 
 ADELPHT, 
 
 LONDON, W.C. 
 
 March, 1878. 
 
CONTENTS. 
 
 CHAPTER I. 
 
 PAGE 
 APPARATUS, ETC., NECESSARY FOR MICROSCOPICAL RESEARCH 1 
 
 CHAPTER II. 
 
 THE DRY METHOD OF PREPARATION OF VARIOUS MICROSCOPICAL STRUCTURES 54 
 
 CHAPTER III. 
 
 THE PREPARATION BY THE CANADA BALSAM AND DAMMAR PROCESSES ... 80 
 
 CHAPTER IV. 
 
 THE PREPARATION BY THE FLUID AND SEMI-FLUID MEDIUMS ... ... 94 
 
 CHAPTER V. 
 
 A GENERAL SUMMARY OF THE VARIOUS METHODS OF MOUNTING, WITH 
 
 MANY ADDITIONAL NOTES ... ... ... ... ... ... ... 106 
 
 CHAPTER VI. 
 
 ON THE COLLECTION AND ROUGH PRESERVATION OF SPECIMENS, WITH 
 
 NOTES ON THE CLASSIFICATION OF OBJECTS ... ... ... ... 139 
 
 CHAPTER VII. 
 
 METHODS OF EXAMINATION OF ORGANIC AND INORGANIC SUBSTANCES, 
 
 WITH TESTS FOR ADULTERATIONS . .. 159 
 
 APPENDIX. 
 
 VARIOUS USEFUL RECEIPTS, ETC. ,. 183 
 
A MANUAL OF MICROSCOPIC MOUNTING. 
 
 CHAPTER I. 
 
 APPARATUS NECESSARY FOR MICROSCOPICAL RESEARCH. 
 
 1. IN a work like this, which will chiefly treat of 
 various methods of mounting, a description of different 
 microscopes, &c., would be foreign to the subject. I 
 therefore leave this by remarking that good working 
 microscopes can now be purchased for about 5 each, 
 many of which contain apparatus sufficient for the 
 use of a beginner. 
 
 The apparatus to which I wish to draw the attention 
 of the reader chiefly consists of the section cutter, turn- 
 table, holding screw, apparatus for drying, dissecting, 
 bleaching, &c., most of which are necessary to the 
 student in conducting branches of microscopical 
 study. Works have been published including forms 
 of apparatus, but with the exception of those of 
 Dr. Lionel Beale, not many have been published of 
 late years. Some of the forms of apparatus have 
 been kindly lent, others which are chiefly original 
 have been used by the author in his own private study. 
 Drawings have also been added to the descriptions of 
 these various forms of apparatus, so as to make them 
 as useful as possible. The larger apparatus will be 
 explained first, and the smaller and miscellaneous 
 articles afterwards. 
 
 3 
 
2 A MANUAL OF 
 
 2. Section cutter, turntable (Matthews' s), holding 
 screw, apparatus for drying, dissecting, bleaching, &c. 
 The student must also add, buy, or make, as convenient 
 to him, the following articles : An air-pump ; propa- 
 gating or bee glasses, three or four ; the cup parts of 
 broken wine glasses the bottoms may also be used as 
 covers; dipping tubes made by holding glass tubes in 
 a gas jet until soft, and then drawing out to a fine point; 
 test tubes each of these may have a small dipping 
 tube placed in the cork, so as to reach to the bottom ; 
 forceps, one or two ; camel's and hog's hair pencils, 
 various sizes; scalpels, two or more; razor mounted in 
 wooden handle ; scissors, two pairs one fine pointed, 
 one common ; pneumatic trough, or a large globe or 
 dish for holding waste water, in which to wash slides, 
 test tubes, &c., or use the bottom of the dissecting slab 
 (Pig. 23) ; needles, three or four sizes, mounted in 
 small cedar handles (see Pig. 14) ; one large ditto, 
 ground down to a cutting edge (like a chisel), for 
 separating and cutting minute fibres, &c. ; twelve 
 collapsible tubes, for Canada balsam, &c. ; twelve 
 glass slips with hollowed centres, for use in analysis ; 
 a fine thread of spun glass, fixed in a handle, used for 
 isolating minute objects, such as diatoms, &c. ; spirit 
 lamp ; two hot plates, thick brass, 6 inches by 2 inches, 
 and 7 inches by 7 inches; tripods (two or three), or 
 a retort stand; American paper clips (these can be 
 obtained at most stationers) ; Liebig's extract of meat 
 jars, more especially the very small ones ; small white 
 porcelain cups (can be obtained of any artists' colour- 
 man) ; watch glasses ; wash bottle ; platinum wire ; 
 spoon and foil ; conical glasses, four or five ; eight to 
 twelve small bottles, with capillary orifices to hold 
 
MICROSCOPIC MOUNTING. 3 
 
 re-agents ; glass or porcelain funnel and stirring rods ; 
 small homoeopathic bottles, any quantity; writing 
 diamond ; fine saw, mounted in wooden handle ; hones, 
 used for grinding, &c. ; small tools, made of corundum 
 (of Mr. Lyon, 43, St. John's Square, London, E.G.) ; 
 crucibles, a few small ones ; files ; punches, two or 
 three ; small soldering rod ; hammer and wooden block 
 for punching, the under side of which is to be covered 
 with india rubber, to deaden noise ; pliers, two pairs, 
 one of them cutting; old knives; Pumphrey's ebonite 
 cells and zoophyte clips ; glass slips, 3x1 inch, half 
 gross at least ; thin glass 1 oz. circles, 1 oz. squares, 
 various sizes, as sold ; wire ; pill boxes ; small pins ; 
 cardboard, &c., &c. 
 
 The following chemicals, &c., will also be wanted : 
 Solution of gum Arabic in bottle, with a brush in the 
 stopper of the same ; glass bottle, with a glass tube 
 in the stopper, filled with Canada balsam, or the same 
 in collapsible tube; distilled water (with a lump of 
 camphor in it, to prevent any confer void growth, &c.) 
 in a large stoppered bottle; caustic potass (Kilo), 
 strength (by weight), one part potass to eight parts 
 water, in one pint bottle; distilled Canada balsam; 
 gum dammar in tube (see recipe) ; turpentine ; gly- 
 cerine; benzole; alcohol (pure), and also methylated 
 spirit ; essential oil of lemon ; syrup ; chloride of 
 calcium; lime water; silicate of potass; sulphuric 
 acid (stoppered bottle, labelled poison) ; hydrochloric 
 acid (stoppered bottle, labelled poison) ; acetic acid ; 
 marine glue ; caoutchouc cement (see recipe 5) ; Berlin 
 black (a varnish) ; gold size ; gutta percha ; Bell's 
 cement, &c. Also the following re-agents : Ether ; 
 acetic acid ; nitric acid ; sulphuric acid ; hydrochloric 
 
 B2 
 
A MANUAL OF 
 
 acid ; ammonia ; solution of potass ; solution of soda ; 
 oxalate of ammonia ; iodine solution ; nitrate of silver ; 
 nitrate of barium ; alcohol ; chromic acid ; test paper, 
 
 FIG. 1. 
 
 &c. ; and it is also advisable to keep a saturated solu- 
 tion of most of the common, salts, such as chloride of 
 zinc, &c. 
 
MICROSCOPIC MOUNTING. 
 
 3. Section Cutter. This may be bought at most of 
 the leading opticians, instrument makers, &c., the chief 
 things to notice being that the holding screw is strong, 
 and that it also has guides along which the knife or 
 razor slides ; but it is hardly necessary to buy one of 
 these instruments, as they may be made by the student 
 himself at a small cost. A sketch of a simple one that 
 will do its work is here given : Take a piece of box- 
 wood, or any other hard wood, plane it smooth and to 
 the size 3 inches by 4 inches then with a centre-bit 
 
 o 
 
 bore a hole exactly 2 inches deep in the centre of one 
 of the smallest sides ; 011 the opposite side also make a 
 hole 1^ inches deep, the diameter being at first 2 inches 
 and terminating at 1 inch (see Fig. 2), then bore a 
 small hole in the centre, so as to connect both holes. 
 Obtain one of Perry's music fasteners, Pig. 3, which 
 fix with marine glue to the under side, but allowing 
 the screw to pass through ; then cut a circular piece 
 of wood exactly the size of the tube, and a common 
 screw may be passed through each side of the section 
 cutter, so as to act as holding screws ; and on each side 
 
6 A MANUAL OF 
 
 of this hole place two strong wire guides, to support 
 the knife or razor in cutting the sections required (see 
 Eig. 4, which represents the top view) ; the wood, or 
 any other suhstance requiring to he cut, must then he 
 placed in the tuhe, the guard piece having heen pre- 
 viously put in ; the screw must then he slightly turned 
 to force the suhstance just ahove the guides (see chap- 
 ter ii.), then, with a knife, razor, or chisel, a section of 
 any thickness may he cut, according to the turning of 
 the hottom screw (see Fig. 2). If many sections 
 are to be cut, they may he embedded in a block of deal, 
 and sections cut with an iron plane, such as are used 
 by carpenters, &c. The advantages of the section 
 cutter represented here are being 
 easily made, light, portable, and 
 cheap. I have lately heard of a 
 new kind of section cutter, made 
 by a gentleman at Hastings, but 
 have not been able to obtain one 
 at present, but trust to do so soon. 
 Another form of section cutter in 
 general use, and to be obtained of 
 most opticians, is Fig. 4 A. It will 
 be seen from the drawing that the 
 
 instrument is very compact and 
 
 T FIG. 4 A. 
 
 useful . 
 
 4. The best turntable that can be obtained, and 
 which has nearly entirely superseded the one 
 formerly devised by Mr. Shadbolt, is simple in 
 the extreme (see Pig. 5). "It consists of two jaws of 
 the average thickness of a glass slide, -fths of an inch 
 wide, 2^ inches long. Each of these is pivoted on 
 the face of the turntable by a screw through its centre, 
 
MICROSCOPIC MOUNTING, 7 
 
 each screw being placed exactly equidistant from the 
 centre of the turntable, so that the jaws are separated 
 by a space as wide as an average slide, i.e., a full inch. 
 Outside of that space, on one side of the centre of one 
 of the jaws, is a wedge, fixed by a screw in such a way 
 as to be capable of motion in the direction of its 
 length by a slotted hole. This is all the machinery : 
 
 FIG. 5. 
 
 A B and c D are the two jaws, E is the wedge. On 
 placing a slip between the jaws, they probably at first 
 do not touch it. If the wedge be then pushed so as to 
 approximate B to c, the jaws move on their centres, 
 so that, however far B may be pushed towards (and 
 moving) c, the other end of c, i.e., D, is moved 
 exactly as much in the opposite direction until they 
 approach near enough to grasp the slide by its edges. 
 The length of the wedge must, of course, be such as 
 
8 
 
 A MANUAL OF 
 
 to provide for about one-eighth of an inch variation 
 in the width of slides. It will readily be seen that 
 the slip may be pushed in either direction eccentri- 
 cally lengthwise, so as to allow of the formation of any 
 number of cells (see Pig. 5), all of which must needs 
 be central as regards their width, if the instrument has 
 been accurately made, which is a very easy matter. 
 F represents the rest for the hand, which may be 
 turned aside on a centre at will." My own turntable 
 is worked by clockwork machinery, which gives 
 greater rest to the hand, and allows for more delicate 
 work to be performed than otherwise would be the 
 case if the same hand : i.e., right had the turning of 
 the wheel, as well as the making of the cells, &c., to do. 
 Any clockmaker would adjust a set of cog- wheels to drive 
 this turntable at a nominal price, say from 8s. to 12s. 
 
 5. Holding Screw. This piece of apparatus is best 
 made in a moveable form, so that it may be screwed 
 to any table (see Fig. 6) -and removed at will. The 
 
 figure explains its use without much further explana- 
 tion. It is used for holding pieces of bone, shell, 
 wood, glass, &c., whilst sections are cut with the fine 
 saw; also for holding the glass slip whilst these 
 sections of bone, &c., are being ground thinner by 
 the file. It may be considered as an indispensable 
 instrument to the microscopist. 
 
MICROSCOPIC MOUNTING. 
 
 9 
 
 6. Apparatus for drying Slides (see Pigs. 7, 8). A 
 great difficulty is often found in drying objects that 
 have been mounted in balsam or dammar; for even if 
 the balsam is good it takes a long time to dry pro- 
 perly, and the various plans that have been devised to 
 remedy this often fail in some point or other; for 
 instance, if the slides are placed on a tray and left in 
 an oven, when the fire is nearly out, to dry, succeeds 
 as far as it goes, but it will be found in practice that 
 they are often forgotten, and the fire is lit, and 
 perhaps valuable slides lost from over-baking; but this 
 difficulty is overcome by using an apparatus like Pig. 8. 
 Pig. 7 is a section of the same. It will be seen by 
 
 \ 
 
 / 
 
 this plan that the temperature can be entirely regu- 
 lated at will. The apparatus consists of a tin oven 
 open nearly from end to end in the centre, and having 
 
10 A MANUAL OF 
 
 a chimney with outlets for the hot air (see the direc- 
 tion of the arrows in Pig. 7) ; on each side of this 
 open centre are ranged a series of shelves made of 
 tin ; but for some delicate preparations a few shelves 
 might be of wood, as it is a bad conductor of heat. 
 These shelves, of course, can be taken in and out and 
 run on ledges prepared for them. Again, in the door 
 and the sides of the oven are a number of air-holes, 
 which can be covered with their accompanying flaps 
 when it is desired to increase or lessen the tempera- 
 ture. The oven may be made without these side 
 holes if desired, but it will be found better to have 
 them. The oven stands on four legs, and in the 
 centre of the bottom is a hole always open ; this hole 
 ought to be nearly the width of the oven. A gas 
 branch is used in the Pig. 7 ; but other forms of heat 
 can be used, such as from a large spirit-lamp, &c., 
 but of course the gas is best, as it can be regulated. 
 Any tinman would be able to make an oven from 
 these drawings ; the size, of course, depends upon the 
 number that the student would wish to dry at one time. 
 A useful size would be nine inches long, six inches 
 wide, four inches deep. If the student cannot afford 
 the cost of this apparatus, the next best plan is to 
 dry over gas. Take a piece of iron six inches long 
 by three inches wide, place this on one of the rings 
 of the retort stand (see Pig. 21), and under this bring 
 the gas jet. Get the right degree of heat by placing 
 a drop of balsam on a slip of glass, and if it does not boil 
 but only harden, the temperature is right. Eor drying 
 off the majority of objects, six slides maybe dried on the 
 plate at one time, occasionally changing their position. 
 After drying they may be finished as described in chap. iii. 
 
MICROSCOPIC MOUNTING. 
 
 11 
 
 7. Cell for the examination of Insects, 'Animalcules, 
 8fc. This form of cell (Eigs. 9, 10) will allow for the 
 investigation of nearly every form of minute life. 
 It may also he used for the formation of crystals 
 under the microscope (see Pig. 9) ; hut its chief use 
 will he for observing the action of the various gases on 
 
 <> 
 
 organic life. The cell may he made as follows : Cut 
 a piece of . ehony or hoxwood 3 inches long, 1J inches 
 wide, f th of an inch thick ; hore a hole -|ths of an 
 inch in diameter through the centre of this slip with 
 a centre-hit ; make a furrow or groove on each side 
 of this hole to receive two pieces of glass tuhing ^th 
 of an inch in diameter, the orifices of which shall 
 meet exactly in the centre of the hole (see Fig. 10) ; 
 with the cement (see recipe 6) fix the tuhes in this 
 position ; smooth all the edges whilst the cement is 
 warm, especially where it surrounds the orifices of the 
 tuhes leading into the large central hole ; then cut 
 
12 A MANUAL OJF 
 
 from a glass tube -fths of an inch outside diameter, two 
 pieces ^th of an inch thick; cement these into the hole, 
 one on each side of the slip, so that their edges may 
 come flush with the surface of the wooden slip ; on 
 the upper side of the wooden slip, and on each side of 
 the hole, fix two runners with a bevelled inner edge to 
 allow for a thin glass square of the exact size to slide 
 in (see Fig. 10) ; on the opposite side (see Fig. 9) fix 
 permanently with the india-rubber cement (recipe 5) a 
 thin glass circle -f ths of an inch in diameter to the steel 
 clip or spring (Fig. 9), so that the thin glass shall be 
 brought with great pressure against the opening of 
 the hole ; and to allow of the cell on this side to be 
 perfectly tight, an india-rubber ring is cemented to 
 the circle of thin glass. The slide is now complete for 
 all ordinary purposes ; but when it is desired to 
 observe the action of any of the various gases on 
 minute insect and other life, a different arrangement 
 of the cell is made. Take one of Pumphrey's ebonite 
 cells yfths of an inch in diameter, and slightly over 
 i^th in thickness ; rough the surface of this with a 
 file. Take another smaller cell, f ths of an inch in 
 diameter, and little over ^th in thickness ; cement 
 this to the larger cell with the india-rubber cement, 
 so that it may be exactly in the centre of the other; then 
 over the smallest hole, which is in the smallest cell, 
 cement with the same cement a thin glass cover half 
 an inch in diameter (see Pig 10, a) ; when thoroughly 
 dry, fill in the groove with the electrical cement 
 (recipe 6), and file the cell down into a truncated cone 
 shape (see Fig. 10, <?). Make two of these cells, and 
 when it is desired to make an observation on any 
 aiiinialculae, a small drop containing them is placed on 
 
MICROSCOPIC MOUNTING. 13 
 
 the inner side of one cell, and whilst kept in a hori- 
 zontal position on a table the wooden slip (Pig. 9) is 
 brought down on it. The spring containing the thin 
 glass circle being previously unscrewed and taken 
 off, the cell being of a wedge shape, will 110 doubt 
 fit tightly ; if it does not, it must be 
 cemented into this position with the aid 
 of electrical cement (recipe 6) ; the 
 other cell must be placed in the other 
 hole and the glass brought down upon 
 the drop of water, so as to retain it 
 between the thin glasses by the aid of 
 capillary attraction. If these cells are 
 found to be of too large diameter to 
 allow of their being brought sufficiently 
 near to each other, the diameter of each 
 truncated cone-shaped cell (Fig. 10 c) 
 must be reduced by filing ; they may 
 then be brought as near together as desired ; but of 
 course this depends upon the diameters of the cells. 
 When it is desirable to observe larger objects than 
 these cells will allow of, the orifices of the tubes 
 leading into the large cell must be closed with 
 cork, or what is still better, a round stick of cedar 
 wood run into the tubes from the outside ; these 
 may also be used for cleaning the tubes. But if 
 it is desired to keep the object alive in water for 
 some hours, a fine wire netting or mesh must be 
 kept over the orifices of the tubes leading into 
 the cell ; a constant stream of water may then be 
 directed through the cell, beginning at the tube on 
 the right hand of Pig. 10 (see the direction of the 
 arrows and flowing out at the opposite tube). India- 
 
A MANUAL OF 
 
 rubber tubing is used to connect this cell either with 
 the reservoir of water on the shelf (see Pig 24), or 
 with the gas holder (see Pig. 17). Gas may be 
 passed through the cell exactly in the same way as 
 water ; but if the living object is contained in water, 
 an india-rubber stopper must be placed over the outer 
 orifice of the left-hand tube (see Pig. 10), which is 
 kept in its place by a screw flap. This is done to 
 allow of the water contained in the cell to be 
 thoroughly saturated with the gas under pressure; but 
 for all dry living specimens it is generally unnecessary 
 to do this, as the gas may be passed through the cell 
 freely flowing out at the other tube. Some crystals 
 may also be made in this cell, and the process of their 
 formation observed under the microscope. Place 
 between the two truncated cone-shaped cells a drop of 
 hydrochloric acid (HC1) ; open the outer orifice of the 
 left-hand tube by removing the india-rubber stopper ; 
 then connect the other tube with a retort containing 
 ammonic chloride (NH 4 C1) and quicklime (CaO) ; 
 place this retort in a retort stand (see Pig. 28), and 
 subject it to a moderate heat over a spirit-lamp or a 
 gas-jet, when the ammonia gas is given off freely. 
 In using this and all other gases, with the exception 
 of oxygen and hydrogen, let the waste tube, which is 
 fixed on to the left-hand glass tube (Pig. 10), be con- 
 ducted, if possible, into the outer air through a small 
 hole in the window of the room. As the ammonia 
 passes through the cell it mixes with, and has an 
 affinity for, the hydrochloric acid which is in the 
 cell, and gradually crystals of ammonic chloride 
 (NH 4 C1) are formed. The process of their formation is 
 of an exceedingly interesting character, they having 
 been formed from the union of gases ammonia, 
 
MICROSCOPIC MOUNTING. 
 
 15 
 
 chlorine, and hydrogen the molecules of which are 
 of course invisible. 
 
 8. Bleaching Apparatus (Pig. 11). This piece 
 of apparatus does not require much description. 
 
 It consists of an analytical t 
 
 chemist's gas cylinder, 16 
 
 inches high, 2-J- inches in dia- 
 meter; this is open at the 
 top ; nearly at the bottom a 
 hole is drilled to receive a 
 piece of glass tubing (Pig. 11) ; 
 a test tube 8 inches long, 1^ 
 inches diameter is then sus- 
 pended with a rod and line 
 (see Pig 11). In the centre of 
 this open cylinder three discs 
 of wood, with holes bored 
 through them and fixed upon 
 a central rod, are then fitted 
 to the tube, so that they may 
 be taken out and in with plea- 
 sure, but at the same time fit 
 
 tightly ; the cylinder is then half filled with water 
 the objects that are required to be bleached have 
 been previously placed in the inside of the test-tube 
 upon one of the wooden perforated discs. Chlorine 
 gas (recipe 23) is then passed through the tube, 
 which must be at least half an inch up the test-tube ; 
 all the waste chlorine gas is absorbed by the water. 
 Many objects require to be slightly damped previous 
 to subjecting them to the action of this gas, other- 
 wise they will not bleach properly. 
 
 9. Test Bottle (Fig. 12). In micro-chemical 
 analysis of substances a drop only of any re-agent is 
 
16 
 
 A MANUAL OF 
 
 12. 
 
 required ; these bottles are used for this purpose. If 
 the student can afford it, he should have at least 
 twelve of these bottles ; they may be procured of Mr. 
 Browning, Strand, W.C. After they are 
 filled with the re-agent, a drop of glycerine 
 should be rubbed on the glass stopper to pre- 
 vent it sticking. 
 
 10. Wash Bottle (Pig. 13). This bottle 
 will be found very useful to the microscopist, 
 chiefly for washing delicate cuticles, &c., after 
 their separation from the cellular tissue; the 
 bottle is easily made. Take an ordinary 
 wide-mouth bottle, bore two holes in a cork 
 with the cork-borers used by chemists, then cut 
 two pieces of glass tubing, one about 4 inches long (it 
 is advisable to have this of a larger bore than the 
 
 other, see Eig. 13), the other 
 8 or 9 inches; the cut edges 
 of both pieces must be held 
 in the flame of the spirit- 
 lamp until smooth, and one 
 end of the longest piece 
 drawn out to a fine point, 
 which must be broken so as 
 to expose a very small hole 
 (see Pig 13) ; the tubes must 
 then be bent gradually in 
 the flame of the spirit lamp, 
 until the curves represented 
 in the drawing are gained, 
 after which they must be 
 cemented into the cork with 
 marine glue and a coating 
 of the india-rubber cement 
 
MICROSCOPIC MOUNTING. 
 
 17 
 
 (recipe 5) applied over all, so as to totally exclude 
 the air; the bottle may then be half filled with 
 distilled water, and used by blowing into the shorter 
 piece of tubing, when a fine stream of water will im- 
 mediately issue from the orifice of the other tube ; 
 this stream must then be directed upon the object to 
 be washed. A small kind of wash-bottle may also be 
 usad for injecting (see Chapter 5). 
 
 11. Dissecting Needles (Eig. 14). These form 
 some of the most useful tools that can be used in 
 microscopy; they are generally 
 fixed in cedar- wood handles, but a 
 crochet handle, made so that the 
 needles can be removed, will be 
 found the most useful. The needles 
 are ordinary needles made flexible 
 by holding them in the flame of a 
 spirit-lamp or gas jet, and then 
 bending them to the required shape. 
 Some useful forms are drawn at Eig. 
 14. To harden them make red-hot, = 
 then cool in oil, after which they | 
 may be fixed in the cedar handles, 
 or a stock of them kept in a small 
 box. Thick needles, if broken off v^ v 
 about one third of their length, and 
 the broken part made red-hot and /V 
 hammered flat and hardened, and then sharpened on a 
 hone, make very good knives for minute dissection ; 
 small chisels may also be made for cutting fibres, &c., 
 by grinding down a broken needle to a cutting edge (see 
 Eig. 14). The use of these small tools is chiefly 
 gained by experience. 
 
 c 
 
 I 
 
 t 
 
18 
 
 A MANUAL OF 
 
 12. Valentine's Knife (Kg. 15). These knives are 
 used for cutting thin sections of soft suhstances ; they 
 generally have two hlades flat on the inner side, but 
 lately they have been made with three, the middle 
 blade having nearly parallel surfaces; this will be 
 
 :,!* 
 
 jjmia&m 
 
 FIG. 15. 
 
 found much more useful than the older form, a 
 greater advantage being gained by its allowing of the 
 two sections to be opened and spread out so as to 
 form a larger surface for examination. Before using 
 this knife the blades must be dipped in warm water, 
 as when they are wet they cut much better. After it 
 has been used it should be well cleaned and wiped 
 with a soft handkerchief, and then with chamois 
 leather if necessary, for if any rust occurs on the 
 blades it will prevent in a great degree, their cutting 
 well. The instrument should be kept in a small and 
 separate case when not in use. 
 
 13. Gas-jet and Stand 
 (Pig. 16). This wood-cut 
 illustrates a useful form of 
 gas stand made of iron. 
 It will be found for all 
 ordinary purposes to be even 
 better than using a spirit- 
 lamp; but for testing, a 
 purer flame will be required, in which case the spirit- 
 lamp (Pig. 26) is the best. 
 
 FIG. 16. 
 
MICROSCOPIC MOUNTING. 
 
 19 
 
 14. Gas-holder (Eig. 17). Various gases which 
 are not soluble in water, may be collected in this 
 apparatus as follows : the 
 india-rubber tubing on the 
 right hand side of the en- 
 graving must be fixed to the 
 mouth of a retort (see Eig. 
 28), the gas is then gene- 
 rated and passed through 
 the tube into the holder 
 (the receiver in Eig 28 has 
 of course been previously 
 taken off) ; the hole where 
 the glass tubing enters the 
 holder (Eig. 17) must be, 
 well cemented over to pre- 
 vent any escape of gas f*f 17 ' 
 and when oxygen or any other gas that may be in 
 the holder is wanted, the cement must be loosened, 
 and the tube drawn up f of the height of the 
 jar, then re-cemented; the tubing fixed to the gas 
 cell, Eigs. 9, 10, page 11, and the weights applied 
 according to the pressure required, when the gas 
 will flow with an even and regular action. The 
 apparatus is made as follows : - - Take two large 
 confectioner's glass jars, one slightly larger than 
 the other ; to the top of the smaller one cement a 
 wooden hook (see the fig.) of such a size and 
 shape as to allow circular leaden or iron weights to 
 pass over it ; on the right side of this drill a hole in 
 the top of the glass jar ; into this hole cement a strong 
 cork previously bored to receive the piece of tubing, 
 which insert, and make air-tight with cement (if best 
 
 c 2 
 
20 A MANUAL OF 
 
 cork is used this is scarcely necessary) ; see Recipe 6 ; 
 on the left hand side of the stand fix a strong wire 
 or wooden supporter, from which suspend the inner 
 and smaller jar, which is done hy placing an 
 india-rubber band over the hook (see Pig. 17). 
 Although gas may he stored in this apparatus, it 
 is as well to make it when wanted. In changing 
 gases in the holder, say from oxygen to hydrogen, 
 great care should be taken that the smaller jar 
 should be well purified by washing before the other 
 gas is put in ; in practice it is as well to have three 
 or four of these gas holders if possible. For the 
 methods of making the various gases see Appendix, 
 Recipes 19, 20, 21, &c. 
 
 15. Woulff's Bottle (Pig. 18). This form of bottle 
 is generally used for generating and washing gases, 
 &c. ; thte india-rubber tubing is fixed to the glass 
 tube (which conducts the impure gas), the orifice of 
 which is carried beneath the water, and the pure 
 gas issues from the other and shorter glass tube, 
 
 and is carried by another piece of india- 
 rubber tubing into the gas-holder. The 
 wood-cut represents, not the washing of 
 a gas, but the generation of hydrogen 
 from zinc filings by the aid of sulphuric 
 acid (So 2 Ho 2 ) and water. This bottle 
 may also be used as a wash-bottle, in 
 FIG. is. which case the thistle tube A represents 
 
 the blowing tube, and B the tube for the issuing jet 
 
 of water. 
 
 16. Glass Tube drawn out (Pig. 19). This drawing 
 represents the method of drawing a glass tube to a 
 capillary hole or orifice, which is done by holding the 
 
MICROSCOPIC MOUNTING. 
 
 21 
 
 tube in the flame of a spirit-lamp; if a piece of 
 platinum wire lias been previously passed into the 
 
 FIG. 19. 
 
 tube, upon drawing it apart the wire will remain in 
 the glass, which forms a handle, and will be found a 
 useful tool for picking out cuticles, &c., after being 
 treated with nitric or other acids, as they have but 
 little action upon the platinum. The size of the hole is 
 of course regulated by pulling the tube apart either 
 slowly or quickly ; this is soon gained by practice. 
 
 17. Triangle for Testing, fyc. (Pig. 20). The 
 drawing shows how it is made, i.e.) of two pieces of 
 
 fig 
 
 21. 
 
 20. 
 
 iron wire inserted into a handle and twisted ; these 
 are again twisted with a shorter top piece of wire, 
 so as to form a triangle. It is chiefly used for holding 
 
22 
 
 A MANUAL OF 
 
 a piece of platinum foil or mica over the spirit-lamp 
 when it is required to test the organic or inorganic 
 nature of any ohject (Chapter 7) ; or in burning 
 diatoms and other silicious particles to a red heat. It 
 will also he found very useful for drying any ohject on 
 the thin glass covers. 
 
 18. Retort Stand and Gas-jet (Pig. 21). The 
 stand should he supplied with at least three or four 
 different sizes of rings to allow for the various vessels 
 that may he wanted ; the figure represents the process 
 of hoiling any substance in an evaporating dish over 
 the gas-jet. 
 
 19. Fine Saw for Cutting Sections (Pig. 22). 
 Watch-spring saws are sold for microscopical work; 
 
 FIG. 22. 
 
 but the best form of saw for cutting sections is made 
 like the drawing ; they may be procured at the large 
 tool shops. 
 
 20. Dissecting Slab with Bath for Waste Water, 
 8fc. (Pig. 23). The frame-work may be made of 
 
 deal or any other cheap wood, the size to be one foot 
 long, five inches wide, six inches high. Into the top 
 
MICROSCOPIC MOUNTING. 23 
 
 slab, which should be about one inch thick, a shallow 
 trough made of glass or slate glass being the better 
 of the two is embedded (see drawing) ; in the centre 
 of this a large hole is drilled to allow the waste 
 water to run into the bottom bath, which bath may 
 be made of slate. India-rubber tubing leading from 
 this is conducted, if possible, through the wall into 
 the outer air, and so allowed to run into a drain or 
 waste ground ; the flow of the waste water through 
 this tubing is checked by the aid of spring-clips. 
 Small slabs of variously coloured gutta-percha 
 (Recipe 66) may be fixed to the upper trough, the 
 advantage of the colours being that many dissections 
 are better made on a suitable coloured slab than on 
 any ordinary colour ; if the gutta-percha is found to 
 be too hard, a small piece of tallow may be melted 
 down with it, this makes a slab much superior to wax 
 or cork. In nearly all dissections plenty of water 
 must be used, care being taken that the bottom bath 
 is not allowed to overflow. 
 
 21. Apparatus for cleaning Diatoms (Pig. 24). 
 This is a modification of an older form of apparatus, 
 used for separating diatoms according to their specific 
 gravity. On the shelf is placed a large tin or other 
 vessel containing pure water old Australian meat 
 tins may be used for this purpose. To this vessel is 
 attached a piece of india-rubber tubing. A large 
 confectioner's glass jar of good depth is taken and 
 mounted on a wooden stand, or it may be used as it 
 is; to the top of this fix a cork or wooden cover 
 previously bored, to admit four pieces of glass tubing, 
 three small, one large (see drawing) ; the small size 
 should be about of an inch bore, and the larger 
 
A MANUAL OF 
 
 and longest piece at least f of an inch bore ; fix these 
 into their position in the wooden cover with the 
 cement (Recipe 6), then place on the cover in its 
 right position, and seal and cement it so as to make 
 
 it water and air-tight. Now connect the apparatus 
 with the vessel on the shelf by the aid of the india- 
 rubber tubing; fill the tin with water and let it 
 pass into the glass jar and flow out at the orifice of 
 the three tubes placed in the wooden cover; when 
 an even flow of water is obtained, take three pieces 
 
MICROSCOPIC MOUNTING. 
 
 25 
 
 of glass tubing, each having a capillary orifice, fix 
 these to the projecting ends with small pieces of 
 india-rubber tubing. Now take a quantity of the 
 cleaned diatoms (see Chapter 5), which put into 
 the vessel on the shelf and let them pass gra- 
 dually into the glass jar, the water flowing all the 
 time from the three small tubes ; after a short time 
 has passed, examine a drop of water by evaporat- 
 ing it on a glass slip, and if any diatoms are present 
 they will be found by using the J-inch power of the 
 microscope. If present, collect the water as it flows 
 from each tube into three separate glasses, which 
 must be allowed to stand some time for the diatoms 
 to settle in the form of a deposit. In each glass 
 diatoms will be found of a different size and specific 
 gravity ; by this plan foraminifera and other objects 
 which water does not injure may be separated 
 according to their specific weights. 
 
 22. Finder for Foraminifera, fyc. (Eig. 25) A finder 
 similar to Maltwood's will be found very useful for 
 
 25 
 
 separating any special form of foraminifera or diatom 
 
 It is made as follows : 
 
 from the surrounding mass. 
 
26 A MANUAL OF 
 
 Rule with a writing diamond any number of lines 
 from six and upwards, cross, recross, &c., with other 
 lines, and number the spaces as in the fig. "When it is 
 desired to find any particular diatom place the finder 
 under the microscope, and note the number and square 
 in which it lies, then take it from the stage of the 
 microscope, and with a fine camel's hair brush, moist- 
 ened at the tip, pick it out from the surrounding 
 forms. This is easily done, for if the lines and figures 
 have been neatly and clearly drawn the exact number 
 will be seen with the naked eye. For the method of 
 arranging the figures, &c. 5 see the drawing. 
 
 23. Spirit Lamp (Fig, 26).- 
 This is chiefly used when greater 
 heat and cleanliness are required, 
 for it does not deposit soot like 
 the gas jet, which is important 
 in testing and other purposes. 
 'They may be procured at any 
 FIG. 26. chemist's shop. 
 
 24. Drying Apparatus for Objects (Fig. 27). Sul- 
 phuric acid (So 3 Ho 3 ) has the property of abstracting 
 moisture from surrounding objects ; this is taken ad- 
 vantage of in the following apparatus, which is used 
 for drying specimens. A glass bottle, having a large 
 neck, is fitted with a strong cork or wooden stopper, 
 through this is bored a hole to receive one end of a 
 piece of glass tubing about three-sixteenths of an inch 
 diameter, the other end of the piece of tubing is bent 
 at right angles, and then bent again in a circular 
 manner, so as to form a ring, in which a small evapo- 
 rating dish may be placed (see drawing). This is to 
 contain the object that is to be dried. Sulphuric acid 
 
MICROSCOPIC MOUNTING. 
 
 27 
 
 is now poured into the bottle until it is about a quarter 
 full. The lower surface of the 
 cork or wooden stopper is pro- 
 tected from the corrosive action 
 of the acid the strongest being 
 used by using a cement made of 
 colloid silica, &c. (see Recipe 73). 
 Three or four coatings of this 
 cement must be applied, one after 
 the other, as they dry it is then 
 ready for use. The stopper should 
 fit well but not too tight, as the 
 object might be jerked out of the 
 holder whilst removing it from 
 the bottle. There are many other 
 forms of desiccators but this will 
 be found the cheapest and best. 
 
 25. Apparatus for Making Gases, Distillation, fyc. 
 (Eig. 28). Stoppered retorts will be found the best in 
 the long run for making 
 gases and for use in dis- 
 tillation. Eor though 
 dearer than Florence 
 flasks, yet the increase 
 in price is more than 
 balanced by their in- 
 creased usefulness. The 
 drawing represents the 
 process of distillation. 
 When required for mak- 
 ing gases, india-rubber FlG 28 . 
 tubing is fixed to the retort in place of the receiver, 
 which is on the right hand side of the drawing. 
 
28 A MANUAL OF 
 
 26. Apparatus for Giving Different Degrees of 
 Pressure to Objects whilst Drying (Fig. 29). If the 
 student can make or have made a piece of apparatus 
 like the drawing he will find it much superior, even for 
 ordinary use, where pressure is required, than the 
 rough and ready methods of small wire clips, American 
 paper clips, &c., and at the same time it will he much 
 
 neater and more compact. The drawing represents a 
 case or box with one side open. In the top of this case 
 are drilled holes, through which the pressure rods 
 pass, each rod terminating in a soft velvet cork. On 
 the top of the case, on each side of the pressure rods, 
 are fixed small hooks to receive the elastic bands. 
 Each rod has a hole drilled through it at the top ; the 
 elastic bands are passed through these holes, and then 
 over the hooks on either side (see the drawing). 
 According to the size and strength of these bands, 
 different degrees of pressure are obtained. The most 
 convenient size will be found to be about ten inches 
 long, four inches wide, and five inches high. This 
 size case will take eight or nine slides at once. In the 
 
MICROSCOPIC MOUNTING. 
 
 29 
 
 drawing a slide will be seen in the right position, 
 under one of the pressure rods. 
 
 27. Air Pump (Pig. 30). This form, which is sold 
 hy some of the opticians, will be found the most con- 
 
 venient, but care should be taken to test its air-tight- 
 ness before it is bought, as this form is liable to get 
 out of repair. On referring to the drawing a slide 
 will be seen under the glass cover ready for the 
 exhaustion of the air. The piston is worked until 
 a good vacuum has been obtained. The slide 
 should be allowed to remain thus for ten or fifteen 
 minutes, after which, if all the air bubbles that are 
 contained in the balsam or fluid which is on the glass 
 slide are not gone, the valve may be opened by 
 turning the screw on the left hand side of the drawing, 
 to allow the air to rush in ; then close the valve, and 
 repeat the exhaustion of the air until the air bubbles 
 are entirely gone. The use of this apparatus is only 
 necessary when the object contains much air; in a 
 general way the air bubbles will escape of their own 
 accord. 
 
 28. Lawsons Dissecting Microscope (Pig. 31). This 
 being a binocular microscope will be found much less 
 
30 
 
 A MANUAL OF 
 
 fatiguing than the ordinary compound instrument. A 
 larger range of field is obtained, and much more room 
 for working. Scissors, needles, scalpels, &c., necessary 
 for dissections are sold with it. It forms, when closed, 
 
 FIG. 81. 
 
 a box about six and a half inches long by four inches 
 wide, and it will be found much the best dissecting 
 microscope, especially for beginners. 
 
 29. Apparatus for Drawing, fyc. (Pig. 32). This 
 
 form of apparatus, which can be made exceedingly 
 
MICROSCOPIC MOUNTING. 31 
 
 cheap, will serve for two or three different purposes, 
 i.e., for drawing objects, for taking photographs of 
 objects, and for showing any object to friends without 
 their having the fatigue of looking through the tube of 
 the microscope, which to unaccustomed eyes is rather 
 fatiguing. " A is a deal box placed on a square block 
 of wood of the right thickness ; in this box we cut a 
 circular hole to allow of the tube of the microscope to 
 pass in ; we next fix the object which is to be drawn 
 or photographed upon the stage at B, and throw the 
 full power of the sun's rays directly upon it by means 
 of the reflecting mirror c. If the object is very small 
 a condenser must also be used between the mirror and 
 the stage, so as to condense the rays upon the object. 
 Taking our stand behind the camera, and sliding a 
 ground glass focussing plate into the groove at D, we 
 will cover our head with a black cloth, well known to 
 all lovers of the art, and bring a clear image of the 
 object upon the surface of the plate by means of the 
 screw at E. Our arrangements are then complete : 
 the ground glass represents with perfect fidelity the 
 relation of the retina to the picture under ordinary 
 circumstances, and we have but to make it highly 
 sensitive to the decomposing influence of light to 
 produce the desired result. Replacing this artificial 
 retina, therefore, with collodionised glass, and allow- 
 ing it to be exposed to the sun's rays for some few 
 seconds, we have only to remove and develop, in 
 the ordinary way, the picture which will have been 
 formed. This is an outline of the process, but in 
 practice scarcely any branch of photographic manipu- 
 lation requires greater skill, delicacy, and patience 
 than this. One great source of failure which besets the 
 
32 A MANUAL OF 
 
 amateur is the singular though well-known fact that 
 the visual and chemical foci of a lens do not absolutely 
 coincide ; or in other words, the focussing which 
 would give a completely denned picture to the eye 
 upon the ground glass slide D, will produce a blurred 
 and hazy image on the collodionised plate. One or 
 two trials will soon establish the correct focal length : 
 the negative may then be taken, and any number of 
 positives taken from it." If it is desired to draw the 
 object, instead of photographing it, a piece of thin 
 tracing paper must be fixed to the ground glass slide 
 by the aid of gum at the corners of the paper. 
 The object is drawn on it, and a retracing from this 
 on to white paper must then be executed in the usual 
 manner. The same arrangement will do for showing 
 objects to a number of people at once, only in this 
 case a strong light must be used Piddian's lamp is 
 about the best. The light must be enclosed and 
 carried through a tube, or the stage of the microscope 
 and the lamp may be enclosed in another box. 
 
 30. Neutral Tint or Thin Glass 
 Reflector (Pig. 33). This is the 
 cheapest form of apparatus for 
 drawing ; it is used with the 
 microscope in a horizontal position 
 in the same manner as the camera 
 lucida (Pig. 34). 
 
 31. Camera Lucida as used for 
 Drawing (Pig. 34). To draw an object the camera 
 lucida is fitted to the eye-piece, the cap having been 
 taken off. The microscope is then placed in a hori- 
 zontal position and the body of the instrument must 
 be raised until the prism of the camera is ten inches 
 
MICROSCOPIC MOUNTING. 
 
 33 
 
 from the paper, which Inust be placed upon a flat 
 surface like a table (see the drawing). In using the 
 camera, one eye only must be used; half of the pupil of 
 this eye must be directed over the edge of the prism, 
 when the object will appear upon the paper, and may 
 
 FIG. 34. 
 
 be drawn with a pencil. If any number of drawings 
 are to be made, it is as well to use the drawing paper 
 pads sold by Messrs. Winsor and Newton. 
 
 32. Pipettes (Eig. 35). These are used for collecting 
 small quantities of diatoms, &c., after they are depo- 
 
 D 
 
A MANUAL OF 
 
 sited at the bottom of any glass or other vessel. It is 
 as well to have a small piece of india-rubber sheeting 
 over the top. In use, this will be found to assist in 
 preventing the speed at which any deposit will run 
 
 FIG. 35. 
 
 from it, the finger being placed with different degrees 
 of pressure. 
 
 33. Glass Cells (Pig. 36). These cells are made by 
 drilling holes in pieces of glass of various sizes and 
 shapes. If it is desired to have shallow cells, thin glass 
 
 FIG. 36. 
 
 must be used instead of the ordinary glass ; if this is 
 used it may be cut with the writing diamond instead 
 of drilling. 
 
 34. Compressorium (Pig. 37). It is. often a great 
 help to microscopic research to be able to apply com- 
 pression to any object which may present itself on a 
 slide while still remaining in the field of view. Most 
 workers prefer to press down the cover on a slide, 
 with the point of a porcupine's quill, &c. In many 
 cases the object is too much crushed, or the cover 
 broken, or it slips out of the field of view, and it is 
 often nearly impossible to find it again. The com- 
 pressorium here represented will, I think, be found to 
 possess many advantages, and its use will get rid of 
 
MICROSCOPIC -MOUNTING. 
 
 35 
 
 all the difficulties indicated above. It consists of two 
 parts the stage and the compressor. The stage, 
 A, B, c, D, is a flat brass plate, with a circular 
 opening bevelled beneath, so as to allow any kind of 
 condenser to be applied below, and with two small 
 short pins projecting below at A and B (not seen in 
 the diagram), and which fit tightly into the small 
 holes usually made in the upper part of the moveable 
 stage of all microscopes, so as to keep the plate firmly 
 fixed to the stage of the microscope. The compressor 
 (K, I, H, M, N) is turned off the stage, and remains 
 in that position when not in use. It consists of a 
 
 FIG. 37. 
 
 stout arch of brass, terminating in two feet ; one, H, 
 on which it pivots, and which should be made stout 
 and strong ; the other foot, K I, ends in a shoe, with 
 a spring catch, i, and which, when the compressor is 
 
 D 2 
 
36 A MANUAL OF 
 
 turned round on the pillar, H, fits into the notch, c, 
 and can be released by the finger acting on the pin, 
 K; the compressing plate, M, N, is acted upon by the 
 milled head, p, and can be lowered and raised to any 
 extent required, by a micrometer screw to which it is 
 attached. With the compressorium fixed on the stage 
 of the microscope (the compressor turned off as in the 
 dotted lines), every kind of microscopic work can go 
 on just as well as if the compressorium were off the 
 stage ; in fact, it is not at all in the way. However, 
 when anything requiring compression turns up in a 
 microscopic research, the compressor part can be 
 pivoted round the pillar, H, so as to occupy the 
 position indicated in the continuous lines, and that 
 without disturbing the slide, cover, or object glass 
 (although a little retraction of the object glass may 
 be made in order to see what you are about) ; and 
 then, by turning the milled head, p, the plate, M, N, 
 is lowered gradually parallel to the stage, and the 
 object is proportionally compressed ; the inner part of 
 plate, H N, is bevelled off to enable the observer to 
 follow the object to a considerable degree should it be 
 inclined to slip from under view. When the com- 
 pression is ended, the milled head, p, is worked back 
 to raise the compressing plate clear of the slide, and 
 the compressor can be again turned aside on releasing 
 the catch with the finger at K." This instrument is 
 particularly useful in the examination of the Entromo- 
 straca Rhizopoda and Rotatoria in fact, in nearly 
 every department of microscopic work ; it will also 
 save a vast amount of trouble. The instrument is 
 sold by Mr. Thomas Ross, London, 
 
 35. Machine for Cutting Rock Sections, fyc. (Pig. 38 
 
MICROSCOPIC MOUNTING. 
 
