Best French gelatine 1 part,Glycerine 6 parts,Water 6 parts,
Best French gelatine 1 part,Glycerine 6 parts,Water 6 parts,
Soak the gelatine in the water until swollen,then heat and add the glycerine,add a few drops of a saturated solution of carbolic acid, andfilter hot through white blotting-paper;
Soak the gelatine in the water until swollen,then heat and add the glycerine,add a few drops of a saturated solution of carbolic acid, andfilter hot through white blotting-paper;
6. A thick white varnish made by mixing oxide of zinc with copal varnish in a mortar.
The eyeball is placed, immediately after excision, unopened, in Mueller's Fluid for about three weeks, light being carefully excluded. It is then frozen solid by immersion for a few minutes in a mixture of finely powdered ice and salt, and immediately divided into lateral halves by means of a sharp-edged table-knife. The portion to be mounted is then placed in chloral solution for some weeks, in order to remove the yellow colour; light being still excluded, and the fluid being changed until it is no longer discoloured by the bichromate. The specimen next lies for twenty-four hours or longer in the weaker glycerine solution, and is then transferred for a similar period to the stronger glycerine solution, after which it may be mounted in the jelly without danger of shrinking. A specimen-jar being two-thirds filled with melted jelly, the half-eye is placed in it, the concavity upwards. When every interstice is filled, it is turned over (care being taken to avoid the inclusion of an air-bubble), and held in a central position in contact with the bottom of the jar. When cold and firmly coagulated, the jelly is coated over with white varnish. A few days later, when the surface of the varnish is firm, this again is thinly coated with a film of jelly, and thereby preserved from the ultimate danger of cracking. The jar is fixed with glue into a suitable wooden stand. The gelatine which yields the strongest and most colourless jelly is that manufactured by Coignet and Co., of Paris, obtainable in packets, and known as the "gold-label" variety. The specimen-jars, admirable both as to material and workmanship, have been made expressly for me by Messrs. F. and C. Osler, of Broad Street, Birmingham, from whom they may be obtained in any number. — PRIESTLEY SMITH, Birmingham.
Glycerine retards fermentation and decomposition to a remarkable degree. It combines readily with alcohol or water.
Boracic acid in small quantities mixed with a solution of saltpetre,i.e., 1 to 50, is stated to be of service in the preservation of flesh.
Previously salted meat cannot be preserved this way; salting evidently removes the phosphates. Action of boracic acid would, no doubt, set up acid phosphates, which are the prime causes of the preservation.
A preparation of borax has been brought out by Mr. Robottom, of Birmingham, who claims for it that it preserves all animal and vegetable tissue, as well as being useful for tanning skins. I shall refer to this preparation further on. Carbolic acid (pure) will be found a valuable ally of the taxidermist. Calvert was the chief if not the only maker of the pure preparation, which is sold in 0.5 lb. or 1 lb. bottles in a solid crystalline state, as if it were frozen. The bottle, with the stopper temporarily removed, must be plunged in boiling water to melt out as much as is required, to which must be added many times its weight or quantity of water. This diluted preparation will be found of infinite service in the hot summer months for pouring in the "gentle" infested throats or wounds of mammals and birds preparatory to skinning. Diluted and poured on a little burnt alum or pure tannin, and the mixture well shaken together, it forms an exceedingly strong preparation, as well as a valuable one, for painting the noses or pickling the tongues of animals before or after skinning. Two strengths of this will be found very useful. Thus:
No. 15 —Carbolic Wash, No. 1 (for Mammals).
Glacial carbolic acid, 2 oz.
Burnt alum or pure tannin, 1 oz.
Water, 1 pint.
Keep in stoppered bottle labelled "Poison," and shake up before using.
No. 16. —Carbolic Wash, No. 2 (for Birds).
Glacial carbolic acid, 1 oz.
Water, 1 pint.
Keep in stoppered bottle labelled "Poison," and shake before using. Carbolic acid is a caustic poison, and therefore must be handled carefully.
It sometimes happens that the taxidermist, if in a large way of business, is called upon to destroy the insects infesting, it may be, the entire collection of heads or skins hanging in some gentleman's hall. No better or more effective way of doing this is to be found than plunging them entirely in a bath composed of:
No. 17. —Carbolic Acid Wash, No. 3 ("Poison").
Carbolic acid, 1 lb.