 37 
 
 and Pig. 38A.) "As will be seen from Pig. 38 and the 
 diagram on p. 38, this machine consists of a wooden 
 framework, aa, supporting a crank-axle and driving- 
 wheel, two feet diameter ; the top part of the frame 
 consists of two cross-pieces, a, fixed about an inch 
 apart as in the bed of an ordinary turning lathe ; 
 into the slot between them is placed a casting, B, 
 carrying the bracket for the angle-pulleys, c; this 
 casting is bored to receive the spindle, D, which, by 
 
 FIG. 38. 
 
 means of the treadle, is made to revolve at the rate 
 
38 
 
 A MANUAL Ol 1 
 
 of 400 or 500 revolutions per minute. It is also 
 bored to receive another spindle, E, to the top of 
 which is fixed a metal plate, r, for carrying the small 
 cup, n, to which the specimen is attached by means 
 of prepared wax. This means of mechanically apply- 
 ing the work to the slicer is far preferable to holding 
 it in the hand in the ordinary way ; the requisite 
 pressure against the cutting disc is regulated by the 
 weight, G, and the thickness of the slice by the 
 thumb screw, K, on which the spindle rests. By this 
 means it is possible to cut tolerably thin and parallel 
 slices the thinness, of course, varying according to 
 the strength of the rock which is being operated upon, 
 The slitting disc is made of soft iron, eight inches 
 
 FIG. 38A. 
 
 diameter, and about - 5 Vth of an inch in thickness, and 
 it is fixed on the spindle, D, between two brass plates 
 
MICROSCOPIC MOUNTING. 39 
 
 four inches diameter in the usual way. The operation 
 of charging the edge of the disc with diamond 
 powder requires some little care. Having reduced 
 the diamond to the requisite degree of fineness in a 
 hardened steel mortar (so fine that no sparkling is 
 perceptible on exposure to light), a few grains are 
 placed in a watch glass, made into a paste with a 
 drop of sweet oil, and applied to the edge of the disc 
 with a quill ; while the disc is heing slowly revolved 
 by hand, it must be gently pressed in with a small 
 roller of glass or hard steel, until the particles of 
 diamond powder are securely bedded in the edge of 
 the metal, care being taken to avoid getting any of it 
 on the sides of the slicer. In cutting it is necessary 
 to steady the work with the hand, and not to trust for 
 pressure entirely to the suspended weight. The 
 work must be constantly lubricated with oil; spirits 
 of turpentine will, however, answer the purpose. 
 When it is possible to obtain a sufficiently thin piece 
 of the specimen by a dexterous chip with the hammer, 
 or other means, the operation of slitting may of course 
 be dispensed with. 
 
 Having prepared suitable slices of about yg-th or ^th 
 of an inch in thickness, it is necessary to reduce them 
 still further by grinding with fine emery and water on 
 a lead "lap," which is made to revolve on the spindle 
 D. The lap is eight inches diameter, and about f ths of 
 an inch thick in the centre, cast with rounded edges 
 and slightly convex sides ; this form facilitates the 
 grinding of a uniform thinness, there being always a 
 tendency on a fiat surface (which soon wears hollow) 
 for the edges of the section to grind away before it is 
 sufficiently thin. One side of the section can easily 
 
40 A MANUAL OF 
 
 be ground and finished by holding in the hand, and 
 this being clone, it must be cemented with hard 
 Canada balsam to a small square of plate glass : in 
 order to grind the other side, it is as well to protect the 
 corners of the glass with small pieces of zinc whilst 
 the operation of grinding is going on. When the 
 sections are to be mounted in balsam it is not neces- 
 sary to polish them ; the only finish required is to rub 
 them on an Arkansas stone until the scratches, &c., 
 are removed." (See also Rock Sections, Chapter 5.) 
 
 36. Trough used for observing the circulation of blood 
 in Tadpoles, Sfc. (Fig. 39) . "The tadpole trough shown 
 
 FIG. 39. 
 
 in the engraving will be found very useful. A A, is a 
 glass stage raised a quarter of an inch above the plate, 
 and having beneath it an aperture in the plate. B, is 
 trough entirely covered in, the cover of which, c, is 
 
MICROSCOPIC MOUNTING. 41 
 
 here removed to show the interior. The trough is 
 kept constantly full of water hy the supply-pipe, D ; 
 this water may be conveyed from a small reservoir of 
 water kept 011 a shelf, like in Eig. 24, paragraph 21. E, 
 is the waste-pipe; F, is a little cage made of pieces 
 of pin- wire, and of such a size as to hold easily the head 
 of a full sized tadpole. The apparatus being placed 
 on the stage of a microscope inclined at an angle of 
 45, a tadpole is deposited from a small teaspoon on 
 the lower part of the glass stage (about the point G.) 
 The head immediately falls into the cage, r; the 
 tadpole turns on its side, the tail lying across the glass 
 stage, as shewn in the dotted outline. The silk cord, 
 H, is used to hold the animal in its place. A glass 
 cover is now laid on the tail. The tadpole should not 
 be left in more than three hours at a time. The 
 circulation is apt to flag during the first ten minutes; 
 it then revives. By this plan the circulation of the 
 blood is well shewn, also the changes in the inflamed 
 parts, &c." See also "Circulation," Chapter 5. 
 
 37. Other small pieces of apparatus will be found ex- 
 tremely useful in washing tissues, i. e., glass syringes, 
 with their points drawn to different degrees of fine- 
 ness and also bent to different curvatures. (SeeEig40.) 
 
 FIG. 40. 
 
 38. A capital instrument for holding slides whilst 
 heating over lamp, &c., has lately been devised by 
 Mr. James Smith. Its description, according to Dr. 
 Carpenter, is thus : " It consists of a plate of brass 
 
42 A MANUAL OF 
 
 turned up at its edges, of the proper size (i.e., 3x1 
 inch) to allow the ordinary glass slide to lie loosely on 
 the hed thus formed. This plate has a large perfora- 
 tion in its centre, in order to allow heat to he directly 
 applied to the slide from heneath, and it is attached hy 
 a stout wire to a handle. (See Pig. 41). Close to 
 
 FIG. 41. 
 
 this handle there is attached hy a joint, a second wire, 
 which lies nearly parallel to the first, hut makes a 
 downward turn just ahove the centre of the slide 
 plate, and is terminated hy an ivory knoh (cork would 
 do) ; this wire is pressed upwards hy a spring heneath 
 it, whilst, on the other hand, it is made to approxi- 
 mate the other hy a milled-head turning on a screw, 
 so as to "bring its ivory knoh to hear with greater or 
 less force on the covering glass." The use of this 
 instrument will he self-evident from this description, 
 and from the drawing which accompanies it. 
 
 39. Another useful kind of apparatus for measuring 
 the thickness of thin glass covers has heen invented 
 hy Mr. Ross; "It consists of a small horizontal 
 tahle of hrass it might he zinc mounted upon a 
 stand, and having at one end an arc graduated into 
 20 divisions, each of which represents ToVo^ 1 f & n 
 inch, so that the entire arc measures ^th of an inch. 
 At the other end is a pivot, on which moves a long 
 and delicate lever of steel, whose extremity points to 
 the graduated arc, whilst it has very near its pivot a 
 sort of projecting tooth, which hears at * against a 
 
MICROSCOPIC MOUNTING. 
 
 vertical plate of steel that is screwed to the horizontal 
 table. The piece of thin glass to be measured, being 
 inserted between the vertical plate and the projecting 
 tooth of the lever, its thickness in thousandths of an 
 inch is given by the number on the graduated arc to 
 which the extremity of the lever needle points. Thus, 
 if the number be 8, the thickness of the glass is '008 
 or Tarth of an inch, thus : 
 
 Inch. 
 
 1 
 8^000 
 
 Inch. 
 
 1 
 
 20.000 
 50 
 
 Inch. 
 JL 
 50 
 
 8.000)1.000.000/7^ Inch. 
 - son n V 125 
 
 800.0 
 .200.00 
 
 160.00 
 -40 000 
 40000 
 
 After measuring a quantity of thin glass, it will be 
 found most convenient to keep them separate ac- 
 cording to their thickness for when examining any 
 special object or series of objects it will save much 
 time and trouble especially when high powers are 
 
 FIG. 42. 
 
 used, as the focus need not be changed. It is not desira- 
 ble to use glass covers of greater thickness than .007 
 of an inch, with object glasses of 75, and for those of 
 120 and upwards, use covers .004 inch. This piece of 
 apparatus may be easily made, thus : Cut a piece of 
 
44 A MANUAL OF 
 
 sheet zinc about 3 X 1^ inch, then with needle pointed 
 compasses, make the segment of the arc (see Eig. 42), 
 then roughly measure the thickness of a piece of thin 
 glass as nearly as possible s^-th of an inch in thick- 
 ness now place it on end and take the exact thick- 
 ness by means of the eyepiece micrometer, using a 
 low power ; then make a zero mark on the left-hand 
 side of the arc, bend a long slender needle at an 
 angle as shown in the drawing, pass a small screw 
 through the eye of the needle so that it may work on 
 it as a pivot, to the eye of the needle solder a small 
 projecting lever or tooth; now cement or solder a 
 small piece of zinc or copper, having an exact 
 straight edge, immediately below the tooth and touch- 
 ing it (see Pig. 42) ; now cut out the zinc as shown 
 in the drawing, then bend another needle in the form 
 of a spring, and fix it by means of a screw pivot im- 
 mediately above the registering needle, measure a 
 piece of thin glass about -^>-th of an inch, as before- 
 mentioned, place the point of the needle at zero, 
 letting the tooth touch the bottom supporting plate, 
 pass the piece of thin glass under the tooth, and 
 notice where the point of the needle rests; mark this ; 
 then between the point zero and this mark, space out 
 20 equal spaces, and with an etching needle, number 
 each division, which, if the thin glass is ^-th of an 
 inch, will of course be TFo^th f an inch. 
 
 40. Another useful piece of apparatus, which the 
 practical and scientific microscopist can scarcely do 
 without, is a good dialyser (see Eig. 43). Make it as 
 follows : Take a hoop of either wood or gutta-percha, 
 cover this on one side with a disc of parchment paper, 
 which should measure 3 or 4 inches more in diameter 
 
MICROSCOPIC MOUNTING. 
 
 than the space to be covered. " It is then moistened 
 and stretched over the hoop, and fastened by a string 
 or an elastic band, but it should not be secured too 
 firmly. The parchment paper must not be porous ; 
 its soundness may be tested by sponging the upper 
 side with water, and observing whether wet spots 
 show on the other side. Defects may be remedied by 
 applying liquid albumen, and coagulating this by 
 heat. When the dialyser has thus been got ready, the 
 mass to be examined is poured into it. The depth of 
 fluid in the dialyser should not be more than half an 
 inch, and the membrane should dip a little way below 
 the surface of the water in the outer vessel, which 
 should amount to at least four times the quantity of 
 the fluid to be dialysed. The hoop is simply floated 
 on the water. If the dialyser is brought successively 
 in contact with fresh 
 supplies of water, the 
 whole of the crystalloids 
 may be finally separated 
 from the colloids . This 
 is often of great service 
 in chemico-legal inves- 
 tigations for the extrac- 
 tions of poisonous crys- 
 talloids from parts of a 
 dead body, food, vomit, 
 &c., and with " ready FIG. 43. 
 
 wit " will be found of considerable advantage to all 
 scientific microscopists ; thus, for instance, taking 
 soda or potash from any tissue that has been treated 
 with them without disturbing the position of the 
 same. 
 
46 
 
 A MANUAL OF 
 
 41. My attention has lately been called to a very 
 useful little piece of apparatus, invented by my friend, 
 Mr. E. P. Grensted, of University College, Oxford. 
 Its object is to partially take the place of the more 
 expensive apparatus, i.e., the parabolic reflector. Its 
 construction is very simple, consisting only of a glass 
 slip 3x1 inch, with a small slip of looking-glass 
 cemented to it at right angles. (See Pig. 44). In 
 
 D 
 
 using, the slip is placed under the slide that is being 
 examined, the mirror being on the under side and 
 
MICROSCOPIC MOUNTING. 47 
 
 partially facing the mirror of the microscope, light 
 is then reflected from the mirror of the microscope on 
 to the mirror of the slide, which again reflects it at 
 an angle on to the object, the rays which are not 
 intercepted by the object passing behind the focus 
 of the object glass, the field of view is therefore left 
 dark, as in the case of the parabolic reflector. 
 
 The illustrations will, I believe, sufficiently explain 
 the construction of the apparatus, and also its use. 
 
 EXPLANATION OE PIGS. 44-45. 
 
 A. Object glass of microscope. 
 
 B. Stage. 
 
 C. C. Mirror. 
 
 D. D. D. Slide carrying mounted object. 
 
 E. E. The apparatus for the dark back ground. 
 
 F. E. E. Course of the rays of light. 
 
 Gr. Perspective view of apparatus, i.e. \ ?' pV 1 ^ \*J. 
 
 N.B. The piece of looking-glass is f X 1 inch, 
 to be fixed as per drawing to the usual glass slip, 
 3x1 inch, at the distance of 1 inch from the end. 
 It can be fixed by means of sealing-wax if both glasses 
 are previously made hot. 
 
 This apparatus cannot well be used with objectives 
 higher than -J an inch. 
 
 42. Dr. Golding Bird has lately invented a new 
 differential warm stage. The instrument is made as 
 follows : In the centre of a disc of copper, about the 
 size and thickness of a halfpenny, a square or cir- 
 cular hole about f ths of an inch across is cut, while 
 let into it on one edge (as shown in the wood-cut), and 
 firmly soldered, is an iron wire y^th of an inch in 
 
A MANUAL OF 
 
 diameter, and 5 inches long. To the same edge is 
 soldered also a tongue of copper, in the position shown, 
 an inch long, and a of an inch in breadth. A 
 piece of ordinary copper bell-wire is now wound 
 round both the copper tongue and iron wire for four 
 turns, commencing close to the disc, after which the 
 wire is carried on up the iron wire only, covering it 
 for 3J inches, reckoning from its attachment to the 
 
 disc ; both the four 
 large turns and the 
 smaller subsequent 
 coil should be 
 closely wound, a 
 little separation, of 
 about the thickness 
 of one coil, being 
 allowed between 
 the last of the large 
 and the first of the 
 small turns. This 
 prevents the heat 
 being too rapidly 
 conveyed to the 
 stage. The disc is 
 now fastened with 
 sealing-wax to a 
 glass slide, the wire 
 projecting beyond, while in the places where the labels 
 are usually placed should be gummed slips of card- 
 board on both surfaces, so as to prevent the immediate 
 contact of any part of the instrument with the stage 
 of the microscope. 
 
 It does not matter how the iron wire is bent ; that 
 
 FIG. 46. 
 
MICROSCOPIC MOUNTING. 49 
 
 here shown is a very convenient form. A small ther- 
 mometer may now be fixed between the large coils of 
 wire and the circular opening in the copper disc. The 
 thermometer is made thus : Take a vaccine capillary 
 tube about 3 inches long, seal one end of the tube by 
 the action of spirit lamp, then allow tinted alcohol 
 (tinted with an aniline dye) to flow up the open end 
 of the tube until about -^ an inch of the entire length 
 has been filled ; hold the tube so that the alcohol may 
 How to the other, and sealed side, then seal the open 
 end by the spirit flame. To roughly graduate this 
 thermometer, place both it and a good centigrade 
 thermometer in a horizontal position on a large sand- 
 bath, which heat over a Bunssn burner iintil 40 C. is 
 registered note this by a small dot of black varnish 
 on the capillary tube ; now run up the heat until it 
 reaches 100 C. also note this by making another 
 mark on the tube ; equally divide the space between 
 the two marks into 12 divisions each of these will 
 roughly show 5 degrees centigrade; now fix this 
 roughly made thermometer on the top of the copper 
 disc, the end containing the tinted alcohol resting 
 against the iron wire. The object to be observed 
 under the action of heat is then placed on a circle of 
 thin glass, water, &c.. added, a smaller cover placed 
 over this, and small pieces of, or melted, Cacao butter 
 allowed to flow round the edge so as to prevent the 
 evaporation of the fluid under observation. 
 
 Before using, the instrument should be made slightly 
 warm, then placed on the stage of the microscope, the 
 object fixed for observation as before mentioned. The 
 flame of the spirit lamp is then made to play upon the 
 end of the iron wire until the required degree of heat 
 
 E 
 
50 
 
 A MANUAL OF 
 
 is reached, and then with a little care, this tempera- 
 ture may be maintained for an indefinite period. The 
 use of this instrument in the examination of starches, 
 blood, &c., &c., is manifest. 
 
 43. Glasses, 8fc., for Aquaria (Pig. 47) . No micro- 
 scopist should be without at least one large con- 
 fectioner's jar, or a propagating glass (see drawing) 
 filled with pond water, in which to keep water- insects, 
 desmids, diatoms, &c. The aquarium should not be 
 
 FIG. 47. 
 
 larger than two feet in diameter ; that is, if it is used 
 for keeping water-insects. When at the seaside, if it 
 is desired to keep minute marine objects, a piece of 
 seaweed growing on a limpet- shell or piece of rock 
 should be placed in the sea- water for at least two days 
 before any zoophytes, &c., are placed there. Rough 
 stands for the bell glasses can always be made out of 
 a block of wood or an old white jar, &c. (see the 
 drawings). It is very interesting to grow species of 
 desmids, &c., in separate jars. 
 
MICROSCOPIC MOUNTING. 
 
 51 
 
 44. Collecting Bottle (Pig. 48). These bottles are 
 used for collecting small beetles and other insects. A 
 small wide-mouthed bottle being chosen, a cork is bored 
 exactly in the centre with a cork-borer or rat-tail file ; 
 into this hole is cemented a piece of quill of about the 
 length of a (Fig. 48). Some small pieces of bruised 
 
 FIG. 48. 
 
 laurel leaves are taken and kept in their place by the 
 aid of a circular piece of fine muslin, see b. c shows 
 the sectional view of the cork with the muslin pad. 
 The muslin can be fastened to the cork with glue or the 
 small pins used by drapers. A camel's hair brush in 
 a short cedar handle is now fixed to the cork with a 
 piece of fine string (see drawing) ; this brush must be 
 kept constantly damp. Glycerine will be found 
 useful for this purpose. The cork may now be placed 
 in the bottle, rather tightly, for it does not require to 
 
 E 2 
 
52 A MANUAL OF 
 
 be taken out until sufficient insects have been collected. 
 The drawing illustrates an insect falling into the 
 bottle after being caught with the aid of the brush. 
 A small piece of silk or muslin must be kept in the 
 bottle, for the beetles, &c., to cling to ; this prevents 
 their being crushed. 
 
 45. When exhibiting any series of objects either to 
 fellow- students or friends, it will be found a good plan 
 to have a moveable board so fitted as to carry a 
 microscope, one lamp, and sufficient space left for all 
 other necessary apparatus. This board should he 
 triangular, one side of it covered with baize, and the 
 other with American leather; the baize side to be 
 used on a smooth surface like a polished table, and 
 the leather side on a rough surface like a table 
 already covered with a table cloth. This plan will be 
 found a great advantage where many objects are 
 shown, as it is not necessary to move either the lamp or 
 the microscope when once fixed in right position, the 
 board only being moved as required. 
 
 46. Propagating or bell glasses may be obtained of 
 Messrs. Claude t and Houghton, High Holborn. 
 
 47. Test tubes and chemicals I always get from 
 Mottershead and Co., Manchester, the price of the 
 tubes being only about 3s. per hundred. 
 
 48. Scalpels, razors, Valentine's knife, scissors, &c., 
 may be obtained of any optician or instrument maker. 
 
 49. Crucibles. I find the best place to get these is 
 from the Plumbago Crucible Company, Battersea, 
 London. 
 
 50. Re-agents (see Chapter 7). 
 
 51. The large tins in which the Australian meat is 
 sold will be found very useful for many purposes. 
 
MICROSCOPIC MOUNTING. 53 
 
 52. The microscopist, especially if he is fond of 
 chemistry as well, should not be without a small 
 dialysing drum, which may be made as follows : 
 Over one side of a lamp- glass chimney, tie or fix with 
 cement a piece of sheet india-rubber or bladder, 
 great care being taken that it is tightly fixed. It is 
 now ready for use, for the method of which see 
 Recipe 9, and paragraph 40, it will be found very useful 
 in separating salts, especially from glycerine, &c. 
 
 53. When a moderate heat only is required for 
 slides whilst in process of mounting, a good plan is 
 to use an ordinary basin filled with boiling water, 
 over which invert a plate, but the best plan is to get 
 a tinman to make a square tin box about seven 
 inches square and four inches high, a small hole 
 only being left open in one corner, through which 
 the boiling water must be poured in; a cork being 
 used to stop the hole. X.B. It is better to use a water 
 oven if possible. 
 
 54. Lffwp. An ordinary paraffin lamp will do for 
 most purposes of illuini nation, but if a better is 
 required I prefer Eiddian's lamp, though many 
 others are sold by Mr. How and other opticians, 
 which are nearly as good. 
 
 55. The student must not forget to obtain or 
 make a small soldering-rod, like those used by gas- 
 fitters, only much smaller. 
 
 56. A good blowpipe will also be found useful, 
 especially in fusing borax, beads, &c., for micro- 
 scopical examination. 
 
 57. Yery good and useful spring clips can be 
 obtained of Mr. Baker, 244, High Holborii. 
 
54 A MANUAL OF 
 
 SECTION II. 
 
 THE DRY METHOD OF PREPARATION OF VARIOUS 
 MICROSCOPICAL STRUCTURES. 
 
 58. The dry method of mounting may be con- 
 sidered the easiest of all the plans that are used for 
 preparing microscopic inorganic and organic sub- 
 stances. It may be considered as divided into two 
 large divisions : viz., the dry transparent, and the 
 dry opaque modes of preparation. 
 
 59. But before we begin, it is as well to inform the 
 student that if possible a separate room, however 
 small, should be at his disposal ; and it is preferable to 
 have the floor of this room or workshop covered with 
 floorcloth, as the woollen fibres from carpets and drug- 
 gets generally float in the air of the room, and however 
 careful the manipulator may be, fine fibres will often 
 rest on a careful dissection or preparation and not be 
 noticed until the thin glass is applied. When, if 
 delicate, to remount the object would most likely 
 injure, if not spoil it. Therefore, it is advisable to 
 examine the dust of the room with his microscope, and, 
 if fibres are found, to trace them to their source and 
 remove it. If only inorganic dust remains, the room 
 may be considered ready for future work; and we wish 
 our readers success. 
 
 60. Dry Transparent Method. For this mode of 
 mounting the student may have ready to hand on his 
 mounting-table or bench the following articles : 
 
MICROSCOPIC MOUNTING. 55 
 
 Two dozen glass slips : viz., one dozen rough edge 
 crown slips, and one dozen patent plate ground edge 
 slips. Six of the ground edge and six of the 
 rough edge are to be used for the transparent 
 method of mounting, and the same number for the 
 opaque. 
 
 Eighteen thin glass circles, this number to allow 
 for breakage ; the sizes are to be two of the f inch, 
 eight of -J- inch, five of f inch, and three of the 
 inch, 
 
 Eighteen thin glass squares, the sizes to be three 
 1-J by f inch, five of the -| inch, six of the f inch, 
 and four of the % inch. 
 
 These sizes will be found the best for the mounting 
 of the objects that I shall describe 
 
 Apparatus with wire clips ; the section cutter ; the 
 holding screw; both of the drying apparatuses; the bell 
 glasses and the broken wine-glasses ; two of the test 
 tubes and holder; forceps, one pair; one scalpel; both 
 pairs of scissors ; the spirit-lamp ; a few of the watch- 
 glasses ; a small camel's hair brush; Matthews' turn- 
 table ; the small soldering-rod ; the writing diamond ; 
 file, saw, copper- wire, &c. ; caoutchouc cement ; gold 
 size ; Berlin black ; and the gum-bottle and cases 
 necessary for covering twelve slides, as the other 
 twelve will be on the ground edge slips. 
 
 We will take the following twenty-four objects, 
 twelve transparent and twelve opaque, and I have 
 chosen them on account of their being easily obtained; 
 and if the reader will follow the process of mounting 
 he will gain a fair amount of experience in the dry 
 process, they being to a certain degree typical slides 
 taken from Chapter 5 : 
 
56 A MANUAL OF 
 
 1. Wing of cabbage butterfly, properly called the 
 small garden white (Pier is rapce), R.E.* 
 
 2. Eye of house-fly (Musca dome s tic a] , H.E. 
 
 3. Scale of Roach (Leuciscus rutilus), E,.E. 
 4 Diatoms (Diatoma vulgar e), G.E. 
 
 5. Section of human, or other bone, H.E. 
 
 6. Pollen of bird's foot trefoil (Lotus corniculdtus) , 
 G.E. ; pollen of fumitory (Fumaria officindlis) ; or 
 pollen of hyacinth (Hyaci/nthus orientalis). 
 
 7. Spores of an equi$etum(Eq?Msettim telmateia)^.~E 
 
 8. Tran verse section of rush (Juncus communis), G.E. 
 
 9. Transverse section of oak (Quercus robur), E.E. ; 
 dog rose (Rosa ccmina) ; or any wood which shows 
 exogenous structure. 
 
 10. Cuticle of ivy (Seder a helix], with the stellate 
 hairs attached to it, G.E. 
 
 11. Monopetalous corolla of pimpernel (Anagdllis 
 arvensis), E/.E. 
 
 12. Sulphate of Lime (SOoCao"), G.E. 
 
 The other twelve objects are named and described 
 in the next division; under the head of dry opaque 
 mounting. 
 
 "We will take the objects in the same order as they 
 are numbered. 
 
 Slide 1. Wing of cabbage butterfly (Pieris rap<e). 
 It is easy to catch one of these insects, as they are 
 very common. After it is caught, kill it by piercing 
 the thorax, and if necessary apply one drop nitric 
 acid with the needle ; one wing must then be cut 
 off and placed under one of the wine-glasses to pro- 
 tect it from dust, and also the chance of being 
 blown away. Then take one of the rough edge 
 
 * E.E. signifies rough edge slip; G.E. signifies ground edge slip. 
 
MICROSCOPIC MOUNTING. 57 
 
 slips and thoroughly clean and polish it ; and if there 
 is any difficulty in removing the dirt, use a strong 
 solution of caustic soda or potass, but if either of 
 these are used the glass must he well washed in 
 cold water to remove all traces of them. Then 
 polish with an old silk handkerchief or wash-leather, 
 I prefer the silk ; then take one of the pieces of thin 
 glass, 1^ inch hy f inch, clean with the silk hand- 
 kerchief, with less pressure of the fingers, as the 
 glass is very brittle ; if any great difficulty "is found 
 in cleaning this glass without breaking it, use 
 rubbers made thus : take two pill boxes, and cement 
 wash-leather to the bottom of each, fill the boxes 
 with plaster of Paris to give them weight, then put 
 the lids on, and give them a coating of sealing-wax 
 varnish to make them look neat ; when dry and 
 ready for use place the piece of thin glass between the 
 wash-leather sides, and gently rub them together. 
 By this plan it will be thoroughly cleaned without 
 the risk of breakage. When perfectly clean, draw 
 a thin layer of gold size all round the piece of thin 
 glass, 011 which place four narrow slips of paper. Let 
 these dry ; then place another thin layer of gold 
 size over the paper slips, and whilst this is drying, 
 measure the width of the wing of the butterfly; if 
 too wide cut a small piece from each side, so as to 
 make it about ^th of an inch less in width than the 
 piece of thin glass ; then place it in the centre of the 
 glass slip, but previously rub a few of the scales off, 
 so as to make it semi-transparent. This is necessary 
 to show the arrangement of the scales. The exact 
 centre of glass slips is best taken as follows : Draw 
 lines on a piece of thick cardboard, the exact size of a 
 
58 A MANUAL OF 
 
 glass slip, viz., 3 inches by 1 inch; then from each 
 corner rule a line to the opposite corner, so that 
 both lines may cross in the centre this will give an 
 exact centre for all slips. Always centre a quantity 
 of slips at one time, by placing them over this guide, 
 and with a pen depositing one small drop of ink in 
 the exact centre. 
 
 Now we will take the thin glass and place it over 
 the wing, and taking the soldering-rod, which has 
 been previously made hot, either by a fire, spirit- 
 lamp, or gas, gently touch the edge of the thin glass 
 all round, which will cause the gold size to flow; 
 and if well done, make an hermetically sealed cell. 
 When thoroughly dry, which will be in about two 
 or three days, another slight coat of varnish must 
 be put all round the edge of the cover; but this 
 time it is better to use the sealing-wax varnish. 
 The slide must then be put aside for a day before 
 it is covered with the ornamental paper covers if 
 these are used if not, another thin layer of sealing- 
 wax varnish, or what is much better, Berlin black, 
 may be applied, and the name and date written 
 on a small paper label, or the glass itself 
 may be written upon with the writing diamond. 
 It is always well to put the date of the day 
 when mounted, as this is often a great guide in 
 fluid and other preparations as to the properties and 
 quality of the various cements, fluids, &c., used in 
 their preservation. 
 
 Slide 2. Eye of House-fly (Musca domestica). 
 Catch and kill one of these insects. Cut off the head 
 as in A, Pig. 69. Plate 5 ; then separate one eye from 
 the head, as seen in A, Pig. 70 ; soak it in a solution of 
 
MICROSCOPIC MOUNTING. 59 
 
 potass until it becomes soft and all the extraneous 
 matter is separated from it, which process assist by 
 gently brushing it with a soft hog's-hair brush until 
 it is clean ; let it lay in the potass at least two hours 
 before using the brush; wash well in warm water 
 and then in cold; slightly dry by placing it on a 
 piece of blotting-paper and remove to a small piece 
 of cardboard, which place in the object holder of the 
 drying apparatus (see Eig. 27) until dry, which, as 
 the object is small and of thin texture, will soon 
 occur. Remove it to a glass slip which has been duly 
 centred ; but care should be taken that it is not placed 
 on the drop of ink, but immediately opposite to it on 
 the other and clean side; trim the edges with a 
 scalpel, then proceed in the same manner as 
 described for mounting the wing of a butterfly ; 
 press the thin glass slightly after applying the 
 soldering-rod, so as to make perfect adhesion 
 between the glasses and the gold size, and it is as 
 well to see that all cements are perfectly dry before 
 covering with paper (that is if covers are used 
 which I do not recommend if the objects are to be 
 mounted for study, for though they make the slides 
 look better, they greatly interfere with any alterations 
 and observations which the student may desire to 
 make). But as some persons may prefer to cover their 
 objects, I give a slight sketch of the way to proceed. 
 At Plate 1, Fig. 49, is a representation of a slide in 
 the same stage of progress as the eye of the house fly, 
 a description of the process of mounting which we 
 have just given ; it also roughly represents the same 
 object. A piece of paper 3^ inches by 1^ inch is cut 
 from a sheet coloured red on one side and gummed on 
 
60 A MANUAL OF 
 
 the other ; this paper is sold at most stationers (or the 
 pieces already cut in packets of 100 may be bought at 
 most opticians) ; a hole is then punched in the exact 
 centre (see Pig. 50) ; a wet brush is then passed over 
 the gummed surface, and the slide laid upon it, so that 
 the hole may come exactly in the centre of the thin 
 glass, only on the opposite side; then, with a sharp 
 pair of scissors, cut the* paper as represented in the 
 clotted line, Pig. 50 ; the gummed surface must then 
 be moistened, and the edges folded over the glass slip 
 very tightly, as shown in Pig. 51 ; after all the four 
 edges are brought over, the ornamental cover must 
 have its gummed surface moistened with the brush, and 
 laid so that its hole, which has been previously punched 
 out, shall be exactly in the centre of the slide, and also 
 if possible of the thin glass square or cover ; round or 
 oval labels of white gummed paper must then be 
 placed at the top and bottom of the slide, and the 
 name and date Avritten thereon (see Pig. 52). 
 
 Slide 3. Scale of Roach (Lenciscns rntilns).- Take 
 a few scales from this or any other common fish, place 
 them in a weak solution of potass for a few hours, so 
 as to loosen the remaining pieces of membrane and 
 pigment cells ; then put them into one of the small 
 white porcelain saucers, and with the hog's hair brush 
 gently brush the remaining matter from them ; put 
 them in a basin of warm water for half an hour and 
 wash, then transfer them to a glass slip, cover with 
 another, put the slips between an American paper clip 
 and leave until dry. As the object is rather thick 
 and requires a cell, cut a piece of cardboard seven- 
 eighths of an inch square, punch a hole exactly in the 
 centre, and cement it to a glass slip with gold size 
 
\ 
 
MICROSCOPIC MOUNTING. 61 
 
 cement (see Recipe 68) ; place the object in centre of 
 this cell, and round the edges of the thin glass cover, 
 which should he f ths of an inch square, draw a thin 
 line of the same cement ; then place this cover on to 
 the cardboard cell and let it remain until thoroughly 
 dry, which will be in about two days ; brush a thin 
 layer of the sealing-wax varnish (see Recipe 7) all 
 round the edges of the cell, and cover with the paper 
 and ornamented cover as before described. 
 
 Slide 4. Diatoms (Diatoma vulgar e) . We will treat 
 this object in a slightly different manner, giving the 
 process of mounting and finishing with the turn table. 
 This object may be obtained in nearly every wayside 
 pond and pool, and for the method of collecting it, 
 and also other species of diatoms, see Chapter 6. 
 On a glass slip, ground edge (see Eig. 53, plate 2), 
 turn a circle with a brush charged with the india- 
 rubber cement (see Recipe 5) ; in doing this, use 
 Dr. Matthews' turn table (see description, &c., Eig. 5, 
 Chapter 1). Place the slide under a bell glass, so 
 that the cement may get nearly dry. In the mean- 
 while take a drop of the distilled water containing the 
 diatoms (see Chapter 5), and evaporate it on one 
 of the small glass circles. Use size three-eighths or 
 four-eighths of an inch, place this with the diatoms 
 inside, on the ring of cement, which should be nearly 
 dry (see Eig. 54, Plate 2) ; then with a small 
 camel's hair brush, charged with a very small quantity 
 of the india-rubber cement, paint round the edge of 
 the thin glass circle a thin layer of the cement, and 
 let the whole remain until quite dry, say one or two 
 days. When dry lay another thin layer over the last 
 only use the turn-table this time dry, and repeat 
 
62 A MANUAL OP 
 
 the process until a nice even ring of cement is formed, 
 then finish with one coating of Berlin black varnish, 
 or use gold size mixed with lampblack. I find that a 
 good body is made by putting a small quantity of 
 gum dammar varnish to the Berlin or Brunswick black ; 
 it dries well, and takes off the brittle properties of the 
 Brunswick black, which is very liable to fly when dry. 
 It may now be labelled, the name and date written, 
 &c. (see Pig, 55, Plate 2). 
 
 Slide 5. Section of Human J3one. Place a piece of 
 this or any other bone between the plate and the 
 screw of the holding screw (see Pig. 6) ; then with 
 the fine saw (Pig, 22) cut as thin a section as possible. 
 Take this section and cement it to one end of a glass 
 slip with Canada balsam cement (see Recipe 69), then 
 place the slip in the holding screw, and with a coarse 
 file, file it until it is moderately thin, then use a finer 
 toothed file for a short time, then warm the balsam 
 and remove the section, which again cement to the 
 glass slip on the side that has been ground ; when fixed, 
 repeat the process on the other side until it is thin 
 enough to show the structure of the bone when placed 
 under the microscope. Soak in ether or benzole for 
 ten or fifteen minutes to remove all grease from the 
 section ; polish on a small marble slab with Tripoli 
 powder and water ; when sufficiently polished, well 
 wash in warm water, and place between two slips 
 until thoroughly dry, after which it must be removed 
 to a square cardboard cell in which a hole has been 
 punched out (see Pigs. 56 and 57). The thin glass 
 cover may then be cemented to the cell, in the same 
 manner as described in mounting the wing of the 
 butterfly, after which it must be covered, labelled, and 
 named as usual. 
 
2, 
 
MICROSCOPIC MOUNTING. 63 
 
 Slide 6. Pollen Bird's Foot Trefoil (Lotus cornicu- 
 latus). The process of preparation for mounting this 
 object is quite easy, the only care to be taken is 
 that the object is thoroughly dry, which it will be if 
 the rules for the collection and rough preservation, as 
 described in Chapter 6, have been duly followed. It 
 may be mounted in the same manner as the diatom 
 (Diatoma vulgar e), with the exception, of course, 
 that the pollen must be placed quite dry on the centre 
 of the thin glass circle, after which the process may 
 be followed exactly. 
 
 Slide 7. Spores of an Equisetum (Equisetum telma- 
 teia). It is as well to mount this in a temporary 
 manner, as the chief characteristic of the spores is the 
 contraction of the four elators or threads under the 
 influence of even a slight degree of moisture, and as 
 this moisture evaporates the elaters uncurl, generally 
 with some degree of force, so as to cause the spores 
 to spring about in a remarkably life-like manner. A 
 cardboard cell is best used with a square thin glass 
 cover fitted to it, having a small hinge of thin paper. 
 When it is desired to observe the movements of the 
 spores the thin glass cover may be turned back, and 
 the slide placed on the stage of the microscope. If a 
 slight current of breath is then directed upon the open 
 cell the spores may be seen to move as if endowed with 
 life. When finished with, the thin glass cover may 
 be kept in its place with a small elastic band passed 
 over the slide, after which a label may be attached at 
 one end of the slide, bearing on it the name and date. 
 It may then be placed in the cabinet or rack box with 
 the other subjects. 
 
 Slide 8. Transverse Section of Rush (Juncus com- 
 
64 A MANUAL OF 
 
 munis). A piece of the stem of this rush, about 1^ in. 
 in length must be placed in melted wax until it is 
 well saturated with it. In doing this one of the small 
 white porcelain saucers must be used, and the wax 
 kept at the melting point with the aid of the hot- water 
 bath described in Chapter 1, paragraph 53. "When, 
 the piece of rush is well saturated with the wax it 
 must be taken out ; and, when cold and well set, thin 
 sections may be cut from it with a scalpel. To separate 
 the wax from these sections they must be soaked in 
 benzole or ether until it is thoroughly dissolved. To 
 be quite certain of this the section had better be put 
 into some fresh benzole, even after it appears to be 
 quite freed from the wax ; then dry in the apparatus 
 for drying objects (Pig. 27), after which it may be 
 mounted in the same manner as the diatoms (Diatoma 
 vulgar e), only great care must be taken that the 
 varnish cell is deep enough for the section ; care also 
 must be taken in placing the first thin layer of cement 
 so that it may not run into the cell. A thread passed 
 round, just under the cover, will be found useful to 
 prevent this. Finish as usual. The method of pre- 
 paration used for this section must be followed in 
 nearly all sections that are taken from cellular or 
 porous parts of plants, especially where they do not 
 contain much water, as in elder and other piths, &c. 
 In section of fruits, vegetables, &c., and where the 
 substance is soft and succulent, the support of the 
 wax is not required, the cells being so closely together 
 that they support each other. 
 
 Slide 9. Transverse Section of Oak ( Quercus robur] , 
 For the exact method of cutting sections of woods, 
 see Chapter 5, also paragraph 3. After the section is 
 
MICROSCOPIC MOUNTING. 65 
 
 cut it must be mounted in a paper or cardboard cell, 
 in the same manner as described for mounting the 
 * wing of the butterfly. 
 
 Slide 10. Cuticle of Ivy (Heeler a helix). For the 
 methods of separating this and other cuticles of leaves, 
 see Chapter 5. It may be mounted as follows : After 
 the cuticle has been separated from the leaf, float it in 
 a white saucer, then place one end of a ground edge 
 slip under the cuticle whilst it is floating in the water, 
 then gently guide it up the glass slip with a camel's 
 hair brush until it is quite in the centre of the cell 
 (see Pig. 53, Plate 2). All the water may then be 
 drained from it ; then place it to dry under a small 
 bell glass. In some cases it will be found to curl up 
 from the glass when dry. "When this is the case it is 
 as well to mix a small quantity of gum water with the 
 water that is used for floating the cuticle this will 
 make it adhere. If the glass is at all dirty round the 
 edges of the cuticle, clean it with a damp camel's hair 
 brush, then finish the slide in the same manner as 
 described for mounting the diatom (Slide 4). 
 
 Slide 11. Monopetalous Corolla of Pimpernel 
 (Anagallis arvensis). Dry this monopetalous corolla 
 in the same manner as described for drying petals in 
 Chapter 5 : after which it must be mounted and 
 finished in the same way as Slides 1 and 2 (see 
 Plate 1, Pigs. 49, 50, 51, 52). 
 
 Slide 12. Sulphate of Lime (So 2 Cao /A ). A solution 
 of this salt is taken at its full strength, which is the 
 exception to the general rule, as crystals form, in 
 greater beauty and regularity if a lesser strength than 
 a saturated solution is used. A drop from this is 
 placed with the pipette, in the centre of a cell like 
 
 F 
 
66 A MANUAL OF 
 
 Pig. 53 ; it must then be allowed to evaporate naturally. 
 When needle-like crystals of the sulphate of lime are 
 formed, the slide may then be finished in the same 
 manner as Slide 4. For future information in regard 
 to forming various crystals, see Chapter 5. 
 
 In mounting objects by this method, great care 
 should be taken that the object is perfectly dry before 
 it is mounted. Such as leaves, petals, &c., may be 
 dried as described in Chapter 6; others, like pollen, 
 are best dried naturally, except when they are mounted 
 with the anther and stamens, when the use of the 
 drying apparatus (Pig. 27) is the best mode of treat- 
 ment. If the student has sufficient of the material 
 that he is about to mount, it is as well to put a small 
 quantity into one of the small test tubes, or into one 
 of the test bottles these must be previously quite 
 clean and dry then place it on the hot plate, when if 
 any moisture occurs on the inside of the bottle or 
 tube, of course it is not dry. And even such a small 
 amount of moisture will nearly always cause fungoid 
 growths on the object, or at least on the inside of the 
 cell in which they are mounted. It is always the best 
 plan with transparent objects, when mounted dry, to 
 keep them in the centre of the cell by the pressure of 
 the thin glass cover alone, but occasionally this is 
 almost impossible, in which case gum water made 
 from the very best white gum Arabic, and well filtered 
 through blotting paper is the substance generally 
 used. The plan is this : A small drop, less in size 
 than the object, is placed in the centre of the cell ; it 
 must then be allowed to dry, after which one of the 
 smallest camel's hair pencils or brushes must be 
 dipped in water, and the surface of the drop of gum 
 
MICROSCOPIC MOUNTING. 67 
 
 moistened sufficiently to hold the object which is 
 placed on it. Care must be taken that it is thoroughly 
 dry and well fixed ; it may then be finished as usual. 
 In mounting objects dry, care must be taken that 
 both the glass slip and the thin glass cover are per- 
 fectly dry and clean. Many objects, such as diatoms, 
 scales of insects, many pollens, &c., do not require to 
 be fixed to the glass in any way, as they possess great 
 holding power in themselves. "When varnish or 
 cemant cells are made, it is always the best plan to do 
 a large quantity at one time, say five or six dozen, 
 for as well as its being a saving of time by the 
 time one or two dozen have been turned, the hand 
 acquires greater skill and nicety ; and again, by the 
 time six dozen are done, if required, the first may be 
 taken, and the cell made deeper by the application of 
 another layer of cement or varnish. The cells that I 
 find the best for dry mounting, are cement and varnish 
 for shallow cells, with a slight ring of paper placed on 
 them when nearly dry. I find this prevents the 
 varnish running in after the thin glass cover is 
 applied ; I also often use a small piece of thread for 
 the same purpose. Por thicker cells, use cardboard, 
 if paper covers are to be used : if not, the ebonite, 
 glass, metal, or india-rubber rings form the best cells. 
 Gutta-percha I do not recommend for use in the 
 form of cells. Especial care should be taken that all 
 cells should be well fixed to the glass slip. 
 
 61. Dry Opaque Mounting. We will now take the 
 remainder of the glass slips and thin glass covers ; 
 clean them well and proceed with the twelve opaque 
 objects as follows : 
 
 Slide 13. Foraminifera from sea-sand. E.E. 
 
 p 2 
 
68 A MANUAL OF 
 
 Slide 14. Spines of a brittle star-fish (Ophiocoma 
 rosulci). R.E. 
 
 Slide 15. Spore cases of a fern (Poly podium mil- 
 (/are). Wooden slip. 
 
 Slide 16. Stamens and pollen of the mallow (Malva 
 sylvestris). G.E. 
 
 Slide 17. Seeds of red campion or lychnis (Lychnis 
 dioica). G.E. 
 
 Slide 18. Eggs of a butterfly common garden 
 white (Pieris rapce). G. or R.E. 
 
 Slide 19. Palate Periwinkle (Litorina litorea). 
 E.E. 
 
 Slide 20. Pollen of convolvulus (Calystegia se- 
 pium). R.E. 
 
 Slide 21. Peristomes and capsules of a moss (Hyp- 
 num rutdbulum). G.E. 
 
 Slide 22. A British weevil, often called the British 
 diamond beetle (Polydrosus perygonialis.} R.E. 
 
 Slide 23. A Lichen (Parmelia parietina). G.E. 
 
 Slide 24. Crystals of silver. R.E. 
 
 Slide 13. Foramwifera, from Sea-sand. The pro- 
 cess of cleaning foraminifera is described in Chapter 5, 
 The best method of dry mounting when an opaque 
 view is required is to mount them as shown at 
 Eig. 56, Plate 2. This plan allows for their being 
 seen with the parabolic reflector and Lieberkulm 
 combined. The method is as follows : Take a 
 rough edge slip, centre it in the Matthews' turn 
 table (Eig. 5) ; then, with Berlin black varnish, 
 Recipe 70, or any other good black varnish, Recipe 11, 
 &c. ; turn a disc of the varnish exactly in the centre 
 of the slip (see Eig. 56) ; allow this to dry ; then, 
 with the gold size cement, Recipe 68, fasten a card- 
 
MICROSCOPIC MOUNTING. 69 
 
 board cell, so that the disc of varnish may be exactly 
 in the centre of this cell ; allow this to dry, and with 
 a fine camel's hair brush gently lay a thin layer of the 
 cement, Recipe 3 ; allow this to dry slightly (it never 
 gets thoroughly hard) ; then place the foraminifera 
 in the exact position that you* require, let the slide 
 stand under glass for about twenty-four hours to 
 dry; cement the thin glass cover on with the gold 
 size cement previously mentioned ; cover and finish 
 as usual. 
 
 Slide 14. Spines of a Brittle Star-fish (Ophiocoma 
 rosula). After the spines have been well cleaned and 
 dried (see the process for cleaning spines and spiculse, 
 Chapter 5) they may be mounted in the following 
 manner : Cut a slip of black paper If th of an inch 
 long by ^th of an inch wide ; it is as well to cut a few 
 dozen this size ; slightly touch each end of the black 
 side with gum and damp the centre, then lay it on the 
 ground edge slip in the manner as sliown in Pig. 57 ; 
 place this under slight pressure, so as to keep the 
 paper smooth whilst drying ; when dry, cement to the 
 other side of the glass slip a cardboard cell (Eig. 57). 
 In doing this, use the gold size cement; when dry 
 place in the centre of the cell a small quantity of 
 cement (see Recipe 2), which has been previously 
 coloured to a sandy tint; slightly touch the cement 
 with the soldering rod, and fix the spines immedi- 
 ately, or the gum cement (Recipe 3) may be used 
 instead ; fix the thin glass cover on, and finish as 
 usual. 
 