Sal ammoniac, 0.5 oz.
Corrosive sublimate, 3 oz.
Pure tannin, 4 oz.
Hot water, 4 galls.
Mix this up in some out-house, or in the open air away from the house, if a fine day; and when the mixture is cold plunge the heads or skins in, holding the former by the horns, and stirring the latter about with a stick; in fact, allowing the mixture to touch the hands as little as possible.
It is, I believe, more efficacious if laid on hot than cold, but the danger to health is greater. I venture to say that if there is anything which will preserve objects for an indefinite period it is corrosive sublimate. Deadly though it be, and dangerous to work with, it has the advantage of being used as a finishing preparation, and therefore need not, except in extreme cases, be handled.
Instead of rectified spirits of wine, I have used with much success as an exterior wash for valuable bird skins, the following:
No. 18. —Preservative Wash.
Pure sulphuric ether, 1 pint.
Corrosive sublimate, 6 grs.
Keep in a stoppered bottle, labelled "Poison," and when used apply with a brush. This is more rapid in its evaporation than spirits of wine, but is very expensive. Of course, the more rapidly any spirit evaporates, and deposits poison previously held in solution, the better chance you have of not spoiling your specimens.
PRESERVATIVE FLUIDS FOR FISHES AND REPTILES.
I have lately given a great deal of attention to the preservation of fishes — and especially large ones — in some fluid which should have four advantages:
1. Perfect preservation of the specimen — and which also, if a foreign one, is consequently a long time in transit.
2. Its freedom from causing great shrinking or shrivelling of the integument.
3. The points 1 and 2 being so well balanced that the specimen is in a fit state--after many months — either to be treated as a specimen shown in fluid, or to be mounted by the process of taxidermy.
4. The comparative cheapness and facility of carriage of the preservative medium.
In trying to obtain all these advantages there seem almost insuperable difficulties in the reconcilement of these diverse conditions.
Dr. A. Guenther, F.R.S., the eminent, ichthyologist and Chief of the British Museum, recommends, in his new book, that pure or rectified spirits of wine (56 per cent. over-proof) be the only thing used for fishes, for permanent preservation in glass jars or tanks, and this even for ordinary fishes 3 ft. to 4 ft. in length, or even up to 6 ft. in length, if eel-like. "Proof" spirit (containing only 49 per cent. by weight of pure alcohol as against 84 per cent. contained in rectified spirit) is, says Dr. Guenther, the lowest strength which can be used.
These will then stand as
No. 19. —Rectified Spirits of Wine (56 per cent. over-proof),
and
No. 20. —Proof Spirits of Wine.
If a spirituous solution is absolutely required, I would substitute for pure spirits of wine methylated spirit (alcohol containing a certain percentage of impure gum or undrinkable wood spirit) as being cheap and sufficiently good for some purposes. It will not, however, bear any diluting with water; it must stand, therefore, as
No. 21. —Methylated Spirit (undiluted),
or as
No. 22. —Alcoholic Solution, No. 1.
Methylated spirit, 1.5 pints.
Burnt alum (pounded), 2 oz.
Distilled water, 0.5 pint.
Saltpetre, 4 oz.
This, which is to be well shaken together, becomes milky at first, but will soon fine down, and may then be decanted.
No. 23. —Alcoholic Solution, No. 2.
Methylated spirit, 3 parts.
Glycerine, 1 part.
Distilled water, 1 part.
Although turpentine will not preserve reptiles or fishes, yet, struck with the perfect manner with which I was enabled to preserve soft-bodied beetles for nearly a year in benzol or benzoline, I lately tried if this cheap and colourless liquid would be of service for other subjects, with the result that I have now some frogs (six or seven) in a glass jar containing benzoline which have been immersed for over three months, and have apparently undergone less change than if in spirits for the same length of time. Whether they are likely to be permanently preserved by this method I cannot, of course, yet determine, but if so, it would be a great gain, owing to the brilliancy of the liquid, its cheapness, and its advantages over all alcoholic spirit in its less powerful action on the sealing wax or coating used over the corks or stoppers of the glass preparation jars.
There is no doubt that pure spirits of wine will preserve objects for a great length of time, but the cost is very serious to most persons, or even to institutions of less importance than the British Museum — added to which the strong spirit unquestionably shrivels and distorts such objects as fishes and reptiles, whilst, diluted to any appreciable extent, spirit will not preserve anything for any great period. To obviate these inconveniences chemists have invented more or less perfect preservative fluids, the oldest perhaps of which is
No. 24. —Goadby's Solution, No. 1.