 Slide 15. Spore Cases of a Fern (Poly podium vul- 
 gar e). Many persons prefer mounting their dry 
 opaque objects on wooden slides, which are now 
 
70 A MANUAL OF 
 
 made and sold in large quantities. Fig. 58, Plate 3, 
 shows this object as it appears when mounted in one 
 of these slides. For objects that do not require much 
 care, this method is one of the best. The piece of 
 fern, after it has been thoroughly dried by pressure 
 in the usual manner, has only to be fixed to the 
 bottom of the cell, the thin glass circular cover 
 applied, a slight coating or ring of the gold size 
 cement (Recipe 68) painted round it, and the paper 
 ring cemented with gum, so as to hide the edge of the 
 thin glass cover ; it only then requires to be labelled 
 and named. From these remarks the student will see 
 that the process is extremely easy. 
 
 Slide 16. Stamens and Pollen of Mallow (Malva 
 sylvestris). After this object has been thoroughly 
 dried in the object-holder of the drying apparatus 
 (see Pig. 27, also Chapter 5), it may be mounted 
 as follows : Take a ground edge slip, centre it 
 in the Matthews' turn-table (Fig. 5), and with a 
 brush, charged with the Berlin black varnish, turn a 
 disc about four-eighths of an inch in diameter ; allow 
 this to dry, then cement one of the ebonite cells 
 to the glass slip with the india-rubber cement (Recipe 
 5), so that the varnish disc may form the opaque 
 bottom of the cell (see Fig. 59). When dry, place in 
 the centre of this cell a small piece of a cement, 
 previously coloured in purple and pink shading to 
 resemble the petal of the flower (see Recipe 2) ; but 
 the cement need not show if care is taken to use a 
 small quantity only. Place the stamens on this 
 drop of coloured cement, touch the edge of the thin 
 glass cover with gold size and let it nearly dry, then 
 place it on the cell, and when thoroughly dry which 
 
Teg 60 
 
 62 
 
MICROSCOPIC MOUNTING. 71 
 
 will be in about twenty-four hours if the gold size is 
 good paint round the edge a very thin layer of gum 
 and whiting (Recipe 71). Let this dry; with the 
 turn-table turn another layer of gold size let it dry ; 
 and if, after this, the surface is not even, another 
 coating of varnish must be applied. Pinish with a 
 coating of Berlin black, put on with the turn-table. 
 When dry, label and name as usual. 
 
 Slide 17. Seeds of Red Campion or Lychnis (Lychnis 
 dioica). This object may be mounted in one of the 
 wooden slides, as described for slide 15, or in a cell 
 like the preceding object; in which case, perhaps, it 
 is advisable to make, in the centre of the cell, a small 
 cup-like body out of the cement (Recipe 2), which has 
 been previously coloured a whitish green; or, if the 
 manipulator prefers it, all these opaque objects may be 
 fixed with the gum and glycerine (Recipe 3); the slide 
 may then be finished as described for Slide 16. 
 
 Slide 18. Eggs of a Butterfly, Common Gar den JJ^hite 
 (Pieris rapce). Eggs of moths and butterflies, as men- 
 tioned in Chapter 5, show best when mounted opaquely, 
 especially the large ones, after the larvae has forced 
 its way out of the shell. The smaller ones may be 
 killed by the action of hydrocloric acid (if previously 
 pricked, whilst in the egg state), but the former method. 
 I find to be the best. A small drop of cement 
 (Recipe 2), coloured bJack, should be placed in the 
 centre of the cell, and the eggs fixed to it by a minute 
 drop of gold size thickened with lampblack; or the 
 eggs may be mounted on a small disc of cardboard 
 Tg-th. of an inch in diameter, previously fixed to the 
 centre of the cell, and coloured a dull black with 
 Indian ink. The eggs may then be mounted on this 
 
72 A MANUAL OF 
 
 with gum water, using an extremely fine camel's hair 
 brush. Mnish in the same manner as Slide 16. 
 
 Slide 19. Palate Periicmkle (Litorina litorea).- 
 After this palate has been, dissected from the mollusc, 
 as described in Chapter 5, and after it has been well 
 washed, it must be mounted as follows : Take a 
 rough edge slip, which already has a piece of black 
 paper fixed on one side (see description, Slide 14), 
 place the palate on the other and clean side, stretch it 
 exactly across the middle of the glass slip parallel to 
 its length ; at each end of the palate, and before it is 
 dry, put a drop of the india-rubber cement (Ilecipe 5). 
 Let it dry thoroughly ; then take a thin glass cover, 
 1-J inch by f inch, to each corner of this, cement a 
 small piece of cardboard with the gold size cement 
 (Recipe 68) ; when thoroughly dry, cement this cover 
 over the palate by touching the cardboard with the 
 cement and immediately fixing it to the glass slip, so 
 that the palate may come exactly in the centre of the 
 cover, parallel with its length, The sides that are 
 left open must then be closed with the cement (Ilecipe 
 5 or 6), using the soldering rod in doing this. Make the 
 edge of this cement neat and smooth, after which the 
 slide maybe covered in the same manner as Slide 14. 
 
 Slid-e 20. Pollen of Convolvulus (Calystegiasepium). 
 This object, after it has been thoroughly dried, as 
 described in Chapter 5, may be mounted in pre- 
 cisely the same manner as Slide 14, only, care must 
 be taken that when the cement is laid upon the black 
 varnish disc that an extremely thin layer only is put 
 on, for if this is not attended to, the pollen will absorb 
 the cement and be spoilt. Another and perhaps better 
 plan is to use a black paper disc, cement this to the 
 
MICROSCOPIC MOUNTING. 73 
 
 centre of the cell, and cover with a very thin layer of 
 gum; when nearly dry, scatter the pollen over it; 
 when quite dry, cement the thin glass cover over all, 
 and finish as usual. 
 
 Slide 21. C apsides and Peristomes of a Moss (Hyptmm 
 rutabidum) These objects show best when mounted 
 on the cement (Recipe 2), which has been previously 
 coloured an olive green. Place a small quantity of 
 this in the centre of a cell, in the same manner as de- 
 scribed for Slide 16 (see Eig. 59), using the soldering 
 rod to slightly melt the surface of the cement, after 
 which the capsules must be fixed to it immediately. 
 It may then be finished in the same manner as 
 Slide 16. 
 
 Slide 22. A British Weevil, often called the British 
 Diamond Beetle (Polydrosus pterygonialis). This 
 specimen ought to have been previously fixed, with its 
 legs and antennae placed in their proper position, on a 
 gummed slip of card (see Chapter 6). If this has 
 been properly done, the gurn may be moistened with 
 a fine camel's hair brush and the insect transferred 
 to the centre of a cardboard cell, to the bottom 
 of which a disc of white gummed paper has been 
 added (use gum tragacanth). When quite dry, the thin 
 glass cover must be cemented on, and the slide finished 
 as usual. 
 
 Slide 23. A Lichen (Parmelia parietina). This 
 object does not require any previous preparation; simply 
 dry it in its natural position. Cement it to the centre 
 of an opaque cell with the cement (Recipe 2), then 
 follow the same process as described for Slide 16. 
 After which, place name and date on the label as 
 usual. 
 
74 A MANUAL OF 
 
 Slide 24. Crystals of Silver. This object is one of 
 the most beautiful of all the opaque objects. The 
 best method of making the crystals is by using the 
 galvanic battery, a full description of the process of 
 which is given in Chapter 7. An easier method is to 
 take a piece of copper foil, place it on a glass slip, 
 make a slight wall of wax round it, and into this cell 
 pour a small quantity of nitrate of silver. When the 
 crystals are properly formed, float them on the surface 
 of a basin of water, then take a clean glass slip and 
 gently place it under the crystals; raise one end of 
 the slip gradually, so as to let the water run off, 
 or the silver film may be washed on the slip. 
 When dry, mount in a cell, in the same manner as 
 described for Slide 19, after which finish and label 
 as usual. 
 
 62. The following objects show well when mounted 
 by the dry process. The letters D.T. signify Dry Trans- 
 parent method, and D.O. Dry Opaque : 
 
 Human bone, D.T; elephant's bone (Elephas Indicus), 
 D.T.; horse (jEquuscaballus),T>.T.' 9 ox (J3os domesticus), 
 D.T.; monkey, D.T.; saw fish (Pristis), D.T.; rat (Mus 
 decumanus), D.T.; ostrich (Strothio camelus), D.T.; toad 
 (JBufo vulgaris), D.T.; &c. 
 
 The following sections of teeth are good and typical. 
 Make vertical and transverse sections : 
 
 Beaver (Castor fiber], D.T. ; human, D.T. ; horse 
 (Equus caballus), D.T.; eagle r&y(Myliobate8) 9 D.T.; ox 
 (JBos domesticus), D.T.; rabbit (Lepus cuniculus), D.T. ; 
 saw fish (Pristis), D.T.; tiger (Felis tigris), D.T.; cro- 
 codile ( Crocodilus), D.T. ; kangaroo ( Macropus Parryi), 
 D.T.; seal (Phoca vitulina), D.T.; porcupine (Hystrix 
 cristata), D.T.; pike (Esox lucius], D.T.; lemur (Lemur 
 
MICROSCOPIC MOUNTING. 75 
 
 ruber), D.T.; bat ( Vesper tilwpipistrelius)> D.T.; Hedge- 
 hog (Erinaceous Europceus), D.T.; mole (Talpa 
 Europcea), D.T.; black bear (Ursus Americanus], 
 D.T.; &c. 
 
 Ctenoid scale of sole (Solea vulgar is), D.T.; cycloid 
 scale of eel (Angvilla acwtirostris) , D.T.; ganoid scales 
 of sturgeon (Acipenser sturio), D.T.; placoid scale of 
 shark (Scymnm bovealis), D.T.; spiculse of various 
 species of Gorgonia, D.O. ; spiculae of Geodia barreta and 
 many other species of sponges, D.T. and D.O.; spines of 
 Spatangus, various species of Echinus, brittle and other 
 star fishes, D.O. ; diatoms, many species, D.T. ; scales 
 of butterflies, D.T. ; scales of butterflies and moths in 
 situ, on the wing, D.O. ; foraminifera, chiefly D.O. ; in 
 some few cases where very transparent, D.T. ; Polycys- 
 tina, D.O. ; sections of granites, marbles, limestones, 
 &c., chiefly D.T. ; weevils, beetles and other insects 
 having brilliant scales and markings on the elytra or 
 wing cases and other parts of the body, chiefly D.O. ; 
 heads of butterflies, moths, &c., D.O. ; eyes of butter- 
 flies, flies, bees, &c., if before dissection, D.O. ; after 
 dissection generally D.T. ; gizzard of crickets, and also 
 beetles, D.O. ; legs and feet of beetles, D.O. ; nests of 
 small spiders, D.O. ; galls (minute) and tracts of leaf- 
 mining insects, &c., D.O. ; a few spiracles, D.O. ; elytra 
 of beetles, such as diamond beetle, &c., D.O. ; Diatom- 
 aceas or seaweed, and other algae, D.O.; shell of orbito- 
 lite, D.O. ; feathers of humming-bird, peacock, and 
 other birds, D.O. ; Elustra foliacea, and a few other 
 zoophytes, D.O.; palates of periwinkle, whelk, trochus, 
 limpet, &c., D.O. ; peacock and ruby copper ore, D.O. ; 
 gold dust and small nuggets, D.O. ; calyx of deutzia, 
 with silicious hairs, D.O.; pollens, mallow, convolvulus 
 
76 A MANUAL OF 
 
 D.O. ; also all large pollens, and smaller kinds if trans- 
 parent, D.T. see Chapter 5 ; some Haphides, D.O. ; 
 capsules and peristomes of Hypnum, Tortula, and 
 many other species of moss, D.O.; skeleton leaves, D.O. ; 
 section of clematis and other stems, D.O. ; seeds- 
 Antirrhinum, Digitalis, Verbascum, Portulacca, and 
 many others, D.O. ; seeds of orchis maculata, D.O. and 
 D.T. ; a few algae, marine and freshwater, D.T. ; spores 
 of equisetum, and also ferns, D.O.; spores of equisetum, 
 D.T. ; spores of fungi, D.T. ; moulds, "brands, rusts, 
 cluster cups, &c., Loth D.O. and D.T. ; sections of spine 
 hedgehog, D.T. ; and other spines, bone of cuttlefish, 
 D.O.; embryo oysters, D.O.; scales offish, both D.O. and 
 D.T. ; also, in situ, in the skin ; starches, D.T. ; cuticle 
 of many leaves and petals, best D.T. ; spiral vascular 
 tissue from rhubarb, D.T. ; scales eleagnus, D.O.; sting 
 of nettle, D.O. ; frond Tunb ridge film fern (Hymen- 
 ophyllwn Turibridgeme) ; sections of woods, many sec- 
 tions are best dry, D.T. ; others in balsam, &c. See 
 Chapter 5. Hairs of plants, generally D.T. ; lichens, 
 generally D.O. ; some acari, D.T. ; but generally in 
 glycerine, &c. see Chapter 5 ; sections of rice-paper 
 and other forms of pith, D.T. ; sections of rush, D.T.; 
 a few crystals, D.T.; &c. This short list will give an 
 idea of the sort of objects that require to be mounted 
 dry. It would be an impossibility to name all the 
 objects separately, but for a general guide in the 
 examination of an object with respect to the best 
 method of mounting it it is as well to look at it 
 first as a transparent object ; if too thick, then look 
 at it as an opaque object; if not well defined and 
 distinct, try fluid mounting ; if this fails to render it 
 transparent, try balsam or dammar varnish, But the 
 
MICROSCOPIC MOUNTING. 77 
 
 student must bear in mind that each object generally 
 requires a separate treatment according to its nature ; 
 which knowledge is, of course, best gained by practice. 
 In placing any object into the position in which it is 
 required to be mounted, always use the forceps ; never, 
 in any case, handle objects, as they are mostly so 
 delicate that they will not bear handling. 
 
 63. When objects are mounted by the opaque pro- 
 cess, thin sheets of variously coloured gutta-percha 
 will be found useful, especially for insect preparations 
 (E/ecipe 66.) Occasionally, slight fungoid growths 
 arise from using these sheets of gutta-percha, but if 
 corrosive sublimate (HgCl 2 ) is added whilst mixing 
 the colour, this will be prevented. 
 
 64. Many objects, such as the scales of fish, &c., 
 require to be dried under pressure. The American 
 paper clips give sufiicicnt pressure for most objects ; 
 but when the specimen is very thick, and greater 
 pressure is required, the holding-screw (Tig. 6) will 
 be found useful. When the object is only require d to 
 be kept in its place whilst drying, as for example a 
 cuticle, a thin glass cover should be applied, and a 
 moderately strong india-rubber band brought over 
 the slide so as to 'confine the thin glass cover in its 
 place. 
 
 65. Hairs. Scales, &c., of plants are of ten mounted 
 dry ; but to show them well, it is best to mount them 
 in their natural position on the cuticle of the leaf ; to 
 do so they should be mounted D.O. ; they should also 
 be mounted D.T. ; and in fluid and balsam; see Chapter 
 3, Chapter 4, and Chapter 5. 
 
 66. When zoophytes and seaweeds are mounted dry, 
 care should be taken that they are thoroughly freed 
 
78 A MANUAL OF 
 
 from sea-salt ; to do this, wash well in water, and in 
 weak acetic acid, and lastly in warm water to free 
 them from the acid. 
 
 67. Many opaque ohjects show well when mounted 
 in a dry transparent cell, and the diaphraghm brought 
 under it so as to form a dark background, especially 
 if the object is semi-opaque. This method of 
 mounting will be found the best, as it can then be 
 seen both by transmitted and reflected light, and 
 by this means the structure will be more fully inves- 
 tigated. Another way to mount opaque objects dry 
 is to grind a hollow cell in the centre of a thick, 
 rough-edge slip. Fix the specimen to the bottom of 
 this cell with a cement, either Recipe 1 or 2, Appendix; 
 when fixed, cover with a thin glass square or circle, 
 and allow a very small drop of the Canada balsam 
 and chloroform to run in between the glasses by 
 capillary attraction ; but care should be taken that 
 too much is not put, or it. will run into the cell and 
 spoil the object. When quite dry, the slide may 
 be covered as usual ; by this plan all moisture 
 is kept from the object, and fungoid growths pre- 
 vented. 
 
 68. A good plan for labelling dry and other objects 
 when they are mounted on ground edge slips (Figs. 
 53, 54, &c.), is to punch some circles out of very 
 thin talc ; cover the edge of the glass slip with a thin 
 layer of gilder's whiting and gum water; when dry, 
 write on this with common ink; let it dry, put a 
 very small drop of Canada balsam on to it ; cover 
 with a circle of thin talc, and allow all to dry ; then 
 clean the edges with benzole and water mixed. This 
 plan will be found a good one legible and lasting 
 
MICROSCOPIC MOUNTING. 79 
 
 being superior to writing on ordinary white labels, as 
 these often peel off or get dirty. This kind of label 
 can of course only be used when the rest of the glass 
 is exposed, as in the case of mounting with ground- 
 edge slips. 
 
80 A MANUAL OF 
 
 CHAPTER III. 
 
 THE PREPARATION BY THE CANADA BALSAM AND 
 DAMMAR PROCESSES. 
 
 69. There are many objects such as insect dissec- 
 tions and polarising crystals, &c., that cannot be 
 mounted in any medium but Canada balsam, though 
 when the dammar varnish comes to be better known, 
 I believe for many of them it will supersede the 
 balsam ; but, no doubt, Canada balsam will never be 
 entirely replaced by any medium, for it has certain 
 properties which will always recommend it not but 
 what the dammar is best for general use, it dries 
 better than the balsam, which alone will make it the 
 most favourable medium for the microscopist. 
 
 70. As we followed the plan of taking a series of 
 common typical objects in the process of dry mounting, 
 it will be as well to follow the same course in the 
 method of mounting by the Canada balsam and 
 dammar processes. It is much better to keep both the 
 balsam and the dammar in the collapsible tubes men- 
 tioned in Chapter 1, Eig. 65, Plate 4, for as well 
 as being the cleanest plan, the balsam keeps much 
 better than in a corked bottle, Eig. 66, Plate 4 ; the 
 required quantity is also much easier obtained. Take 
 twelve clean slips, rough edge, and the following are 
 
MICROSCOPIC MOUNTING. 81 
 
 the twelve objects, the process of mounting in Canada 
 balsam taking nine of them, the other three being by 
 the dammar process. 
 
 Slide 25. Human flea (Pulex irritans). 
 
 Slide 26. Palate of whelk (JBuccinum undatum). 
 
 Slide 27. Crystals of chlorate of potass (ClOoKo). 
 
 Slide 23. Raphides in onion (Allium cepa). 
 
 Slide 29. Potato starch (Solcwmm tuber osimi). 
 
 Slide 30. Silicious cuticle of equisetum (Equisetum 
 hyemale) . 
 
 Slide 31. Fibres of wool (Ovis aries). 
 
 Slide 32. Fibres of cotton (Gossypium herbaceum). 
 
 Slide 33. Spiracle of water-beetle (Dytiscus margi- 
 nalis). 
 
 Slide 34. Bramble brand (Aregma bulbosum}. 
 
 Slide 35. Spores and sporanges of brake fern 
 (Pteris aquilina}. 
 
 Slide 36. Foraminifera from chalk. 
 
 Slide 25. Human Flea (Pulex irritans). This slide 
 illustrates the method of mounting most of the small 
 insects. The flea must be placed in the liquor potass, 
 and left in it for a few days ; when tolerably soft, 
 place it between two t glass slips and gradually squeeze 
 out the contents of the abdomen, &c, ; use very slight 
 pressure at first, and if .it feels at all hard, it must be 
 replaced in the potass until soft, but if it is found that 
 the body gives way to the pressure, it may be in- 
 creased until all the matter is ejected ; then place it 
 in warm water for a quarter of an hour, after which 
 repeat the process until the insect is perfectly clean, it 
 may then be washed in warm water, or, what is much 
 better, silicic acid (for method of making which see 
 Recipe 9); this acid has an affinity for potash, turning 
 
 a 
 
82 A MANUAL Or 
 
 it into silicate of potass (SiKo 4 ), which substance is 
 very soluble in water ; then well wash in water, place 
 it between glass slips to dry, taking care that the slips 
 have been previously slightly greased, as this will 
 prevent the insect sticking to the slips when dry, 
 otherwise it often does, and some of its legs are lost 
 in consequence. "When quite dry, which will be in 
 two or three days if in a warm room, place it in a 
 small porcelain saucer full of turpentine, cover it 
 with a broken wine-glass, allow it to soak until quite 
 transparent, but do not let it be in the turpentine long 
 enough to lose its colour, transfer it to the centre of 
 a rough edge slip, and from the tube containing the 
 balsam (Pig. 65), drop one large drop on to it; then 
 cover with a square thin glass cover (Tig. 63, Plate 4), 
 and place the slide in the pressure apparatus (Pig, 29) 
 for a short time, so that most of the air bubbles are 
 forced out ; then put it in the drying apparatus, or on 
 the warm plate, as described in Chapter 1, paragraph 6. 
 When the balsam is quite set and hard, it may be 
 cleaned off with an old knife made slightly hot. 
 When all the superfluous balsam has thus been cleared 
 from the slide this is best done under water it may 
 be made quite clean with the aid of benzole or tur- 
 pentine, used with a rag kept for the purpose ; the 
 slide may then be covered and finished as described 
 for Slide 2, Chapter 2, and Pigs. 49, 50, 51, 52. If 
 the student does not care to use the silicic acid, 
 washing in warm water will do nearly as well, but I 
 prefer the acid. And again, after being well washed 
 in water, many manipulators prefer to transfer it to 
 spirit (methylated will do), and then take it out, 
 slightly drain it on paper, and transfer it to benzole, 
 
Fig 6< 
 
MICROSCOPIC MOUNTING. 83 
 
 from thence to the turpentine, and lastly balsam ; by 
 this process the object is never dry; it answers 
 tolerably well in many cases, but very great care is 
 required to free it from traces of the spirit by well 
 washing in the turpentine, which use slightly warm. 
 
 Slide 26. Palate of Whelk (Buccinum undatum) . 
 For the dissection of palates, refer to Chapter 5. 
 The palate must then be put into a test-tube with 
 a small quantity of potass, and boiled until clean, 
 which will take about ten or fifteen minues ; then 
 well wash in warm water to free it from the potass, 
 and place between two glass slips to dry ; but in this 
 case, give the required pressure with two india-rubber 
 bands passed over the slips, as the pressure of the 
 American paper clips is rather too great, and often 
 injures the teeth ; when quite dry, soak in turpentine, 
 using one of the small porcelain saucers ; when trans- 
 parent, transfer to the centre of a cell made as 
 follows : with a writing diamond cut 4 slips of thin 
 glass, two fths of an inch long, and -|th wide, and 
 two f tlis of an inch long and -^th wide, cement these 
 to the glass slip with marine glue, or the cement, 
 Recipe 72, so as to make a cell -Jths of an inch square 
 (see Pig. 64, plate 4) ; when quite dry, clean off from 
 the inside of the cell any superfluous cement ; after it 
 is quite clean, pour in a small quantity of turpentine, 
 but do not allow it to remain longer than two or three 
 minutes, then pour out. Now fill the cell with 
 Canada balsam, and in the centre, place the palate of 
 whelk ; moisten one side of a thin glass cover, exactly 
 -|ths of an inch square, with turpentine, and drop it 
 on to the balsam, so that all air-bubbles may be 
 excluded from the cell ; this is easily done if sufficient 
 
 o 2 
 
84 A MANUAL OF 
 
 balsam has been put into the cell. Place the slide in 
 the drying apparatus (Chapter 1, page 9) until dry, 
 then clean and cover as usual. 
 
 Slide 27. Crystals of Chlorate of Potass (ClO 2 Ko). 
 This is a very beautiful object for the polariscope, 
 when well mounted ; place a small quantity in the 
 test-tube, enough to occupy one part of a tube 
 graduated into six equal parts ; then pour in water 
 two parts, boil until the chlorate is dissolved, then 
 pour over glass slips : allow them to crystallize 
 gradually, and without the aid of artificial heat : 
 when quite dry, pick out the best of them, and again 
 the best one from these, then drop one drop of Canada 
 balsam on to the mass of crystals, and place the thin 
 glass cover on ; press gently, so as to squeeze the 
 superfluous balsam out, after which the balsam must 
 be allowed to dry gradually, for if forced with heat 
 the crystals would be spoilt ; when quite dry, which 
 will be in a few weeks if only just sufficient balsam has 
 been used, for the thinner the layer under the thin 
 glass cover, of course the quicker it dries, then cover 
 and label as usual. Some crystals require different 
 treatment and mounting (see Chapter 5). 
 
 Slide 28. Raphides in Onion (Allium cepa). These 
 Raphides, like most of those that are contained in the 
 sepals, cuticles, &c., of plants, only require to be 
 dried under pressure, and the piece of cuticle or sepal 
 soaked in turpentine, and mounted in balsam. If 
 the Haphides require to be tested with the re-agents, 
 to ascertain whether they are sulphate, oxalate, &c.. 
 of lime, they must previously be moistened witl 
 water, or glycerine (if glycerine re-agents are used), so 
 as to allow the re-agent to pass into the tissue of the 
 
MICROSCOPIC MOUNTING. 85 
 
 leaf, otherwise a slight difficulty in its passage would 
 occur ; but for further information in regard to the 
 testing of these bodies, see Chapter VII. Occasionally, 
 where the Eaphides are not required for the polari- 
 scope, they may be mounted in fluids, (see Chapter V.); 
 but if mounted in balsam, the slides may be dried in 
 the drying apparatus (Figs. 7, 8), and cleaned and 
 covered in the usual manner. 
 
 Slide 29. Potato Starch (Solarium tuberosum). I 
 have chosen this starch as it is the largest of all the 
 common starches, for though Tous-les-mois is larger, 
 it is not so easily obtained. The potato starch, on 
 account of its size, is therefore much easier to examine. 
 To obtain it pure as taken from the tubers (see Chapter 
 V.) take a small quantity of the dry starch on the tip of 
 a scalpel, and place it in the centre of the centred slips ; 
 then drop one drop of turpentine on to it allow it 
 nearly to evaporate ; then drop some Canada balsam 
 on to a thin glass cover, which place on the small 
 lump of starch, but which has been previously spread 
 evenly over the centre of the slip with a dissecting 
 needle, press the thin glass cover gently, and if it is 
 found that the starch lies too thickly in the centre, 
 move the thin glass cover round with a circular 
 motion ; this will distribute the granules of starch 
 better than any other plan. The balsam answers 
 very well for these objects, but dammar is much 
 better. If any air bubbles have got into the balsam 
 or dammar they need not worry the student, for if the 
 slide is placed in a warm place say on a window-shelf, 
 south aspect, or on the mantel over the fireplace it 
 will be found that they disappear entirely after a few 
 days. It does not matter whether the starch is 
 
86 A MANUAL Otf 
 
 mounted in balsam or dammar, it must not be dried 
 by the aid of artificial heat, or the granules of starch 
 will be spoilt ; but if good dammar or the Canada 
 balsam and chloroform, Recipe 13, is used, it will not 
 take very long to dry. When dry, the slide may be 
 cleaned from the superfluous balsam, and finished as 
 usual. Some starches are mounted dry, others in 
 fluid, &c., see Chapter 5. For the tests for starch, see 
 Chapter 7. 
 
 Slide 30. Silicious Cuticle ofEquisetum (IZquisetum 
 hyemale). After this cuticle has been separated with 
 nitric acid (NO 3 Ho) see Chapter 5 it must be well 
 washed in warm water. A clean glass slip must then 
 be taken, and the centre, where the piece of cuticle 
 will come, a very thin layer of mucilage, formed 
 from gum tragacanth, must be evenly spread, so that 
 the cuticle will fit on to it as nearly as possible. 
 On this, place the cuticle exactly in the position that 
 is required, as it will not be moved a^ain ; over this 
 place another glass slip, which has been previously 
 slightly greased to prevent it sticking ; then place the 
 slips between an American paper clip. When the 
 cuticle is quite dry, take the top slip of glass off, and 
 allow the cuticle to be well soaked with turpentine. 
 At the same time the edges of the piece of cuticle can 
 be cleaned and trimmed with a sharp scalpel. Drain 
 the superfluous turpentine off, and drop a small 
 quantity of balsam on to the cuticle, then cover with 
 a thin glass cover, and press the cover. Place the 
 slide to dry in the drying apparatus, Chapter 1, page 
 9 ; and, when dry, clean and cover as usual. The 
 cuticle may be mounted without the aid of the gum 
 tragacanth, but on drying it is very liable to curl up 
 
MICROSCOPIC MOUNTING. 87 
 
 and separate from the slip : the gum is used to prevent 
 this. The cuticle may also be mounted in a cell with 
 glycerine, &c., see cuticles, Chapter 5. This is a 
 magnificent object for the polariscope. 
 
 Slide 31. Fibres of Wool, Sheep (Ovis aries.) I 
 have taken this object, not on account of its beauty or 
 remarkable appearance, but from its structural charac- 
 teristics. Its felting power, as has lately been noticed, 
 no doubt proceeds from its sinuous nature, and not 
 from its but slightly imbricated surface, which is much 
 less than the hairs of either mouse, or common bat, 
 and other animals. Wool may generally be distin- 
 guished from cotton, &c., by its structural peculiar- 
 ities, see Pig. 129, Plate 11, and also by chemical 
 tests, &c., see Chapter 7. After being well washed in 
 warm water and dried, it may be further washed in 
 benzole, to free it from any grease, and soaked in 
 turpentine, and mounted in Canada balsam or dam- 
 mar ; dry in the dryin g apparatus, but use a gentle 
 heat. When quite dry, clean with benzole, and cover 
 as usual. For further information in regard to wool, 
 see Chapter 5. 
 
 Slide 32. Fibres of Cotton (Gossypium herbacemri). 
 -Vegetable fibres are generally distinguished from 
 animal, by potass having little action upon them ; 
 whereas, in the animal fibres, they are dissolved by 
 the potass, especially if a slight degree of heat is 
 used, see Chapter 5 and Chapter 7. Cotton may be 
 mounted in the same way as the wool, that is, if it is 
 required for the polariscope, with this exception, that 
 it does not want to be washed in benzole, being a 
 vegetable fibre, and in its pure state it contains no 
 grease. Like the wool it must be dried with a gentle 
 
88 A MANUAL OF 
 
 but continuous heat. Finish and cover in the same 
 manner, care being of course taken that the exact 
 kind of cotton, with the date of mounting, &c., be 
 correctly stated. 
 
 Slide 33. Spiracle of Water Beetle (Dyliscus 
 marginal**). For the proper method of dissection of 
 this and other spiracles, I must refer the student to 
 Chapter 5 ; and now take the opportunity to mention 
 that this is done to save undue repetition, as well as 
 the matter being placed in its proper position. After 
 the spiracle, therefore, has been dissected and well 
 washed, and in this case it is as well to pin the piece 
 containing the spiracle or spiracles to a piece of loaded 
 cork, which place in a saucer, and direct a fine stream 
 of water from the water-bottle Fig. 13, Chapter 1, 
 paragraph 10 on to it, so as to wash it thoroughly. 
 This is not immediately necessary, but if any dust or 
 dirt of any kind remain amongst the fine hairs sur- 
 rounding the orifice of the spiracle, by this process it 
 will be removed. When wanted, dry between two 
 slips of glass, which have been previously slightly 
 greased to prevent the skin and spiracle from sticking 
 to them. For pressure in drying, use an American 
 paper clip. "When dry, soak in turpentine until trans- 
 parent, and transfer to the centre of a clean ground 
 edge slip, drop a drop of balsam or dammar on to it, 
 cover with square thin glass cover, press it gently, 
 then place it in the drying apparatus, Chapter 1, 
 paragraph 6. When dry, finish as usual. 
 
 Slide 34. Bramble Brand (Aregma bulbosmn). 
 The best method of mounting this brand, so as to 
 show the spores well, is to take a fine section, by 
 cutting through the centre of a cluster of this brand, 
 
MICROSCOPIC MOUNTING. 89 
 
 and also right through the bramhle leaf ; as thin a 
 section as possible must be cut ; soak in turpentine 
 until the spores are quite transparent, which will be 
 in two or three days ; the section may then be trans- 
 ferred to a clean slip, and mounted in balsam or dam- 
 mar. Dammar is much the best for this object. The 
 chief difference in mounting, when using this varnish, 
 is to place the thin glass cover over the object, and 
 allow the dammar to flow in by capillary attraction. 
 This method has many advantages, especially when 
 the object is small and requires to be in the centre of 
 the slide; for in mounting with balsam, however 
 much care the learner takes, he will often find a great 
 difficulty in keeping his object in the right place ; but 
 by using the dammar this difficulty is avoided. Dry 
 the slide in the drying apparatus, Chapter 1, para- 
 graph 6. Use moderate heat. When quite dry, clean 
 with the knife and benzole, and finish as usual. 
 
 Slide 35. Spores and Sporanges of Brake Fern 
 (Pteris aquilina). The method of collecting these 
 spores is described in Chapter V. Take a small quan- 
 tity of the spores and spore- cases on the tip of a 
 scalpel, place them in the centre of a clean glass slip, 
 drop one drop of turpentine on to them, cover with a 
 thin glass cover, and let the dammar flow in by capil- 
 lary attraction; place the slide in the drying appa- 
 ratus to dry ; use moderate heat ; when dry finish as 
 usual. Most of these objects, if preferred, may be 
 mounted on ground edge slips, but if so, the circular 
 thin covers must be used, and when the balsam or 
 dammar is dry, clean with an old knife and benzole, 
 and finish the slide by turning a neat ring of Berlin 
 black varnish with the Matthews' turn-table, so that 
 
90 A MANUAL OF 
 
 the slide, when finished, will look like Pig. 55, 
 Plate 2. 
 
 Slide 36. Foraminifera from Chalk. Boil a small 
 lump of chalk in a test-tube with potass until it sepa- 
 rates in powder ; put this into an 8- ounce phial hottle 
 and fill with water ; fresh water must be added as long 
 as it comes away of a milky tint ; the deposit will 
 then consist chiefly of minute foraminifera, &c. ; take 
 a small quantity of this powder, place it in the centre 
 of a clean glass slip, then dry it over the spirit-lamp ; 
 when quite dry, drop a drop of turpentine on to it ; 
 drain the superfluous turpentine off; place a thin glass 
 cover over the foraminifera, and allow the dammar 
 to flow in by capillary action; dry in the drying 
 apparatus ; when quite dry, clean with an old knife 
 and benzole ; finish and cover as usual. 
 
 71. In mounting with Canada balsam or dammar, 
 it is always best to use the collapsible tubes men- 
 tioned in Chapter I,, for, as well as keeping cleaner 
 than in the stoppered glass bottles, as generally 
 recommended, the balsam also keeps in a much better 
 condition. Thin balsam is generally the best for 
 mounting purposes, as it dries quicker than when old 
 and thick. If, after it is bought, it is found to be 
 too thick, it may be diluted with benzole, turpentine, 
 or chloroform ; and if any cloudiness remains after 
 mixing, it will go off in a short time (see also recipe 13). 
 Before mounting any object in balsam, great care 
 must be taken that the object is thoroughly dry. To 
 make quite sure of this, the object, even after being 
 dried in the object-drier (Pig. 27), may be tested in a 
 tube (see Chapter II., under Slide 12.) Dampness is 
 known by a cloudiness in the balsam round the object. 
 
MICROSCOPIC MOUNTING. 91 
 
 If this occurs whilst drying the slide, extreme heat 
 will sometimes clear it ; but it is best, if the specimen 
 is valuable, to soak the slide in turpentine and re- 
 mount the object. 
 
 72. Air-bubbles, as I mentioned before, need not 
 trouble the student so much as they generally do, for 
 they will often disperse of their own accord ; but 
 if any difficulty is found, the slide must be placed in 
 tha air-pump (Pig. 30), and the air exhausted, by 
 which means the bubbles are gradually brought to the 
 surface and dispersed (see also Chapter I., para- 
 graph 27.) Foraminifera, and other objects which will 
 stand heat, may be cleared of air-bubbles by boiling 
 in turpentine. But although much mention is made 
 of turpentine as a useful and important medium in 
 which to soak most objects previous to their being 
 mounted in balsam, great care must be taken that the 
 objects are not kept too long in it, for if they are, the 
 colour will be nearly taken away, and the object 
 rendered too transparent either for beauty of structure 
 or definition of form. 
 
 73. Objects, when thick, are best mounted in a cell, 
 which may be made of cardboard, thin glass (see 
 Fig. 64, Plate 4), and also thicker glass drilled to form 
 cells (see Pig. 36). If cardboard is used, after it is 
 cut it must be well soaked in turpentine before being 
 used; and in mounting objects in a glass cell, always 
 take care to thoroughly saturate the cell with turpen- 
 tine to get rid of all the air and air-bubbles, after 
 which it must be well cleared from the turpentine by 
 draining. It is best to use the balsam cold in most 
 cases ; but if the object does not contain much air, and 
 it is desirable to mount quickly, hot balsam may be 
 used with advantage, 
 
92 A MANUAL OF 
 
 74 Eor many minute objects, the use of the chloro- 
 form and balsam will be found the best, as most small 
 objects have a great tendency to flow towards the 
 edge of the cover when mounted in the ordinary way, 
 and the cover applied and pressed down. To check 
 this, touch the centre of the glass slip with a small 
 drop of turpentine ; place the object or objects in this, 
 cover with the thin glass, and, whilst slightly pressing 
 the cover, apply at the edges a tube filled with 
 balsam and chloroform (Pig. 66, Plate 4), so that the 
 fluid may run under the cover and flow towards and 
 over the object by its own capillary action. 
 
 75. I have not tried it myself, but many persons 
 prefer using resin dissolved in benzole, and strained so 
 as to clear it from impurities. It is said that it dries 
 much quicker than balsam ; and if the resin could be 
 obtained quite pure, it seems to me to be a good 
 medium for general objects. If the object is to be 
 mounted in this medium, care should be taken that it 
 has been previously soaked in pure benzole ; the slides 
 may be dried in the same way as Canada balsam. 
 
 76. Paper varnish is also often used for mounting 
 many objects; objects mounted in this simply require a 
 previous soaking for a few days in a large quantity of 
 the varnish ; a drop of fresh varnish is then placed in 
 the centre of the slip and the object placed in this, 
 and the cover applied as usual. Nearly the same 
 amount of heat may be used in drying the slide as 
 when balsam is used. 
 
 77. In all these methods of mounting, the object 
 requires a slight pressure to be applied to the thin 
 glass cover. This can be obtained in many ways; 
 for ordinary use I find fine copper wire twisted round 
 
MICROSCOPIC MOUNTING. 93 
 
 the slide the best ; this will give an even and moderate 
 amount of pressure. Thread may also be used, but 
 the wire is preferable. Again, it is recommended by 
 some manipulators to coat the edge of the thin glass 
 cover with thick gum water. As this dries, the super- 
 fluous balsam is squeezed out ; and, lastly, an appa- 
 ratus (see Fig. 29) is used for the same purpose, 
 different degrees of pressure being applied by using 
 elastic bands of different sizes and strength, a full 
 description of which is given in Chapter I., para- 
 graph 26. 
 
94 A MANUAL OF 
 
 CHAPTER, IV. 
 
 THE PREPARATION OF OBJECTS BY THE FLUID AND 
 SEMI-FLUID MEDIUMS. 
 
 78. The fluid method of mounting had, until lately, 
 greatly gone down in the estimation of microscopists 
 as vehicles in which to mount their various specimens, 
 but glycerine, and the more recently used, if not so 
 useful substance, silicate of potass, which appears to 
 be a favourable semi-fluid for certain vegetable objects, 
 when mixed with a small percentage of water, have 
 again caused them to be used. There are many fluids 
 in use, but we will first treat of glycerine, it being 
 the most generally useful, and at the same time the 
 most difficult of all the fluids to mount with, for the 
 various kinds of mediums may generally be sealed 
 with the india-rubber cement ; but glycerine being of 
 a viscid nature and having the property of never 
 drying, makes it very difficult to confine it to a cell 
 without its leaking at the edge. The following 
 twelve objects will show the method of mounting 
 with this and also various other fluids. 
 
 Slide 37. Section of human bone. 
 
 Slide 38. Lung of frog (liana temporaries). 
 
 Slide 39. Gizzard of house cricket (Acheta domes- 
 tica) . 
 
 Slide 40. Tongue of snail (Helix Aspersa). 
 
 Slide 41. Wheat starch (Triticum vulgar e}. 
 
 Slide 42. A Zoophyte (Laomedea gelatinosa). 
 
MICROSCOPIC MOUNTING. 95 
 
 Slide 43. A desmid (Micrasterias denticulata) . 
 
 Slide 44. Conferva glomerata a common species 
 of conferva. 
 
 Slide 45. Section of a green capsule of a moss 
 (Bryum Hornum), showing the columella, &c. 
 
 Slide 46. Cuticle of a fern (Poly podium vulgar e}. 
 
 Slide 47. Proboscis of house fly (Musca domestica). 
 
 Slide 48. Crystals of oxalate of ammonia 
 (Cjj O 3 Amo" 2 ) 
 
 Slide 37. Section of Human Bone. After the sec- 
 tion of bone has been cut and prepared as described 
 in Chapter V., it may be mounted if desired in 
 glycerine, or what is still better, in glycerine and 
 acetic acid (Recipe 74,) a suitable cell having been 
 made for its reception as follows : With a camel's 
 hair brush charged with either gum dammar solution, 
 white cement (Recipe 78), or india-rubber cement 
 (Recipe 5), turn a cell of a diameter suitable for 
 the size of the section of bone. In doing this use 
 the Matthews' turn table (Eig 5, Chapter I., pargraph 
 4) ; and at the same time at least one dozen various 
 size cells for future use. When the cell is quite dry 
 it may be filled with glycerine fluid, and the section 
 of bone placed in it. The section may have 
 been previously tinted with nitrate of silver (see 
 Chapter Y.) if desired ; but in any case it must 
 have been previously placed for a short time in 
 glycerine and alcohol. A thin glass cover must then 
 be allowed to fall gradually, so as to cause a wave 
 of fluid to flow onwards (see Eig 67). The super- 
 fluous glycerine must then be removed with the 
 aid of a damp camel's hair brush, washing this and 
 freeing it from the glycerine until all is removed 
 
96 A MANUAL OF 
 
 from the edge of the cell. A very thin layer of 
 dammar varnish must then he painted round the edge 
 of the cover, care heing taken that a fresh hrush is 
 used, and that the varnish is laid evenly and thinly 
 round the edge, hut sufficient heing put to embrace 
 "both the edge of the thin glass cover and the cell 
 previously made. When quite dry it must again he 
 washed with a damp camel's hair hrush, and the hrush 
 constantly freed from glycerine. When all traces of 
 glycerine have been removed, another thin layer of 
 cement must he applied and allowed to dry ; after 
 which, to make quite sure that all the glycerine has 
 been removed, it must be washed once more. When 
 quite dry after this washing, a layer of gold size must 
 be applied. In this case the Matthews' turn-table 
 (Eig. 5) must be used to cover all the inequalities of 
 the surface made by the previous layers of cement. 
 When dry, it may be finished by applying a thin layer 
 of Berlin black varnish, using the turn-table ; after 
 which the slide may be finished and labelled as usual. 
 
 Slide 38. Lung of Frog (Mana temporaries). If 
 injected with the carmine fluid, it may be mounted in 
 glycerine in the same manner as described for the 
 previous object. Most injections show well when 
 mounted in glycerine, or glycerine and acetic acid, 
 though chloride of zinc will be found useful in many 
 cases. 
 
 Slide 39. Gizzard of House Cricket (Acheta 
 domestica). This object when mounted in glycerine 
 shows well ; but for the sake of an illustration of the 
 process we will mount it in silicate of potass. This, 
 when procured at the shops, is too thick for use; it must 
 therefore be diluted with distilled water until it flows 
 
MICROSCOPIC MOUNTING. 97 
 
 freely which will be when about ^th of water is added 
 to f ths of the silicate. A cell having been made of 
 cement as in Slide 37, the gizzard of cricket, which 
 has been previously dissected, opened, and cleaned, 
 (see Chapter Y.) ; it must then be placed in the centre 
 of the cell and sufficient silicate of potass to fill the 
 cell added ; a thin glass circular cover must then be 
 gradually lowered over the object, (as in Pig. 67) ; 
 when this cover has been placed in position, if any 
 air- bubbles occur, the slide must be transferred to the 
 air-pump, Eig. 30, and the bubbles got rid of in the 
 usual manner. Air-bubbles will be found the chief 
 fault in this medium. When the air-bubbles are all 
 gone, the silicate of potass must be allowed to dry 
 
 FIG. 67. 
 
 gradually ; if, in drying, any space is left between the 
 thin glass cover and the slide, it must be filled up by 
 the addition of more silicate. When quite dry it may 
 be cleaned with water and earners hair brush, and 
 finished by turning a ring of gold size, dry, and repeat 
 with Berlin black, in both cases using the turn-table ; 
 it may then be finished as usual. This object also 
 shows well in balsam, glycerine-jelly, &c. 
 
 Slide 40. Tongue of Snail (Helix aspersa). After 
 the tongue has been dissected from the snail and cleaned 
 (see dissections, Chapter V.), it may be mounted in 
 glycerine, Deane's compound, glycerine- jelly, &c. I 
 
 H 
 
98 A MANUAL OF 
 
 prefer the glycerine- jelly which is as follows ; After the 
 tongue has been, well washed it must be drained of all 
 superfluous water, but not allowed to dry. The gly- 
 cerine-jelly having been rendered liquid by placing the 
 bottle in hot water (Recipe 64), a large drop of it is 
 placed in the centre of a suitable size cell made of 
 cement (see Slide 37) ; this drop must be examined to 
 see that it has no air-bubbles in it, if it has, it-must be 
 placed under the air-pump, Pig. 30, and the bubbles 
 got rid of in the usual manner, or if the student has 
 not obtained an air-pump, a fresh drop of jelly must 
 be taken. When quite free from air-bubbles, the 
 tongue, which must be still moist, should be gently 
 placed in the centre of the drop of jelly, care being 
 taken to avoid making any fresh air- bubbles. A 
 moistened circular thin glass cover must then be ap- 
 plied, dropping it upon the centre of the drop of jelly, 
 and gradually pressing it downwards until all the super- 
 fluous jelly is squeezed but at the edge ; let it set 
 thoroughly, then with the turn-table turn a ring of the 
 white cement (Recipe 78) round the edge of the glass 
 cover so as to hide the edge ; when dry, finish with 
 one or two coats of Berlin black applied with a camel's 
 hair brush in the same manner. Finish as usual. 
 
 Slide 41. Wheat Starch (Tritioum vulgare). After 
 the starch has been separated from the gluten by the 
 usual process of washing (see Starch, Chapter V.), a 
 small quantity may be taken and mounted in a suit- 
 able fluid (Recipe 56) in a shallow cell, proceeding in 
 the same manner as Slide 37 ; only in this case the 
 superfluous fluid may be entirely soaked up by using 
 small strips of blotting paper; when quite dry at 
 the edge it is best to use the india-rubber cement 
 
MICROSCOPIC MOUNTING. 99 
 
 (Recipe 5) for sealing the cell ; after which a layer of 
 the white cement (Recipe 78) must be put on by using 
 the turn-table : finish with Berlin black as usual. 
 
 Slide 4Q. A Zoophyte (Laomedea gelatinosa) This, 
 together with other species of zoophytes, should be 
 killed quickly, so that the tentacles are extended 
 (see Chapter VI). They may be mounted in many 
 ways, in Deane's compound, glycerine- jelly, chloride 
 of calcium, and in fluids (Recipes 48, 56, 58, 76, &c.); 
 but I prefer a fluid of nearly the same density as that 
 in which they live, which I make, by adding to 6 oz. 
 of fresh sea-water a J oz. of proof -spirit, in which six 
 drops of creosote have been dissolved ; in this fluid 
 I always keep a small lump of camphor constantly 
 floating ; a small percentage only dissolves in the 
 sea-water. This fluid will also be found useful in 
 mounting marine algse, &c. The process of mounting 
 the zoophytes varies but little from the method used 
 for other objects in fluid ; a suitable cell, both in size 
 and depth, being chosen. In some cases where the 
 zoophyte is large, a glass cell like those at Pig. 36 
 will be required, in which case great care must be 
 taken that all air bubbles are excluded. All the 
 branches or polypidoms must be neatly placed, and 
 the tentacles of all the polypes being extended where 
 it is possible ; in doing this, use one of the smallest 
 camel's hair brushes fixed in a suitable cedar handle : 
 the cover may then be applied and sealed with any 
 of the proper cements as used for Slides 40, 41, &c., 
 it may then be finished and labelled as usual. 
 
 Slide 43. A Desmid (Micrasterias denticulata) . 
 The process of collecting desmids is described in 
 Chapter VI., and the method of separating them 
 
 H 2 
 
100 A MANUAL OP 
 
 from the mud, &c., at Chapter V. Many fluids have 
 been recommended in which to mount these delicate 
 organisms, the best of which will be found in Recipes 
 79, 76, 58, 56, 12, &c., but I prefer glycerine alone, 
 which is added in a gradual manner so as to prevent 
 the rupture of the primordial utricle : a description of 
 the process is given at Slide 45 ; in all other respects 
 the desmids may be mounted in a shallow cell and 
 sealed with the same cement as described for Slide 37, 
 page 87, the size and depth of the cell being of course 
 much less. Finish as usual. 
 
 Slide 44. Conferva Glomerata a Common species 
 of Conferva. A few threads of this conferva must be 
 taken and mounted in a shallow cell in precisely the 
 same manner as described for the following object in 
 Slide 45 but if desired, it may be mounted in a 
 suitable fluid, Hecipe 76. 
 
 Slide 45. Section of a Green Capsule of a Moss 
 (Bryum hornum), showing the Columella, fyc. A cell 
 having been made by the aid of the turn-table, Pig. 5, 
 of a depth equal to the thickness of the section of the 
 capsule, which section must be made in the manner as 
 described in Chap. V., paragraph 149, the capsule having 
 been previously embedded in the wax, it must then be 
 taken and put in a solution as follows : Mix 4 parts 
 alcohol, 3 parts water, 1 part glycerine ; place this fluid 
 in a bottle or jar having a wide open mouth ; in this, 
 place the object or objects (for it is as well to do more 
 than one, as it saves time and trouble) ; place the 
 jar or bottle in a warm place, so as to allow the alcohol 
 and water to evaporate, leaving the object in the 
 glycerine, which does not evaporate. It is better to 
 keep the jar under a large bell glass whilst the fluids 
 
MICROSCOPIC MOUNTING. 101 
 
 are evaporating, as it keeps them from dust ; but 
 this is not absolutely necessary if the room is not very- 
 dusty. The above plan prevents rupture of the pri- 
 mordial utricle from the action of osmosis, &c. The 
 section of capsule, desmids, &c., may then be trans- 
 ferred to pure glycerine, and mounted in a shallow cell 
 like any other object that is preserved in glycerine. 
 
 Slide 46. Cuticle of a Fern (Poly podium vulgar e). 
 For the method of separating the cuticles of leaves, 
 &c. (see Chaper V.) Cuticles, when thin and filmy, 
 as in this case, show best when mounted in a fluid, 
 Recipes 76, 58, 56; but if thick and leathery are 
 best when mounted in glycerine or balsam, &c. ; if 
 the cuticle is silicious, it is mounted in balsam 01 
 dammar for the polariscope. Both the filmy and 
 leathery cuticles are mounted in a shallow cell, and 
 sealed in the same manner as Slide 37, &c. 
 
 Slide 47. Proboscis of House Fly (Musca domes tica). 
 Eor the method of dissection of the proboscis (see 
 Chapter V.) This object shows well when mounted 
 in glycerine, but previously to this it should be 
 subjected to the same treatment as the section of the 
 capsule of moss, Slide 45 after which it may be 
 mounted in a cement cell of the right depth, glycerine 
 or glycerine- jelly being used. Seal the cell with the 
 dammar varnish, and finish as usual. 
 
 Slide 48. Crystals of Oxalate of Ammonia. 
 (C 2 O 2 Amo" 2 ). Castor oil will be found the best 
 medium in which to mount these crystals, and also 
 nearly all forms that are at all deliquescent. Glyce- 
 rine also answers for some, but it is not to be equally 
 depended upon, for after a short time it often attacks 
 the form of the crystal. The method of mounting in 
 
102 A MANUAL OF 
 
 castor oil is as follows : After the true form of the 
 crystal has been obtained (see Chapter V.), it must be 
 surrounded with a layer of dammar varnish put on 
 with a "brush. This ring or layer of varnish may be 
 of an oval, square, or circular form, but in any case it 
 must be made exactly in the centre of the glass slip, 
 that is, if neatness is any object. When the dammar 
 varnish is nearly dry, sufficient castor oil should be 
 dropped into this shallow cell, and the thin glass cover 
 which should be of the same shape as the cell, applied 
 as shown at Eig. 67. All the superfluous oil should 
 then be cleaned off with either turpentine, benzole, or 
 ether, using a brush in the same manner as described 
 for clearing a cell from superfluous glycerine (see 
 Slide 37) : repeated coats or layers of the india-rubber 
 cement, Recipe 5, or of the dammar varnish, must 
 then be applied ; each layer to be allowed to dry some 
 time before the next is applied. It must then be 
 finished and labelled as usual. 
 
 79. I have described all these objects as mounted 
 on ground edge slips, for if any leakage occurs it will 
 be much easier to remedy it, than if the object had 
 been mounted in a cell, the edges of which had been 
 covered with the usual paper cover (see Fig. 45, 
 plate 1). 
 
 80. Many plans have been recommended for closing 
 cells filled with glycerine. Mr. Suffolk uses a coating 
 of common liquid glue, and when dry, he washes it 
 well to free it from all traces of the glycerine. When 
 the water used in washing dries off, another thin layer 
 of the glue is applied, and washed, and so on for three 
 separate layers. Gold size is then applied with a 
 brush, using the turn-table. It is then finished with a 
 circle of black varnish. 
 
MICROSCOPIC MOUNTING. 103 
 
 81. Glycerine dissolves in water, alcohol, &c. It 
 is also a solvent for many substances, and in testing, 
 Dr. Lionel Beale recommends it strongly for dissolving 
 the various salts used as re-agents. I prefer pure dis- 
 tilled water in this case. N.B. It should never be used 
 in mounting any objects that contain carbonate of 
 lime, as it dissolves that substance. Like fixed oils, 
 it never evaporates or dries up, which property makes 
 it very useful for nearly all purposes requiring only 
 temporary observation ; care, of course, being taken 
 that it is not used for algae, &c., without due care 
 (see Slide 45), or it will rupture the cell- wall. When 
 used for any object that is under temporary ob- 
 servation it is not necessary to seal the cell (see 
 Chapter VII). 
 
 82. Glycerine will be found a very useful medium 
 in which to dissect all objects where the tissues are at 
 all delicate, as it bathes them, and at the same time 
 affords more support, the fluid being of a much 
 greater specific gravity than water. 
 
 When specimens are mounted in glycerine, it is 
 sometimes troublesome to seal the cell in which they 
 are contained ; but if great care is used in washing, 
 this is got over. 
 
 Objects mounted in glycerine generally improve by 
 keeping. 
 
 83. If objects are soaked in the preservative fluid 
 (see Recipe 80) previous to their being mounted in 
 glycerine, "they will be rendered very transparent. 
 
 All objects mounted in Deane's compound, glycerine- 
 jelly, glycerine, Ralph's liquid, and other semi-fluids 
 and fluids, require a great deal of soaking in a large 
 quantity of the liquid that they are to be mounted in. 
 
104 A MANUAL OF 
 
 When they are to be mounted in jelly and other semi- 
 fluids, glycerine is generally the best to use. The 
 object of this continued soaking is to rid the object of 
 air-bubbles, and even then the air-pump (Eig. 30) is 
 often required before they can be entirely got rid of. 
 
 84. When the cell that is used for mounting has 
 been over-filled with the fluid, and, of the two, to 
 over-fill is better than not to use enough, blotting- 
 paper is used to remove the superfluous fluid. 
 
 85. Lamp-black, moist colour, in tube, as sold by 
 artists' colourmen, will be found useful for finishing 
 slides when slightly diluted with water. When dry, 
 it may be varnished over with gold size. 
 
 86. In any case, never lay varnish on thickly when 
 it is used for sealing and finishing cells, &c. 
 
 87. A saturated solution of common salt (chloride 
 of sodium NaC) forms a good preservative fluid for 
 many of the entomostraca, .palates, &c. Sea- water, if 
 camphor has been dissolved in it, will also be found 
 useful for preserving delicate marine plants, zoophytes, 
 &c., as it prevents osmosis (see Slide 42), and with 
 care they may often be transferred to glycerine if 
 required. 
 
 88. A solution of arsenious acid in camphor water 
 is often used for the preservation of specimens, espe- 
 cially animal ; but it is very poisonous, and other 
 solutions do as well (see Hecipe 57). 
 
 89. Syrups will be found useful for preserving 
 tissues, especially vegetable. The remains of seeds, 
 cuticles, &c., taken from jams and preserved and 
 crystallized fruits will be found in a good condition 
 for examination, and will often be found worthy of 
 preservation, especially to public analysts. 
 
MICROSCOPIC MOUNTING. 105 
 
 90. Castor oil is useful in mounting crystals ; also 
 acari, parasitic and other small insects. 
 
 91. Solutions of borax and boracic acid have been 
 found to retard the contractile power of muscle, and 
 will also, no doubt, be found to be good preservative 
 fluids for the preservation of the muscular parts of 
 insects, &c. It is worthy of further trial. 
 
 92. All the preservative fluids may be kept in the 
 collapsible tubes (see Fig. 66, Plate 4) ; but where the 
 fluid contains any corrosive salt, as in the case of 
 Recipes 58, 59, 60, &c., the inside of the tube must 
 be coated with bees' -wax to protect it from the action 
 of the fluid. It may be coated in the following man- 
 ner : Pour melted bees' -wax into it until full, and 
 immediately empty it again ; then place the tube 
 upright on a plate, which place in a hot oven or before 
 the fire to allow the superfluous wax to drain from the 
 tube ; then place it in a cool place. When quite dry, 
 the preservative fluid may be poured into it, and the 
 edge turned up, and closed in the usual manner. 
 
 93. Pollens show best when mounted in an essential 
 oil, such as lemon. In sealing the cell the india- 
 rubber cement (Recipe 5) must be used. 
 
106 A MANUAL OF 
 
 CHAPTER Y. 
 
 A GENERAL SUMMARY OF THE VARIOUS METHODS OF 
 MOUNTING, WITH MANY ADDITIONAL NOTES. 
 
 94. In Chapters II, III, and IV, I have treated of 
 the various methods of mounting microscopic objects, 
 but in this chapter I shall mention the various 
 methods of preparation to render them ready for 
 mounting in any of the before-mentioned mediums. 
 Suffice it to say that all objects should be well 
 examined both dry, balsam, and in fluid. 
 
 95. Acarea (family) or Mites. An example of this 
 class of objects is the cheese mite (Acarm domesticus). 
 The parts of the mouth, &c., sufficient to distinguish 
 the species, are generally made out from crushing the 
 insect between a glass slip and piece of thin glass, 
 but if it is required to mount permanently, greater 
 care must be taken in crushing them, and all extraneous 
 matter separated by solution of potass. Afterwards 
 wash with acetic acid, and mount in glycerine (see 
 Recipe 74), or dry, and mount in balsam or gum 
 dammar. They do not require a cell if mounted in 
 this manner. 
 
 96. Acheta domestica (House cricket). "From this 
 insect many interesting objects can be obtained (see 
 "Gizzards, Elytra, &c."). 
 
 97. Adulterations (see Chapter VII.) 
 
 98. AlgcB. After having been well washed in fresh 
 
MICROSCOPIC MOUNTING. 107 
 
 water, or if marine, in sea water and then fresh water, 
 they may be mounted in Deane's compound (Recipe 
 75), or in glycerine-jelly (Recipe 64), or they may 
 be mounted in a cell with a suitable fluid (such as 
 Recipe 58, or Recipe 76) ; if mounted in glycerine, 
 care should be taken to place the algae in fresh dis- 
 tilled water, and gradually add the glycerine. This is 
 best done by putting the specimen in a watch glass, 
 and adding about every hour, two or three drops of 
 pure glycerine, until the proper consistency is gained, 
 or do as recommended, see Slide 45. By these plans 
 all rupture of the cell walls will be prevented. For the 
 method of mounting in glycerine, see Chapter IV., 
 under Slide 37. 
 
 99. Anguillula. Anguillula glutinis is one of the 
 most common species of this genus. They have been 
 popularly called " eels in paste;" and as it is interest- 
 ing to observe their movements, I give the method of 
 obtaining them. Make a moderately thick paste with 
 flour and water, stir and beat up daily with a spoon to 
 prevent any growth of moulds, when, if the weather is 
 moderately warm, the young entozoa will be found, 
 sometimes in large quantities. To observe them, place 
 a small piece of paste containing them in a drop of 
 water in an ordinary animalcules box, or between the 
 two cells of the gas cell (Figs. 9 and 10, Chapter I, 
 paragraph 7). These animals may be kept for years 
 if a little fresh paste is added occasionally. 
 
 100. Anoplura. An order of insects, parasitic, upon 
 birds and animals, generally known as lice. These 
 insects may be treated in a similar manner to the acari 
 or mites, especially if they are of a small species ; if 
 larger, as in the case of the parasite on the pig, human 
 
108 A MANUAL OF 
 
 &c., it is better to treat them with potass as described 
 for small insects (see Chapter III., under Slide 25), 
 and mount in balsam or dammar, or they may be 
 washed in acetic acid, and mounted in glycerine. 
 
 101. Antenncs of Insects. These organs require but 
 little dissection. It generally is sufficient to cut them 
 off from the head of the insect with a pair of sharp- 
 pointed scissors, and if thick, remove them, to be 
 softened in the potass, washed, pressed, dry, and 
 mounted in balsam in the ordinary manner ; if not 
 thick enough to require this, they must be soaked for 
 a short time in turpentine, which will render them 
 transparent enough to be observed, or in some cases 
 they may be mounted dry transparent, as, for instance, 
 the antennae of the common gnat. Some of the 
 antennae of the larger beetles only show well when 
 mounted in a dry opaque cell. Many of the small 
 antennae show well when put up in a cell in a suitable 
 fluid (Recipes 3, 12, 56, 59, &c.) 
 
 102. Anther. This part of the stamen of flowers 
 contains the pollen. The case or anther often has a 
 very beautiful epidermis, which may be separated from 
 the other tissues by the action of dilute nitric acid, as 
 mentioned in the treatment for cuticles ; but the 
 epidermis being very delicate, greater care must be 
 taken than with any ordinary cuticle. The following 
 flowers contain the most beautiful forms: Poets' 
 Narcissus (Narcissus poeticus) ; white poplar (Poputus 
 alba) ; thorn apple (Datura stramonium) ; wall-flower 
 ( Cheirantlms cheiri) ; Henbane (Hyoscyamus orien- 
 talis ; Iris jlorentina) ; rocket (Bunlas orientalis)\ 
 London pride (Saxifraga ambrosa) ; yellow water lily 
 (Nuphar lutea) ; bryony (Bryonia dioica) ; privet 
 
MICROSCOPIC MOUNTING. 109 
 
 (Ligustrum vulgare, Calceolaria, Anemone, Veronica 
 perfoliata, Tropceolum majus) ; (Primula sinensis) ; 
 forget-me-not (Hyosotis palmtris, Adonis vernalis, 
 Magnolia}-, daisy (Bellis perennis) ; dandelion (Leon- 
 todon), &c. 
 
 103. AnlJieridia. These interesting bodies, which 
 answer to the anthers of the flowering plants, that is, 
 they contain the reproductive bodies called sperma- 
 tozoids, &c., which act in a similar matter to pollen, 
 only much more active, are well worthy of study. 
 Mosses and lichens being the best and easiest plants 
 for this purpose, they are best mounted in fluid (see 
 Eecipes 56, 58, 76). 
 
 104. The Antlia, or as it is commonly called, the pro- 
 boscis of moths and butterflies, is an interesting object 
 when properly mounted. After it is divided from the 
 head of the insect, it must be placed for one or two 
 hours in a weak solution of potass ; if kept in this 
 fluid longer than two hours it will get too soft to 
 mount properly ; if a small and delicate one, it must 
 not be kept longer than one hour ; press gently 
 between two glass slips to flatten it ; then well wash 
 in acetic acid, and then water, after which it may be 
 mounted in glycerine or dried under pressure (use 
 apparatus, Pig. 29), and mounted in balsam or dammar 
 as usual. 
 
 105. Aphidce. These insects being of a very delicate 
 structure, require but little preparation. I find the 
 best method is to press them between glazed writing 
 paper until nearly dry ; then transfer them to water, 
 after which they may be dried under pressure and 
 mounted in balsam, or transferred from the water to a 
 suitable fluid (see Recipes 56, 14, &c.), and mounted 
 
110 A MANUAL OF 
 
 in a shallow cement cell. It will be found that 
 glycerine renders them too transparent. 
 
 108. Arachnida. This class of animals contain the 
 spiders, scorpions, &c., and many interesting objects 
 can be obtained from it ; the mandibles of spiders, 
 spinning organs, toothed feet, and the poison bag or 
 sac. The part of the head containing the mandibles 
 requires but little preparation. Soak in potass for a 
 short time to soften them ; well wash, dry under 
 pressure, and mount in balsam as usual. The spin- 
 ning organs must be taken from the body of the 
 spider ; they will be known by appearing like three 
 small cone-shaped bodies at the end of the abdomen ; 
 they must be cut away with a pair of sharp scissors, 
 cleaned with potass, and then warm water, dried under 
 pressure, and mounted in balsam ; or they may be 
 mounted in glycerine in a shallow cell, so as to show 
 them in their natural position. The feet of the spider 
 only require soaking in the potass ; put under pressure, 
 then well wash and mount in glycerine ; or dry and 
 mount in balsam. To find and show the poison bag 
 well, one of the mandibles must be placed in water, 
 and allowed to remain for about a fortnight ; it will 
 then be found slightly decayed, and if one of the 
 mandibles is separated at the second joint from the 
 other parts, it will draw out with it the poison bag or 
 sac, and if its course is traced it will be found to 
 terminate in a minute orifice near the tip of the 
 mandible. After being well cleaned it may be 
 mounted in glycerine, glycerine- jelly, or dried and 
 mounted in balsam or dammar. 
 
 107. Apothecium. This name is given to the open 
 cup-shaped bodies containing the spores, &c., of 
 
MICROSCOPIC MOUNTING. Ill 
 
 lichens, a section of which must he taken to give a 
 correct idea of their structure. These sections may 
 he mounted in Deane's compound, glycerine- jelly, or 
 in a suitahle fluid (Recipes 56, 58, 76, &c.), or dried 
 under pressure, and mounted in halsam as usual. 
 When the entire cup or apothecia is taken, it only 
 requires to he mounted in a dry opaque cell. The 
 sections must he made with a fine scalpel. 
 
 108. Archegonium. This is the rudimentary organ 
 representing the ovule of mosses, ferns, &c. They 
 show hest when mounted in Deane's compound, or a 
 suitahle fluid (Recipes 56, 58, &c.) 
 
 109. Blight. The examination of the various 
 species of this class of micro-fungi will he found 
 interesting. Some of the hest forms are : Hop hlight 
 (Sphcerotheca castagnei) ; maple hlight ( Uncinula 
 biGornis) ; guelder rose hlight (Microsphceria penicil- 
 lata) ; hazel hlight (Phyllactinia guttata) ; rose hlight 
 Splicer 'otheca pannosa, &c.) To show the conceptacles, 
 the hest plan is to mount a small piece of the leaf 
 containing the hlight in a dry opaque cell. The 
 wooden slides (see Pig. 58, Plate 3) answer well for 
 this purpose ; or a very small piece of the leaf may 
 he mounted for the use of the paraholic reflector (see 
 Pig. 56, Plate 2 ; also description, Chapter II., under 
 Slide 13). The conceptacles and spores may also he 
 mounted as transparent ohjects, either in Deane's com- 
 pound or glycerine-jelly, in which case they must he 
 previously soaked in a small drop of water placed in 
 the exact centre of a glass slip ; or they may he 
 mounted in glycerine or halsam; hut however mounted, 
 a slight cell of india-ruhher cement (Recipe 5) must 
 be used to prevent the conceptacles heing crushed. 
 
112 A MANUAL OF 
 
 110. Blood. The best method of mounting so as to 
 show the corpuscles of the blood (Kg. 68) well is to 
 ^ a ^ e a ^- r P ^ f resn blood and spread it 
 evenly, and as thin a layer as possible, 
 over the centre of a glass slip, and 
 allow it to dry; then mount in the 
 C ^ r y ^ rans P aren t method ; or use the 
 vapour of a two per cent, solution of 
 osmic acid; then apply one drop of 
 acetate of potass, and cover with thin glass as usual. 
 This is recommended by Professor Mac Schultze. By 
 this plan the corpuscles are but little altered. In 
 spreading them thinly and evenly, it will be as well 
 to use a small piece of thin glass moved over the 
 centre of the slip with a circular motion. If it is 
 only desired to observe the blood whilst fresh, a piece 
 of thin glass must be placed on a glass slip, and a drop 
 of fresh blood allowed to flow under it. By capillary 
 action, the corpuscles will then be found to be evenly 
 distributed, and their size, colour, and shape may be 
 observed. If it is desired to obtain and observe the 
 corpuscles after they have been long dried upon linen, 
 cotton, or any other material, this should be soaked in 
 a saturated solution of corrosive sublimate (HgCl 3 , 
 See Recipe 10). The shape of the corpuscles will then 
 be nearly restored to their normal condition, and may 
 be separated from the material with the aid of a small 
 camel's hair brush. (For blood Crystals, see para- 
 graph 117). 
 
 111. Bone. To make sections of bone, the piece 
 that is required to be cut must be placed in the hold- 
 ing-screw, Pig. 6, and tightly fixed by the aid of the 
 screws, and a section cut with the small saw, Pig. 22, 
 
MICROSCOPIC MOUNTING. 113 
 
 This section must be cut as thin as possible with the 
 saw ; one side of the section must then be ground with 
 various files of different degrees of fineness ; then with 
 water on an Arkansas stone and polished with putty- 
 powder on a leather strop ; this polished side must 
 then be cemented to a piece of glass with Canada 
 balsam (see Recipe 69), and the section ground until 
 thin enough ; finish and polish as with the first side ; 
 the section may then be removed from the glass, clean, 
 and mount in a dry transparent cell. If it is re- 
 quired to mount the section in Canada balsam, it need 
 not be ground on the stone nor polished. In fixing the 
 section to the glass, care must be taken before grinding, 
 that there are no air-bubbles between the section 
 and the glass, for if so, it will not grind evenly and 
 flat. If the section is large enough, it is better to 
 grind it between a piece of velvet- cork and the file, in 
 preference to cementing it to the glass. The action of 
 hydrochloric acid (HC1) and also the solution of potass 
 on the sections of bone should be studied ; the hydro- 
 chloric acid will dissolve the lime contained in the 
 bone and leave the animal matter. The potass will 
 do just the opposite leave the lime and dissolve the 
 animal substances. Sections of bone may be readily 
 cut after it has been treated with the hydrochloric 
 acid ; these sections show well when mounted in bal- 
 sam and examined under polarised light. Isinglass 
 glue is sometimes recommended for fixing the sections 
 to the glass before grinding, as it does not fill up the 
 lacunae so much as the balsam, and also requires no 
 heat. Fossil bones are ground and finished in the 
 same manner as ordinary bone, only greater amount 
 of care must be taken in the grinding, as they are 
 
 i 
 
A MANUAL OF 
 
 generally very brittle. If large, and sections are re- 
 quired to be cut and ground, this is generally done 
 with the machine used for cutting and grinding rock 
 sections, see Pig. 38. 
 
 112. Brands. These form another large and in- 
 teresting part of the micro-fungi; they may be mounted 
 in the same manner as the blights, but to show the 
 spores, &c., well, they must be soaked in turpentine 
 and mounted in balsam or dammar. Some of the most 
 interesting forms are : the rose brand (Aregma mucro- 
 natimi) ; bramble brand (Aregma bulbosnm) ; meadow 
 sweet brand ( Triphragmi/am nlmarice) ; anemone brand 
 (Puccinia anemones) ; composite brand (Puccinia com- 
 positarum} ; ground ivy brand (Puccinia glechomatis) ; 
 willow herb brand (Puccinia pulverulent 'a) ; mint brand 
 (Puccinia menthce). 
 
 113. Chalk. Carbonate of lAme (CoCao"). The 
 best method of preparation to get the the foraminifera 
 clean is to take a small piece of chalk and scrape it 
 fine, or, what is better, a small quantity of the natural 
 powder found at the base of chalk cliffs ; put this into 
 an 8-oz. phial and fill with water, which remove with 
 glass syphon. Keep on adding fresh water as long as 
 it comes away of a milky tint, the deposit will then be 
 found to consist of the foraminifera remains of sponge, 
 spiculse, &c. To mount the foraminifera, a small 
 quantity should be soaked in turpentine for a short 
 time, and then mounted in balsam as usual. If any 
 air-bubbles occur, they will disappear in the course 
 of a few days. Many persons prefer to reduce the 
 chalk to a powder previous to washing, by rubbing 
 it with a tooth-brush or any other moderately hard 
 brush. 
 
MICROSCOPIC MOUNTING. 115 
 
 114. Characea are good plants to observe the circu- 
 lation of the chlorophyll ; young shoots are the best 
 for this purpose, as they contain less carbonate of lime, 
 which often obscures the view. 
 
 115. Chicory. This substance is much used for the 
 adulteration of coffee (see Chapter VII.). 
 
 116. Circulation. In studying the circulation in 
 any animal, the first essential is, that it should be kept 
 on the stage of the microscope. This has generally 
 been attempted by mechanical restraint, as in the 
 case of the frog. " Sometimes chloroform is used, but 
 the subcutaneous injection of the hydrate of chloral 
 will be found to answer much better. A solution of 
 four grains to the drachm is the best. As many 
 minims should be injected into the frog as it is drachms 
 in weight. The injection is made under the skin of 
 the back with a morphia syringe. The web of the 
 foot may then be stretched over the frog plate in the 
 usual manner. When the tongue is used for observing 
 the circulation, it is withdrawn from the mouth by 
 means of horn forceps, and stretched over a large 
 perforated cork. It is apt to become dry, when it must 
 be moistened with water, or what is better of water 
 100 parts, salt 1, and albumen from egg, 10 parts." 
 The circulation of blood is also well seen in young 
 trout, wing and membrane of common bat, tadpoles, 
 &c. The apparatus used for tadpoles is seen at Eig 39. 
 
 117. Coleoptera (Beetles). The most interesting 
 parts of these insects are the gastric teeth and gizzards, 
 and the eyes, elytra, &c. If small, the whole insect is 
 often mounted in a dry opaque cell, as in the case of a 
 small green weevil, so-called British diamond beetle 
 (Polydrosm pterygonialis). Slide 22, Chapter II. 
 
 i 2 
 
116 A MANUAL OF 
 
 118. Collomia Seed. The examination of the spiral 
 fibres of this seed form an exceedingly interesting 
 object under a low power. A very small slice must 
 be cut from the testa or outer coat of the seed, and 
 placed in a drop of water, when the fibres will 
 gradually uncoil. It may then be mounted in a 
 shallow cell in a suitable fluid (see Recipes 56, 76, 
 
 &c.). 
 
 119. Confervoidece are best mounted in a shallow cell 
 with a suitable fluid (either Recipes 78, 76) ; or if 
 mounted in glycerine it must be added to the water 
 very gradually (see algae). 
 
 120. Corallina. This genus of algse are found nearly 
 everywhere on the rocks between the high and low 
 water marks. They must be well washed in fresh 
 water, and then dried and mounted in a dry opaque 
 cell; or, if their structure is desired to be observed, 
 dissolve the carbonate of lime by the action of hydro- 
 chloric or acetic acid. They must then be washed and 
 mounted in a cell with a suitable fluid (Recipes 12, 56, 
 58, &c.), or in glycerine (Recipe 74), or they may be 
 dried and mounted in balsam ; but fluid will be found 
 the best to show the tetraspores. 
 
 121. Corns. Sections of these excrescences show 
 well, especially under the polariscope. To render the 
 epidermic scales distinct, the sections must be treated 
 with acetic acid or the solution of potass. 
 
 122. Cork. Very thin sections show the cellular 
 tissue well under a high power. Loaded corks are 
 also used for dissections. A piece of velvet cork, about 
 two inches square and half inch thick, is placed on a 
 piece of sheet lead, three inches square, the sides of 
 which are cut and folded over the cork; the edges 
 
MICROSCOPIC MOUNTING. 
 
 may be made smooth with a file. The insect is then 
 fixed to the cork with pins, and is ready for dissection 
 (see Dissections, and also Chapter I., paragraph 20. 
 
 123. Crystals. The plan recommended hy M. 
 Preyer for producing crystals from blood is as follows : 
 The blood is received into a cup, allowed to coagu- 
 late, and placed in a cool room for twenty-four hours. 
 The serum is then poured off, and a gentle current 
 of cold distilled water passed over the finely divided 
 clot placed upon a filter until the filtrate gives 
 scarcely any precipitate with bichloride of mercury. 
 A current of warm water (30-40 Cent.) is now 
 poured on the clot, and the filtrate received in a 
 large cylinder standing in ice. A small quantity is 
 taken, and alcohol added drop by drop till a precipi- 
 tate falls. The mixture still kept in ice, will, after the 
 lapse of a few hours, deposit a rich crop of crystals. 
 The form of these crystals differ in various animals, 
 but are all reducible to the rhombic and hexagonal 
 forms. The best animals for experiment are the 
 guinea-pig, cat, mole, dog, squirrel, sheep, horse, pig, 
 ox, goose, sparrow, frog, bream, perch, pike, &c. 
 The crystals are not generally soluble in water, 
 alcohol, &c., but are perfectly so in alkalies. They may 
 be mounted dry, or better, in castor-oil or glycerine. 
 
 Most crystals form best when a less than saturated 
 solution of a salt is used, the solution being allowed 
 to evaporate spontaneously ; but exceptions may be 
 taken to this rule, especially in the case of delique- 
 scent crystals, which must be obtained by the evapo- 
 ration of their solutions by the aid of gentle heat, 
 after which they are mounted in castor-oil. 
 
 A good plan for the formation of fine specimens of 
 
118 A MANUAL Of 
 
 crystals, especially the salts of lime (calcium), is to 
 mix a small quantity of each salt, which is to react 
 upon each other, in ahout a teaspoonful of gum water, 
 and then gradually mix the two fluids, when perfect 
 crystals will be obtained. The reaction may thus be 
 illustrated : Sulphate of zinc about eighty drops of 
 a saturated solution of this salt is mixed in a teaspoon- 
 ful of gum water, and about eighty drops of chloride 
 of calcium put into another ten spoonful of gum water ; 
 gradually mix the two, when in a short time, fine 
 needle-like and radiating clusters of sulphate of lime 
 (see Pig. 131, plate 11) will be found, the lime having 
 a greater chemical affinity for the sulpho- oxygen 
 compound (SO 3 ) of the sulphate of zinc than the zinc 
 itself has. The reaction is thus : 
 
 CaCl 3 +S0 2 Zno' / =S0 3 Cao // +ZnCl 3 . 
 
 Another and perhaps better plan is to place small 
 quantities of the undissolved crystals used at a short 
 distance from each other in the same vessel, or else 
 separated by a membrane. The liquid used as the 
 solvent can still be gum water, glycerine, albumen, 
 solution of gelatine, or a mixture of these substances. 
 Calcareous salts form best by this process. The follow- 
 ing are a few of the best salts : 
 
 o 
 
 Chloride of Calcium, 
 Nitrate of Calcium, 
 Acetate of Calcium, 
 Chloride of Magnesium, 
 Sulphate of Magnesium, 
 and for the reactions 
 
 Carbonate of Sodium, 
 
MICROSCOPIC MOUNTING. 119 
 
 Carbonate of Potassium, 
 Phosphate of Sodium, 
 Phosphate of Ammonia, &c. 
 
 A great resemblance to organic forms are often 
 obtained when the solvent used is albumen, or albumen 
 and gelatine mixed, and if carmine is iised to colour 
 the fluid, the crystals, &c., obtained are generally of 
 a beautiful tint.* Other colouring matter may be used, 
 especially if of an organic nature such as logwood, 
 saffron, &c. I also find, even in an ordinary way, 
 that when a strong solution of gelatine is added to the 
 solution of the salt that is to be evaporated, that better 
 and more perfect crystals are formed, especially if 
 these are to be used for the polariscope. Gum water 
 also answers well, especially for salicine, chlorate of 
 potass, &c. When crystals of any of the salts are 
 wanted for typical slides in micro-chemical analysis, 
 water only should be used as the solvent. Then 
 evaporate gradually. 
 
 Santonine, and many other salts, may be obtained 
 from the evaporation of their solution in chloroform. 
 Alcohol may also often be used. 
 
 The following salts are some of the most interesting; 
 Salicine, pyro-gallic acid, citric acid, tartaric acid, 
 chlorate of potash, sulphate of magnesia, sulphate of 
 iron, sulphate of copper and magnesia, aloine, platino, 
 cyanide of magnesium, acetate of manganese, boracic 
 acid, chloride of palladium, iodide of quinine, uric 
 acid, urate of sodium, oxalate of soda, &c. (see also 
 plate 11). 
 
 * See a paper on this subject by the author in the *' Transactions of the 
 Maidstone and Mid-Kent Natural History Society for 1870." Also in the 
 Journal of the Society of Microscopists i.e. "Lens" published at Chicago, 
 United States, America. 
 
120 A MANUAL OF 
 
 124. Culex. The commonest insect of this genus 
 is the common gnat ( Culex pipiens) . The proboscis of 
 the female is the part most generally mounted ; it only 
 requires to he dried between writing-paper, after which 
 it may he mounted in balsam or dammar ; it may also 
 be mounted in a cell with glycerine without being 
 previously dried. 
 
 125. Cuticle of Plants. When well prepared, the 
 various cuticles of plants will make an interesting and 
 instructive series of slides, They may be obtained 
 from the leaf by prolonged maceration in pure water ; 
 but the better plan is to separate them from the leaf 
 by the aid of nitric acid and water, the acid being 
 diluted more or less according to the texture of the 
 leaf. If fleshy, more water ; if thick and leathery, or 
 silicious, nearly or quite, pure acid must be used. The 
 leaves are boiled in a test-tube with the nitric acid and 
 water until both the upper and under cuticle seem to 
 separate ; the piece of leaf is then transferred to a 
 vessel of pure water a white evaporating dish or one 
 of Liebig's essence of meat pots is the best to use- 
 well wash with water to free it from the acid ; but if 
 the cuticle is very delicate, it may be transferred to a 
 glass slip at once. Let the cuticle lay on the slip with 
 the inner side upwards, then with a cam el's -hair brush 
 and water, wash away all extraneous matter, leaving 
 the cuticle clean. Now place it in a watch-glass full 
 of alcohol until ready to mount, which may be in fluid 
 or balsam, according to the nature of the object. If 
 silicious, and for polarised light, in balsam or dammar 
 (see under slide 30) ; if leathery, in glycerine (see under 
 slide 45); if delicate, in a proper preservative fluid. 
 When the cuticle is silicious, after it has been separted 
 
MICROSCOPIC MOUNTING. 121 
 
 by using pure acid, it must not be allowed to dry en- 
 tirely, or it will cause great trouble to mount it well ; 
 it must therefore be quickly transferred, wbilst still 
 moist, to alcohol, then to benzole, and turpentine; 
 finish by mounting in balsam or dammar (see Chapter 
 III., under slide 30). A solution of chlorate of potass 
 and nitric acid, equal parts,* is also often used for 
 separating ordinary cuticles not being silicious ; they 
 are boiled in the fluid in exactly the same manner. 
 Cuticles of ferns make good slides, but, in fact, the 
 student should examine all the leaves he comes across 
 he will find it good practice. 
 
 126. Desmidlacece. Desmids, whilst fresh, are best 
 cleaned from the surrounding matter by the aid of 
 light. The gathering is put into a white saucer, with 
 a small quantity of pond water. If the saucer is then 
 placed in a strong light, say in a window sill, the 
 desmids gradually collect on the side nearest the 
 light, when they may be transferred to pure water by 
 the aid of a camel's hair brush. When they are thus 
 obtained free from mud, &c., it is as well to transfer 
 them to a suitable keeping fluid, as recommended, 
 under Slide 43. There are many other ways of clean- 
 ing them, but space will not permit of any but the 
 best plan, either for these or other objects, 
 
 127. Diatomacece. The first thing to notice when 
 about to clean either a gathering of diatoms, or a 
 sample of guano, is to test the average amount con- 
 tained, and whether the species are common or not. 
 This is best done by burning a small quantity of the 
 matter containing them on a piece of platinum foil, 
 using the triangle (Fig. 20). Burn until they are 
 
 * N.B. Use caution in mixing. 
 
122 A MANUAL OF 
 
 white, then examine under the microscope, and if 
 good, and in sufficient quantity for the trouble, first 
 noticing if the diatoms are delicate ; if so, use nitric 
 acid only ; hut if not, and most species will hear this 
 treatment, proceed thus : Boil in sulphuric acid, using 
 an open evaporating dish, until the organic matter 
 turns a dark colour, which will he in about one 
 minute, then gradually add, drop by drop, a saturated 
 solution of chlorate of potass, taking great care only 
 to drop it, or it will cause an explosion. The use of 
 the chlorate is to bleach, and it may sometimes be left 
 out ; then throw the entire mass into about twenty or 
 thirty times its own bulk of water, wash well, and 
 decant the dirty water off, using a glass syphon. 
 Then boil the deposit, which is left in nitric acid, for 
 a short time ; well wash, and store in alcohol or dis- 
 tilled water. When a quantity is done, and there are 
 many species of diatoms, then use the apparatus 
 (Eig. 24) ; or advantage may be takan of their 
 different specific gravity when sinking in a conical 
 glass vessel, collect them as they sink with a pipette, 
 from half minute to nearly ten minutes, according to 
 their gravity. 
 
 Many persons prefer to destroy the organic matter 
 by burning them on the platinum foil. When the 
 silicious valve only is left. Then mount as usual. 
 
 They may be freed from algae by using nitric acid 
 1 part, water 20 ; then strain through muslin. 
 
 When collecting large quantities of diatoms, filter 
 the water containing them through cotton wool, then 
 dissolve the wool in sulphuric acid, well wash with 
 distilled water, allow them to settle at the bottom of 
 the glass vessel that has been used for the process, 
 
MICROSCOPIC MOUNTING. 123 
 
 pour off the greater part of the water, and allow the 
 rest to evaporate by the aid of heat. 
 
 In mounting diatoms, always take care that the 
 frustules do not overlap each other, so as to interfere 
 with the view of them. Mount diatoms dry, if 
 small; if larger and coarser, then use balsam; and 
 when the high powers of the microsope are to be 
 used, fix them on the thin glass cover by the evapora- 
 tion of the fluid containing them. 
 
 A very good plan, and perhaps the best, if only one 
 or two good slides are wantod, is to place a small drop 
 of the deposit on a glass slip, and to pick out the 
 diatoms one by one, using the thread of glass (see 
 tools, page 2) until they are collected in sufficient 
 quantity, then mount as usual ; but when diatoms are 
 suspended in a large quantity of water, use a glass 
 tube covered at one end with filtering paper, and over 
 this, muslin tied round the tube with thread. When 
 sufficient quantity has collected on the paper, as the 
 water passes through, cut the paper and collect with 
 a camel's hair brush. Diatoms should show various 
 positions to exhibit structure ; this is best done by 
 mounting in hard balsam, then grind the surface, 
 slightly cover with fluid balsam, and mount with thin 
 glass cover as usual. 
 
 128. Dissections. Of this subject also only a slight 
 sketch, as space will not permit of more. Eyes of 
 insects are extremely simple ; they only require to be 
 taken from the head in the manner shown at A (Eig, 70, 
 Plate 5). Eig. 69 of the same plate represents the 
 head of the house-fly (slightly magnified), with the 
 eyes in their natural position. After being cut from 
 the head they are soaked for a short time in liquor 
 
124 A MANUAL OF 
 
 potass, which frees them from blood and extraneous 
 matter. "When mounted dry, the facets show well, 
 as in A (Pig 71). The proboscis or trunk of the house- 
 fly may also be taken to exhibit the method of prepa- 
 ration of the various tongues. The insect is squeezed, 
 when the proboscis will immediately protrude from 
 the head ; let it lie on a slip of glass, and let a thin 
 glass cover fall gently on to it (see B, Fig. 72, Plate 5). 
 It must then be cut off, and allowed to dry in this 
 position, both of the glasses having been previously 
 slightly greased to prevent its sticking. Mount in 
 balsam in the usual manner, c, Pig. 73, represents 
 the tongue of house-cricket that has been so treated. 
 Gizzards of beetles form an interesting class of objects. 
 The dissection of the common house-cricket will explain 
 the method of dissection (c, Pig. 74, Plate 5), house- 
 cricket slightly over natural size, c, Pig. 75, the same 
 insect having the third pair of legs cut off, and half 
 of the second pair, the abdomen cut up, and the folds 
 kept back with two dissecting pins (see drawing). 
 The gizzard will then be found at the upper part 
 of the abdomen (see same drawing.) c, Pig. 76, 
 represents the entire alimentary system head, food- 
 sac, and gizzard. The position of the gizzard varies 
 but slightly in any of the beetles, always being below 
 the larger food- sac. The gizzard is separated from the 
 other parts and cut open with the fine-pointed scissors, 
 soaked in the potass, which will soon free it from 
 extraneous matter, then well wash, and mount as 
 described at Slide 39. Spiracles of insects are gene- 
 rally seen on each side of the abdomen, and also on 
 both side of the larva of moths, butterflies, &c. 
 D, Pig. 77, Plate 6, represents the magnified ap- 
 
A 
 
 73 
 
MICROSCOPIC MOUNTING. 125 
 
 pearance of the spiracle of the greater water beetle 
 \Dytiscus mar g walls). D, Fig. 78, shows the spiracles 
 as they appear when the elytra or wing case is taken 
 off, the letters s s pointing t ) them. D, Pig. 79, is the 
 perfect insect. The spiracles are cut from the body 
 witl. the fine-pointed scissors, washed with potass, 
 then pure water, and mounted generally in balsam, 
 though sometimes in fluid glycerine is good. The 
 spiracles of flies are on either side of the thorax. E, 
 Fig. 80, shows the larva of the red admiral butter- 
 fly (Vanessa atalanta} as mounted. To show the 
 position of the tracheae in relation to the spiracles, 
 T T points to the tracheae and s s to the spiracles. E, 
 Fig. 81, are a mass of the air tubes or tracheae which 
 have just been taken from a spiracle, these are magni- 
 fied 100 diameters. F, Fig. 82, is the spiracle of blow- 
 fly. The tracheae are easily found and separated, 
 when they must be well washed, and then mounted in 
 fluid. (Recipes 10 and 74 will be found useful). 
 When making dissections, it will be found useful to 
 imbed the insect in wet plaster of Paris ; let it set, 
 always make dissections under water. G, Pig. 83, 
 Plate 6, is a rough sketch of periwinkle, G, Fig. 84, 
 the mollusc, after being taken out of the shell ; and 
 at G, Fig. 85, the palate or tongue is shown proceeding 
 from the top of the head in a spiral manner. It is so 
 drawn to attract the notice of the student to its 
 position, like a coiled spring pointed to by the letter T, 
 in G, Pig. 84. The position of the tongue cannot be 
 mistaken, it is just above the head, and the coil shows 
 through the skin. Other palates are dissected 
 differently, but the general method is the same ; a 
 good plan for the very small mollusca is to boil them 
 
126 
 
 A MANUAL OF 
 
 in liquor potass, when the bodies are entirely dissolved, 
 leaving the palates intact limpets, whelks, and gar- 
 den snails, will be the best to begin with. 
 
 129. Ducts. Scalariform tissue, and most vegetable 
 ducts are mounted in a suitable fluid, like Recipes 76, 
 58, &c. 
 
 130. Dust (see Pig. 86), when taken from most 
 
 rooms will be found to 
 consist of traces of carbon, 
 soot, fibres such as wool 
 and cotton, starch, &c. 
 The dust of the work- 
 room where the student 
 
 i**^ llftft* t &** ^V ^ v * S} s ^ ou ^ ^ e examined, as 
 ^[^%^tra<ltf ^yf^faifi advised in paragraph 59. 
 UT mm MH?a A useful little piece of 
 
 apparatus to keep objects 
 from dust is made by 
 cementing a small knob, made either of cork or wood, 
 .^yO=^. on to a watch glass sealing-wax may 
 be used as a cement. The drawing will 
 s * i '^^^^ illustrate the idea. 
 
 Ft^Stict, \\. Echinus Spines. Transverse 
 sections of these are cut through and ground down 
 in exactly the same manner as sections of bones and 
 teeth (which see) ; only greater care must be taken 
 in fixing them to the glass before grinding, and also 
 care in the grinding itself, so as not to break them. 
 
 132. Eggs of insects are mounted both dry and in 
 fluid. In the former case, the young embryos must 
 be killed by plunging them into acetic acid, and 
 then allow them to dry; or the eggs may be kept in 
 spirit, and when wanted, allow them to dry for three 
 
 FIG. 8G. 
 
MICROSCOPIC MOUNTING. 127 
 
 or four days before mounting ; they will then shrivel 
 up, but may be restored to their original form by 
 placing them under the air-pump (Pig. 30) for a few 
 hours, constantly exhausting the air. If in fluid, try 
 Recipes 10, 12, 56, 58, 74. 
 