Bay salt, 4 oz.
Corrosive sublimate, 4 grs.
Alum, 2 oz.
Boiling water, 2 quarts.
Keep in stoppered bottle labelled "Poison."
[Footnote:"Bay salt" is salt formed by evaporation of sea-water in shallow lagoons or "salt-pans" exposed to the rays of the sun.]
No. 25. —Goadby's Solution, No. 2.
Bay salt, 0.5 lb.
Corrosive sublimate, 2 grs.
Arsenious acid, 20 grs.
Boiling rain water, 1 quart.
Keep in stoppered bottle labelled "Poison."
Note that, corrosive sublimate being a remarkably difficult thing to dissolve, even in pure spirits of wine, it may not be generally known that the addition of a saturated solution of sal ammoniac, in weight about half an ounce, is sufficient to dissolve many ounces of corrosive sublimate. Thus a solution useful for some purposes is easily made as follows:
No. 26. —Browne's Preservative Solution.
Saltpetre, 4 oz.
Corrosive sublimate, 0.25 oz.
Alum, 2 oz.
Sal ammoniac, 0.125 oz.
Boiling water, half gallon.
Keep in stoppered bottle labelled "Poison."
This, it will be seen, is a modification of Goadby's Solution.
In the three preceding formulae the corrosive sublimate must be dissolved in a small quantity of spirits of some kind, or, as explained above, by the addition of a strong solution of sal ammoniac.
No. 27. —Saline Solution for bottling Fish and Reptiles.
Bichloride of mercury (corrosive sublimate), 1 grain.
Chloride of sodium (common salt), 90 grains.
Distilled water, 1 pint.
Intimately mix, set aside, let settle, and when clear, decant and preserve in stoppered bottles. The following might also be tried:
No. 28. —Camphorated Fluid for Preserving Fishes, etc..
To distilled water, sixteen parts, add one part of rectified spirits of wine and a few drops of creosote, sufficient to saturate it; stir in a small quantity of best prepared chalk, and then filter. With this fluid mix an equal quantity of camphor water (water saturated with camphor), and before using, strain off through very fine muslin.
The bisulphite of lime (see formula No. 11,ante) would also, no doubt, be excellent as a preservative for fishes if not quite so much diluted. Chloride of zinc, much diluted, is recommended as a good preservative.
Dr. Priestley Smith's formula (see No. 14,ante) would do exceedingly well for small specimens to be subsequently arranged in glass-topped tanks, as at the British Museum.
Another formula, sometimes used in the medical schools for preserving parts of subjects, and useful as a pickle for fish and reptiles, is a preparation called Moeller's Solution:
No. 29 —Moeller's Solution.
Bichromate of potash, 2 oz.
Sulphate of soda, 1 oz.
Distilled water, 3 pints.
A saturated solution of chromic acid is also used for the same purposes. The chief disadvantage which both this and Moeller's Solution possess in common is their colour — a rich golden one — which, of course, stains everything with which they come in contact. This, however, is easily removable by the Hydrate of Chloral formula (see Priestley Smith's formula, No. 14, Section 2,ante).
This last (Moeller's Solution) I have kept purposely until the end, as it is the formula which, in my opinion, fulfils all the four requirements stated in the opening paragraph, as desirable in the preservation of the lower vertebrates. On my appointment to the curatorship of the Leicester Museum I had occasion to overhaul the "pickles" and prepare some fresh specimens, and was very loth to use expensive spirits, or even methylated, for large fish, and therefore tried many things with varying results. At last I was driven back on Moeller's Solution, and by its aid saved some specimens which were slowly rotting in other fluids, and successfully "pickled" such flabby things as sharks' eggs, sea anemones, and large-sized "lump fish." It was then tried on common "dog-fish," one of which came out limp, yet perfectly tough, and was skinned as an experiment after a month's immersion.