 133. Entozoa are generally examined under the 
 compressorium (see Pig. 37), and glycerine will 
 answer well for their preservation. 
 
 134. Feathers of birds generally mounted in dry 
 opaque cells, though for structure sometimes in balsam. 
 
 135. Foraminifera. Por separating foraminifera 
 from sand, some persons recommend thoroughly dry- 
 ing, and then throw the sand into water, when the 
 minute shells which contain air will swim, and the sand 
 sink ; see also specific gravity apparatus as figured in 
 the appendix. Others recommend picking them out 
 one by one, when the sand is placed on black paper, or 
 use the finder (fig. 25) ; but the best plan, and one that I 
 believe is entirely my own, is to separate them by a 
 chemical process as follows: Boil the sand in a test- 
 tube containing only carbonate of potass or soda, 
 which must be previously fused by the action of heat; 
 throw the sand in, and boil until all the carbonic acid 
 gas has passed off, leaving in the test tube silicate of 
 potass or soda, which must be dissolved in hot water ; 
 if any sand is still left, repeat the process. By this 
 plan the foraminifera are freed from animal matter as 
 well as the sand. "When it is desired to separate the 
 foraminifera from sea soundings, which often contain 
 tallow, they must be cleaned by using benzole, care 
 being taken not to bring it near a light, as it is 
 inflammable. When the benzole comes away quite 
 pure, which may be known by its not leaving any 
 
128 A MANUAL OF 
 
 trace on a slip of glass after it has evaporated, the 
 sand which contains the foraminifera may be freed 
 from the benzole by using the liquor potass, and then 
 warm water. Gatherings of foraminifera should be 
 tested to see whether there are any diatoms, by dis- 
 solving the shells by the aid of hydrochloric acid, 
 when, if there are any diatoms, they will be left 
 nearly pure ; if not quite so, finish by the sulphuric 
 acid process (see paragraph 127). Sections of foram- 
 inifera should always be mounted to show their struc- 
 ture, in the same way as for diatoms, (see Plate 12). 
 
 136. Hairs (Animal) are best soaked in benzole, and 
 then transferred to turpentine, remaining in it for a 
 week or two before mounting in balsam or dammar. 
 
 137. Hairs (Vegetable) are mounted dry, in fluid, 
 and in balsam or dammar if for polariscope. As a 
 general method I should recommend fluids like 
 Recipes 12, 56, 76, &c., using a shallow cell (see 
 Chapter 4) ; they are sometimes mounted in their 
 natural position on the cuticle (see slide 10). Inter- 
 esting forms are from Antirrhinum (flower), Draba 
 (leaf), Tradescantia (stamen), Yerbascum (leaf), 
 Deutzia (leaf), Digitalis (corolla), Viburnum (leaf), &c. 
 
 138. Horn and Hoofs. Sections are made by placing 
 them in hot water, which renders them soft. Cut 
 sections with razor. 
 
 139. Injection is the method of filling the vessels of 
 animals with a coloured fluid, which may be of an 
 opaque, transparent fluid, or semi-fluid nature. It 
 requires a special set of apparatus, consisting of a 
 syringe (Pig. 87. ), pipes with stopcocks, &c. The 
 operation of injection is here shown, and at Pig. 88 
 the method of using the syringe, which has been filled 
 
MICROSCOPIC MOUNTING. 
 
 129 
 
 with a suitable fluid (see Hecipes 39, 40, 42, &c.) 
 Bullnose forceps are also much used to prevent the flow 
 of the coloured fluid if it escapes. The operation of 
 
 Fig. 87. 
 
 injection may be considered tolerably easy in action, 
 
 but requiring much practice. Pill the syringe (Fig. 87) 
 
 with the required coloured fluid, which must be kept 
 
 warm if it contains gelatine; put the pipe into an artery 
 
 or vein, tie waxed thread over the projecting arms and 
 
 round the artery itself, so as to prevent its slipping off, 
 
 then gently press the piston 
 
 of the syringe, so as to force 
 
 the fluid into the artery (see 
 
 Pigs. 87 and 88). This must 
 
 be done very gently, or the 
 
 fluid will escape either from 
 
 the object injected, or force 
 
 its way where the artery is 
 
 tied to the mouth of the 
 
 syringe. This, in a few 
 
 words, as space does not 
 
 permit of more, is the plan commonly pursued in 
 
 injecting. I prefer another method, which, though 
 
 it may be considered a primitive plan, I find 
 
 useful. I take a small Woulff's bottle (Fig. 18), 
 
 which I fit up with fine metal tubes in the same 
 
 FIG. 88. 
 
130 A MANUAL OF 
 
 manner as described for the wash bottle (Pig. 13). 
 On to the exit tube I fit one of the ordinary inject- 
 ing pipes. I do this with the aid of a bored velvet 
 cork, or I have the metal tube made to terminate 
 into a long capillary tube. I run this into the 
 artery or vein that is to be injected, tie round with 
 waxed thread, and also use, if necessary, the electrical 
 cement (Recipe 6), to make all tight. I then blow 
 gently into the bottle, when the injecting fluid, which 
 has been previously placed in the bottle, will flow into 
 the capillary tube and artery to be injected. 
 
 As a slight guide to the student, we will give the 
 plan to be followed in injecting a frog. "An incision 
 is made through the skin, and the sternum divided in 
 the middle line with a pair of strong scissors ; the two 
 sides may easily be separated, and the heart is 
 exposed. Next the sac, in which the heart-is contained 
 (pericardium), is opened with scissors, and the fleshy 
 part of the heart seized with the forceps ; a small 
 opening is made near its lower part, and a considerable 
 quantity of blood escapes from the wound ; this is 
 washed away by the wash bottle (Pig. 13). Into the 
 opening the tip of the heart being still held firmly 
 by the forceps a pipe is inserted, and directed upwards 
 towards the base of the heart, to the point where 
 the artery is seen to be connected with the muscular 
 substance. Before the pipe is introduced, however, a 
 little of the injecting fluid is drawn up so as to fill it ; 
 for if this were not done, the air contained in the pipe 
 would necessarily be forced into the vessels, and the 
 injection would fail." The point of the tube can, with 
 very little difficulty, be made to enter the artery. The 
 artery is then tied firmly to the pipe (not too high up, 
 
MICROSCOPIC MOUNTING. 131 
 
 or it will force its way through the artery), and the 
 animal injected in the usual manner. 
 
 The systems of vessels are generally injected with 
 different colours, like veins, white or blue; arteries, red; 
 urinary tubes, yellow, &c. The organs or small 
 animals, after being injected, may be kept in glycerine 
 or alcohol. Sections of them are cut with the 
 Valentine' s knife (Pig. 15) . If the coloured fluid in the 
 Woulff's bottle contains gelatine, it should be kept 
 warm by a hot- water plate during the process of injec- 
 tion. The best way to kill small animals when they 
 are to be injected, is to let them fall from a height. 
 The vessels of the animal will then be found to be in 
 a fit state. Inject as soon as possible. It is as well to 
 begin on the fresh kidney of a sheep or pig, a frog 
 (as before described), mouse or rat, or a piece of an 
 intestine (see Pig. 88) may also be tried. 
 
 140 Insects (mounted entire). It much depends 
 upon the order of insect how they are mounted. Eor 
 instance, the coleoptera, or beetles, nearly always show 
 best when mounted as opaque objects. Lepidoptera, 
 or moths and butterflies, are rarely mounted whole ; 
 if so, only micro-lepidoptera, which are mounted in 
 an opaque cell like the beetles. Diptera, or flies ; 
 hymenoptera, or bees, ants, &c. ; aphaniptera, or fleas; 
 neuroptera (especially the larva), and the anoplura, or 
 lice, comprise the insects that are mounted as trans- 
 parent objects, the method of treatment being again 
 according to their size and the nature of their body. 
 If delicate and small, like the anoplura, they are 
 mounted as recommended at Chapter III., under Slide 
 25 ; if firmer, like the small diptera, they must be 
 placed in a weak solution of potass for a short time, 
 
 K 2 
 
132 A MANUAL OF 
 
 to get rid of the extraneous matter in the abdomen and 
 thorax ; or if this solution is found to be too strong, 
 get rid of the matter by pressure between blotting- 
 paper. In any case they are well washed, dried under 
 pressure, and mounted in balsam or dammar (see 
 Chapter III.), or else mount in glycerine- jelly. If the 
 insect is still larger and firmer in its tissues, as in the 
 case of large flies, bees, &c., a very small hole may be 
 made with a needle in the under part of the abdomen ; 
 then place the insect in a tolerably strong solution of 
 potass, and allow it to remain until the contents of 
 the abdomen, &c., come away ; this process may be 
 assisted by occasionally pressing it gently between 
 two glass slips; when quite free, well wash, and mount 
 in balsam as usual (see Chapter III.). 
 
 141. Palates, or tongues of the mollusca, after being 
 dissected as mentioned at paragraph 127, require 
 cleaning with the solution of potass ; then well wash 
 and mount in a cell with glycerine, or dry and mount 
 in balsam for the polariscope. 
 
 142. Petals of Flowers. Tear the cuticle of the 
 petal off by using the forceps, or place the petal on a 
 glass slip and gently scrape the tissues away until the 
 under cuticle is left on the glass ; or mount the entire 
 petal in glycerine, using the fluid as recommended at 
 slide 45 ; but previous to this, place the petal in 
 alcohol to get rid of some of the colouring matter con- 
 tained in the cells ; but soon after it has been placed 
 in the glycerine solution, add a drop or two of sul- 
 phuric acid, which will restore the colour. Mount in 
 glycerine or glycerine-jelly. 
 
 143. Pollens are best collected in the anthers of the 
 flowers, choosing a dry day ; they are then stored in 
 
MICROSCOPIC MOUNTING. 133 
 
 pill boxes. If rather small and transparent, mount 
 them dry ; if at all opaque, mount them in a shallow 
 cell, using essential oil of lemon. A few good pollens 
 are, evening primrose, valerian, common mallow, 
 geranium, convolvulus, chicory, musk, passion flower, 
 &c. Glycerine may he tried for mounting some of 
 them, if the fluid recommended under slide 45 is pre- 
 viously used. 
 
 144. EapMdes (or plant crystals) . These beautiful 
 natural crystals consist of either oxalate, carbonate, 
 phosphate, or sulphate of lime, and may be distin- 
 guished by the proper chemical tests (see Chapter VII.) 
 The part of the plant containing them must be dried 
 under pressure, soaked in turpentine, and mounted in 
 balsam. They then show well under the polariscope, 
 though sometimes they may be mounted dry. The 
 plants that contain them in largest quantity are 
 orchids, lilies, hyacinths, cacti, spurges, nettles, 
 geraniums, the umbelliferse, &c. 
 
 145. Rock Sections. A description of the general 
 method of preparation of these sections is given at 
 paragraph 35. Many persons prefer to use glass one 
 and a half or two inches square, both for the grinding 
 and also the mounting of the sections, they being 
 much less liable to fracture than the ordinary three 
 inches by one slips. This size might be taken 
 advantage of for other specimens, such as bone, 
 teeth, &c. 
 
 146. Scales of Plants. These bodies are generally 
 taken from the leaves and stem, with the point of 
 a fine scalpel ; place in the centre of a glass slip, cover 
 with a drop of turpentine, and mount as usual. 
 
 147. Scales of fish are cleaned with a weak solution 
 
134 A MANUAL OF 
 
 of potass, and mounted dry, or in balsam. Use a fine 
 hog's hair brush in cleaning them. 
 
 148. Scales of insects, almost always mounted dry ; 
 rub the wing or insect on a slightly damped slip, 
 when the scales will adhere. Mount in a shallow cell 
 dry (see Chapter II.) 
 
 149. Seeds should generally be mounted " dry 
 opaque," but sections should be taken, especially of 
 the testa, so as to show the structure and form of the 
 cells, which are often very peculiarly beautiful in 
 form. These sections, if too thick for the " dry 
 transparent," may be preserved by the "fluid" or 
 the Canada balsam process." If the testa is at all 
 oleaginous or oily, it is better to mount the section 
 in a suitable fluid (see Hecipes 14, 57, 58, &c.) 
 
 150. Staining tissues. The section of tissue to be 
 mounted is cut with a simple broad razor, well covered 
 with alcohol or water, the tissue being embedded in a 
 mixture of wax and oil, poured into a small paper tray 
 if necessary. The section is then placed in a solution 
 of carmine (see Hecipe 47) till sufficiently stained, 
 i.e., three to twenty minutes. Then it is well washed 
 under a stream of water from the wash-bottle (Pig. 
 13) ; then place it for half a minute in a watch glass 
 full of water, with one drop of acetic acid added 
 thereto, thence into absolute alcohol, After ten 
 minutes in this, all the water being extracted, it is 
 placed in oil of cloves, which completely clears it in a 
 minute or two ; it is then mounted in a solution of 
 gum dammar in turpentine. Perfectly fresh tissues 
 are placed in the solution of silver (Recipe 30), left in 
 it for about ten minutes, washed and mounted in 
 glycerine, and exposed to sunlight for half an hour or 
 
MICROSCOPIC MOUNTING. 135 
 
 more ; then finished as usual with fluid preparations ; 
 or they may be transferred to absolute alcohol, and 
 mounted in the same way as the carmine section. 
 
 The following solution for staining tissues, which 
 is used by Mr. Bevan Lewis, will be found good, 
 especially for all animal tissues : 
 
 100 cc distilled water. 
 
 ! ( Chloride of gold 
 
 T^O gramme | and potassi * m . 
 
 Dissolve and keep in stoppered bottle. 
 
 In the case of Beale's carmine solution, the prepa- 
 ration ! should be washed with a one per cent, solution 
 of glacial acetic acid. 
 
 In the case of many histological structures, no ap- 
 parent structure is visible, but on the application of 
 alcohol, many of the nerve fibres, cells, &c., will 
 appear as its evaporation proceeds. This appearance 
 may be fixed by suddenly dropping over its surface a 
 little Canada balsam, and permanently mounting. 
 
 Judson's Aniline dyes will be found useful, especially 
 the black, but where black requires to be used, I much 
 prefer Doctor Elizabeth Hoggan's process, the recipe 
 for the preparation of the solution being described in 
 the appendix, Recipe 35. 
 
 "The section or membrane to be stained is first 
 treated for one or two minutes with alcohol ; the iron 
 solution is filtered upon it, allowed to remain for a 
 couple of minutes, and then poured off. The pyro- 
 gallic acid solution is then filtered in a similar way 
 upon it, and in the course of a minute or two, the 
 desired depth of staining having been obtained, the 
 tissue is washed, and may be mounted in the usual 
 manner, either in glycerine, balsam, or varnish. 
 
136 A MANUAL OF 
 
 The nuclei and nucleoli will be found coloured 
 black, and the cell substance will also be coloured 
 more or less, according to the age and other conditions 
 of the cell. A bluish tint may be given to them by 
 washiDg the section with an alkalire water." This 
 process is especially useful for photographic purposes, 
 and to those who can only work with the microscope 
 in artificial light, the definition being very clear and 
 distinct. It is probably the best process for staining 
 silvered preparations, as it has no effect on the black 
 lines, while it makes the nuclei very distinct. To 
 avoid staining the fingers the filtering paper should be 
 held with the forceps. 
 
 A process of staining soft tissues, especially animal, 
 is now much used ; it consists of first staining the 
 tissues with the logwood solution, and then immersing 
 them for a few seconds only in a solution of aniline 
 black, strength -^-^th per .cent. ; place in hydrate of 
 chloral, wash with water, and then rapidly dehydate 
 by use of alcohol, clean with oil of cloves, then tur- 
 pentine and mount in balsam. 
 
 151. Starches. : The best plan to obtain starch is to 
 grind or cut the root, stem, seed, or grain, into very 
 small pieces, and finish in a mortar ; then place this 
 powder into a small fiannel bag, cover with two thick- 
 nesses of muslin, and with the fingers press and 
 agitate it in a glassful of water, using, if possible, a 
 conical vessel like Pig. 119 ; the water will then 
 assume a cloudy or milky appearance, which, as the 
 vessel is allowed to stand some time, will settle as 
 starch at the bottom of the vessel. The gluten and 
 other parts left in the bag must be thrown away, and 
 the bag well washed and freed from starch, &c., before 
 
MICROSCOPIC MOUNTING. 137 
 
 using for any other root, &c. Starches are mounted 
 dry, in fluid, and in balsam (see Chapters III., IV.) 
 
 152. Teeth. Sections are cut with the fine saw 
 (Pig. 22), the teeth heing placed in the holding- 
 screw (Pig, 6) ; they are then ground down to the 
 required thickness in the same way as sections of 
 bone (paragraph 111) ; but some kinds of teeth for 
 instance, elephants, are too hard for this treatment ; 
 they must then be cut and treated hi the same way as 
 rock sections (see paragraph 35.) Sections of teeth 
 are generally mounted dry; but if the whole tooth 
 has been placed in diluted hydrochloric acid, sections 
 are cut with the razor, and may then be mounted in a 
 suitable fluid, like Recipe 74, or else in balsam or 
 dammar. 
 
 153. Trachece of Insects are tolerably easy to dissect, 
 especially from Iarva3, in which case the body is cut 
 open and the contents washed out with a camel's 
 hair brush, using a weak solution of potass if any 
 diniculty is found in removing the matter, but the 
 larvae must not be allowed to remain in the solution, 
 or the tracheae will be spoilt ; when quite clean, wash 
 well with water, and mount in a cell with suitable 
 fluid, or sometimes they are dried and mounted in 
 balsam. 
 
 154. Vallisnerla, Chara, and Anacharis, and a few 
 other plants all show the circulation of the protoplasm 
 or cell contents. Pig. 89 illustrates a slice cut from 
 the leaf of the vallisneria, exposing the cells ready for 
 examination ; occasionally, the circulation cannot be 
 observed without a slight degree of warmth is ob- 
 tained. The slice should be placed on a glass slip, 
 covered with a drop of water and a piece of thin glass. 
 
138 
 
 A MANUAL OF 
 
 FIG. 
 
 155. Wood (Sections of). Although green wood is 
 
 never used for cutting into 
 sections, still it is always the 
 best plan to place the wood 
 that you are about to cut 
 sections from, in water, for at 
 least two or three days pre- 
 viously. Some persons pre- 
 fer to place the wood in 
 alcohol for a day or so before 
 they soak it in water. If the 
 sections curl up at all after 
 being cut, they must be placed in water, and then 
 dried under pressure. Razors and other instruments 
 are used in cutting the sections (see paragraph 3.) 
 
 156. To imbed objects in gum, place them in a 
 funnel made out of blotting-paper, which must con- 
 tain a concentrated solution of gum. Suspend the 
 cone in absolute alcohol (methylated spirit will do 
 well, and is cheap), when, in the course of a few days, 
 the gum will acquire sufficient solidity to allow of its 
 being cut together with the object; this is a good plan 
 for many objects that require a support previously to 
 sections being cut from them. 
 
MICROSCOPIC MOUNTING. 139 
 
 CHAPTEE VI. 
 
 ON THE COLLECTION AND HOUGH PRESERVATION OP 
 SPECIMENS, WITH NOTES ON THEIR HABITS, &C. 
 
 157. MANY objects are often lost which would not be 
 the case if a slight knowledge of their rough preservation 
 had been gained, and their beauty is often impaired by 
 their being placed in an improper medium; as a general 
 rule, very small insects keep well, when it is desired to 
 store them, in acetic acid, to which 25 per cent, of 
 alcohol has been added; but, of course, this rule is liable 
 to certain exceptions, for instance, nearly all the small 
 weevils directly they are caught require to be "set," as 
 it is called, or the legs get so stiff that it is almost im- 
 possible to place them in their right position afterwards. 
 The only way ' if this does occur from want of time, 
 &c., is to relax the muscular parts by the use of laurel 
 leaves. The weevils or other small beetles, &c., are 
 placed in a bottle containing these leaves, which have 
 been bruised in a mortar. The insects will then be found 
 to be slightly relaxed ; so much so that they may be 
 " set " or mounted in their proper cell without any 
 part being broken, if only moderate care is taken. 
 These insects are generally fixed in rows on long strips 
 of card-board, the legs being set in their proper posi- 
 tion by the aid of a solution of gum tragacanth. 
 Pig 48 represents a collecting bottle used for collecting 
 these and other small insects. 
 
140 A MANUAL OF 
 
 We will now treat the subject of collection system- 
 aticalJy under the following four heads, i.e. : 
 
 1. How to collect. 
 
 2. Where to find. 
 
 3. Rough preservation, with storing, labelling, and 
 postage of specimens. 
 
 4. The classification of microscopical and biological 
 objects. 
 
 I. HOW TO COLLECT. 
 
 158. The following instruments which are absolutely 
 necessary for collecting specimens, are drawn on stone 
 at Plate 7 : All the instruments with the exception of 
 the forceps net, Eig. 93, have a hole turned in them, 
 carrying a screw-thread of exactly the same size in 
 each tool, so that the same rod (whether telescopic, and 
 fitting into a walking-stick) or single, can be used. 
 Eig 90 represents a wide-mouth bottle fixed into a ring, 
 but removable upon the slide (a), being slipped from off 
 the elastic-like joint ; this bottle is used'f or collecting 
 small water insects, &c. Eig. 91 is a spoon fitted so 
 that the rod can be removed at will, as before described; 
 it is used for scooping up diatoms and desmids from 
 the surface of mud, the rod being used when they are 
 out of reach. Eig. 92 is a net used for catching butter- 
 flies, moths, and other winged insects. A stronger net 
 must also be used for water insects. 93 represents a 
 forceps net, very useful for catching beetles and small 
 flies whilst in the act of resting on leaves. 94 is a 
 kind of two-pronged rake ; it is used for dragging 
 water- weeds when out of reach of the collector. 95 is 
 a useful tool used for cutting weeds, taking pieces off 
 
/ 7. 
 
 o 
 
MICROSCOPIC MOUNTING. 
 
 141 
 
 the bark of trees, and in all cases where a small lever 
 and cutting instrument is required. 96 is a digging 
 tool used for raising bulbs, roots, &c., and in search- 
 ing for chrysalis. 97 is a pill-box filled with 
 plaster of Paris, with a hole scooped out of the 
 top. Pig. 100 is a separate woodcut of a surface 
 net, improved by Mr. Highley : this is made of 
 bunting, stretched upon a cane hoop 
 and supported by cords ; the inner 
 cone is much shorter, it is used to 
 prevent objects being washed out 
 again. At the bottom of the bag 
 is fixed a glass bottle, and a bung is 
 attached to it, with a cord to prevent 
 its sinking too deep. This net is used 
 in collecting marine objects, being 
 towed at the end of a boat ; the bottle 
 must be emptied into others occasion- 
 ally. In marine collecting, a dredge 
 should also be used. Pig 98 rep resents 
 the corner of an envelope cut off to Fig. 100. 
 
 the required size : these will be found most useful for 
 collecting all small specimens especially vegetable, like 
 mosses, lichens, &c. Pig. 99 is one of the cell-holders 
 which slide into the rack-box, Pig 101 ; the left-hand 
 circle represents one of the ebonite rings which are 
 used for cells, and the right-hand black disc shows one 
 of the circular holes into which they fit ; the second 
 circle from the left shows the back of one of the cells, 
 and the next circle represents one of the cells having an 
 insect mounted in it ; for further description of these 
 cells, see Paragraph 210. Pig. 101, plate 8, shows the 
 section of a rack-box containing six of the shelves or 
 
142 A MANUAL OF 
 
 cell-holders, like the one at Pig. 99 ; a full description 
 of these boxes, &c., is given at Paragraph 210. Fig. 102 
 also shows a square slah of wood as drilled with holes 
 to receive bottles, &c., used in storing specimens, a full 
 description of which is given at Paragraph 208. A 
 modification of this arrangement will also answer well 
 for the collection of objects ; two blocks of wood, like 
 Pig. 102, should have holes drilled in them of a suit- 
 able size, and in the same position in both blocks, so 
 that upon being placed together the holes should meet; 
 when used for collecting, one block must be filled with 
 the right-size bottles so as to fit rather tightly, the 
 other block must then be placed so that the tops of the 
 bottles fit into it ; two stout india-rubber bands must 
 be passed over the blocks to keep them together. By 
 this plan, specimens can be carried in bottles without 
 much risk. 
 
 159. When much collecting is done in a marshy 
 district, or if the collector cares more for the algse and 
 other water plants, &c., it is well to have the pockets 
 of his coat lined with oiled silk ; this plan will be 
 found very convenient. 
 
 160. Pine muslin stretched tightly over a large ring 
 about 1 foot in diameter, will also be found very use- 
 ful, when fixed to the rod, for catching small water 
 insects, &c., also for gathering desmids when floating 
 in the water. 
 
 161. Tin boxes 4| inches long by 3 inches wide, 
 also sardine tins, &c., some of which must be lined 
 with cork, will be found very convenient, and a tin 
 sandwich box is also very useful for small plants, 
 &c. 
 
 162. Before using the collecting bottle, Pig. 48, a 
 
MICROSCOPIC MOUNTING. 143 
 
 small piece of muslin must be put inside to allow foot- 
 hold for the insects, otherwise the beauty of many of 
 them might be impaired. 
 
 163. When beating bushes and low trees for beetles 
 and other insects, always lay a white linen cloth, about 
 4 feet square, under the part that is about to be beaten 
 for the insects to fall on ; it is as well always to carry 
 this cloth in the coat pocket when out collecting. A 
 small square of india-rubber cloth will also be found 
 very useful when kneeling in damp places. 
 
 164. It is also advisable to carry two small books 
 made of blotting-paper, one of them 5 inches square, 
 the other 2 inches square, the largest to be used for 
 small plants, flowers, petals, leaves, &c., and the other 
 for small flies, mites, and other minute insects ; both 
 of these books will require to be kept well together by 
 the aid of elastic bands after the specimens have been 
 placed in them. 
 
 165. It is also a very good plan to keep a rough 
 note-book in the pocket, in which to enter notes of the 
 specimens collected, locality where found, &c., for if 
 not done at the time, it is forgotten, and often much 
 valuable information lost. 
 
 166. In using the bottle, Fig. 90, for the surface of 
 the water it must be held sideways, with the mouth 
 partly below ; but if it is desired to catch any 
 insect beneath the surface of the water it must be 
 carried under with the mouth downwards, so that it 
 remains full of air when brought near to the insect or 
 object it is desired to catch ; it must be turned so that 
 the mouth will point upwards ; the insect together 
 with the water will then rush in, and may be brought 
 to the surface, and the bottle emptied into another, or 
 
A MANUAL OF 
 
 the insect caught "by pouring the water over the water- 
 net, when it will he caught in the meshes. 
 
 167. Blights, "brands, and other forms of micro- 
 fungi, such as the well-known hramhle leaf hrand, &c., 
 are best collected in corners of old envelopes. (See 
 Fig. 98). 
 
 168. Desmids are generally collected when in mud, 
 where they often are found in large quantities, giving 
 a greenish tint to the surface, by scooping the surface 
 with the spoon (Pig. 91). The mud must then be put 
 into cases made with oiled silk or sheet gutta-percha. 
 They are cut out like a small envelope, and the flaps 
 folded over and cemented there by the aid of the 
 india-rubber cement (Recipe 5). When found in 
 smaller quantities it is generally on conferva, water 
 moss (Fontinalis) , &c. The best way will be to wash 
 the moss, &c., in a bottle of fresh water, letting the 
 desmids and other matter fall to the bottom. Repeat 
 this until a good gathering is obtained. The green 
 scum on the top of ponds must also be examined. 
 Eor this purpose a good Coddington lens is required. 
 The collector should always carry one of these lens 
 with him. Half-dried pools and puddles of water 
 should always be examined, as they are often rich in 
 desmids, diatoms, &c. It is desirable to preserve or 
 mount, as soon as possible, all forms of algae, and con- 
 ferva, more especially desmids, as they soon lose their 
 colour and begin to decay. 
 
 169. Diatoms are known from desmids by their 
 being of a brown colour, often giving a rusty brown 
 appearance to the surface of mud, whilst desmids are 
 always green. They are collected with the spoon 
 (Fig. 91), in the same manner as with desmids. 
 
MICROSCOPIC MOUNTING. 145 
 
 "When found growing on masses of conferva and algae 
 they must he well ruhhed, and then washed in a hottle 
 of pure water, when the diatoms and other matter will 
 sink to the hottom. In gathering the algse, &c., for 
 this purpose, when out of reach, use the rake (Fig. 94), 
 which must be fitted into the rod. If new sponges 
 are washed in water, and the deposit at the hottom 
 of the vessel collected, there will often be found good 
 forms of marine diatoms. When at the sea- side, 
 always wash a large quantity of sea-weed in fresh 
 water, and collect the deposit ; then bottle in spirit 
 for future use. The alcohol will prevent any decay, 
 and keep the diatoms until ready for the cleansing 
 process (Chapter V., Paragraph 127.) 
 
 170. To obtain amoeba and other infusorial animal- 
 cula, hay and other vegetable matter must be kept in 
 a small quantity of water until it begins to decay. 
 They will then be found in the water when subjected 
 to examination under the microscope. A small piece 
 of meat allowed to decay in water also produces good 
 animalcula. Amoeba are almost certain to be found 
 in the green frothy scum of puddles and pools of 
 stagnant water. 
 
 171. Water fleas and other small water insects are 
 caught by using the bottle (Fig. 90) or a small water 
 net. If caught in a bottle, pour the water over a 
 small piece of white linen rag, when they will be seen 
 with the naked eye. Collect and store in small 
 bottles, keeping each species separate if possible. 
 
 172. The best way to obtain many of the larger 
 insects is to collect them, not in the perfect or imago 
 state, but in the larva or pupa stage, and keep them 
 until they emerge as a perfect insect. The advantage 
 
146 A MANUAL OF 
 
 of this plan is, that, as well as the insect, the eggs may 
 also be obtained. This is desirable, for as well as 
 being rather a new field for investigation, these 
 objects are often of great beauty. My plan, or rather 
 one that the Rev. J. G. Wood kindly suggested to me, 
 is as follows : take a common white jam pot, fill it f rds 
 full of water, then in the middle of a common saucer 
 drill a hole about fths of an inch in diameter. 
 Through this hole pass the spray of the plant that 
 the larva feeds on, and over all (or some prefer only 
 over the plant), place a lamp chimney or a common bell 
 or propagating glass. The water in the pot, of course, 
 keeps the spray of the plant green, for a moderate 
 time, but it is desirable to replenish it tolerably often. 
 By this plan larva may be kept, and moths made to 
 deposit their eggs upon the plant that is natural to 
 them. Another plan is to place slips or cuttings of the 
 plant that the larva or moths like, into a pot half full 
 of earth ; cover this with muslin, kept in its place 
 with an elastic band passed over the rim of the pot. 
 
 173. Gall Insects (Cynips), The best plan to ob- 
 tain these insects is to keep the galls under a bell glass, 
 or in a box having a glass lid, until they emerge. 
 They are sometimes mounted whole, but generally 
 the saw which is at the apex of the abdomen is the 
 only part mounted. 
 
 174. Podurce are small insects found generally 
 in damp cellars, &c., well known for having minute 
 scales, which are a favourite test-object to the micro- 
 scopist, may be caught by placing over them a glass 
 tube a test tube will do as well. They jump into the 
 tube. A finger must then be applied to the mouth, 
 and a small quantity of tobacco smoke, fumes of 
 
MICROSCOPIC MOUNTING. 147 
 
 sulphur, &c., let into it ; in a short time they will be 
 killed. 
 
 175. Mosses may he collected in small pill boxes, 
 each species being kept in a separate box. 
 
 176. To catch the greater water-beetle (Dytiscus 
 marginaUs), and other water beetles, large larva, &c., 
 the best plan is to tie a piece of thread tightly round 
 the middle of a small worm, and let it into the pond, 
 the other end of the thread being fixed to a long stick, 
 or the rod that is generally carried. Newts often take 
 this bait also. 
 
 177. Zoophytes. I find the best plan is to carry a 
 moderately wide mouth bottle filled with spirit 
 methylated spirit will do; wait until a wave passes 
 over the zoophytes, or plunge them into sea water for 
 a few minutes after collection, then immediately drop 
 them into the spirit. By this plan their tentacles will 
 be found to be well extended. 
 
 178. In searching woods and fields for various 
 micro-fungi, insects, &c., it must not be forgotten to 
 sometimes collect seeds of wild flowers, small flowers, 
 petals, leaves, stems, &c., which examine well after 
 being brought home, or. 
 
 179. A good plan, if out for a long day's collecting 
 excursion, is to forward your working microscope, 
 with st^ck of thin glass slips, &c., to any cottage in 
 the centre of the local district that you are about to 
 explore, care of course being taken that the micro- 
 scope is under lock and key, and no children about. 
 Prom this cottage, as your local centre, radiate your 
 short excursions of a mile, or half mile, bringing the 
 specimens collected back to the cottage occasionally. 
 By this plan much worry and fatigue of carrying 
 
 * 2 
 
148 A MANUAL OF 
 
 what you do not require at the exact time, and also 
 the comfort of examining fresh specimens under cover 
 and free from wind, &c., will be found a very great 
 advantage. 
 
 180. When out for short excursions only, it is as 
 well to collect only one kind of thing say, for instance, 
 pollens. By this plan better work will be done than 
 if you collected first pollens, then butterflies, then 
 seeds, &c. 
 
 181. Butterflies. When catching these beautiful 
 insects, the best and less fatiguing plan is to allow 
 them to settle on a plant, and then cast the net over 
 them in the usual manner. Kill by a nip or pinch 
 between the legs. This severs the nerves, and 
 generally kills them. 
 
 182. Moths are caught chiefly at night time. The 
 best plan is by, technically called "sugaring," as 
 follows : 
 
 Take 1 pint of old ale. 
 
 1 pound coarse sugar. 
 1 pound treacle. 
 
 Mix and simmer together, but do not boil ; when cold, 
 add a wine-glassful of rum keep this in a large 
 bottle. On any dark warm night from April to 
 September, go into an orchard or wood, carrying a 
 lantern with you ; then paint a few trees with the 
 mixture, using a common paint-brush. Return to 
 the trees in about twenty minutes, when, if it is a 
 successful night, various moths will be found sucking 
 the liquid ; they may then be beaten into the open 
 butterfly net (Pig. 92), which must be held below 
 them. Paint in patches of about seven or eight inches 
 
MICROSCOPIC MOUNTING. 149 
 
 square ; do not use too much of the mixture for each 
 patch ; kill the moths in the same manner as butter- 
 flies ; but if it is desired to keep them to lay eggs, 
 place a small quantity of leaves in a tin box ; put the 
 moths in, and when arrived at home, give them a 
 slip of the plant that is natural to them (see para- 
 graph 172). 
 
 183. Foraminifera. When at the sea-side, examine 
 the sand well ; also old whelk shells, &c., that have 
 been driven in after a gale ; but the best forms are 
 always obtained by dredging the bottom some dis- 
 tance from the shore. Tenby, Wey mouth, Isle of 
 Wight, coast of Cornwall, and north-west coast of 
 Devon, are about the best places to obtain good 
 foraminiiera, they being driven in-shore by the wash 
 of the Atlantic. 
 
 184. When out collecting, do not carry many 
 things, as for a general rule, the less apparatus taken 
 the more specimens obtained ; rough and ready means, 
 like old envelopes, pill-boxes, &c., will be found the 
 best in the long run ; and when apparatus must be 
 used, care should be taken that it all fits into one 
 common box or bag, the parts also fitting into one rod 
 (see Plate 7). 
 
 H. WHERE TO FIND. 
 
 185. The green weevil, often called the British 
 diamond beetle, is found on the leaves of the com- 
 mon hazel (Corylus Avellana). The best time to 
 collect most beetles is in the spring and autumn 
 
150 A MANUAL OT* 
 
 months, when masses of dead leaves, mushrooms, and 
 other fungi, should be examined, also the hollow 
 stems of cut wheat, &c.; and in the winter, mosses 
 and tufts of grass will be found likely places. The 
 common oil beetle ( Meloe proscardbceus), which may 
 be known from its peculiar blackish blue colour, has 
 good gastric teeth, and will be found one of the best 
 beetles on which to begin to dissect. The greater 
 water-beetle (Dytiscus Marginalia) is also good. This 
 may be found on on masses of weeds in the middle of 
 ponds. All beetles should be examined for their 
 gizzards and gastric teeth, especially the larger species. 
 
 186. Butterflies are often found in large numbers 
 in clover fields, and also on chalk downs, such as 
 those near Canterbury, &c. 
 
 187. Fresh-water Shrimps are found in nearly every 
 stream, especially when it has a gravelly bottom. 
 When small, they are interesting objects, both alive 
 and preserved. 
 
 188. Water-flea^ are also found in nearly every fresh 
 water pond and pool, especially if covered with duck- 
 weed. 
 
 189. Floscularia cornulata, and other rotatoria, are 
 found on fresh-water plants, particularly water-moss 
 (Fontinalis) . 
 
 190. I have a very good pocket microscope for 
 observing these and other animalculae, &c. It is sold 
 by Mr. Wheeler, of Tollington lload, Holloway, 
 London. The price I think was about a guinea. 
 
 191. Hastings and Torquay are both good places 
 for zoophytes. Devonshire, Cornwall, south-west coast 
 of Wales, are good for seaweeds. Occasionally a few 
 good species may be found at Hastings. Collect at 
 
MICROSCOPIC MOUNTING. 151 
 
 the very lowest spring and autumn tides on the sea- 
 ward side of rocks. 
 
 192. Sphacellaria cirrhosa is a very good seaweed 
 for showing the antherozoids or spores when the weed 
 is mature ; it is tolerably common and parasitic upon 
 larger alga3. 
 
 193. Marine diatoms are generally found on seaweed. 
 
 194. Marshes are good places to find diatoms, par- 
 ticularly salt marshes like Erith, Dartford, &c. 
 
 195. Guano various samples should he well 
 searched for diatoms. Fossil earths, such as Oran, 
 Toome Bridge, Bermuda, &c., are composed entirely 
 of diatoms, hut do not, as a rule, yield a great variety 
 of species. Eresh diatoms are found nearly every- 
 where in ponds, pools, puddles, round ponds, &c., 
 either on water-plants, or on the surface of the mud 
 round the edge of the pond. 
 
 196. Desmids may he looked for in ponds placed in 
 exposed situations, like Hampstead heath, the ponds 
 on Tunh ridge Wells common, &c. Spring and 
 autumn is the best time to collect these and other algae. 
 
 197. Mosses are found on shady and damp banks, 
 rocks, woods, &c., and some species, like funarla 
 hygrometrica, on special places, as this species 
 almost always grows on a place after a fire, especially 
 if wood has been burnt, as in the case of encamp- 
 ments of gipsies, &c. A section of the capsule of 
 this specie shows the columella well. Some species of 
 moss are always common, like the common wall screw 
 moss (Tor tula muralis). 
 
 198. The bark of old trees, especially when 
 covered with lichens, &c., often affords a living, and 
 hiding, place for many minute insects, such as the 
 
152 A MANUAL OF 
 
 larvae of dermestes, and other small beetles, mites, &c. 
 March, April, and May are the best months to search 
 the bark of trees. 
 
 199. Podurce are often caught in wine-cellars, and 
 in many clamp situations, such as under stones, flower- 
 pots ; also under large leaves like the dock. A stale 
 cooked potato, an old meat bone, &c., form excellent 
 baits when placed in a damp cellar, as they live upon 
 decayed animal and vegetable substances. 
 
 200. The harvest bug (Tromhidium autumnale) may 
 be found in the hollow stems of the straw after the 
 wheat has been cut, or by dragging a damp hand- 
 kerchief through the stubble. They are minute 
 red insects. Earth mites (TetranycJms lapidmti) are 
 found in the crevices of stones, bark, &c. Eurze 
 mites on gorse bushes, between a thorn and the main 
 stem. 
 
 III. ROUGH PRESERVATION, LABELLING, AND POSTAGE 
 OF SPECIMENS. 
 
 201. It is always well to keep sufficient of the 
 material collected, for if not required for private use, 
 they can be exchanged with friends. Beetles, butter- 
 flies, moths, vegetable hairs, pollens, stems of grasses, 
 most seeds, sections of woods, feathers, bones, hoofs, 
 horns, fish scales, teeth, tongues and palates of molluscs 
 after rough dissection (see Chapter V., paragraph 128, 
 and also plate 6, G, Eigs. 84 and 85). Sponges, spores 
 of ferns, mosses, equisetacese, insect scales, mosses, 
 diatomaceous earths, shells, foraminifera, &c., are best 
 kept dry in small pill-boxes, suitable to the size of the 
 specimen or specimens. 
 
MICROSCOPIC MOUNTING. 153 
 
 202. Plies, bees, wasps, crickets, and other large 
 and fleshy insects, must be kept in alcohol. 
 
 203. Minute insects, such as parasites, acari, small 
 flies, &c., may be placed in the same fluid as recom- 
 mended for algae, &c. (see Chapter IV., under slide 45). 
 The spirit and water must be allowed to evaporate, 
 when glycerine will be left, if not sufficient fill up with 
 pure glycerine ; or they may be kept in acetic acid, to 
 which 25 per cent, of alcohol has been added, but this 
 will render them much more opaque than the glycerine. 
 If the parasites, &c., are to be mounted in balsam or 
 dammar, it is best to put them immediately into 
 turpentine, and not into either glycerine or alcohol. 
 This, of course, depends upon whether they are full of 
 blood, &c. ; if so they must be treated with the solution 
 of potass, as in Chapter III., slide 25. 
 
 204. Algae, especially the smaller kinds, such as 
 the conferva, desmids, &c., require to be roughly 
 preserved in the same medium as they are mounted in. 
 Glycerine will be found the most generally useful 
 substance, but care must be taken to add it gradually 
 (see Chapter IV., slide 45). 
 
 205. Zoophytes may be kept in the same bottle of 
 alcohol in which they are killed. 
 
 206. A good plan, where only a very small quantity 
 of desmids, small insects, &c., are desired to be pre- 
 served, is to fill pill-boxes with liquid plaster of Paris. 
 Let it set and harden, then scoop out a conical hole 
 in the plaster (see Pig. 97, plate 7). Place a small 
 piece of wax in this cavity, which absorb into the 
 plaster by the action of a moderate heat. The hole 
 or cavity will then be found very -useful for keeping 
 small quantities of specimens, either dry or in 
 
154 A MANUAL OF 
 
 glycerine, the lid of the pill-box forming a cover to 
 keep dust out. 
 
 207. Where objects are stored in fluids, bottles, of 
 course, must be used. The small homoeopathic bottles 
 will be useful for small quantities ; both these and 
 larger bottles must be kept upright, by putting them 
 into holes drilled of a suitable size in blocks of wood ; 
 a useful size for which is four inches square, and one 
 and a half inch deep (see Tig. 102, plate 8). Both 
 the pill-boxes and bottles must be kept in drawers of 
 a suitable size, divided into compartments as below. 
 It is as well to have three or more drawers labelled as 
 follows : 
 
 DRAWER 1. ANIMAL OBJECTS. 
 Roughly Preserved. 
 
 1. Vertebrata. 3. Articulata. 
 
 2. Mollusca. 4. Radiata. 
 
 DRAWER 2, VEGETABLE OBJECTS. 
 1. Elowering plants. 2. Mower less plants. 
 
 DRAWER 3. MINERAL OBJECTS. 
 
 1. Metallic Objects. 3. Crystals. 
 
 2. Hock Sections, &c. 
 
 208. White paper labels, with the name and date, 
 should be placed upon both boxes and bottles. Where 
 the objects are foreign, yellow labels should be used, 
 as it is a great guide in finding any object quickly. 
 
 209. The best plan for packing specimens of un- 
 mounted microscopic objects for postage, is to get a 
 block of soft wood ; deal is best, five inches long, one 
 inch deep, one inch wide, drill five holes, more or less, 
 and of different depths, according to objects. Pill 
 what place is left, after the specimens have been placed 
 
JHEZDMI iggr 'rah IBP-. Mjfli 
 
 r 
 
 TEH 
 
 Hffl 
 
 - ITFf ulflF! mill llljl HgT' "T|St iff'" *^B 
 
 
 BtBi 'iilti (BTnr~ ill 
 
 BET 
 
 I 
 
MICROSCOPIC MOUNTING. 155 
 
 in the holes, with cotton wool. Have a flat cover the 
 same size as the block, but only quarter inch thick. 
 Screw this cover to the block with three screws, one 
 in the centre, and one at each end. Over all, place 
 a gummed label containing the right stamp, name, 
 address, &c. If slides are sent, the small rack-boxes 
 made and sold especially for postage of slides, may be 
 obtained of Mr. Wheeler, Hollo way. 
 
 IV. THE CLASSIFICATION OF MICROSCOPIC SLIDES. 
 
 210. For rough observation, large quantities of 
 opaque objects may be stored in the ordinary rack boxes 
 (see Pig. 101, Plate 8). In this case they are tem- 
 porarily mounted in cells, which fit into wooden shelves 
 or plates, sliding into the grooves of the rack box (see 
 Pig 101). These cells are made as follows : One of 
 the vulcanite rings, f in diameter, has a disc of card- 
 board exactly the same size as the ring cemented to 
 one side of it ; this is blackened with Indian ink on 
 the inside. The object is mounted on this blackened 
 surface, using either Hecipe 1 or 2. The cell covered 
 with a thin glass circle to keep dust out. On the 
 other side, where a thin white disc of cardboard is 
 exposed, the name of the object, with date of collec- 
 tion is written. These cells are then dropped into 
 holes drilled in the sliding plates, which shelves fit 
 into the rack box (Pig. 101). Pour cells containing 
 objects may be placed on each plate. Twenty-four 
 objects can therefore be stored in the same rack box 
 which ordinarily only holds six. 
 
 211. But if money is no object, nothing can be 
 better for storage of slides than the pine cabinets sold 
 
156 A MANUAL OF 
 
 by most opticians, only each drawer must form one 
 of a series which, combined, should be of so compre- 
 hensive a character that a slide may be absorbed into 
 the whole without difficulty or disarrangement of the 
 series. 
 
 The following is a plan which I should recom- 
 mend : 
 
 A. 
 
 CABINET. ANIMAL KINGDOM. 
 
 VEKTEBHATA. 
 
 Drawer 1. Bone system. 
 
 Drawer 2. Muscular and fibrous systems. 
 
 Drawer 3. Nervous systems and organs of sense. 
 
 Drawer 4. Integumentary system. 
 
 Drawer 5. Nutritive system. 
 
 Drawer 6. Miscellaneous. 
 
 B. 
 MOLLUSCA. 
 
 Drawer 7, Classes, Polyzoa, Tunicata, Brachiopoda. 
 Drawer 8. Classes, Lamellibranchiata, Gasteropoda, 
 (tongues or palates), Pteropoda, Cephalopoda. 
 
 c. 
 
 ANNULOSA. 
 
 Class Imecta. 
 Drawer 9. Orders, Coleoptera, Strepsiptera, Hy- 
 
 menoptera. 
 Drawer 10. Orders, Lepidoptera, Diptera, Apha- 
 
 niptera. 
 Drawer 11. Orders, Hemiptera, Orthoptera, Neu- 
 
 r opt era. 
 Drawer 12. Orders, Thysanura, Mallophaga, Ano- 
 
 plura. 
 
MICROSCOPIC MOUNTING. 157 
 
 ARACHNIDA. 
 
 Drawer 13. Classes, Arachnida, Myriapoda. 
 Drawer 14. Classes, Crustacea, Chaetognatha, Anne- 
 lida, Gephyrea. 
 
 D. 
 
 ANNULOIDA. 
 
 Drawer 15. Classes, Echinodermata, Scolecida. 
 
 E. 
 
 CCELENTERATA. 
 
 Drawer 16. Classes, Hydrozoa, Actinozoa. 
 
 F. 
 PROTOZOA. 
 
 Drawer 17. Classes, Gregarinidse, Rhizopoda, In- 
 fusoria. 
 
 CABINET VEGETABLE KINGDOM. 
 
 G. 
 FLOWERING PLANTS. 
 
 Drawers 18 and 19. Reproductive system, including 
 
 seeds, pollens, &c. 
 Drawers 20 and 21. Epidermal tissues, including 
 
 petals, cuticles, hair, scales, &c. 
 Drawers 22 and 23. Cellular and vascular tissues, 
 
 including sections of leaves, &c. 
 Drawer 24. Sections of woods. 
 Drawer 25. Hard tissues. 
 Drawer 26. Miscellaneous. 
 
158 A MANUAL OF 
 
 H. 
 ACOTYLEDONOTJS, OR FLOWERLESS PLANTS. 
 
 Drawers 27 and 28. Reproductive system, including 
 
 capsules, apothecia, spores, &c. 
 Drawer 29. Orders, Musci, Hepaticae, Liclienen. 
 Drawer 30. Fungi. 
 
 Drawers 31, 32, and 33. Orders, Characese, Algae. 
 Drawer 34, Sections of stems and miscellaneous 
 
 objects. 
 
 i. 
 
 MINERAL KINGDOM. 
 
 Drawers 35 and 36. Sections of rocks, gems, &c. 
 Drawer 37. Various crystallizations of salts. 
 Drawer 38. Alkaloids. 
 
 Drawer 39. Special micro- crystals, illustrating micro- 
 chemistry. 
 Drawer 40. Miscellaneous. 
 
 By the above plan any special part of the entire 
 series can be enlarged or condensed without interfering 
 with the whole. Eor instance, suppose the drawer con- 
 taining sections of bones had overgrown its space, the 
 only thing necessary is to add another drawer im- 
 mediately below it, and label it, Drawer 1 b, signifying 
 that is the second or extra drawer in the A series ; this 
 would not clash or be confused with the B series, for that 
 would be Drawer 7 c, which means the second or extra 
 drawer of B series. If a smaller collection is required, 
 two or three drawers can be reduced into one. It is as 
 well to keep a book containing the names of the objects 
 in the cabinet, each in its right position, with the num- 
 ber of duplicates for exchange, &c. Care being taken 
 to make a note against the object when lent out to 
 friends, &c. 
 
MICROSCOPIC MOUNTING. 159 
 
 CHAPTER VII. 
 
 212. THE various processes of examination and 
 investigation that are to be adopted with any 
 object must, of course, depend greatly upon its 
 nature. The examination of its outward form 
 will also vary greatly, from the minute and more 
 critical examination of its various fibres and tissues, 
 if organic ; and the determination of its chemical 
 structures, if inorganic. Experience has told me that 
 for any faithful and accurate investigations, it is 
 advisable not to have many objects at the same time, 
 but to rigidly exclude all but one, or, at the most, 
 two specimens, but bring to bear on these subjects the 
 full powers of the mind, with the use of the most 
 accurate instruments, &c., at the disposal of the 
 student. 
 
 213. The first point to notice in conducting an 
 examination of any unknown substance is to test 
 whether organic, inorganic, or combination of the two. 
 This is done by the action of heat. It is best to use 
 the spirit lamp, as the deposit of carbon from the 
 flame of gas greatly interferes with the examination. 
 A piece of platinum foil is placed on the triangle 
 (Pig. 20). The object is then placed on this, and 
 held over the flame of the spirit lamp, when, if the 
 
160 A MANUAL OF 
 
 substance is of an entirely organic nature it turns 
 black, and if held long enough burns entirely away. 
 If it is composed of inorganic and organic substances 
 combined, as in a piece of wheat straw, it first becomes 
 black, but in process of time a white ash is procured, 
 which, however long the platinum is held over the 
 spirit-lamp, still remains the same. This white ash is 
 silica or flint, which has been deposited in the tissues 
 of the plant whilst growing ; but if the substance had 
 been entirely inorganic, it would not have turned 
 black or burnt away, but have remained the same, 
 with the exception of crystals, which fuse and melt, 
 but burn not away; and compounds of ammonia, 
 which entirely sublime. As a type then of the 
 three divisions organic organic and inorganic com- 
 bined and inorganic alone we will take the following 
 three substances : Shell-lac, wheat straw, and bichro- 
 mate of potass. Now the wheat straw of course, 
 shows to the unassisted eye its organic nature, but if 
 the shell-lac has been previously tinted to the required 
 tint, it would greatly resemble the bichromate of 
 potass ; but upon subjecting it to the test of heat, or 
 rather burniug, the shell-lac will turn black, and burn 
 entirely away, showing its organic nature ; whilst the 
 bichromate, with the exception of fusing, will remain 
 entirely the same, which is a proof of its inorganic 
 origin. Eor all the common chemical tests see para- 
 graph 215, &c., it is quite necessary that the student 
 should have, at least, a slight knowledge of them ; for, 
 with the microscope, the smallest quantity of any ordi- 
 nary substance can be analysed if proper care is taken. 
 214. If the specimen under examination is proved 
 to be of an organic nature, its further examination is 
 
MICROSCOPIC MOUNTING. 161 
 
 generally conducted with the microscope alone, few 
 re-agents being used; but if of an inorganic nature, 
 chemical tests as well as the microscope are brought to 
 our aid. We will take, for example, wheat flour and 
 powdered chalk. Upon subjecting the flour to the 
 heat test it will be found to turn black, and burn nearly 
 away, proving its organic nature, and leaving only a 
 small amount of silica, &c. We next roughly mount 
 on a glass slip three small quantities of the flour one 
 dry, one in water, one in balsam using for the purpose 
 three \ thin glass circles. We then place that which 
 is mounted in balsam, under the polariscope, using 
 \ inch power. The well-known cross of starch granules 
 will then appear, and as the analyser is turned, will 
 rotate, proving that it is starch. To make quite sure, 
 however, a small drop of the re-agent, solution of iodine, 
 (see Recipe 54, also paragraph 226), is applied to the 
 small quantity of the dry flour, allowed to remain one 
 minute, add a small quantity of water; then place 
 the slide under the \ inch power, when, immediately, 
 the blue colour of the granules will be perceived, 
 proving it to be starch. A better re-agent is iodide 
 of potassium, to which add one drop of sulphuric 
 acid : this liberates the iodine. The polariscope and 
 analyser must be taken off previous to this observation. 
 We have therefore proved the particles of matter to be 
 starch. Their shape and size will generally prove 
 what kind. To observe their shape the granules that 
 have been mounted in water must now be brought 
 under examination, and by their globular character 
 are proved to be wheat starch (see Fig. 123, plate 11). 
 Upon testing the powdered chalk with heat, its inor- 
 ganic character is immediately discovered, for though 
 
 M 
 
162 A MANUAL OF 
 
 consisting of minute shells, the remains of f oraminifera 
 (see Chapter V., paragraph 113) ; these shells consist 
 entirely of carbonate of lime, an inorganic compound. 
 We proceed in testing as with the flour. Roughly 
 mount three small quantities one dry, one in water, 
 one in balsam or dammar using thin glass circles as 
 before. Taking that which has been mounted in balsam, 
 we place it under the polariscope, as in the case with 
 flour, but, unlike that substance, it will be found to 
 polarise scarcely at all, but we notice instead traces of 
 various organisms ; therefore, to get a clearer view of 
 these, we observe it without the polariscope and 
 analyser, and under the J inch power many entire 
 shells of f oraminifera are seen, proving its former 
 organic character. We next take the part that has 
 been roughly mounted in water, to this we add one 
 drop of sulphuric acid (SO 2 Ho 2 ), using for this 
 purpose one of the re-agent drop bottles, Fig. 12. The 
 action of this acid upon the shells must be observed, as 
 it proves that they consist of carbonate of lime, the 
 sulphuric acid disengaging the carbonic acid gas, 
 which will be seen escaping in minute bubbles, and 
 forming with the lime another compound, i.e. sulphate 
 of lime (SO 2 Cao"), the presence of which is proved 
 by the needle-like crystals, see Pig. 137, plate 11. To 
 make quite sure that it is a carbonate of lime, we add 
 to the part that has been roughly mounted dry, one 
 drop of hydrochloric acid (HC1), using the same kind 
 of test bottle, Eig. 12. Upon applying the acid, 
 minute bubbles of carbonic acid gas will be seen 
 escaping, causing much effervescence. When they 
 have all escaped, what remains is a new compound 
 viz., chloride of calcium, This is formed from the 
 
MICROSCOPIC MOUNTING. 163 
 
 chlorine of the hydrochloric acid, having united with 
 the lime after the carbonic gas had been set free. To 
 prove the presence of lime, we drop one drop of oxalate 
 of ammonia(C 3 O 3 Amo 3 // ) from one of the test bottles on 
 to the edge of the thin glass cover, allowing it to run 
 into the fluid chloride of calcium, when, immediately 
 a white insoluble deposit of oxalate of lime is formed, 
 again proving the existence of lime. This deposit 
 may be examined under the microscope, and com- 
 pared with Pig. 135, plate 11. Prom the above tests 
 we may now safely conclude that the powder which 
 we have been examining is carbonate of lime in 
 the form of chalk. The above will give an idea 
 of the method of testing an inorganic compound. 
 
 215, For all the tests of the metallic and non- 
 metallic elements, a good work on chemistry must 
 be consulted, as space will not permit of our giving 
 the entire series. But for the use of the student we 
 will now give the characteristic chemical and micro- 
 chemical tests of a few common metallic elements, 
 and two non-metallic, viz : 
 
 Potassium, Gold, 
 
 Sodium, Lead, 
 
 Calcium, Silver, 
 
 Magnesium, Mercury, 
 
 Iron, Iodine, and 
 
 Copper, Silicon. 
 
 216. Potassium. "When bichloride of platinum(PtC! 4 ) 
 is added to a solution of any salt of potassium, to which 
 a few drops of hydrochloric acid have been previously 
 added, a yellow crystalline deposit is formed, which 
 does not polarise light (see Pig. 140, plate 11) ; also 
 
 M 2 
 
164 A MANUAL OF 
 
 if a solution of tartaric acid is added to a solution of 
 a potassium salt, a white crystalline deposit of cream 
 of tartar (hydric-potassic tartrate) is formed. 
 
 217. Sodium. If bichloride of platinum is added to 
 a solution of a sodium salt, to which hydrochloric acid 
 has been previously added, no precipitate or deposit 
 occurs ; but if this solution is evaporated sponta- 
 neously it crystallizes in plates, &c., which polarise 
 light (see Pig. 141, plate 11). By this test sodium 
 may be distinguished from potassium. Another good 
 test is to add carbazotic acid to a solution of soda, 
 when crystals of carbazotate of soda are formed (see 
 Pig. 139, plate 11). But the presence of sodium is 
 best shown by the yellow band in the spectrum. 
 
 218. Calcium. As mentioned before, when oxalate 
 of ammonia (C 2 O 3 Amo 3 // ) is added to a solution of a 
 calcium salt, an insoluble (in water) deposit of 
 oxalate of lime is formed ; if the lime exists only in a 
 nearly insoluble compound, as in the case of chalk, it 
 must be dissolved by the action of an acid, and then 
 tested with the oxalate of ammonia, the oxalate 
 of lime may then be compared with Pig. 135, plate 11. 
 
 219. Magnesium. If phosphate of soda (POHoNao 3 ) 
 together with a small quantity of liquor ammonia 
 is added to a solution of a magnesium salt, a white 
 deposit of ammonic magnesic phosphate (POMgo^Amo) 
 is formed, which compare with the drawing (Pig. 138, 
 plate 11). If the magnesia is present as an oxide, 
 carbonate, &c., it must be dissolved in an acid 
 previous to testing. 
 
 220. Iron. The best test is the formation of Turn- 
 bull's blue, or Prussian blue, according to whether the 
 solution of a salt of iron (which should be rendered 
 
MICROSCOPIC MOUNTING. 165 
 
 acid by a drop or two of hydrochloric acid) is a 
 negative or positive salt. The reaction is as follows : 
 Negative salt of iron. Potassic ferricyanide causes a 
 dark blue precipitate of ferrous ferricyanide 
 (Fe 3 Fe 2 Cy 12 ), known as Turnbull's blue; it is decom- 
 posed by potassic hydrate (solution of potass) . Positive 
 salt of iron. Potassic ferrocyanide causes a dark 
 precipitate, or deposit of ferric ferrocyanide blue 
 (Ee 2 iv (EeCy 6 ) iv 2 ), called Prussian blue; this is also 
 decomposed by potassic hydrate. In testing for these 
 and other precipitates, it is best to use my precipita- 
 ting cell, shown at Eig. 142. If iron is thought to be 
 present as an ore, or in small particles as a manu- 
 factured and prepared metal, it must be dissolved in 
 hydrochloric acid (HC1) with a slight excess of 
 acid. 
 
 221. Copper. The colour of the solutions of salts 
 of copper is blue or green. Liquor ammonia 
 (ammonic hydrate) causes a black precipitate ; but 
 when in excess it redissolves this, forming a beautiful 
 dark blue solution, quite characteristic of copper. A 
 piece of bright iron wire, when placed in a solution 
 of a salt of copper, rendered slightly acid, becomes 
 coated with red metallic copper. If copper is thought 
 to be present either as an ore or metal, it must be dis- 
 solved by the action of sulphuric acid (S0 2 Ho 2 ). 
 
 222. Gold. When a solution of any salt of gold is 
 acted upon by a solution of oxalic acid (C 2 O 2 Ho 3 ), 
 gold is precipitated in the metallic state. A bar or 
 small piece of tin also causes a precipitate of the 
 so-called purple of cassius. A solution of proto- 
 chloride of tin will also give a purple brown precipi- 
 tate. If gold is thought to be present in the form of 
 
166 A MANUAL OF 
 
 gold dust, &c., it must be dissolved in aqua regia 
 previous to using these tests. 
 
 223. Lead. Iodide of potassium, when added to a 
 solution of a lead salt, gives a bright yellow precipi- 
 tate of iodide of lead (PbI 3 ), which dissolves in boil- 
 ing water. Potassic chromate (CrO 3 Ko 3 ); also causes a 
 yellow precipitate of the yellow chromate of lead 
 (Cr0 3 Pbo // ). If lead is thought to be present as an 
 ore or oxide, it must be dissolved in nitric acid 
 (NO 3 Ho) previous to using the above tests. 
 
 224. Silver. Hydrochloric acid, when added to a 
 solution of a salt of silver, precipitates the white curdy 
 chloride of silver, (AgCl) which is soluble in liquor 
 ammonia (ammonic hydrate). If silver is thought to 
 be present in the form of an ore, &c., it must be dis- 
 solved in nitric acid previous to using the above 
 test. 
 
 225. Mercury. If liquor potass (potassic hydrate) 
 is added to a salt of mercury, to which nitric acid 
 (NO 3 Ho) has been added, a red precipitate of the red 
 oxide of mercury (HgO) is obtained. If this is col- 
 lected in a very small test tube, and subjected to heat 
 of spirit-lamp, the oxygen is driven off, and small 
 globules of pure mercury will be formed in the 
 upper part of the tube. Mercury may also be distin- 
 guished by placing a small piece of copper wire or 
 foil in a solution of a salt of mercury, when it 
 becomes coated with a. white copper amalgam. The 
 piece of wire must then be placed in a dry test-tube, 
 and subjected to heat, when globules of pure mercury 
 will be found in the tube. If mercury is supposed to 
 be present in a powder, &c., it must be dissolved in 
 nitric acid (NO 2 Ho) previous to using the above tests. 
 
MICROSCOPIC MOUNTING. 167 
 
 226. Iodine. The best test for free iodine is starch, 
 which turns blue when brought into contact with it. 
 If the iodine exists in the form of an iodide, it is best 
 to liberate the iodine by the addition of a few drops 
 of hydrochloric acid (HC1) ; it will then exhibit its 
 characteristic reaction with the starch. It may also 
 be known by its beautiful violet vapour which it 
 gives off when heat is applied. 
 
 227. Silicon generally exists in the form of silica, 
 which is not acted upon by acids, with the exception 
 of hydrofluoric acid ; but it dissolves when fused in 
 carbonates of soda and potass, &c., which I have 
 taken advantage of in separating foraminifera (see 
 Chapter V., paragraph 135). When testing, to be 
 quite sure that silica has been dissolved in the carbon- 
 ate of potass, hydrochloric acid must be added gradually 
 until jelly-like flakes of silicic acid appear. In testing 
 for this and small quantities of all other chemical 
 compounds, &c., it will be found best to use a precipi- 
 tating cell like Fig. 142. 
 
 These tests have only been added as a guide to 
 the student, and not in any way to supplement 
 reference to other works of a strictly chemical 
 character. 
 
 228. Carbonates. In testing for carbonates, if the 
 substance is of an earthy nature, nitric acid (NO 2 Ho) 
 must be applied ; when, if it consists of any carbon- 
 ates (for instance, chalk, carbonate of lime), the lime 
 will be dissolved, and bubbles of carbonic gas will be 
 set free, which are easily seen escaping when the cell 
 is placed under the microscope, If the carbonate to 
 be tested is in the form of a solution of a salt like 
 carbonate of soda, a small drop of chloride of calcium 
 
168 A MANUAL OF 
 
 (GaCl 3 ) must be applied, when immediately carbonate 
 of lime is formed (see Pig. 134, plate 11.) 
 
 229. Sulphates are best distinguished by adding to 
 their solution a small quantity of nitrate of barium, 
 when a white deposit or precipitate of sulphate of 
 barium is formed, proving the presence of a sulphate. 
 This deposit is nearly insoluble in acids. 
 
 230. Chlorides, when in solution, are easily dis- 
 tinguished by adding a drop of nitrate of silver, 
 when immediately a white curdy precipitate of 
 chloride of silver (AgCl) is produced, insoluble in 
 nitric acid, but soluble in liquor ammonia (ammonic 
 hydrate). 
 
 231. Phosphates, when in solution, may be dis- 
 tinguished by adding ammonia and then a few drops 
 of a solution of sulphate of magnesia, when character- 
 istic crystals of ammonic phosphate of magnesia will 
 be formed (see Pig. 138, plate 11). 
 
 232. Having thus givena slight sketch of the methods 
 of examination of inorganic substances, I cannot leave 
 the subject without noticing the usefulness of electricity 
 when applied to the microscope. By the kindness of 
 Mr. Philip Braham, of Bath, and Mr. Hardwicke, I am 
 enabled to give an extract from an article contributed 
 by him to the "Microscopical Journal." "The 
 instrument used I give a sketch of (see plate 9), and 
 the electrical stage (a diminutive double discharger, 
 which does excellently for spectrum analysis in con- 
 nection with an induction coil), and galvanic battery, 
 with fittings for varying the quantity and intensity 
 of the electric current. The sketch of the discharger 
 shows the manner in which it is fitted. The two 
 short pillars, A, A, are of ivory, turned to a cup- shape 
 
Maiittaiof Microscopic moimtiri^. PI. I 
 
 Spring Cbup 
 
 Hlmllln 
 
MICROSCOPIC MOUNTING. 169 
 
 on the top to fit the balls ; the springs, B, B, keep the 
 balls in their place, and are fastened to the side of the 
 ivory pillars by the binding screws, c, c, to which the 
 wires from the poles of the battery are connected; 
 the ends of the discharger rods are split to receive the 
 short wires of the metal under electrolysis. 
 
 " The battery is similar in its construction to 
 Snaee's, but with carbon plates instead of platinized 
 silver; and, excited with bichromate of potass and 
 sulphuric acid, it has the advantage of not evolving 
 fumes or acid spray. The wheel at the end, D, is 
 provided with a break, E, to keep the plates at any 
 required depth in the solution. The spring clip, G, 
 connects any number in the series of six cells. 
 
 " When it is desired to examine the crystals of metal 
 in solution of its neutral metallic salts, gold, silver, 
 copper, lead, tin, and zinc, being the best, a drop 
 must be placed on a glass slip and the ends of the 
 wires fitted into the discharger rods dipped into it, 
 and kept about a tenth of an inch apart (see plate 9, 
 Discharger,), lowering the battery into the solution, 
 and carefully watching the terminal in connection with 
 the zinc pole," practice will give the right degree. 
 Quantity i.e., depth of plates in solution and in- 
 tensity i.e., number of cells. 
 
 A rectangular prism is adapted to the body of the 
 microscope to save fatigue in long- continued observa- 
 tions, and by turning on its optic centre enables many 
 persons to see the same objects by turning the eye- 
 piece towards them. The light must be entirely 
 reflected by placing coloured glass in the place of the 
 sub stage diaphragm, and sending light through it. A 
 clear outline is given to the metallic crystals and the 
 
170 A MANUAL Or 
 
 beauty of the effect enhanced. Chloride of barium, 
 chloride of sodium, chloride of potassium, ferricyanide 
 of potassium, bichromate of potass, &c., form well on 
 the positive electrode. 
 
 233. The following re-agents are used in the exami- 
 nation of both organic and inorganic substances. All 
 of them should be kept in the small test-bottles (see 
 Fig. 12): 
 
 Sulphuric acid. 
 
 Nitric acid. 
 
 Hydrochloric acid. 
 
 Acetic acid. 
 
 Chromic acid. 
 
 Carbazotic acid. 
 
 Nitrate of barium. 
 
 Nitrate of silver. 
 
 Oxalate of ammonia. 
 
 Iodine (solutions of), see Recipe 54. 
 
 Ammonia (liquor). 
 
 Solution of potass. 
 
 Solution of soda. 
 
 Ether. 
 
 Alcohol. 
 
 Tests-papers, &c. 
 
 234. Sulphuric acid. The pure acid must be used. 
 When it is added to the cells of plants previously dyed 
 with iodine, it renders the cell- wall (cellulose) blue or 
 purple. It causes epidermal tissues to swell up and 
 also separates the cells; and as a test for lime, see 
 paragraph 214. 
 
 235. Nitric acid, when pure, dissolves all but cellu- 
 lose and silica when vegetable substances are boiled in 
 it, also used for cleaning diatoms (see paragraph 127). 
 
MICROSCOPIC MOUNTING. 171 
 
 Colours albumen yellow, and then dissolves it. When 
 20 parts are diluted with 100 parts water, it coagulates 
 albumen, and also renders muscular fibre cells better 
 for examination. 
 
 236. Hydrochloric acid is chiefly used for dissolving 
 out the inorganic compounds in bone, teeth, &c. It 
 is also used for dissolving any substance suspected to 
 be lime, previous to applying the proper tests (see 
 paragraph 218). 
 
 237. Acetic acid. Has the property of dissolving 
 albuminous granular matter. It renders preparations 
 that have been hardened in alcohol transparent, 
 especially if boiled in it. It is also useful for testing 
 phosphate and carbonate of lime, which it dissolves, 
 whilst it does not in the least affect oxalate of lime. 
 This is a useful test for raphides (see paragraph 144). 
 
 238. Chromic acid. This, when much diluted, is 
 used for the hardening of tissues. Eor its preparation, 
 &c. see Recipe 18. 
 
 239. Carbazotic acid is chiefly used for testing for 
 soda (see paragraph 217). 
 
 240. Nitrate of barium used for testing the presence 
 of sulphates (see paragraph 229). 
 
 241. Nitrate of silver used for testing for chlorides 
 (see paragraph 230). It is also used for staining 
 tissues (see paragraph 150), and it gives a yellow 
 precipitate with phosphates. 
 
 242. Oxalate of ammonia, forming oxalate of lime, 
 is used for testing for lime (see paragraph 218), which 
 dissolves in the strong mineral acids, such as sulphuric, 
 but not in acetic acid. 
 
 243. Iodine (solutions of) (see Recipe 54) is some- 
 times used for dyeing transparent vegetable and 
 
172 A MANUAL OP 
 
 animal tissues, so as to render them distinct ; but it is 
 chiefly used as a test for starch, which it colours blue 
 (see paragraph 226). 
 
 244. Liquor ammonia. Dissolves chloride of silver 
 (see paragraph 224) ; also much used for preparing the 
 staining fluids, &c., extracting grease, &c. Ammoniac 
 oxide of copper dissolves delicate cellulose, but does 
 not attack woody fibre, &c. 
 
 245. Solution of potass does not much affect veget- 
 able structures, but it dissolves nearly all animal 
 substances, with the exception of chitine. Its action 
 is much stronger when heated ; it separates many 
 animal substances, such as bone, nails, &c., into their 
 component cells, &c. It is also used in the prepara- 
 tion of insects. 
 
 246. Solution of soda. This acts in nearly the 
 same way as the potass, and some persons prefer it. 
 
 247. Ether is geneally used as a re-agent for proving 
 the presence of fatty or resinous matter, which it dis- 
 solves. It also dissolves animal and vegetable colour- 
 ing matters. It may be known by its smell. 
 
 248. Alcohol is much used for its preservative pro- 
 perties. It dissolves resinous matter, and vegetable 
 and animal colouring matters, &c. 
 
 249. Test papers, fyc. It is as well to keep both the 
 red and the blue litmus paper. The red turns blue if 
 there is any trace of alkali in the fluid under examina- 
 tion, and if any acid the blue paper turns red. The 
 fluid is then subjected to further examination (see 
 paragraphs 215, 216, &c). 
 
 250. I must now give a slight sketch of the method 
 of examination of organic substances. If large, as in 
 the case of an insect, their correct name is, of course, 
 
Plate 10. ADULTERATIONS OF FOOD, &.C. 
 
 
 
 
 *s4$o^ 
 
 To 
 SO *zZ 
 
 % 
 
 ^s 
 
 #;l# 
 
 MS 
 
 jte*. 
 
 ^,,, v , >.- JT"."0^ 0( -". c Ci~A..^tf ^^^^^ 
 
 c- 
 
 - 
 
 ' 
 
 
 
 found/ advisable 
 
 plate wi,dv a^ pocket 
 
MICROSCOPIC MOUNTING. 
 
 173 
 
 gained by reference to suitable books ; but if there 
 remains only a small particle of matter it is much 
 more difficult. The following is a general outline; 
 Make a note of the form and colour. Note the effect 
 of polarized, reflected, and transmitted light. In the 
 case of shells or any rolling bodies ; mount a very 
 small quantity in hard balsam, and then grind the 
 surface, this will go far to prove their exact form. If 
 the object is soft examine it by pressure, using the 
 compressorium, Pig. 37. If possible, divide into ten 
 or twelve parts, and note the action of the re-agents 
 upon it; if very thick or hard, grind it until the section 
 is transparent, taking a small piece from the whole for 
 this purpose. If softer, cut sections with razor or 
 scalpel, subjecting these 
 sections to the action of 
 the re-agents. If very 
 minute, like dust, in- 
 crease the power of the 
 microscope until the shape 
 of the object can clearly 
 be made out, still noticing 
 the action of the re-agents. 
 In examining deposits 
 always use the pipette (see 
 Pig. 119). When the re- 
 agents are applied always 
 use my cell (see Pig. 142). Fig. 119. 
 
 If the objects under examination are placed in fluid, 
 the air-bubbles must not mislead the student (see Pig. 
 120), as they might do if he had not previously noticed 
 the appearance of them when in water or oil ; also note 
 the difference of oil globules in water. If the object 
 
174 A MANUAL OF 
 
 \ 
 
 under examination is alive, and it is desired to keep it 
 moist, a little apparatus, like Pig. 121, 
 must be used ; it consists of a small 
 piece of glass tubing fixed with cement 
 to a slide, a piece of thin glass nearly 
 covers this little reservoir of water: 
 a fine thread of cotton or wool is 
 then placed between the object under 
 examination and the reservoir, this serves to conduct 
 
 the water to the object. Always 
 make rough sketches of the 
 object under examination, do 
 Flgi 121> this with the aid of the camera 
 
 lucida, Fig. 34. "When it is desirous to apply heat 
 to the object the best plan is one by H. Strieker : a 
 piece of tinfoil is cut to the form of a picture- frame, 
 having two arms projecting from opposite sides, this 
 is gummed to the centre of a glass slip, and when it is 
 required to heat any object it must be placed in the 
 centre of the tinfoil frame, and connect the two pro- 
 jecting ends with the poles of a battery (see Plate 9). 
 When the object will be heated, some persons mount 
 a small thermometer nearly the centre of the glass 
 slide, so that the degree of heat may be regulated, 
 (see also Pig. 46, paragraph 42.) 
 
 Both polarized light and the dark field illumination 
 show the relative density or degrees of opacity in the 
 object. Polarized light especially shows secondary 
 deposit in vegetable structures. All investigations 
 should be conducted if possible by daylight. 
 
 251. In noticing the adulterations of fabrics, special 
 attention should be given to the action of the re-agents, 
 as well as the general microscopical character of the 
 
PLATE 11. 
 
 Fro. 12o. FIG. 121*. 
 
 FIG. 130. 
 
 FIG. 131. 
 Human hair Wool x 100. Cotton x 200. Hemp x 100. 
 
 rVf 
 
 FIG. 134. FIG. 135. FIG. 136. FIG. 137. 
 
 Carbonate of Lime x 100. Oxalatc of Lime x 400. Phosphate of Lime x 100. Sulphate of Lime x 100. 
 
 FIG. 138. 
 
 Aminonio- Phosphate 
 of Magnesia x 100, 
 
 . 139. FIG. 140. 
 
 Carbazotate of Soda Bichloride of Platinum 
 
 x W. ami Pottassiviin x 200. 
 
 FIG. 141. 
 
 Bichloride of Platinum 
 and Sodium x dO. 
 
MICROSCOPIC MOUNTING. 175 
 
 fibres ; for instance, silk will dissolve in hydrochloric 
 acid, but wool, cotton, hemp, &c., will be left intact, 
 and both wool and silk dissolve in a strong solution of 
 potass or soda, especially if used at boiling point, but 
 cotton remains nearly entire. Por the microscopical 
 characters of the common fibres, I must refer the 
 student to Pigs. 129, 130, 131, 132, 133, Plate, 11. 
 
 252. Pepper is often largely adulterated with 
 starches, such as wheat, rice, pea, &c., for the micro- 
 scopical characters of which see Plate 11. It is also 
 adulterated with linseed-meal, ground mustard seeds, 
 &c. ; for the microscopical characters of which see 
 Pig. 104, Plate 10, Pig. 103 being ground black 
 pepper unadulterated. 
 
 253. Cayenne pepper is improperly so called, as it is 
 made (or at least it ought to be) from a plant called 
 Capsicum annuum, which belongs to quite a different 
 natural order from the peppers ; it is often largely 
 adulterated with ground rice, deal saw-dust, salt, &c., 
 also with red-lead, vermilion (protosulphide of mer- 
 cury), Venetian red, &c. In testing for these in- 
 organic compounds the cayenne pepper must be in- 
 cinerated or burnt to an ash upon the platinum foil, 
 using the triangle, Pig. 20 : the ash may then be 
 tested for lead, &c. (see paragraph 223). Pig. 105 
 shows the unadulterated, and Pig. 106 the adulterated 
 cayenne pepper. 
 
 254. Mustard is nearly, if not always, largely 
 adulterated with wheat flour, or starch, and turmeric. 
 The wheat starch and turmeric may chiefly be dis- 
 tinguished by their microscopical characters (see Pig. 
 123, Plate 11), and by the application of iodine, when 
 the granules and cells become a deep blue, or apply 
 
176 A MANUAL OF 
 
 solution of potass when they are changed to a reddish 
 colour. Eig. 107 represents the microscopical appear- 
 ance of pure mustard, and Pig. 108 the adulterated. 
 
 255. Coffee is even now largely adulterated with 
 chicory, roasted wheat, and potato starch, mangel- 
 wurzel, acorns, &c. Eig. 109 shows a pure sample, 
 and Eig. 110 an adulterated coffee (ground). 
 
 256. Chicory is also adulterated with roasted starches 
 mangelwurzel, saw dust, &c. Eig. Ill is a drawing 
 from the pure article, Eig. 112 the adulterated. 
 
 257. Tea is adulterated with other leaves, such as 
 sycamore, elm, willow, horse-chestnut, heech, plum, 
 &c., and also with Prussian blue (Eerrocyanide of 
 iron), plumbago, turmeric, chrome yellow (chromate 
 of lead), &c. To test the leaves for their adulteration 
 with any inorganic substance, the leaves must be burnt 
 on the platinum in the same way as recommended for 
 cayenne pepper. To obtain cuticles for comparison 
 see paragraph 125. Eig. 113 is pure tea, and Eig. 114 
 a sample of the adulterated article. 
 
 258. Tobacco is adulterated with dock, rhubarb, 
 coltsfoot, potato, and other leaves, especially British. 
 It is also adulterated with sugar, salt, &c., to add to 
 its weight. The tests will be chiefly performed with 
 the microscope, as the adulterations are of an organic 
 nature. Eig. 115 is a drawing of a pure sample of 
 tobacco, and Eig. 116 the adulterated article. 
 
 259. Cocoa is adulterated with potato, arrowroot, 
 wheat, maize, sago, and other starches, and with sugar, 
 chicory ; also with Venetian red, red ochre, and other 
 earths. To test for the inorganic compounds present 
 (if any), it must be burnt to an ash on the plati- 
 num foil, as recommended for cayenne. Eig. 117 is 
 
MICROSCOPIC MOUNTING. 177 
 
 unadulterated cocoa, and Fig. 118 the adulterated 
 article. 
 
 259. Before testing or examining an adulterated 
 article, a slide of the pure substance should be 
 mounted for constant reference; also slides of the 
 articles used in its adulteration. 
 
 260. When an ash has been obtained by burning 
 the substance upon platinum foil (or mica), it should 
 be divided into ten or twelve parts, and each part 
 examined separately, using the precipitating cell (Eig. 
 142), and noticing the action of the re-agents and 
 tests. 
 
 FIG. 142. 
 
 261. Drawing. As I mentioned before, it is quite 
 necessary for the student to make sketches of all the 
 objects that come under his observation. In doing 
 this he should use a low power at first, and gradually 
 increase it (if necessary) as his eyes and powers of 
 observation become accustomed to the work. Hand- 
 made drawing paper will be found better than 
 machine-made, especially if the student tints his 
 drawings with water-colours afterwards. If he 
 desires to multiply his original sketches for the 
 benefit of friends and others, a good way of doing so 
 is by the electrical printing machine by Waterlow 
 and Co., the chief fault against the process being that 
 
 N 
 
178 A MANUAL OF 
 
 the reproductions are in blue. The amateur student 
 will also find the transfer lithographic paper, called 
 the Autographic paper, sold by Maclure, Macdonald, 
 and Co,, very useful, that is if he desires to have his 
 drawings printed. When making a sketch of the 
 object under observation, the outline should be drawn 
 with the aid of the camera lucida (see Pig. 34), and 
 all the minuter details put in afterwards by a constant 
 reference to the microscope. If possible, the objects 
 should always be drawn to scale. To make this 
 easier, the paper must always be exactly ten inches 
 from the camera lucida (see Pig. 34), an eyepiece 
 micrometer used, and the lines throw T n by this instru- 
 ment on to the paper, noted, and a scale of the dis- 
 tances between each line marked for future reference. 
 Scales of the different powers may easily be made 
 by this plan, and will be found very useful. In 
 making drawings by artificial light, two lamps should 
 always be used, one near the mirror to illuminate the 
 object, and the other close to the paper upon which 
 the student is making his sketch. 
 
 262. This piece of apparatus which I have lately 
 invented to separate various species of Poraminifera 
 from sand and other extraneous bodies can be easily 
 made, and used. Take a piece of wood about 6 inches 
 long, by 2^ inches wide, and -J inch thick, also another 
 piece 1 inch square, 6 inches long; glue or cement, this 
 in the centre of the larger piece, when dry, make a 
 triangular groove down the centre of this slip. Now 
 cut two pieces of glass 8 or 9 inches long by 1^ inch 
 wide, also a triangular piece 1-J- inch long and 1 inch 
 wide at the base of the triangle; cement these together 
 as shown in the drawing (Pig. 143), using the cement, 
 
MICROSCOPIC MOUNTING. 179 
 
 Recipe 6 ; fix this into the triangular groove made in 
 the centre of the wood slip. Its use I think will be 
 apparent. Place it flat on a table, put about a tea- 
 spoonful of the Foraminiferous sand in the upper end 
 of the trough, then direct a gentle but constant stream 
 of water from the wash bottle (Pig. 13, paragraph 10), 
 allowing the waste water to flow into a beaker or any 
 other vessel that may be handy (see drawing). In 
 course of time, the foraminifera will lie found separated 
 according to their several specific gravities, more es- 
 pecially if the trough is made rather longer than this ; 
 it is therefore advisable to have about 3 troughs of 
 
 FIG. 143. 
 
 different lengths. One great thing to be remembered 
 is that a gentle stream of water be directed upon the 
 sand, &c., for if too strong a flow is made, the result 
 will not be good; in this case it is time, and not force 
 that gives the result. 
 
 N.B. The waste water that comes off should be 
 allowed to precipitate any matter that it may contain, 
 for in some cases valuable diatoms, fyc., may come 
 away, they being of lower specific gravity ; therefore 
 examine before getting rid of the deposit. 
 
 N 2 
 
180 A MANUAL OF 
 
 263. In the current number of the Journal of the 
 Franklin Institute, Mr. D. S. Holman gives the 
 following account of his new form of live slide : 
 In the use of the microscope in that branch of science 
 called biology, it is often desirable to keep under view 
 small organisms, such as bacteria and vibriones, for 
 hours, and even for days and weeks at a time. Hitherto 
 this has not been possible, for lack of a proper contri- 
 vance; the animals would soon die from the exhaustion 
 of oxygen in the confined space, and they were not in 
 that normal condition necessary for satisfactory study 
 during the time that they did live. Below is pictured 
 what is known as Holman' s Life Slide, which obviates 
 this difficulty. The construction of this accessory to 
 the microscope may be described as follows : In the 
 centre of one face of a strip of glass 3 inches long, 
 lyg- inches wide, and -f$ of an inch thick, are ground 
 two very shallow cavities, side by side, oval in form, 
 
 and with their length in the direction of the length of 
 the slide ; a straight shallow groove extends between, 
 and a little beyond them at each end ; through the 
 centre of these cavities, and at right angles to their 
 long diameter, but not so long as to reach their sides, 
 
MICROSCOPIC MOUNTING. 181 
 
 a cavity is ground as deep as the thickness of the glass 
 will permit. 
 
 The cavities and groove thus described, occupy a cir- 
 cular surface of the slide about f of an inch in 
 diameter, which is covered, when in use, with a circular 
 piece of microscopic glass 1 inch in diameter. 
 
 The philosophy of its action may be thus described : 
 Into the deep cavity, as a reservoir, is put the 
 material in which are the organisms to be examined ; 
 the cover is then put on, and the fluid on the surface 
 of the plate wiped away. The pressure of the atmos- 
 phere holds the thin cover firmly to the plate, and the 
 fluid between the cover and the plate commences to 
 evaporate at the edges, its place being supplied by 
 more fluid from the reservoir. As the evaporation 
 proceeds, the cover is bent downwards by the atmos- 
 pheric pressure, and meets a resistance at the junction 
 of the groove with the edge of the shallow cavities, 
 resulting in the edges of the cover rising at each end 
 of the long groove, and a small bubble of air finds its 
 way through the groove to the reservoir. This auto- 
 matic action thus furnishes a continual supply of fresh 
 air, and the life of the little animals is sustained 
 during the time necessary to observe the changes 
 that take place in them during their life history. When 
 the smaller forms are inclosed in one of these life 
 slides, to get access to the air, they seek the edges of 
 the cover, and range themselves in a zone, at a short 
 distance from its rim, close to where the air comes in 
 contact with the water. Being thus situated, in accor- 
 dance with the law that compels them to take up these 
 positions, they can be viewed with the highest powers 
 of the microscope, and their true nature and habits 
 
182 A MANUAL OF 
 
 much better studied than by the old methods. This 
 slide was first described in the ENGLISH MECHANIC, 
 Vol. XVI., p. 138, but is now presented in a much 
 improved form. 
 
MICROSCOPIC MOUNTING. 183 
 
 APPENDIX. 
 
 VARIOUS USEFUL RECIPES, &C. 
 
 MOST of the following recipes are mentioned in the 
 preceding chapters, but they are here given in full: 
 
 1. Chloroform 2 ounces. 
 Gutta-percha ^ ounce. 
 Tallow 1 drachm. 
 
 Dissolve and mix. To be used for any purpose that 
 requires a substance that never gets hard (see para- 
 graph 66). 
 
 2. Eesin 1J ounces. 
 Beeswax J ounce. 
 Tallow 1 drachm- 
 Oil-colour any tint, colour, or shade. 
 
 Melt and mix. Keep in small salve boxes ; or it may 
 be kept in the small moist-colour pans used by artists. 
 It is best to keep a stock of various tints, as it saves 
 time when mounting many variously-coloured natural 
 objects, such as lichens, seeds, mosses, &c. When 
 wanted for use it must be dissolved by the action of 
 heat. The heat from a water or sand-bath is best. 
 
184 A MANUAL OF 
 
 3. Solution of gum (thick), 1 ounce. 
 Glycerine, J ounce. 
 Camphor, 4 or 5 grains, 
 
 It is as well to add 1 grain of arsenious acid. 
 
 Keep it in a corked, not stoppered bottle. This will he 
 found very useful for many objects, more especially 
 where quick mounting is required, as it does not re- 
 quire any heat. It is better adapted for minute insect 
 than vegetable objects, as in the latter it often causes 
 rupture of the primordial utricle or cell-wall. 
 
 4. Gutta-percha, finely cut, J ounce. 
 Turpentine, 4 ounces. 
 
 Dissolve with heat, and add shell-lac, ounce. 
 
 Dissolve with heat. The heat must be continued 
 until a drop let fall upon a slip of glass becomes 
 nearly hard when cool. Care must be taken in the 
 preparation of this cement, on account of the in- 
 flammable nature of turpentine. This is cheap, and 
 will meet all the requirements of a general cement for 
 fixing many cells, &c. 
 
 5. Caoutchouc, cut small, ^ ounce. 
 Mineral naphtha, 1 pint. 
 
 Dissolve with heat, and add shell-lac -J ounce. A 
 smaller quantity of naphtha than this may be used, but 
 using the larger quantity will be found the quickest. 
 This cement is very useful, but it is chiefly used in 
 making and sealing cells (see Chapters II., IV., &c.); 
 if required it may be bought at most of the opticians, 
 &c., under the name of caoutchouc cement. Use 
 caution in making. 
 
MICKOSCOPIC MOUNTING. 185 
 
 6. Resin, 2^ ounces. 
 Beeswax, -J ounce. 
 Canada balsam, 1 drachm. 
 
 Dissolve with heat and mix. "When wanted for use, it 
 must also be rendered mouldable by the action of 
 heat. It is a strong cement, and may be used for 
 fixing cells to glass, &c. 
 
 7. Powdered sealing wax. 
 
 Cover with methylated spirit and dissolve with a 
 gentle heat. Often used for finishing circles, cells, 
 &c. ; but Berlin black is much better. 
 
 8. Gum Arabic, 2 ounces. 
 "Water, 2 ounces. 
 
 Dissolve gradually and add 
 
 Soaked gelatine, % ounce. 
 Glycerine, 30 drops. 
 Lump of camphor. 
 
 Dissolve the gelatine in the gum water by the action 
 of heat, and add the glycerine and camphor. Con- 
 tinue the action of the heat for a short time, and leave 
 the lump of camphor constantly in the solution. This 
 gum- water will be found the strongest and best for 
 use, as it will not chip when placed on glass, &c. It 
 may therefore be used for labels and other purposes 
 where a strong gum is required. 
 
 9. Colloid silica, or silicic acid (SiHo 4 ) is made by 
 adding 
 
 Silicate of potass, 1 drachm. 
 
 Water, 2 ounces. 
 
 Mix and pour into a glass vessel, and gradually add 
 
186 A MANUAL OF 
 
 hydrochloric acid (HC1) in drops until flocculent films 
 slightly appear; then pour into a dialysing drum, 
 which place in a hasin of pure water. The chloride 
 of potass formed by the action of the hydrochloric 
 acid on the potass will then pass into the water in the 
 basin, leaving the silica in the form of colloid silica, 
 or silicic acid (SiHo 4 ) in the dialysing drum. It is 
 better if the water in the basin is renewed in the 
 course of every three or four hours. To obtain the 
 silica quite pure it is better to subject it to this pro- 
 cess for at least three or four days. When various 
 crystals, such as sulphate of copper, chlorate of 
 potass, boracic acid, &c., are dissolved in this fluid 
 and evaporated on a glass slide, most remarkable 
 and interesting forms appear, and a large field of in- 
 vestigation is opened by its use (see Chapter III.). 
 
 10. A saturated solution of bichloride of mercury 
 (HgCL corrosive sublimate) is very useful in render- 
 ing the bodies and cilia of the infusoria more distinct. 
 It is also used for the same purpose with nearly all 
 proteine compounds. 
 
 11. Lamp-black. 
 
 Gold size. 
 
 Mix well in a mortar. Makes a good black varnish 
 for finishing slides and other purposes where a tough 
 varnish is required. 
 
 12. Chloride of calcium (CaCL) is a good preserva- 
 tive fluid for many things (see Chapter IV.), it is 
 often difficult to obtain at country chemists, but may 
 be easily made by dissolving chalk in hydrochloric 
 acid until the effervescence ceases, when the water 
 may be driven off by evaporation, and the crystals 
 that form may be taken out and put into a clean bottle 
 
MICROSCOPIC MOUNTING. 187 
 
 and sufficient distilled water added to make a saturated 
 solution, which keep in stoppered bottle. A small 
 quantity may also be kept in a drop-bottle to be used 
 as a re-agent. 
 
 13. Canada balsam dried in a cool oven until it 
 becomes of a pasty nature, and then dissolved in 
 chloroform, benzole, ether, &c., is often much better 
 to use than the balsam when undiluted. Camphor is 
 also mixed with it when it has been brought to this 
 pasty state, and by its action the balsam is again 
 rendered fluid. Many persons prefer this plan to any 
 other. 
 
 14. Boracic acid (BHo 3 ), made by adding hydro- 
 chloric acid (HC1) to a hot saturated solution of borax 
 (B 4 O 5 Nao 2 ). As the liquid cools in the test tube, 
 crystals of boracic acid separate and fall to the bottom : 
 they may be purified by re-crystallization from solu- 
 tion in hot water. It sometimes crystallizes in 
 feathery forms, at other times in the form of minute 
 discs, when they exhibit under the polariscope, crosses 
 and coloured rings, similar in appearance to those 
 exhibited by oxalurate of ammonia. A solution of 
 borax and also boracic acid might be tried with 
 advantage in some preparations. 
 