One day two large "topers" (a small species of shark), about six feet long, were sent from Scarboro'. My taxidermist being very busy at the time, I decided to give Moeller a severe test and pickle them. Accordingly — their viscera only being removed — they were tumbled into a large tub containing 2 lb. of bichromate of potassa to 20 galls. of spring water. This was on 13th Sept., 1882; I looked at them on 17th July, 1883, and they were perfectly fresh, quite limp,unshrivelled, and yet so tough as to be capable of any treatment, even to being cast as models, or "set up" by the taxidermic art; and this after the lapse of ten calendar months — a time more than sufficient for even a sailing vessel to come from any part of the world.
I changed the solution once, the total cost from first to last being one shilling and fourpence. Had pure spirit been used, the expense would have been many pounds, to say nothing of the great shrivelling which would have taken place by now. I must therefore think that Moeller's solution is, for the purpose, one of the best things ever invented.
PRESERVATIVE FLUIDS FOR MOLLUSCA.
Generally speaking, pure alcohol is the best for this purpose. Chloride of zinc would doubtless be of considerable service, and I notice that Woodward, in his "Manual of the Molluscs," says that chloride of calcium, made by dissolving chalk, or the purer carbonate — white marble, — in hydro-chloric acid until effervescence ceases and a saturated solution is obtained, is most useful as a preservative, as it "keeps the specimen previously steeped in it permanently moist without injuring its colour or texture; while its antiseptic properties will aid in the preservation of matters liable to decay."
Possibly some of the beautiful preparations in the Fisheries Exhibition of 1883 were prepared in this manner, and such objects as the sea-anemones, with tentacles expanded as in life, may have been instantaneously killed by osmic acid.
LUTING FOR STOPPERS.
No doubt, every one notices how the ordinary wax, which is used as a protective coating for bottles or "preparation" jars, is attacked by the contained spirit in such a manner as to be useless as a preventive of evaporation. Ordinary sealing wax, "bottle wax," beeswax, or paraffin wax, being useless, we are driven back on a very old recipe of the French naturalist M. Peron, who claimed for it advantages which it certainly possesses.
No. 30. — "Lithocolle" for Sealing Bottles.
Common resin.
Yellow beeswax (or paraffin wax).
Red ochre (in powder).
Oil of turpentine (turps).
The proportions of this luting are determined by putting more or less resin and red ochre, or turpentine and wax, as the "lithocolle" is to be more or less brittle or elastic. Melt the wax in the resin, then add the ochre in small quantities, and at each addition of this stir the whole briskly round. When the mixture has boiled seven or eight minutes, pour in the turpentine, stir it round, and set it near the fire to keep it warm some little time. To ascertain the quality, and if it requires more or less wax, put a little out on a cold plate, and note its degree of tenacity.
It is rather dangerous to prepare, and is best managed over a gas jet or stove, so arranged that the flame does not rise above the edge of the iron pot containing the composition; if this is attended to, not much danger can arise, especially if, in case of the composition firing, the lid of the pot be immediately clapped on.
Apply with an old brush, or by repeatedly plunging the neck of the bottle in the luting before the latter becomes cold. I have used an application of glue with great success on corks over spirits, by procuring the best glue, making it rather thin, and applying it whilst hot in successive coats. It will not do, however, for non-alcoholic solutions, nor for glass stoppers, from which it scales off when cold.
GENERAL REMARKS.
In all cases when "pickling" animals it must be remembered that the first pickle, whether alcoholic or not, is essentially deteriorated by the bloody mucus and water which exudes from the specimens, especially if large and "flabby;" this, of course, reduces the strength of the preservative medium. It is well, therefore, to have from three to four different vessels, in which the objects shall be successively immersed for several days, or even weeks, until, coming to the final preparation jar, they shall not stain the liquid in which they are ultimately to rest.
By using the various strengths of each preservative fluid one under the other, in which to steep the specimens, proper results will be obtained, by the exercise of a little forethought and judgment. Filtration through blotting paper or charcoal is necessary from time to time, and expensive spirits may be re-distilled when becoming too weak by constant use.
Large fishes must have small cuts made in the walls of the abdomen to allow the fluid to properly penetrate. In cases where the specimen is not required for dissection, the removal of the viscera facilitates the ultimate preservation.
If at 'any time it is necessary to throw away a quantity of inexpensive spent liquor which may smell offensively, a small quantity of the crystals of permanganate of potassa will instantly deodorise a large quantity of fluid, and this without adding to it any offensive scent of its own, as in the case of chloride of lime or carbolic acid. The vessel must be afterwards well rinsed out in clean water, as 'the potassa temporarily stains everything in contact a rich purplish red.