 15. Sulphate of cadmium, made by dissolving the 
 oxide of cadmium in sulphuric acid, when it is 
 evaporated on a slide, exhibits minute radiating or 
 circular crystals, which exhibit nearly the same 
 appearance under the polariscope, as the crystals of 
 boracic acid, oxalurate of ammonia. &c. 
 
 16. Carmine. This pigment is much used for stain- 
 ing tissues, and also for colouring the internal parts of 
 the infusoria which absorb it, and to make the motion 
 of the cilia of various aniinalculae more apparent. 
 
188 A MANUAL OF 
 
 17. Gold size added to Brunswick black renders it 
 less liable to crack. It is better to keep nearly all the 
 cements some time before use. 
 
 18. Chromic acid (Cro 2 Ho 3 ). If 5 measures of sul- 
 phuric acid (SOJHo.,) be added to 4 measures of 
 bichromate of potass (Cr 3 O 5 Ko 2 ), beautiful crimson 
 crystals of chromic anhydride are obtained. These 
 crystals must be dried at a gentle heat on a brick or 
 porous tile, after which a small quantity of water may 
 be added to them, when chromic acid is formed. It 
 is chiefly used for hardening and preserving nervous 
 tissues, &c. It is best kept in a well- stoppered bottle 
 and made when required for use. The test for 
 chromic acid is acetate of lead, which gives a yellow 
 precipitate. It is as well to keep a solution of chromic 
 acid in glycerine. 
 
 19. Oxygen (O) is best prepared by mixing equal 
 parts of oxide of manganese and chlorate of potass; 
 they may then be thoroughly powdered and mixed 
 carefully in a mortar, after which the mixture is placed 
 in a retort, and a moderate heat from the spirit lamp 
 applied ; or if a larger quantity is wanted, it is better 
 to make it in an iron retort placed in the fire. The 
 oxygen will then pass off freely. It is as well to let 
 the gas pass through a wash or Woulff's bottle contain- 
 ing water, as it often contains a slight percentage of 
 chlorine when made by this process, After the oxygen 
 has thus been well washed, it may be stored or col- 
 lected in the small gas holder (see Pig. 17), where it 
 will be ready for immediate use in connection with 
 the gas or animalcule cell. Many of these gases may 
 be temporarily stored in these gas-holders, and their 
 action, if any, on organic life noticed. 
 
MICROSCOPIC MOUNTING. 189 
 
 20. Hydrogen (H) is best made by adding diluted 
 sulphuric acid (SO 2 Ho 2 ) to zinc; the hydrogen then 
 passes off and may be washed and collected as with 
 oxygen (use caution when near fire, gas, &c). 
 
 21. Nitrogen (N) is best made by heating nitrite of 
 ammonia (N"'O (N V H 4 O)', when the nitrogen passes 
 off freely and may be collected like oxygen. 
 
 22. Carbonic acid gas (CO 2 ), or as it is more 
 properly called carbonic anhydride, is best prepared 
 by treating marble (calcic carbonate (COCao") with 
 hydrochloric acid (HC1), when carbonic anhydride is 
 given off and the useful substance, chloride of calcium, 
 remains behind in a fluid state ; if wanted for use, it 
 must be purified, &c. (see Recipe 12) : the gas may be 
 collected and stored in a gas holder like oxygen. 
 
 23. Chlorine (Cl) is best prepared by mixing to the 
 consistency of cream some hydrochloric acid (HC1), 
 and oxide of manganese (MnO 2 ). This must be put 
 into the glass retort Pig. 28), and care should be 
 taken that the entire surface of the glass is wetted with 
 the mixture, or the glass might break. A gentle heat 
 from the spirit-lamp should then be applied, when 
 the gas comes off freely. It cannot be stored in the 
 gas-holder like oxygen, as it is absorbed freely by 
 water; it must therefore be made when wanted. 
 Great care should be taken in making this gas, and it 
 is better to make it in very small quantities, as it 
 causes great irritation of the lungs when breathed. 
 
 24. Sulphuretted hydrogen (SH 2 ) P * is best prepared 
 by acting on sulphuret of iron (FeS) with diluted 
 sulphuric acid (SO 2 Ho 2 ), when the gas is given off 
 freely without any heat being applied : it cannot be 
 stored well in the gas-holder, as it is largely absorbed 
 
 * When Ps occurs it means " dangerous." 
 
190 A MANUAL OF 
 
 by water. Great care must also be used in making it, as 
 it is extremely deleterious and dangerous or fatal when 
 breathed. Small quantities only should be made at 
 one time. All of the gases that can be stored for 
 temporary use in the glass gas-holder should be done 
 so, and when wanted, the weights applied to the top 
 according to the pressure required; one end of the 
 India-rubber tubing must then be fixed on the gas- 
 holder (Fig. 17) and the other on the gas-cell (Pigs. 9 
 and 10). (See description, Chapter I). 
 
 25. Millon's Test. This test is prepared by dissolv- 
 ing mercury in an equal weight of nitric acid. "When 
 the acid is poured upon the metal, nitric oxide (N 2 O 3 ) 
 is freely evolved: after this ceases, a gentle heat must 
 be applied until the whole of the metal is dissolved; 
 and after some time when crystals have been formed, 
 the remaining liquid may be poured off and kept in a 
 stoppered bottle. When a substance requires to be 
 tested, it must be placed in this fluid and the test tube 
 held over a gas jet or spirit-lamp until it boils, when 
 the substance will be coloured red if it answers to the 
 nature of the test. Albumen, caseine, chondrine, 
 crysalline, epidermis, feathers, fibrine, gelatine, gluten, 
 horn, legumine, proteiiie, silk, wool, are all coloured 
 by this test, and the following when pure are not : 
 Cellulose, chitine, cotton, gum (Arabic), linen, and 
 starch." 
 
 26. Bichromate of potass (Cr 2 o 5 Ko 3 ). This salt is 
 chiefly used for the preparation of chrornate of lead 
 (CrO 3 Pbo"), which is largely used in opaque injections. 
 It is made as follows : To a saturated solution of 
 bichromate of potass (Cr 3 O 5 Ko 3 ) acetate or nitrate of 
 lead (N 3 4 Pbo") is added, when a yellow precipitate, 
 
MICROSCOPIC MOUNTING. 191 
 
 which is the eliminate of lead, is almost immediately 
 ohtained ; well wash and store for use. The crystals 
 of hichromate of potass form a heautif ul object, more 
 especially under the polariscope. 
 
 27. Schnitzels Test. The action of this test is as 
 follows : Wash the substance which is to be examined 
 in water, pour off the water, and then moisten it with 
 a drop of syrup; add sulphuric acid (SO 2 Ho 2 ) one 
 drop. The reaction produces a purplish red colour, 
 if the substance contains either muscular tissue, cor- * 
 puscles of blood, pus and mucus, epidemic and epithe- 
 lial scales, hairs, feathers, horn, whalebone, cellular 
 parts of algso, &c. ; the reaction is not produced in 
 areolar tissue, elastic tissue, gelatine, and chondrine, 
 chitiiie, silk, cellulose, gum, starch, or vegetable mucus. 
 
 28. Schulze's Test. This, according to the Micro- 
 graphic Dictionary, is prepared as follows. It is used 
 as a test for cellulose, which it colours blue : 
 
 "Dissolve zinc in hydrochloric acid (HOI), evaporate 
 the solution with excess of zinc until it acquires the 
 consistence of syrup, and dissolve in this enough 
 iodide of potassium to saturate it; iodine is then 
 added, and the solution diluted with water if necessary. 
 This re-agent has the consistence of strong sulphuric 
 acid, and of a pale yellowish brown. It must, of 
 course, be kept in a stoppered bottle. It is also well 
 to keep this and the before-mentioned tests in a small 
 drop bottle (see Pig. 12, drop bottles)." 
 
 29. Staining fluid for tissues. 
 
 Soluble aniline blue, -J grain. 
 Distilled water, 1 ounce. 
 Alcohol, 25 drops, 
 This fluid is not acted upon by acids or alkalies. 
 
192 A MANUAL OF 
 
 30. Solutions of nitrate of silver (N0 3 Ago) may be 
 used of various strengths ; it will also be found useful 
 when dissolved in glycerine. In experiments with 
 staining tissues it is better to begin with a solution of 
 a moderate strength 
 
 Nitrate silver, 1 scruple. 
 Water, 2 drachms. 
 
 31. Solution of Osmic acid (OsO 2 ). 
 
 Osmic acid, 1 part, 
 Distilled water, 100 parts. 
 
 is the strength generally used for staining ; although, 
 of course, circumstances will alter this. It is chiefly 
 used for distinguishing nerve fibres from the surround- 
 ing substances ; this fibre it generally colours almost 
 black. Pat cells and oil globules are also coloured. 
 
 32. A solution of tannin is much used, for although 
 it does not stain animal membrane, yet it alters its 
 character to such a degree that points of structure 
 may be often known by this change. 
 
 33. Injecting fluid (Prussian blue). 
 
 Glycerine, 1 ounce. 
 
 Spirits of wine, 1 ounce. 
 
 Eerrocyanide of potassium, 12 grains. 
 
 Tincture perchloride of iron (Ee 2 Cl 6 ), 1 drachm. 
 
 Hydrochloric acid (HC1), 5 drops. 
 
 Water, 4 ounces. 
 
 " The ferrocyanide of potassium is to be dissolved 
 in one ounce of the water, and the tincture of per- 
 chloride of iron added another ounce of water. These 
 solutions should be mixed very gradually, and well 
 
MICROSCOPIC MOUNTING. 193 
 
 shaken in a bottle. The iron being added to the 
 solution of the ferrocyanide of potassium. "When 
 mixed, these solutions should produce a dark blue 
 mixture, in which no precipitate is observable. 
 Naphtha is to be mixed with the spirit, and the 
 glycerine and the remaining ounces of water added ; 
 lastly, this colourless fluid is to be mixed with the 
 dark fluid, it being well shaken up in a large bottle 
 during the admixture. The tincture of perchloride 
 of iron is generally sold at the druggists, under the 
 name of the muriated tincture of iron." 
 
 34. Staining fluid (TurnbulVs blue). 
 
 Ferricyanide of potassium, 10 grains, 
 Sulphate of iron, 5 grains. 
 Water, 1 ounce. 
 Glycerine (Price's), 2 ounces. 
 Alcohol, 1 drachm. 
 
 The iron is to be dissolved in a little of the water and 
 mixed with the glycerine, this is then to be gradually 
 mixed with the solution of the ferricyanide, as in the 
 last recipe. 
 
 35. Doctor Elizabeth Hog gam Staining Fluid, 
 Solution. 
 
 One per cent, solution of perchloride of iron in 
 distilled water, thus Take 1 gramme of pure iron, 
 dissolve by the action of hydrochloric acid, and add 
 distilled water to 100 grammes. Keep in stoppered 
 bottle. 
 
 A solution of pyrogallic acid in distilled water, of 
 the same strength as the above, should also be made, 
 and kept in stoppered bottle. 
 
 Q 
 
194 A MANUAL OF 
 
 36. Logwood Staining 
 
 Extract hsemalox, 6 grammes. 
 
 Albumen, 18 grammes. 
 
 Mixed thoroughly in a mortar. Add gradually whilst 
 stirring 
 
 Distilled water, 28 cub. cent. 
 Filter. To the filtrate add 
 
 Alcohol (proof), 1 drachm. 
 
 Keep the solution in a stoppered bottle for a few days 
 before using. Eor staining, 5 to 10 drops are to be 
 added to half a watch-glass of distilled water; this 
 solution should be filtered before use. Sections which 
 have been removed from common alcohol, are to be 
 placed in the dilute solution for from ten to twenty 
 minutes, and then to be washed in distilled water. 
 
 37. Dammar varnish 
 
 Gum Dammar in powder, % ounce. 
 
 Dissolve in turpentine, 1^ ounces. 
 Enter. 
 
 Gum mastic, ^ ounce. 
 
 Dissolve in chloroform, 2 ounces. 
 Eilter. Mix the two filtered solutions, and again 
 filter. 
 
 38. Muller's hardening fluid 
 
 Potassium bichromate, 2 parts. 
 
 Sodium sulphate, 1 part. 
 
 "Water, 100 parts. 
 
 Dissolve. Keep the tissue in this solution for one or 
 two weeks, and then place in common alcohol for two 
 or three days, after which it is ready for making 
 sections. 
 
 A two per cent, solution of bichromate of potash is 
 also much used in hardening tissues. 
 
MICROSCOPIC MOUNTING. 195 
 
 39. A greenish fluid for injecting may be made by 
 using one grain, or less, of the sulphate of iron to 
 ten grains of the ferricyanide of potassium, the other 
 ingredients to be the same as in the last recipe. 
 
 40. Injecting fluid (Carmine) Dr. Heale. 
 Carmine, 5 grains. 
 
 Glycerine, with about eight or ten drops of hydro- 
 chloric acid (HC1), \ ounce. 
 Glycerine, 1 ounce. 
 Alcohol, 1 drachm. 
 "Water, 6 drachms. 
 Ammonia (NH 4 Ho), a few drops. 
 
 Mix the carmine with a few drops of water, and when 
 well incorporated, add about five drops of liquor 
 ammonia (NH 4 Ho). To this dark red solution about 
 half an ounce of the glycerine is to be added, and the 
 whole well shaken in a bottle ; then, very gradually, 
 pour in the acid glycerine, frequently shaking the 
 bottle during admixture. Test with blue litmus paper, 
 and if not of a very decidedly acid reaction, a few 
 drops more acid may be added to the remainder of 
 the glycerine. Lastly, gradually and thoroughly 
 mix the alcohol and water, then add to the glycerine 
 portion, and again thoroughly mix. This fluid, like 
 the Prussian blue, may be kept all ready prepared, and 
 injections may at any time be made with it rapidly. 
 41. Dr. Carter's carmine injecting fluid. 
 
 Pure carmine, 60 grains. 
 
 Liq. ammon. fort. (P.L.), 120. 
 
 Glacial acetic acid, 86 minims, 
 
 Solution of gelatine (1 to 6 water), 2 ounces. 
 
 Water, 1^ ounces. 
 
 o 2 
 
196 A MANUAL OP 
 
 The carmine is to be dissolved in the solution of 
 ammonia and filtered if necessary. With this mix 
 thoroughly an ounce and a half of the hot solution of 
 gelatine. The remaining half ounce of gelatine is to 
 be mixed with the acetic acid, and dropped, little by 
 little, into the solution of carmine, stirring smartly 
 during the whole time. Eor an injecting fluid which 
 will run freely through the most minute capillaries, 
 and one that will not tint the tissues beyond the 
 vessels themselves, there perhaps cannot be a much 
 better recipe for the purpose. It is also well adapted 
 for specimens which are to be mounted in Canada 
 balsam, but not for those to be preserved in glycerine 
 (see Injection, Chapter V). 
 
 42. Red injection (opaque). 
 
 Vermilion, 164 grains (apoth. wt.) 
 Gelatine (swollen), 4 ounces (avoid, wt.) 
 
 Dissolve the gelatine in one ounce of water ; then add 
 
 the vermilion, stir well, and strain. 
 
 43 . Yellow injection (opaque) . This is prepared with 
 chrome yellow, formed by adding acetate of lead to 
 bichromate of potass. 
 
 Acetate of lead (C 2 (Me 2 )O 3 Pbo"), 380 grains. 
 
 Bichromate of potass (Cr 2 O 5 Ko 3 ) 152 grains. 
 
 Gelatine (swollen), 8 ounces. 
 
 Dissolve the gelatine in one ounce of water, and if 
 too thick, add more water; then dissolve the acetate 
 of lead in this warm fluid, and finally add the bichro- 
 mate of potass. This is the only yellow (opaque) 
 injection that is wanted. 
 
 44. Slue injection.- 
 
 Prussian blue, 73 grains. 
 Oxalic acid, 73 grains. 
 Gelatine (swollen), 4 ounces, 
 
MICROSCOPIC MOUNTING. 197 
 
 Dissolve the gelatine in one ounce of water, reduce 
 the oxalic acid to powder in a mortar ; then add the 
 Prussian hlue and dissolve in the warm gelatine fluid. 
 
 45. White Injection (opaque). 
 
 Acetate of lead (C 2 (Me 3 )O 2 Pbo"), 190 grains. 
 
 Carhonate of potass (COKo 2 ), 83 grains. 
 
 Gelatine (swollen), 4 ounces. 
 
 Dissolve the gelatine in 1 ounce of water; then add 
 to the warm fluid the acetate of lead, which dissolve 
 and filter. Dissolve the carbonate of potass in 
 J ounce of water, mix the acetate of lead solution, 
 and strain. It is best to prepare all these opaque 
 injections when wanted (see Injection, Chapter V). 
 
 46. Blue injecting fluid (transparent). 
 
 Glycerine, Price's, 2 ounces. 
 
 Tincture of perchloride of iron (Pe 2 Cl 6 ), 10 drops. 
 Eerrocyanide of potassium (K 4 Fe"Cy 6 ), 3 grains. 
 Strong hydrochloric acid (HC1), 3 drops. 
 Water, 1 ounce. 
 
 Mix the tincture of iron with one ounce of the 
 glycerine ; and the ferrocyanide of potassium dis- 
 solved in a little water with the other ounce. 
 These solutions are to be mixed very gradually in a 
 bottle, and to be well shaken during the admixture. 
 The iron solution must be added to the ferrocyanide 
 of potassium, and lastly, the water and hydrochloric 
 acid are to be added. Alcohol, one or two drachms, is 
 often added to the above mixture. This fluid does not 
 deposit any sediment, and it may be kept for a long 
 time if wanted. Injections coloured with it may be 
 stained with the following carmine fluid : 
 
198 A MANUAL OF 
 
 47. Carmine staining fluid. 
 
 Carmine, 10 grains. 
 
 Strong liquor ammonia (NH 4 Ho), ^ drachm. 
 
 Glycerine, Price's, 2 ounces. 
 
 Distilled water, 2 ounces. 
 
 Alcohol, ^ ounce. 
 
 By agitation and the aid of heat, the carmine is to 
 be dissolved in the ammonia. This ammoniacal solu- 
 tion to be boiled for a few seconds in a test-tube, and 
 allowed to cool. When an hour or so has elapsed, 
 the excess of ammonia will have escaped; the 
 glycerine and water may then be added, and the 
 perfectly clear supernatant fluid poured off and kept 
 for use. If after a time it is found that carmine is 
 deposited at the bottom of the bottle, owing to the 
 escape of ammonia, a few drops of liquor ammonia 
 may be added to the solution. 
 
 48. Fluid for preserving embryonic tissues (H. Muller). 
 
 Eichromate of potass (C 2 O 5 Ko 2 ), 30 to 40 grains. 
 Sulphate of soda (SO 2 Nao 2 ), 15 grains. 
 Distilled water, about 3 ounces. 
 
 49. Canada balsam and slackened lime (CaHo 2 ) will 
 be found a good cement for many purposes. 
 
 50. Ground borax, mixed with plaster of Paris, makes 
 a good cement. Might be used for large cells, &c. 
 
 51. Polishing powder for lenses and metal work. 
 Mix equal parts of solutions of oxalic acid (C 2 O 2 Ho 2 ) 
 and sulphate of iron. Dry the precipitate, calcine, 
 and use as a fine powder. 
 
 52. French cement. A certain quantity of india- 
 rubber scraps are carefully melted over a clear fire in 
 a covered iron pot, but they must not be permitted to 
 
MICROSCOPIC MOUNTING. 199 
 
 catch fire. When the mass is quite fluid, lime in a 
 perfectly fine powder, having been slacked by 
 exposure to the air, is to be added in small quantities 
 at a time, the mixture being well stirred. "When 
 moderately thick it is removed from the fire and well 
 beaten in a mortar and moulded in the hands until of 
 the consistence of putty. It may then be coloured by 
 vermilion or other colours. This cement is quite safe 
 for mounting large and thick objects in fluid, as it 
 rarely gets hard. 
 
 53. Essential oil of lemon is much used in the exa- 
 mination of pollens and other structures, as it tends 
 to render them more transparent. 
 
 54 Iodine. Chiefly used for dyeing and rendering 
 objects more distinct; also as a re-agent for starch, 
 &c. An aqueous solution is best for ordinary use, 
 but a much stronger solution may be made by dis- 
 solving it in alcohol ; the strongest is made by dis- 
 solving it in a solution of iodide of potassium (KI). 
 Solutions of iodine in chloride of zinc (ZnCl 2 ), and 
 iodide of zinc (ZnI 2 ), are useful re-agents for cellulose 
 (see Schulze's Test, 28). 
 
 55. Mica, often called talc, is now used principally 
 for burning objects to a red heat, being much cheaper 
 than platinum. The object is placed on a small piece 
 of mica and held over the spirit-lamp until the 
 required state of examination or preparation is 
 attained. 
 
 56. Carbolic acid, 1 drachm. 
 Alcohol, 2 drachms. 
 Distilled water, 12 ounces. 
 
 Dissolve the carbolic acid with the alcohol, and add to 
 
200 A MANtJAL OF 
 
 the water; then boil for ten minutes and bottle for 
 use. This forms a good preservative fluid for many 
 animal and vegetable tissues. 
 57. Arsenious acid (AsHo 3 ) saturated solution, 1 part* 
 
 Camphor water, distilled, 2 parts. 
 Mix and bottle for use. A tolerably good preservative 
 for animal tissues ; but very poisonous, and not much 
 used. 
 
 58. Acetate of aluminium (C 2 (Me 2 )0 2 'Al 2 '"), 1 part. 
 
 Distilled water, 4 parts. 
 
 Very good for preserving vegetable colours, as in the 
 case of desrnids and other algae. 
 
 59. Chloride of zinc (ZnCl 2 ) 20 grains. 
 
 Distilled water, 1 ounce. 
 
 Perhaps the best preservative for most animal tissues, 
 though it exerts a slight coagulating action on the 
 tissues. A lump of camphor should be kept in it. 
 60. Litharge, 1 ounce. 
 
 Plaster of Paris, 1 ounce. 
 Resin (powdered), 1 ounce. 
 Treacle, 1 ounce. 
 
 Mix with gold size until a soft putty consistency is 
 acquired ; then use. This cement will be found 
 useful for mending and making, parts of different 
 apparatus, aquaria, &c. 
 
 61. Plaster of paris mixed with a weak solution 
 of chloride of calcium, will also be found useful for 
 the same purpose. 
 
 62. Castor oil is much used for some crystals where 
 the balsam or dammar does not suit. Care should 
 be taken that it is pure. 
 
 63. A strong syrup, made by boiling loaf sugar in 
 
MICROSCOPIC MOUNTING. 201 
 
 distilled water until it crystallizes, when a drop is 
 dropped upon a slip of glass. It may then be stored 
 in a stoppered bottle with a small lump of camphor 
 floating in it. This solution will be found very useful 
 for preserving many animal and vegetable structures ; 
 if it crystallizes too much, a few drops of chloride of 
 calcium solution should be added to it. 
 64 Glycerine jelly. 
 
 Gelatine, 1 ounce. 
 
 Glycerine, 6 drachms. 
 
 Camphorated spirits of wine, ounce. 
 
 Soak the gelatine in cold water until it swells up and 
 becomes soft; then place it in a small jar, which 
 stand in a basin or larger jar of boiling water, and 
 dissolve by the action of the same heat continued ; 
 when dissolved and quite cool, but not set into a 
 jelly, add a small quantity of the white of an egg ; 
 then boil the mixture until the white of the egg sets ; 
 filter through fine flannel, and add the glycerine to 
 which has been previously added J ounce of strong 
 camphorated spirits of wine. Mix thoroughly, and 
 store in bottle for use. When wanted, it must be 
 placed in a jar of boiling water, which renders the 
 jelly fluid and ready for use. 
 
 65. Films to exhibit absorption spectra. 
 
 Gelatine, 1 ounce. 
 
 Soak in water until quite soft and swollen ; then 
 dissolve with heat, and, if necessary, add a small 
 quantity of water; pour the fluid into flat evapo- 
 rating dishes, or common plates will do. The 
 dishes or plates must be previously greased to prevent 
 the gelatine sticking. Let the water evaporate from 
 
202 A MANUAL OF 
 
 the gelatine until it becomes nearly hard; then 
 separate it in sheets from the plates and cut up into 
 small squares about f or f of an inch square. These 
 squares may then be kept in a box for use. When 
 wanted they may be soaked in the fluid that is to 
 be tested with the spectroscope, and placed between 
 glass slips. This plan will be found much easier and 
 cleaner than putting the various solutions in glass 
 cells. In many cases these prepared plates may be 
 kept. The gelatine is also sold in sheets by most 
 artists' colourmen. 
 
 66. White gutta percha. Dissolve gutta percha in 
 chloroform; then put it into a small two-necked 
 WoulfFs bottle (see Pig. 18.) Pass chlorine gas 
 through it until it is nearly, if not quite, white. 
 Pour into a dish, let the chloroform evaporate if slabs 
 are wanted ; or mix any powdered colour or tint with 
 it, and then evaporate. It will be found very useful 
 for opaque mounting (see Chapter II.) 
 
 67. A good plan to render wood plastic is to place 
 it in hydrochloric acid (HC1), and subject it to a 
 severe atmospheric pressure under the air pump, 
 when the hydrochloric acid enters into all the pores 
 and makes the wood softer ; it is then much easier 
 to cut with the section cutter. But as hydrochloric 
 acid will slightly attack the edge of the knife, 
 it is necessary both to well wash the wood and also 
 use plenty of water while cutting it. If care is taken 
 the position of the fibres will not be altered much, if at 
 all. Well wash the sections in water before mounting. 
 
 68. Gold size and gilders' whiting mixed until of 
 the consistency of thick treacle, makes a good cement 
 for sealing cells, &c. 
 
MICROSCOPIC MOTOTING. 203 
 
 69. Canada balsam cement should be made by eva- 
 porating nearly all the turpentine from the balsam 
 by the aid of heat. To test when it has arrived at its 
 right stage, drop a small drop on a glass slip, when, if 
 right, it should be quite hard, but not brittle. This 
 cement is chiefly used for fixing bone, teeth, shells, 
 &c., to glass whilst they are being cut and ground. 
 
 70. Berlin black, which can be obtained at most 
 oil and colourmen's, makes a much better varnish for 
 finishing cells, &c., than Brunswick black and others. 
 It dries with a slightly dull surface. 
 
 71. Gum water thickened with gilders' whiting 
 until of the consistency of treacle, and to which 
 two drops of glycerine to every J ounce has been 
 added, will in certain cases be found a very useful 
 cement. 
 
 72. Cement for glass, fyc. Another useful cement 
 is made by mixing, when wanted, plaster of Paris and 
 the white of an egg, The egg must be well beaten 
 and the plaster mixed with it until of about the con- 
 sistency of treacle. Use it directly, as it soon sets ; 
 it must be made fresh when wanted. This cement 
 is useful for fixing glass cells to glass slips, when any 
 other cement could not be used on account of the 
 solvent powder of the fluid in which the object might 
 be mounted, say, balsam or weak spirit. It will also 
 be found useful for other purposes. 
 
 73. Silicious cement. 
 
 Colloid silica, J ounce. 
 Thick gum water. ^ ounce. 
 
 Gilders' whiting sufficient to make it of the con- 
 sistency of treacle. This cement will be found useful 
 
204 A MANUAL OF 
 
 in protecting corks, &c., from the fumes of acid, &c. 
 74 Glycerine, 1 ounce. 
 
 Acetic acid, -J ounce- 
 
 Mix and bottle for use. "Will be found a useful pre- 
 servative fluid for many minute insect and other 
 objects. 
 
 75. Deane's compound. 
 
 Gelatine, 1 ounce. 
 
 Honey, 5 ounces. 
 
 Water, 5 ounces. 
 
 Spirit wine, ^ ounce. 
 
 Creosote, 6 drops. 
 
 The gelatine is soaked in the water until soft, and 
 then added to the honey, which has been previously 
 raised to a boiling heat in another vessel; boil the 
 mixture. After it has slightly cooled, add the creosote, 
 which has been previously mixed with the spirit, then 
 filter through flannel, When either this compound or 
 the glycerine jelly (Eecipe 60) require to be used, 
 they must be warmed, and a drop placed in the 
 centre of a warmed slide ; put the object in this and 
 cover with a slightly moistened thin glass cover, clean 
 the slide from the superfluous jelly, and finish by 
 applying a coating of Berlin black. Both the Deane's 
 compound and the glycerine jelly are best kept in one 
 of the collapsible tubes (see Plate 4, Tig. 58.) 
 
 76. Halfs liquid. 
 
 Bay salt, 1 grain. 
 
 Alum, 1 grain. 
 
 Distilled water, 1 ounce. 
 
 Dissolve and mix. This forms a good preservative 
 fluid for many of the algae and other objects. 
 
MICROSCOPIC MOUNTING. 205 
 
 77. Cement for fixing metals to glass or earthenware. 
 Mix alum and plaster of Paris (finest kind) with 
 water to a liquid state, or to a convenient paste. It 
 forms an excellent cement for many purposes, and 
 resists the action of water for a considerable time. 
 
 78. White cement. Dissolve gum mastic in chloro- 
 form, and add nitrate of bismuth until it is of a dead 
 white colour. When the cement gets too thick by the 
 evaporation of the chloroform, add more until it is of 
 the right consistency. It answers well for sealing 
 cells, especially where the objects are mounted in 
 glycerine. It will also be found very useful for many 
 purposes. Oxide of Zinc and Canada balsam is often 
 used for the same purpose. 
 
 79. Glycerine preservative fluid. 
 
 Distilled water, 3 ounces. 
 
 Glycerine, 1 ounce. 
 
 Camphorated spirit, J ounce. 
 
 (Made by dissolving camphor in spirits of wine.) Mix 
 and store in 6-ounce phial bottle for use. This fluid 
 will be found very useful in mounting algae, especially 
 desmids. It will also be found useful for other 
 objects. 
 
 80. Sweet spirits nitre, ^ ounce, 
 
 Glycerine, ^ ounce, 
 
 is much used in preserving some of the delicate dis- 
 sections of insects. 
 
 81. If cupric hydrate (hydrated oxide of copper) is 
 dissolved in ammonic hydrate (liquor ammonia), it 
 forms a blue solution ; but if metallic copper is put 
 into this it forms a nearly colourless compound, and 
 when diluted with water will be found a useful pre- 
 servative fluid for some substances. 
 
206 A MANUAL OF 
 
 82. A saturated solution of salicylic acid in water 
 will be found very useful for the preservation of algae 
 and other delicate vegetable objects. 
 
 83. Shellac dissolved in a saturated solution of 
 borax and coloured with powder colours as required, 
 will be found a very useful varnish for finishing slides. 
 
 "Most microscopic measurements are under the 
 hundredth of an inch ; one hundred-thousandth of 
 an inch can only be measured with certainty when 
 magnified by the ^th or ^ . The requirements of 
 the case, therefore, may be stated in decimals of an 
 English inch by * 00101, and if the two ciphers next 
 the decimal point be struck out, and the first number 
 be considered the unit, it may be written 1*01, in 
 which a thousandth of an inch is the unit. This 
 method will embrace nearly every microscopic magni- 
 tude in three consecutive figures. 
 
 The foreign measures are the millimetre and the 
 French and Prussian lines. The two latter are so 
 nearly equal, that the same rule will serve for the 
 conversion of both. 
 
 A millimetre contains -05937 English inch, or 
 39*37; according to the method proposed, the length 
 to be converted will seldom amount to one-fourth of 
 this. To convert millimetres into thousandths, shift 
 the decimal point one place to the right and multiply 
 by 4; if greater accuracy be required, subtract 1^ 
 from, the second place of decimals for each of the 
 nearest numbers of units of the product. Thus 
 O mm -250 becomes 2'50, which X 4=10*00, from which 
 subtract t *15 ; and 9**35 is obtained as the value in 
 thousandths of an English inch, while O mm '25 is equal 
 to 9^84, which differs from the former by a quantity 
 too small to measure. 
 
MICROSCOPIC MOUNTING. 207 
 
 To convert thousandths of English inches into 
 millimetres, add 1^- in the second place of decimals 
 for the nearest number of units in the sum, divide by 
 4, and shift the decimal point one place to the left; 
 thus to 9*-84 add H5 and the sum 6-999-7-4=2-498, 
 and shifting the decimal point mm *2498, which does 
 not differ sensibly from mm< 25, the correct quantity. 
 
 A French line contains *0888 English inches. To 
 convert lines into thousandths of an inch, shift the 
 decimal point one place to the right, and multiply by 
 9 ; if greater accuracy be required, subtract 1^ from 
 the second place of decimals for each of the nearest 
 number of units in the product. Thus 0'"'125 becomes 
 1-25 which x9=ir-25, from which subtract H4, and 
 the value in thousandths is found to be 11** 10, which 
 is correct. 
 
 To count thousandths into lines, add 1^ in the 
 second place of decimals for each of the nearest 
 number of units in the sum, divide by 9, and shift the 
 decimal point one place to the left, thus : to 11^10, 
 add ^14, the sum 11*25 divided by 9, and the decimal 
 point shifted one place to the left gives 0"'-125 as 
 before. In most cases it will be unnecessary to apply 
 the corrections noticed above; but by remembering 
 the short rules given, anyone on reading a foreign 
 work may correct the measurements as he reads, and 
 insert them in the margin without delay or interfering 
 with his progress. 
 
209 
 
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 3 1 
 
 
 
 
 
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 S 
 
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 05 eo 
 
 * 00 S< 
 
 i si 
 
 tjt 00 t 
 
 r-l t~05 
 
 us 01- 
 
 S^l 00 05 
 
 SS 2S 
 
 CO ^-00 
 
 CO O 00 
 
 I II 
 
 i 1 
 
 c ^ -c o 
 
 
 
 
 c : s c .s ^ 
 
 (H PH PH C 
 
 t~ 00 OS O rH 
 
 
 -. 
 
 s 
 
 3 S 1 8I 
 
 s s 2 S " ? 
 
 ill* ++ 
 
 S H I 
 
 I ^ ogsll 
 
 s 1 - I PI III 
 
 . P5 -q t^co 
 
 g I II II II II II 
 
 s a i 
 
 
INDEX. 
 
 P. Paragraph. R. Recipe. S. Slide. 
 
 AOAREA, or mites, P. 95 
 
 Acetate of aluminium fluid, R. 58 
 
 Acetic acid, use of, P. 237 
 
 Adulterations, P. 251, &c. 
 
 Air bubbles, P. 72 
 ,, pump, P. 27 
 
 Alcohol, use of, P. 248 
 
 Algse, to mount, P. 98 
 
 Ammonic oxide of copper, use of, P. 244 
 
 Anguillula glutinis, to mount, P. 99 
 
 Animals, to kill for injection, P. 139 
 
 Anoplura, to mount, P. 100 
 
 Antennae of insects, to mount, P. 101 
 
 Antheridia, to mount, P. 103. 
 
 Anthers of flowers, to prepare, P. 102 
 
 Antlia, to mount, P. 104 
 
 Aphidae, to prepare and mount, P. 105 
 
 Apotheciuni, to mount, P. 107 
 
 Apparatus for cleaning diatoms, P. 21 
 ,, for drawing, P. 29, 30, 31 
 ,, for drying slides, P. 6 
 ,, for making gasses, &c., P. 25 
 ,, used in collecting, P. 158 
 ,, used in mounting, P. 2, &c. I 
 ,, used in observing minute | 
 
 forms of life, P. 263 
 ,, for measuring thin glass, 
 
 P. 39 
 
 ,, for reflected light, P. 41 
 ,, for dark stage objects, P. 41 
 
 Arachnida, to prepare and mount, 
 P. 106 
 
 Archegonium, to mount, P. 108 
 
 Arsenious acid fluid, R. 57 
 
 Australian meat tins, P. 51. 
 
 BEETLES (Coleoptera), to mount, P. 117 
 
 ,, where to find, P. 185 
 Bell glasses, P. 46 
 Berlin black varnish, R. 70 
 Bichloride of mercury, saturated solu- 
 tion of, R. 10. 
 Bichromate of potass, to prepare, &c., 
 
 R. 26 
 
 Black varnish, R. 11 
 Bleaching apparatus, P. 8 
 Blights (Micro-fungi), to mount, P. 109 
 Blood, to examine, prepare, and mount, 
 
 P. 110 
 
 Blow-pipe, P. 56 
 Bone, examination, making sections of, 
 
 &c., P. Ill 
 Books for preservation of specimens, 
 
 P. 164 
 Boracic acid,'R. 14 
 
 ,, used in mounting, P. 91 
 Borax and plaster of Paris cement, R. 50 
 Boxes used for collecting, P. 161 
 Bramble leaf brand, S. 34 
 Brands (Micro-fungi), to mount, P. 112 
 British diamond beetle, how to mount, 
 
 S. 22 
 BritishMiamond beetle, where "to find, 
 
 P. 186 
 
 Brunswick black, R. 17 
 Butterflies, where to find, P. 186 
 how to catch, P. 181 
 
 CALCIUM (lime), tests for, P. 218 
 Camera Lucida, P. 30, 31 
 Canada Balsam, R. 13 
 
212 
 
 INDEX. 
 
 Canada Balsam and lime cement, R. 49 
 
 cement, R. 69 
 Capsules and peristomes of moss (Hyp- 
 
 num rutabulum, S. 21 
 Carbazotic acid, use of, P 239 
 Carbolic acid fluid, R 56 
 Carbonates, to test for, P. 228 
 Carbonic acid gas, to prepare, R. 22 
 Carmine, R. 16 
 
 fluid (Dr. Carter's), R. 41 
 Castor oil, R. 62 
 Cayenne pepper, adulterations of, P. 
 
 252 
 Cell for the examination of insects, 
 
 &c., P. 7 
 Cement for fixing metals to glass or 
 
 earthenware, R. 77 
 for glass cells, &c., R. 72 
 ,, for glass covers, &c., R. 70 
 Chalk, foraminifera from, to prepare 
 
 and mount, &c. P. 113 
 to analyse, P. 214 
 Characese, see circulation in, P. 114 
 Chemicals used in mounting. P. 2 
 Chicorv, adulterations of, P. 256 
 Chloride of calcium, to make, &c., R. 12 
 ,, of zinc, a preservative fluid, 1 
 
 R. 59 
 
 Chlorides, to test for, P. 230 
 Chlorine gas. to make, R. 23 
 Chromic acid, to make, &c., R. 18 
 
 ,, use of, P. 238 
 Circulation, to observe, P. 116 
 Classification of slides, P. 211 
 Cleaning thin glass, S. 1 
 Coating collapsible tubes with wax, 
 
 P. 92 
 
 Cocoa, adulterations of, P. 259 
 Coffee, adulterations of, P. 255 
 Collecting bottle, P. 44 
 Colloid silica, or silicic acid, R. 9 
 Collomia seed, to observe and mount, 
 
 P. 118 
 
 Coloured cement, R. 2. 
 Common salt, for the preservation of 
 
 palates, &c., P. 87 
 Compressorium, P. 34 
 Confervoidese, to mount, P. 119 
 Constant cement, R. 1 
 Corallina, to observe and mount, P. 120 
 
 Corolla of pimpernal, S. 11 
 Corns, to mount, p. 121 
 Copper preservative fluid, R. 81 
 
 tests for, P. 221 
 
 Cork, used for dissections, &c., P. 122 
 Crystals, formed by the action of gases, 
 
 P. 7 
 
 ,, formed by electricity, P. 231 
 ,, of chlorate of potass, S. 27 
 ,, of oxalate of ammonia, S. 48 
 ,, of silver, S. 24 
 ,, to prepare and mount, forma- 
 tion of, &c., P. 123 
 Crucibles, P. 49 
 Culex, to mount, P. 124 
 Cuticle of a fern, (Poly podium vutgare), 
 
 S. 46 
 
 of ivy, S. 10 
 , , of plants, to prepare and mount , 
 
 P. 125 
 Cutting rock sections, P. 35 
 
 DAMMAR varnish, R. 37 
 Deane's compound, R. 75 
 Desmidiaeese, to clean, &c., P. 126 
 Desmids, how to collect, P. 167 
 whereto find, P. 196 
 Dialysing apparatus, P. 40 
 drum, P. 40, 52 
 Diatomacere, to clean, prepare, and 
 
 mount, P. 127 
 Diatoms, how to collect, P. 169 
 
 ,, separated according to their 
 
 specific gravity, P. 21 
 Different colours used in injections, 
 
 P. 139 
 
 Differential warm stage, P. 42 
 Dissecting microscope, P. 28 
 
 ,, needles, knives, &c., P. 11 
 
 slab, P. 20 
 Dissections, P. 128 
 Drawing, P. 262 
 
 ,, by artificial light, P. 261 
 
 ,, with the aid of the camera 
 
 lucida, P. 31 
 
 Drying apparatus for objects, P. 24 
 ,, apparatus for slides, P. 6 
 ,, objects by the aid of sulphuric 
 
 acid, P. 24 
 ,, objects under pressure, P. 64 
 
INDEX. 
 
 218 
 
 Dry objects, P. 62 
 
 ,, opaque mounting, P. 61 
 Dust, examination of, P. 59, 130 
 
 ECHINUS spines, to cut sections of , P. 131 
 Eels in paste, P. 99 
 
 Eggs of common garden white butter- 
 fly, S. 18 
 ,, of insects, to preserve and mount, 
 
 P. 132 
 
 Electrical cement, E. 6 
 Entozoa, preservation of, P. 133 
 Ether, use of, P. 247 
 Examination of objects, P. 62 
 
 , , of organic structures, P. 250 
 
 ,, of starches, &c., under 
 
 heat, P. 42 
 Extraction of crystalloids from colloids, 
 
 P. 40 
 
 Eye of house fly, S. 2 
 Eyes of insects, how to dissect, P. 128 
 
 FBATHERS of birds, how to mount, P. 133 
 Fibres of cotton, S. 32 
 
 ,, of wool, S. 31 
 Films for spectrum analysis, R. 65 
 Finder for foraminifera, P. 22 
 Flour, to analyse, P. 214 
 Fluid for preserving embryonic tiasues, 
 
 R. 48 
 
 ,, which prevents rupture by os- 
 mosis, S. 45 
 Foraminifera from sea sand, S. 13 
 
 from chalk, S. 36 
 ,, how to collect, &c., P. 183 
 
 ,, to clean, examine, and 
 
 mount, P. 135 
 Forming crystals, P. 123 
 Fossil bones, to prepare, P. Ill 
 Freeing slides from air bubbles, P. 27 
 French cement, R. 52 
 Fresh-water shrimps, where to find, 
 P. 187 
 
 GALL insects, to keep, P. 173 
 Galvanic battery, use of, P. 232 
 Gas holder, P. 14 
 
 ,, stand, P. 13 
 
 Gizzard of cricket, how to dissect, P. 128 
 , , of house-cricket, to mount, S. 39 
 
 Glass cells, P. 33 
 
 ,, syringes, P. 37 
 Glasses for aquaria, P. 43 
 Glycerine and acetic acid fluid, R. 74 
 jelly, R. 64 
 ., preservative fluid, R. 79 
 Gold size cement, R. 68 
 
 ,, tests for, P. 222 
 Guano, &c., P. 195 
 
 Gum and glycerine for mounting, R. 3 
 ,, used for giving solidity to objects 
 
 before cutting sections, P. 156 
 ,, water (strong), R, 8 
 Gutta-percha cement, R. 4 
 
 HAIRS (animal), to mount, &c., P. 136 
 ,, (vegetable), to mount, &c., P. 137 
 
 Horns and hoofs, to make sections of, 
 P. 138 
 
 Holding screw, P. 5 
 
 How to apply heat to an object, P. 250, 
 
 42 
 
 ,, to catch podurae, P. 174 
 ,, to collect beetles, P. 162 
 ,, to collect insects, &c., P. 157 
 ,, to cover slides, S. 2 
 ,, to examine an unknown sub- 
 stance, P. 213 
 ,, to inject a frog, P. 139 
 ,, to keep an object moist, P. 250 
 ,, to make thin glass cells, S. 26 
 ,, to mount the columella of mosses, 
 
 S. 45 
 
 ,, to store small insects, P, 157 
 ,, to use a bottle for catching 
 
 insects, P. 166 
 ,, to use the pipette, P. 250 
 
 Human flea, to mount, S. 25 
 
 Hydrochloric acid, use of, P. 236 
 
 Hydrogen, how to make, R. 20 
 
 INDIA-RUBBER cement, R. 5 
 
 ,, cloth for damp places, 
 
 P. 163 
 Injecting fluid (blue opaque), R. 44 
 
 , , (blue transparent), R. 46 
 
 ,, (carmine), R. 41 
 
 (green), R. 39 
 (Prussian blue), R. 33 
 ,, (red opaque), K. 42 
 
214 
 
 INDEX. 
 
 Injecting fluid (white opaque), R. 45 
 ,, (yellow opaque), R. 43 
 
 Injection, process of, P. 138 
 Inorganic subtances, to analyse, P. 213 
 Insects mounted entire, P. 140 
 Instrument for holding slides, P. 38 
 Iodine, R. 54 
 
 ,, tests for, P. 226 
 
 use of, P. 243 
 Iron, tests for, P. 220 
 
 JUNCUS communis, section of, S. 8 
 
 LABELLING slides, P. 68 
 
 Lamp-black as a varnish, P. 85 
 
 Lamps, P. 54 
 
 Lead, tests for, P. 223 
 
 Liquor ammonia, use of, P. 244 
 
 List of re-agents, P. 233 
 
 Lithographic paper for drawings, P. 261 
 
 Local excursions, P. 179 
 
 Logwood staining, R. 36 
 
 Lung of a frog, to mount, S. 38 
 
 MACHINE for cutting rock sections, P. 35 
 Magnesium (magnesia), tests for, P. 219 
 Marine diatoms, P. 193 
 Matthews's turn-table, use of, P. 4, S . 4 
 Measurements (microscopic), 82 appen- 
 dix 
 
 Measuring thickness of thin glass, P. 39 
 Mercury, tests for, P. 225 
 Method of centring glass slips, S. 1 
 ,, of cutting cellular tissues, S. g 
 ,, of drying objects, P. 6 
 ,, of examination of insects, ani- 
 malculse, &c., under the 
 action of gas, P. 7 
 ,, of photographing objects, P. 29 
 Mica or talc, R. 55 
 Micro-fungi, how to collect, P. 167 
 Millon's test, R. 25 
 Mites, where to find, P. 200 
 Mosses, collection of, P. 175 
 ,, where to find, P. 197 
 Moths, how to catch, P. 182 
 Mounting by the dry transparent 
 
 method, P. 60 
 ,, crystals, S. 48 
 cuticles, S. 10, 30 
 
 Mounting desmids, S. 43 
 ,, diatoms, S. 4 
 ,, eggs of insects, S. 18 
 ,, foraminifera, S. 13 
 ,, in castor oil, S. 48 
 
 in fluid, S. 78 
 ,, in glycerine, S. 37 
 ,, in glycerine jelly, S. 40 
 ,, minute objects, P. 74 
 ,, on gutta-percha, P. 63 
 ,, opaque objects, P. 62 
 ,, palates, S. 19 
 pollens, &c. , S. 16, 20, P. 1 43 
 ,, raphides, S. 28 
 
 seeds, S. 17 
 
 ,, small insects, S. 25 
 ,, spines, S. 14 
 ,, starches, &c., S. 29 
 ,, with Canada balsam, P. 70 
 ,, with silicate of potass, S. 39 
 ,, zoophytes, &c., S. 42 
 Moveable board for microscope, P. 45 
 Miiller's hardening fluid, R. 38 
 Mustard, adulterations of, P. 254 
 
 NEUTRAL tint glass reflector used for 
 
 drawing, P. 30 
 New staining fluid, R. 35 
 Nitrate of barium, use of, P. 240 
 , , of silver, R. 30 
 ,, of silver, use of, P. 241 
 Nitric acid, use of, P. 235 
 Nitrogen, to prepare, R. 21 
 Note-book, use of, P. 165 
 
 Objects dissected in glycerine, P. 82 
 , , in fluid, P. 78 
 , , kept in their place by pressure, 
 
 gum, &c., P. 77 
 ,, mounted in cells, P. 73 
 , , mounted in paper varnish, P. 76 
 ,, mounted in resin, P. 75 
 
 Observing objects under action of heat, 
 P. 42 
 
 Oil of lemon, R. 53 
 
 Organic substances, to analyse, P. 213 
 
 Osmic acid solution of, R. 31 
 
 Oven for drying slides, P. 6 
 
 Oxalate of ammonia, use of, P. 242 
 
 Oxygen, to prepare, R. 19 
 
INDEX. 
 
 215 
 
 PALATE of periwinkle, S. 19 
 of whelk, S. 26 
 
 Palates, to dissect, P. 128 
 
 ,, to prepare and mount, P. 141 
 
 Parmelia parietina (a lichen), S. 23 
 
 Pepper, adulterations of, P. 252 
 
 Petals of flowers, to prepare and 
 mount, P. 142 
 
 Phosphates, to test for, P. 231 
 
 Pipette, use of, P. 32 
 
 Plan for storing and classifying slides, 
 P. 211 
 
 Podune, how to catch, P. 199 
 
 Polishing powder, R. 51 
 
 Pollen of bird's foot trefoil, S. 6 
 ,, of convolvulus, S. 20 
 
 Pollens, to mount, P. 143 
 
 Portable apparatus, P. 184 
 
 Postage of objects, P. 209 
 
 Potassium (potass), tests for, P. 216 
 
 Potato starch, S. 29 
 
 Preservative fluid, for insect dissec- 
 tions, R. 80 
 
 Pressure apparatus, P. 26 
 
 Proboscis of house-fly, S. 47 
 
 RALF'S liquid, R. 76 
 
 Raphides, how to mount, P. 144 
 
 ,, in onion, S. 28 
 Re-agents, P. 233 
 Removing grease from sections of 
 
 bone, S. 5 
 Retort stand, P. 18 
 
 Rock sections, preparation of, P. 35, 145 
 Rotatoria, where to find, P. 188 
 Roughly labelling specimens, P. 208 
 
 SAW used in cutting sections, P. 19 
 
 Scale of roach, S. 3 
 
 Scales of fish, to prepare and mount, 
 
 P. 147 
 
 ,, of insects, to mount, P. 148 
 ,, of plants, to mount, P. 146 
 
 Scalpels, &c., P. 48 
 
 Schultze's test, R. 27 
 
 Schulze's test, R. 28 
 
 Sealing wax varnish, R. 7 
 
 Sea water, for the preservation of 
 zoophytes, S. 42 
 
 Section cutters, P. 3 
 
 Section of human bone, S. 5 and 37 
 Seeds of red campion, S. 17 
 
 ,, sections of, to mount, c., P. 149 
 Separating glass tubes for pipettes, P. 16 
 Siliceous cement, R. 73 
 
 ,, cuticle of equisetum, S. 30 
 Silicon (silica), test for, P. 227 
 Silver, tests for, P. 224 
 Small insects under bark, P. 1 98 
 Soaking in turpentine, P. 72 
 
 ,, objects before mounting, P. 75 
 Sodium (soda), tests for, P. 216 
 Soldering rod, P. 55 
 Solution of potass, use of, P. 245 
 
 ,, of soda, use of, P. 246 
 Sphacellaria cirrhosa, for autherozoids, 
 
 P. 191 
 
 Spines of a brittle star-fish, S. 14 
 Spirit lamp, P. 23 
 Spiracle of water-beetle, S. 33 
 Spiracles of insects, dissection of, P. 128 
 Spore cases of a fern, S. 15 
 Spores and sporanges of brake-fern, S. 35 
 
 ,, of an equisetum, S. 7 
 Spring clips, P. 57 
 Starches, preparation of, P. 151 
 Stamens and pollen of mallow, S. 16 
 Staining fluid (blue), R. 29 
 
 ,, ,, (carmine), R. 47. 
 
 ,, (Turnbull's blue), R. 34 
 
 ,, tissues, P. 150 
 Storage of objects, P. 201, &c. 
 Sulphate of cadmium, R. 15 
 
 ,, of lime, S. 12 
 Sulphates, to test for, P. 229 
 Sulphuretted Hydrogen, R. 24 
 Sulphuric acid, P. 234 
 Syrup for mounting, R. 63 
 
 ,, useful for mounting, P. 89 
 
 TANNIN, solution of, R. 32 
 Tea, adulterations of, P. 257 
 Teeth, cutting sections of, P. 152 
 Test bottle, P. 9 
 Testing by electricity, P. 232 
 
 ,, the amount of moisture in 
 
 objects, S. 12 
 Test papers, use of, P. 249 
 Tests for calcium (lime), P. 218 
 , for carbonates, P. 228 
 
216 
 
 INDEX. 
 
 Tests for chloride, P. 230 
 ,, for chromic acid, E. 18 
 ,, for copper, P. 221 
 ,, for gold, P. 222 
 ,, for iodine, P. 226 
 ,, for iron, P. 220 
 ,, for lead, P. 223 
 ,, for magnesium (magnesia), P. 219 
 ,, for mercury (quicksilver), P. 225 
 ,, for phosphates, P. 231 
 ,, for potassium (potass), P. 216 
 ,, for silicon (silica or flint), P. 227 
 for silver, P. 224 
 ,, for sodium (soda), P. 217 
 ,, for sulphates, P. 229 
 Test tubes, P. 47 
 
 The examination of organic and in- 
 organic substances, P. 214 
 ,, use of arsenious acid, P. 88 
 ,, use of oiled silk, P. 159 
 Tin box used in mounting, P. 54 
 Tobacco, adulterations of, P. 258 
 To clean foraminifera from sand, P. 135 
 ,, clean waste balsam from slides, S. 25 
 ,, free zoophytes from sea salt, P. 66 
 ,, keep larva? and moths, P. 172 
 ,, make scales of the different powers, 
 
 P. 262 
 
 ,, obtain animal culse, P. 170 
 ,, render wood plastic, R. 67 
 'set' beetles, P. 157 
 ,, test an object by burning upon 
 
 platinum foil, P. 213 
 ,, test the adulterations of fabrics, 
 P. 251 
 
 Tongue of snail, S. 40 
 
 Tongues of insects, dissection of, P. 128 
 
 Tracheae of insects, to dissect, prepare, 
 
 and mount, P. 127, 153 
 Transverse section of oak, S. 9 
 ,, section of' rush, S. 8 
 Triangle for testing, P. 17 
 Trough used for observing circulation 
 
 of blood in tadpoles, P. 36 
 Typical slides, P. 62 
 
 USEFUL boxes for storage of objects, 
 
 P. 205 
 
 Useful cement, R. 72 
 Use of polarized light, P. 250 
 
 VALENTINE'S knife, P. 12 
 Valisneria, circulation in, P. 154 
 Vegetable ducts, P. 129 
 
 WASH bottle, P. 10 
 
 Washing tissues, P. 37 
 
 Water beetles, how to catch, P. 176 
 .,, fleas, how to collect, P. 171 
 ,, ,, where to find, P. 188 
 
 Wheat starch, S. 41 
 
 White cement, R. 78 
 ,, gutta percha, R. 66 
 
 Wing of cabbage butterfly, S. 1 
 
 Wood, sections of, P. 3, 155 
 
 Woulff's bottle, P. 15 
 
 ZOOPHYTES, how to kill, P. 177 
 
 where to find, P. 191 
 
 DICKINSON, STEAM PRINTER, HIGH STREET, 3IAIDSTONE. 
 
JNO. H. MARTIN, 
 
 MEMBER OF THE SOCIETY OF PUBLIC ANALYSTS, FELLOW 
 
 OF THE SOCIETY OF ARTS, AUTHOR OF "MANUAL OF 
 
 MICROSCOPIC MOUNTING," "MICROSCOPIC OBJECTS," &c. 
 
 mo 
 
 YORK CHAMBERS, 
 
 YORK BUILDINGS, 
 ADELPHI, 
 
 LONDON, W.C. 
 
 Chemical and Microscopical Analyses performed, Lessons given 
 in Microscopy, Food Analysis, &c. 
 
 TERMS ON APPLICATION. 
 
 The author of the above works having had great and varied 
 experience both in Microscopy and Chemistry, can be consulted 
 on either department by letter, or personally, at the hours stated. 
 
 LABORATORY HOURS, 10 to 13 to 5. 
 
 ANALYTICAL FEES, 
 
 s. d. 
 
 Arsenic Testing for in 
 Confectionery, Paper- 
 hanging, c. o 10 
 
 Beer For Alcohol & Acidity o 10 
 ,, Complete Analysis ... 2 2 
 
 Pood Chemical and Micro- 
 scopical examination 
 for adulterations 6/8 to 2 2 
 
 Iron Ore Complete analysis 5 5 
 ,, Commercial Analysis 2 2 
 
 Linseed Cake Commer- 
 cial Analysis I I o 
 
 Paper Microscopical Exam- 
 ination, also Fibres 
 fit for o 10 6 
 
 Soils Complete Analysis ... 5 5 O 
 
 ,, Estimation of Lime, 
 Phosphoric Acid and 
 Alkalies i I o 
 
 Superphosphate Com- 
 mercial Analysis ... I I o 
 
 s. d. 
 6 o 
 
 Toxicological Examina- 
 tion ... 2 2 o to 6 
 
 Urine Analysis for Albu- 
 men or Sugar o 10 6 
 
 , , Complete Chemical 
 and Microscopical 
 Analysis ... 220 
 
 Water Estimation of hard 
 ness, permanent and 
 temporary, showing 
 its fitness for Steam 
 Boilers o 10 o 
 
 ,, Opinion as to its qual- 
 ity, giving also solid 
 matter, Chlorine, hard- 
 ness, &c i i o 
 
 ,, Complete Analysis 
 showing its fitness for 
 drinking purposes, &c I 10 6 
 
 ,, Complete Analysis 
 
 for Brewers 33 
 
 Wine Analysis 1 0/6 to I I o 
 
LONDON, NEW BURLINGTON STREET 
 FEBRUARY, 1879. 
 
 A LIST 
 
 OF 
 
 MESSRS CHURCHILL'S 
 WORKS 
 
 ON 
 
 CHEMISTRY, MATERIA MEDICA, 
 
 PHARMACY, BOTANY, 
 
 THE MICROSCOPE, 
 
 AND 
 
 OTHER BRANCHES OF SCIENCE 
 
INDEX 
 
 Beasley's Pocket Formulary ... 
 Do. Druggist's Receipt Book ... 
 Do. Book of Prescriptions 
 
 Berkley's Manual of Botany 
 
 Bentley and Trimen's Medicinal Plants 
 Bernay's Notes for Students ... 
 Binz's Elements of Therapeutics 
 
 Bloxam's Chemistry 
 
 Do. Laboratory Teaching 
 Bowman's Practical Chemistry 
 Bradley's Comparative Anatomy and 
 
 Physiology ... 
 Brooke's Natural Philosophy 
 
 Brown's Analytical Tables 
 
 Carpenter's Microscope and its Reve- 
 lations ... 
 
 Chauveau's Comparative Anatomy ... 
 Clowes' Practical and Analytical Che- 
 mistry 
 
 Cooley's Cyclopaedia of Receipts 
 Dunglison's Medical Lexicon 
 Ewart's Poisonous Snakes of India... 
 Fayrer's Poisonous Snakes of India... 
 
 Do. Royal Tiger of Bengal 
 Fownes' and Watts' Chemistry 
 Fox's Ozone and Antozone ... 
 Frankland's How to Teach Chemistry 
 Fresenius' Chemical Analysis 
 Galloway's First Step in Chemistry... 
 Do. Qualitative Analysis 
 
 Do. Chemical Tables 
 
 Greene's Tables of Zoology ... 
 Hardwich's Photography, by Dawson 
 Hehner and Angell's Butter Analysis 
 Huxley's Anatomy of Vertebrates ... 
 Do. Anatomy of Invertebrates... 
 Do. Classification of Animals . . . 
 Kay-Shuttleworth's Modern Chemistry 
 Kensington's Chemical Composition 
 
 of Foods 
 Kohlrausch's Physical Measurements 
 
 Kollmyer's Chemia Coartata 
 
 Lescher's Elements of Pharmacy 
 
 PAGE 
 
 x 
 
 X 
 X 
 
 xi 
 xi 
 v 
 vii 
 iii 
 iii 
 iv 
 
 xii 
 
 xiv 
 
 iv 
 
 xi 
 xii 
 
 iv 
 
 vi 
 
 XV 
 
 xiii 
 
 xiii 
 
 xiii 
 
 iii 
 
 xv 
 
 iv 
 
 iv 
 
 v 
 
 v 
 
 v 
 
 xiii 
 
 xv 
 
 v 
 
 xiii 
 
 xiii 
 
 xiii 
 
 v 
 
 V 
 
 xiv 
 iv 
 
 viii 
 
 PAGE 
 
 Marsh's Section Cutting xii 
 
 Martin's Microscopic Mounting ... xi 
 Mayne's Medical Vocabulary ... xv 
 Microscopical Journal (Quarterly) ... xii 
 Ord's Comparative Anatomy ... xiii 
 Owen's Tables of Materia Medica ... viii 
 Pereira's Selecta e Pnescriptis ... viii 
 Pharmaceutical Journal and Transac- 
 tions x 
 
 Phillips' Materia Medica vii 
 
 Prescriber's Pharmacopoeia ... ... viii 
 
 Price's Photographic Manipulation ... xiv 
 
 Proctor's Practical Pharmacy ... viii 
 
 Rod well's Natural Philosophy ... xiv 
 
 Royle's Materia Medica vii 
 
 Shea's Animal Physiology ... ... xiv 
 
 Smith's Pharmaceutical Guide ... ix 
 
 Southall's Materia Medica vii 
 
 Squire's Companion to the Pharma- 
 copoeia ix 
 
 Squire's Hospital Pharmacopoeias ... ix 
 
 Steggall's First Lines for Chemists ... ix 
 
 Stocken's Dental Materia Medica ... viii 
 
 Stowe's Toxicological Chart ... ... ix 
 
 Sutton's Volumetric Analysis ... v 
 
 Taylor on Poisons ... ix 
 
 Thorowgood's Materia Medica .., vii 
 
 Tidy's Modern Chemistry ... ... iv 
 
 Do. London Water Supply ... xv 
 
 Tuson's Veterinary Pharmacopoeia ... xi 
 
 Vacher's Primer of Chemistry ... iv 
 
 Valentin's Inorganic Chemistry ... vi 
 
 Do. Qualitative Analysis ... vi 
 
 Do. Chemical Tables ... ... vi 
 
 Wagner's Chemical Technology ... vi 
 Wahltuch's Dictionary of Materia Me- 
 dica ... ... ... ... ... vii 
 
 Whalley's Human Eye xiv 
 
 Wilson's Zoology ... xiv 
 
 Wittstein's Pharmaceutical Chemistry, 
 
 by Darby x 
 
 Wythe's Microscopist ... ... xii 
 
 Year Book of Pharmacy ... ... x 
 
 %* The Works advertised in this Catalogue may be obtained throtigh any Bookseller 
 in the United Kingdom, or direct Jrom the Publishers, on Remittance being made. 
 
A LIST OF 
 
 Messrs CHURCHILL'S WORKS 
 ON SCIENCE 
 
 C L. Bloxam 
 
 CHEMISTRY, INORGANIC and ORGANIC. 
 
 With Experiments. By CHARLES L. BLOXAM, Professor of Chemistry in 
 King's College, London ; Professor of Chemistry in the Department for 
 Artillery Studies, Woolwich. Third Edition. With 295 Engravings. 
 
 [8vo, 1 6s. 
 
 \* It has been the author's endeavour to produce a Treatise on Chemistry sufficiently 
 comprehensive for those studying the science as a branch of general education, and one 
 which a student may peruse with advantage before commencing his chemical studies at 
 one of the colleges or medical schools, where he will abandon it for the more advanced 
 work placed in his hands by the professor. The special attention devoted to Metallurgy 
 and some other branches of Applied Chemistry renders the work especially useful to those 
 who are being educated for employment in manufacture. 
 
 " Professor Bloxam has given us a most 
 excellent and useful practical treatise. His 
 666 pages are crowded with facts and expe- 
 riments, nearly all well chosen, and many 
 quite new, even to scientific men. . . It 
 
 is astonishing how much information he often 
 conveys in a few paragraphs. We might 
 quote fifty instances of this." Chemical 
 
 By the same Author 
 
 LABORATORY TEACHING: Or, Progressive Exercises 
 in Practical Chemistry, with Analytical Tables. Third Edition. With 
 89 Engravings .... Crown 8vo, 55. 6d. 
 
 \* This work is intended for use in the chemical laboratory by those who are com- 
 mencing the study of practical chemistry. It does not presuppose any knowledge of 
 chemistry on the part of the pupil, and does not enter into any theoretical speculations. 
 It dispenses with the use of all costly apparatus and chemicals, and is divided into 
 separate exercises or lessons, with examples for practice, to facilitate the instruction of large 
 classes. The method of instruction here followed has been adopted by the author, 
 after twenty-three years' experience as a teacher in the laboratory. 
 
 G. Fownes and Henry Watts 
 
 MANUAL OF CHEMISTRY. By G. FOWNES, FR.S. 
 Edited by HENRY WATTS, B.A., F.R.S. Twelfth Edition. 
 
 Vol. I. Physical and Inorganic Chemistry. With 154 Engravings 
 
 and Coloured Plate of Spectra . . Crown 8vo, 8s. 6d. 
 
 Vol. II. Chemistry of Carbon Compounds, or Organic Chemistry. 
 
 with Engravings .' . . Crown 8vo, los. 
 
iv MESSRS CHURCHILL'S SCIENTIFIC WORKS 
 
 Remigius Fresenius 
 
 QUALITATIVE ANALYSIS. By C. REMIGIUS FRESENIUS. 
 
 Edited by ARTHUR VACHER. Ninth Edition, with Coloured Plate of 
 Spectra and 47 Engravings . . . 8vo, 125. 6d. 
 
 By the same Author 
 
 QUANTITATIVE ANALYSIS. Edited by ARTHUR VACHER. 
 Seventh Edition. Vol. I. With 106 Engravings. . . 8vo, 155, 
 
 Arthur Vacher 
 
 A PRIMER OF CHEMISTRY, Including Analysis. 
 By ARTHUR VACHER .... iSmo, is. 
 
 Frank Clowes 
 PRACTICAL CHEMISTRY AND QUALITATIVE 
 
 INORGANIC ANALYSIS. By FRANK CLOWES, D. Sc. Lond., F.C.S. 
 Lond. and Berlin. Second Edit. With 47 Engravings. Crown 8vo, 73. 6d. 
 %* This work is an Elementary Treatise specially adapted for use in the Laboratories 
 of Schools and Colleges, and by beginners. 
 
 o 
 
 John E. Bowman and C. L. Bloxam 
 
 PRACTICAL CHEMISTRY, Including Analysis. 
 
 By JOHN E. BOWMAN and C. L. BLOXAM. Seventh Edition. With 
 
 98 Engravings .... Fcap 8vo, 6s. 6d. 
 
 %* In this edition the entire Analytical Course has been reduced to a tabular form, 
 
 and symbols and equations have been freely used. The intention of the work is to 
 
 furnish to the beginner a text-book of the practical minutice of the laboratory. The 
 
 various processes employed in analysis, or which have been devised for the illustration 
 
 of the principles of the science, are explained in language as simple as possible. 
 
 o 
 
 J. Campbell Brown 
 
 ANALYTICAL TABLES for STUDENTS of PRACTICAL 
 CHEMISTRY. By J. CAMPBELL BROWN, D.Sc. Lond., F.C.S. 
 
 [8vo, 2s. 6d. 
 
 C. Meymott Tidy 
 
 A HANDBOOK OF MODERN CHEMISTRY, Inorganic 
 and Organic. For the Use of Students. By CHARLES MEYMOTT TIDY, 
 M.B., F.C.S., Professor of Chemistry at the London Hospital. 8vo, i6s. 
 
 Edward Frankland 
 
 HOW TO TEACH CHEMISTRY: Hints to Science 
 Teachers and Students. Six Lectures by EDWARD FRANKLAND, D.C.L., 
 F.R.S., Summarised and Edited by GEORGE CHALONER, F.C.S. With 
 47 Engravings . . . Crown 8vo, 35. 6d. 
 
 A. H. Kollmyer 
 
 CHEMIA COARTATA; or, the Key to Modern Chemistry. 
 By A. H. KOLLMYER, A.M., M.D., Professor of Materia Medica and 
 Therapeutics at Montreal. New Edition . . 8vo, 73. 6d. 
 
MESSRS CHURCHILL'S SCIENTIFIC WORKS 
 
 Robert Galloway 
 
 THE FIRST STEP IN CHEMISTRY: A New Method for 
 Teaching the Elements of the Science. By ROBERT GALLOWAY, Professor 
 of Applied Chemistry in the Royal College of Science for Ireland. Fourth 
 Edition, with Engravings . . . Fcap 8vo, 6s. 6d. 
 
 By the same Author 
 
 A MANUAL OF QUALITATIVE ANALYSIS. 
 Fifth Edition, with Engravings . . Post 8vo, 8s. 6d. 
 
 Also 
 
 CHEMICAL TABLES ACCORDING TO THE OLD 
 NOTATION. On Five Large Sheets, for School and Lecture Rooms. 
 Second Edition . . . The Set, 45. 6d. 
 
 E. T. Kensington 
 
 CHEMICAL COMPOSITION OF FOODS, WATERS, 
 SOILS, MINERALS, MANURES, AND MISCELLANEOUS SUB- 
 STANCES. Compiled by E. T. KENSINGTON, F.C.S., formerly Chief 
 Assistant to Thomas Anderson, M.D., late of the University of Glasgow. 
 
 [Fcap 8vo, 55. 
 
 U. J. Kay-Shuttleworth 
 
 FIRST PRINCIPLES OF MODERN CHEMISTRY. 
 By Sir U. J. KAY-SHUTTLEWORTH, Bart., M.P. Second Edition. 
 
 Crown 8vo, 45. 6d. 
 o 
 
 Francis Sutton 
 HANDBOOK OF VOLUMETRIC ANALYSIS; 
 
 or, the Quantitative Estimation of Chemical Substances by Measure applied 
 to Liquids, Solids, and Gases. By FRANCIS SUTTON, F.C S., Public 
 Analyst for the County of Norfolk. Third Edition. With 74 Engravings. 
 
 [8vo, 155. 
 
 %* This work is adapted to the requirements of pure Chemical Research, Pathological 
 Chemistry, Pharmacy, Metallurgy, Manufacturing Chemistry, Photography, etc., and for 
 the Valuation of Substances used in Commerce, Agriculture, and the Arts. 
 
 "Mr. Sutton has rendered an essential service by the compilation of his work.'" 
 Chemical News. 
 
 
 
 A. J. Bernays 
 
 NOTES FOR STUDENTS IN CHEMISTRY: Being a 
 Syllabus of Chemistry, compiled mainly from the Manuals of MILLER, 
 FOWNES- WATTS, WURZ, and SCHORLEMMER. By ALBERT J. BERNAYS, 
 Ph. D., Professor of Chemistry at St. Thomas's Hospital. Sixth Edition. 
 
 Fcap. 8vo, 3s. w 6d. 
 
 Otto Hehner and Arthur Angell 
 
 BUTTER ; Its Analysis and Adulterations, specially treating on 
 the Detection and Determination of Foreign Fats. By OTTO HEHNER, 
 F.C.S., Public Analyst for the Isle of Wight, and ARTHUR ANGELL, 
 F.R.M.S., Public Analyst for the County of Southampton. Second Edition. 
 Entirely re-written and augmented. . . [Crown Svo, 35. 6d. 
 
vi MESSRS CHURCHILL'S SCIENTIFIC WORKS 
 
 W. G. Valentin 
 
 INTRODUCTION TO INORGANIC CHEMISTRY. By 
 WM. G. VALENTIN, F.C.S., Principal Demonstrator of Practical Che- 
 mistry in the Royal School of Mines and Science Training Schools, 
 South Kensington. Third Edition. With 82 Engravings . 8vo, 6s. 6d. 
 
 Also 
 QUALITATIVE CHEMICAL ANALYSIS. Fourth Edition. 
 
 With 19 Engravings . 8vo, 75. 6d. 
 
 Also 
 
 TABLES FOR THE QUALITATIVE ANALYSIS OF 
 SIMPLE AND COMPOUND SUBSTANCES, both in the Dry and Wet 
 Way. On indestructible paper . . . 8vo, 2s. 6d. 
 
 Also 
 
 CHEMICAL TABLES FOR THE LECTURE ROOM AND 
 LABORATORY. In five large sheets. 5s. 6d. 
 
 R. Wagner and W. Crookes 
 
 HANDBOOK OF CHEMICAL TECHNOLOGY. By 
 RUDOLF WAGNER, Ph.D., Professor of Chemical Technology at the 
 University of Wurtzburg. Translated and Edited from the Eighth German 
 Edition, with Extensive Additions, by WILLIAM CROOKES, F.R.S. With 
 336 Engravings ....... 8vo, 255. 
 
 * x* The design of this work is to show the application of the science of chemistry to 
 the various manufactures and industries. The subjects are treated of in eight divisions, 
 as follows : I. Chemical Metallurgy, Alloys, and Preparations made and obtained from 
 Metals. 2. Crude Materials and Products of Chemical Industry. 3. Glass, Ceramic 
 Ware, Gypsum, Lime, Mortar. 4. Vegetable Fibres. 5. Animal Substances. 6. Dye- 
 ing and Calico Printing. 7. Artificial Light. 8. Fuel and Heating Apparatus. 
 
 " Full and exact in its information on 
 almost every point." Engineer. 
 
 " This book will permanently take its 
 place among our manuals." Nature. 
 
 " Mr. Crookes deserves praise, not only 
 for the excellence of his translation, but 
 also for the original matter he has added." 
 American Journal of Science and Arts. 
 
 R. V. Tuson 
 
 COOLEY'S CYCLOPEDIA OF PRACTICAL 
 RECEIPTS, AND COLLATERAL INFORMATION IN THE ARTS, 
 MANUFACTURES, PROFESSIONS, AND TRADES : Including 
 Pharmacy and Domestic Economy and Hygiene. Designed as a Com- 
 prehensive Supplement to the Pharmacopoeias and General Book of 
 Reference for the Manufacturer, Tradesman, Amateur, and Heads of 
 Families. Sixth Edition, Revised and Rewritten by Professor RICHARD 
 V. TUSON, F.I.C., F.C.S., assisted by several Scientific Contributors. 
 Parts i to 8 (March to January, 1879). Each 2s. 6d. 
 
 %* It has been considered desirable to bring out the sixth edition of this work in 
 
 monthly parts. Each part will consist of 112 pzges, and the book will be compteted in 
 
 about 15 monthly parts at 2s. 6d. each. 
 
 The new edition, which will exceed the last by some 400 pages, will contain a greatly 
 
 increased number of receipts culled from the most reliable English and foreign journals ; 
 
 numerous Articles on Applied Chemistry, Phaimacy, Hygiene, Human, and Veterinary 
 
 Medicine, &c., will be added ; many of the old articles will be extended ; and, where 
 
 desirable, the text will be illustrated by woodcuts. 
 
MESSRS CHURCHILL'S SCIENTIFIC WORKS vii 
 
 y. Forbes Royle and John Harley 
 ROYLE'S MANUAL OF MATERIA MEDICA AND 
 
 THERAPEUTICS. Sixth Edition. By JOHN HARLEY, M.D. With 
 139 Engravings. .... Crown Svo, 155. 
 
 "This Manual is, to our minds, unrivalled I and completeness of information." British 
 in any language for condensation, accuracy, | Medical Journal. 
 
 C. Bins 
 
 THE ELEMENTS OF THERAPEUTICS. A Clinical Guide 
 to the Action of Drugs. By C. BlNZ, M.D., Professor of Pharmacology in 
 the University of Bonn. Translated and Edited with Additions, in 
 Conformity with the British and American Pharmacopoeias, by EDWARD 
 I. SPARKS, M.A., M B. Oxon., formerly Radcliffe Travelling Fellow. 
 
 [Crown Svo, 8s. 6d. 
 *** Practically, this translation represents a new edition, a considerable amount of 
 
 new matter which did not appear in the fifth German edition having been added by 
 
 Professor Binz, and a number of errors which occurred in the latter having been corrected. 
 
 Nearly the whole of the proof sheets have been read and revised by Professor Binz. 
 
 W. Southall 
 
 THE ORGANIC MATERIA MEDICA OF THE BRITISH 
 
 PHARMACOPCEIA SYSTEMATICALLY ARRANGED : Together 
 with Brief Notices of the Remedies contained in the Indian and United 
 States Pharmacopoeias. By W. SOUTHALL, F.L.S. . Post Svo, 2s. 6d. 
 
 J. C. Thorowgood 
 THE STUDENT'S GUIDE TO MATERIA MEDICA 
 
 Including the New Additions to the British Pharmacopoeia. By JOHN 
 C. THOROWGOOD, M.D. Lond., Lecturer on Materia Medica at the Middle- 
 sex Hospital. With Engravings . . Fcap Svo, 6s. 6d. 
 " Students can hardly hope fora more serviceable text-book." Practitioner. 
 
 C. D. F. Phillips 
 
 MATERIA MEDICA AND THERAPEUTICS : VEGE- 
 TABLE KINGDOM. By CHARLES D. F. PHILLIPS, M.D. Svo, 155. 
 
 " It is the great distinction of this book that an amount of space is given in it to care- 
 ful discussion of the physiological and the therapeutical actions of drugs greater than has 
 been given in any previous English text-book of Materia Medica." Practitioner. 
 
 Adolphe Wahltuch 
 
 A DICTIONARY OF MATERIA MEDICA AND THERA- 
 PEUTICS. By ADOLPHE WAHLTUCH, M.D. . . Svo, ics. 6d. 
 
 *** The purpose of this work is to give a tabular arrangement of all drugs specified in 
 the British Pharmacopoeia of 1867. Every table is divided into six parts : (i) The 
 Name and Synonyms ; (2) Character and Properties or Composition ; (3) Physiological 
 Effects and Therapeutics ; (4) Form and Doses ; (5) Preparations ; (6) Prescriptions. 
 Other matter elucidatory of the Pharmacopoeia is added to the work. 
 
 " A very handy book," Lancet. 
 
viii MESSRS CHURCHILL'S SCIENTIFIC WORKS 
 
 7. Stocken 
 
 ELEMENTS OF DENTAL MATERIA MEDICA AND 
 THERAPEUTICS, WITH PHARMACOPCEIA. By JAMES STOCKEN, 
 L.D.S.R.C.S., Lecturer on Dental Materia Medica and Therapeutics, and 
 Dental Surgeon to the National Dental Hospital. Second Edition, 
 
 Fcap. 8vo, 6s. 6d. 
 
 Isambard Owen 
 TABLES OF MATERIA MEDICA. Third Edition. 
 
 [Crown 8vo, 2s. 6d. 
 
 Jonathan Pereira 
 
 SELECTA E PR.ESCRIPTIS : Containing Lists of the Terms, 
 Phrases, Contractions, and Abbreviations used in Prescriptions, with Ex- 
 planatory Notes ; the Grammatical Construction of Prescriptions ; Rules 
 for the Pronunciation of Pharmaceutical Terms ; a Prosodiacal Vocabulary 
 of the Names of Drugs, &c. ; and a Series of Abbreviated Prescriptions 
 illustrating the use of the preceding terms. To which is added a Key, con- 
 taining the Prescriptions in an Unabbreviated Form, with a Literal Trans- 
 lation for the Use of Medical and Pharmaceutical Students. By JONATHAN 
 PEREIRA, M.D., F.R.S. Sixteenth Edition .... 32mo, 53. 
 
 THE PRESCRIBER'S PHARMACOPCEIA : The Medicines 
 arranged in Classes according to their Action, with their Composition 
 and Doses. By A PRACTISING PHYSICIAN. Fifth Edition. 
 
 [Fcap i6mo, cloth, 2s. 6d.; roan, with flap and elastic band, 33. 6d. 
 
 B* S. Proctor 
 
 LECTURES ON PRACTICAL PHARMACY. 
 
 By BARNARD S. PROCTOR, Lecturer on Pharmacy at the College of Medi- 
 cine, Newcastle-on-Tyne. With 43 Engravings and 32 Plates, containing 
 Fac-Simile Prescriptions 8vo, 125. 
 
 CONTENTS 
 
 Drying Comminution Solution Crystallisation Precipitation Diffusion in Liquids, 
 Dialysis, Osmosis, &c. Evaporation, Boiling, Fusion, and Calcination Distillation and 
 Sublimation Filtration and Percolation Official Pharmacy Official Liquors or Solu- 
 tionsOfficial Infusions and Decoctions Extracts Spirits, Tinctures, Wines, Vinegars, 
 Liniments Official Products of Distillation and Sublimation Official Products of Fusion 
 Official Saline Preparations, &c., Crystallised, Precipitated, Scaled, or Granulated 
 Complex Processes Dispensing Reading Autograph Prescriptions Pills Powders, 
 Ointments, Plasters, Suppositories, &c. Qualitative Tests of the Pharmacopoeia Quan- 
 titative Testing of the Pharmacopoeia Pharmacy of Special Drugs. 
 
 " A good specimen of a treatise on Chemistry as applied to a special art." Chemical 
 News. 
 
 
 
 F. Harwood Lescher 
 
 THE ELEMENTS OF PHARMACY: a Guide to the Prin- 
 cipal Points in Materia Medica, Botany, Chemistry, Pharmacy, Prescrip- 
 tions, and Dispensing. By F. HARWOOD LESCHER. Fifth Edition 
 
 [Royal 8vo, 73. 6d. 
 
MESSRS CHURCHILL'S SCIENTIFIC WORKS ix 
 
 J. B. Smith 
 
 PHARMACEUTICAL GUIDE TO THE FIRST AND 
 SECOND EXAMINATIONS. By JOHN BARKER SMITH. Second 
 Edition ....... Crown 8vo, 6s. 6d. 
 
 FIRST AND SECOND EXAMINATIONS 
 
 LATIN GRAMMAR FRACTIONS METRIC SYSTEM MATERIA MEDICA BOTANY 
 PHARMACY CHEMISTRY PRESCRIPTIONS. 
 
 John Steggall 
 
 FIRST LINES FOR CHEMISTS AND DRUGGISTS 
 
 preparing for Examination at the Pharmaceutical Society. By JOHN 
 STEGGALL, M.D. Third Edition i8mo, 35. 6d. 
 
 CONTENTS 
 
 Notes on the British Pharmacopoeia, the 
 Substances arranged alphabetically. 
 
 Table of 1'rcparations, containing Opium, 
 Antimony, Mercury, and Arsenic. 
 
 Classification of Plants. 
 
 Thermometers. 
 Specific Gravity. 
 Weights and Measures. 
 Questions on Pharmaceutical Chemistry 
 and Materia Medica. 
 
 Peter Squire 
 
 COMPANION TO THE BRITISH PHARMACOPOEIA 
 
 (latest Edition), comparing the strength of its various preparations with 
 those of the United States, and other Foreign Pharmacopoeias, to which 
 are added Non-official Preparations, and Practical Hints on Prescribing ; 
 also a Tabular Arrangement of Materia Medica for Students, and a Con- 
 cise Account of the Principal Spas of Europe. By PETER SQUIRE, late 
 President of the Pharmaceutical Society, assisted by his Sons P.W. SQUIRE 
 and A. H. SQUIRE. Eleventh Edition .... 8vo, los. 6d. 
 
 By the same Author 
 
 PHARMACOPOEIAS OF THE LONDON HOSPITALS. 
 Third Edition. Fcap 8vo, 6s. 
 
 *** Mr. SQUIRE has collected all the Formulse used in twenty-two of the principal 
 Hospitals of London, and arranged. them in groups of mixtures, gargles, &c., &c. These 
 Formulae were revised and approved by the medical staff of each of the Hospitals, and 
 may therefore be taken as an excellent guide to the medical practitioner, both as to dose 
 and best menstruum in prescribing. 
 
 William Stoive 
 
 A TOXICOLOGICAL CHART, Exhibiting at one view the 
 Symptoms, Treatment^ and Mode of Detecting the Various Poisons, 
 Mineral, Vegetable, and Animal. To which are added concise Directions 
 for the Treatment of Suspended Animation. By WILLIAM STOWE, 
 M.R.C.S.E. Thirteenth Edition .... Sheet, 2s. ; Roller, 53. 
 
 Alfred S. Taylor 
 
 POISONS IN RELATION TO MEDICAL JURIS* 
 PRUDENCE AND MEDICINE. By ALFRED S. TAYLOR, M.D., F.R.S., 
 Professor of Medical Jurisprudence to Guy's Hospital. Third Edition, with 
 104 Engravings Crown 8vo, i6s* 
 
MESSRS CHURCHILL'S SCIENTIFIC WORKS 
 
 Henry Beasley 
 THE POCKET FORMULARY AND SYNOPSIS 
 
 OF THE BRITISH AND FOREIGN PHARMACOPOEIAS : Compris- 
 ing Standard and approved Formulae for the Preparations and Compounds 
 employed in Medical Practice. By HENRY BEASLEY. Tenth Edition. 
 
 [i8mo, 6s. 6d. 
 By the same Author 
 
 THE DRUGGIST'S GENERAL RECEIPT-BOOK: 
 Comprising a Copious Veterinary Formulary, Numerous Recipes in 
 Patent and Proprietary Medicines, Druggists' Nostrums, &c. ; Perfumery, 
 and Cosmetics ; Beverages, Dietetic Articles and Condiments ; Trade 
 Chemicals ; Scientific Processes ; and an Appendix of Useful Tables. 
 Eighth Edition i8mo, 6s. 6d. 
 
 Also 
 
 THE BOOK OF PRESCRIPTIONS : Containing 3,107 Pre- 
 scriptions collected from the Practice of the most eminent Physicians and 
 Surgeons, English and Foreign. With an Index of Diseases and Remedies. 
 Fifth Edition i8mo, 6s. 6d. 
 
 "Mr. Beasley's 'Pocket Formulary,' 
 1 Druggist's Receipt-Book,' and ' Book of 
 Prescriptions' form a compact library of 
 
 reference admirably suited for the dispens- 
 ing desk." Chemist and Druggist. 
 
 G. C. Wittstem 
 
 PRACTICAL PHARMACEUTICAL CHEMISTRY: An 
 Explanation of Chemical and Pharmaceutical Processes ; with the Methods 
 of Testing the Purity of the Preparations, deduced from Original Experi- 
 ments. By Dr. G. C. WITTSTEIN. Translated from the Second German 
 
 Edition by STEPHEN DARBY . i8mo, 6s. 
 
 " It would be impossible too strongly to recommend this work to the beginner, for the 
 completeness of its explanations, by following which he will become well grounded 
 in practical chemistry." From the Introduction by Dr> Buchner, 
 
 THE PHARMACEUTICAL JOURNAL AND TRANSAC- 
 TIONS. Published weekly Price 4d. 
 
 THE YEAR-BOOK OF PHARMACY: Containing the 
 Proceedings at the Yearly Meeting of the British Pharmaceutical Con- 
 ference, and a Report on the Progress of Pharmacy, which includes notices 
 of all Pharmaceutical Papers, new Processes, Preparations, and Formulae 
 published throughout the world. Published annually in December. 
 
 [8vo, 1870, '71, '7273. 6d. each ; 1873, '74, '75, '76, '77, '78103. each* 
 
MESSRS CHURCHILL'S SCIENTIFIC WORKS xi 
 
 R. V. Tuson 
 
 A PHARMACOPOEIA, INCLUDING THE OUTLINES OF 
 MATERIA MEDICA AND THERAPEUTICS, for the Use of Prac- 
 titioners and Students of Veterinary Medicine. By RICHARD V. TUSON, 
 F.C.S., Professor of Chemistry and Materia Medica at the Royal 
 Veterinary College. Third Edition . . Post 8vo. [In the Press. 
 
 "Not only practitioners and students of 
 veterinary medicine, but chemists and 
 druggists will find that this book supplies a 
 
 want in veterinary literature." Chemist 
 and Druggist. 
 
 Robert Bentley 
 
 A MANUAL OF BOTANY: Including the Structure, Func- 
 tions, Classifications, Properties, and uses of Plants. By ROBERT 
 BENTLEY, F.L.S., Professor of Botany, King's College, and to the Pharma- 
 ceutical Society. Third Edition, with 1,138 Engravings. Crown 8vo, 143. 
 "As the standard manual of botany its position is undisputed." Chemist and 
 Druggist. 
 
 Robert Bentley arid Henry Trimen 
 
 MEDICINAL PLANTS: being Descriptions with Original 
 Figures of the Principal Plants employed in Medicine, and an Account 
 of their Properties and Uses. By ROBERT BENTLEY, F.L.S., Professor 
 of Botany in King's College, and to the Pharmaceutical Society ; and 
 HENRY TRIMEN, M.B., F.L.S., Lecturer on Botany in St. Mary's 
 Hospital Medical School. In about 42 Monthly Parts, each containing 
 8 Coloured Plates. Parts I. to XXXVII. issued since October, 1875, 55. each. 
 %* A Prospectus and Specimen Plate will be sent on application. 
 
 W. B. Carpenter 
 
 THE MICROSCOPE AND ITS REVELATIONS. By 
 W. B. CARPENTER, M.D., F.R.S. Fifth Edition, with more than 500 
 Engravings . . . Crown 8vo, 155. 
 
 %* The author has aimed to combine within a moderate compass that information in 
 regard to the use of his instrument and its appliances, which is most essential to the 
 working microscopist, with such an account of the objects best fitted for his study as may 
 qualify him to comprehend what he observes, and thus prepare him to benefit science, 
 whilst expanding and refreshing his own mind. 
 
 7. H. Martin 
 
 A MANUAL OF MICROSCOPIC MOUNTING; with Notes 
 on the Collection and Examination of Objects. By JOHN H. MARTIN, 
 Member of the Society of Public Analysts, author of " Microscopic Objects." 
 Second Edition. With 150 Engravings .... 8vo, 75. 6d. 
 ** The aim of this work is to supply the student with a concise manual of the prin- 
 ciples of microscopic mounting, and to assist his progress in the manual dexterity, as far 
 as illustrations and words render it possible, necessary in their application. 
 
xii MESSRS CHURCHILL'S SCIENTIFIC WORKS 
 
 Dr. Sylvester Marsh 
 
 SECTION CUTTING : a Practical Guide to the Preparation 
 and Mounting of Sections for the Microscope, special prominence being 
 given to the subject of Animal Sections. By Dr. SYLVESTER MARSH, 
 With Engravings Fcap. 8vo, 2s. 6d. 
 
 THE QUARTERLY JOURNAL OF MICROSCOPICAL 
 
 SCIENCE. (Established in 1852.) Edited by E. RAY LANKESTER, M.A., 
 F.R.S., Professor of Zoology and Comparative Anatomy in University 
 College, London ; W. ARCHER, F.R.S., M.R.I.A., F. M. BALFOUR, M.A., 
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 MANUAL OF COMPARATIVE ANATOMY AND 
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MESSRS CHURCHILL'S SCIENTIFIC WORKS xiii 
 
 J. Fayrer 
 
 THE THANATOPHIDIA OF INDIA; being a Description 
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 NOTES ON COMPARATIVE ANATOMY: a Syllabus of 
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 and Lecturer in its Medical School Crown 8vo, 55. 
 
xiv MESSRS CHURCHILL'S SCIENTIFIC WORKS 
 
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MESSRS CHURCHILL'S SCIENTIFIC WORKS xv 
 
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 many new methods and materials which 
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 MEDICAL LEXICpN: A DICTIONARY OF MEDICAL 
 
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 and Terms of Anatomy, Physiology, Pathology, Hygiene, Therapeutics, 
 Pharmacology, Pharmacy, Surgery, Obstetrics, Medical Jurisprudence, and 
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 Empirical, and Dietetic Preparations ; with the Accentuation and Etymo- 
 logy of the Terms, and the French and other Synonyms. By ROBLEY 
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 and standard authority. 
 
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xvi MESSRS CHURCHILL'S SCIENTIFIC WORKS 
 
 THE following CATALOGUES issued by Messrs CHURCHILL 
 will be forwarded post free on application: 
 
 1. Messrs Churchill's General List of nearly 600 works on 
 
 Medicine, Surgery, Midwifery, Materia Medica, Hygiene, 
 Anatomy, Physiology, Chemistry, &c., &c., with a complete 
 Index to their Titles for easy reference. N.B. This List 
 includes Nos. 2 and 3. 
 
 2. Selection from Messrs CJiurchitfs General List, comprising 
 
 all recent works pitblished by them on the A rt and Science 
 of Medicine. 
 
 3. A Selected and Descriptive List of Messrs Churchill's works 
 
 on Chemistry, Materia Medica, Pharmacy, Botany, Photo- 
 graphy, Zoology, The Microscope, and other branches of 
 Science. 
 
 4. The Medical Intelligencer, an Annual List of New Works 
 
 and New Editions published by Messrs J. & A. Churchill, 
 together with Particulars of the Periodicals issued from 
 their House. 
 
 [Sent at the commencement of each year to every Medical Practitioner in 
 the United Kingdom whose name and address can be ascertained. A 
 large number are also forwarded to the United States of America, 
 Continental Europe, India, and the Colonies.] 
 
 MESSRS CHURCHILL have a special arrangement with MESSRS 
 LINDSAY & BLAKISTON, OF PHILADELPHIA, in accordance with 
 which that Firm acts as their Agents for the United States of America, 
 either keeping in Stock most of Messrs CHURCHILL'S Books, or reprinting 
 them on Terms advantageous to Authors. Many of the Works in this 
 Catalogue may therefore be easily obtained in America. 
 
DATE DUE SLIP 
 
 UNIVERSITY OF CALIFORNIA MEDICAL SCHOOL LIBRARY 
 
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