Some experiments which I conducted with benzoline incontestably proved to me its valuable properties. I experimented on a Cornish chough — an old specimen, infested with maggots or larvae of the "clothes" moth. I immediately plunged it in benzoline, took it out, drained the superfluous spirit off, and rapidly dried it by suspending it in a strong current of air.
It took but a short time to dry, and, though the feathers were very slightly clotted after the operation, yet, by a little manipulation, explained hereafter, they soon arrived at their pristine freshness, and all the insects which previously infested it were effectually killed. I afterwards found on another specimen — a short-eared owl — two or three larvae feeding on the feathers. I poured a little benzoline over them in situ, and they fell off, apparently dead. I kept them for a day, and by that time they were shrivelled and undeniably dead.
Here, then, we have the two elements of success — a perfect destroyer of insects, and an agent not damaging, but positively beneficial, to the feathers of birds when applied; added to which, is the remarkable cheapness of benzoline. Caution — do not use it near a candle, lamp, nor fire, as it gives off a highly inflammable vapour at a low temperature; it also fills a house with a peculiarly disagreeable odour, finding its way upstairs, as all volatile gases do; so it had better always be used in the workshop or outhouse.
I have just discovered — and feel very "small" that I did not do so before — that benzoline perfectly preserves birds "in the flesh" for a considerable time. I tried it on a razorbill (Alta torda, L.), which I placed in a "preparation" jar, filled with common benzoline at l s. per gallon. The bird was simply cut under the wing to allow the benzoline to penetrate, and was left for three weeks; at the end of which time it and taken out, cleaned in plaster (as described in Chapter XI.), and made a most excellent taxidermic object! The advantages of this to the overworked professional are obvious.
In very severe cases I have used turpentine ("turps") with excellent effect; in fact, as a destructive agent for insects, I prefer it to benzoline, having now mastered the hitherto fatal objections to its use on birds' skins. For the skins of mammals there is nothing to beat it. This will be enlarged on in the chapter on "Relaxing and Cleaning Skins."
In thus speaking of benzoline and turpentine as agents in the destruction of insect plagues, I mean, of course, that the specimens should be plunged into, or have poured over them either benzoline or turpentine. This seems to have been lost sight of by some former correspondents of mine, one of whom writes —
"In your toxicological section, I do not find any opinion on atmospheric poisoning of acari, etc..
"If not giving you too much trouble, I should be glad to know whether you think spirits of turpentine would be efficacious if allowed to evaporate in a case of birds in which moths have lately shown themselves.
"I am unwilling to have them taken out, in fact they have not been cased twelve months, and I thought of boring a hole in an obscure corner with bit and brace, and inserting a saturated sponge, and then closing it again.
"Waterton says — 'The atmosphere of spirit of turpentine will allow neither acarus nor any insect to live in it.' Do you believe this?"
My answer to him, and to all such correspondents, was that I had repeatedly proved that all such little vermin did not care a bit for the fumes of benzoline, nor of any spirits whatever, as I had caused gallons of turpentine, etc.., to be poured into large cases containing specimens without producing the smallest effect, unless it absolutely touched them, but that I had partly succeeded by introducing cyanide of potassium (deadly poison) into small cases containing birds, through a hole bored for the purpose; but it was objectionable —
(I) on the score of its danger to health, should the poisonous vapour escape; and
(2) because it deliquesced rapidly in any but the driest atmosphere, by its affinity for damp, and, consequently, often caused mildew in cases of birds, etc.., into which it had been introduced. The fumes of sulphur during combustion are, on the contrary, really of service in destroying insect life, as evidenced in the fumigation of hospital wards, etc.., but I cannot tell how anyone may burn sulphur in specimen cases without half choking himself, and probably setting on fire the fittings and spoiling the work altogether. It is also objectionable because it readily discharges certain colours from fabrics, flowers, and birds' feathers. My advice is, therefore, to pull to pieces any case infested with insects, to burn all fittings not absolutely valuable, and to drench with turpentine all specimens, together with all the rockwork and fittings desired to be retained.[Footnote:I would indeed advise the destruction by burning of the birds themselves even, should they be common specimens, or easily replaced.]
Crude creosote, in little pots or saucers, is a great deterrent to the visits of insect plagues; it cannot, however, be exposed openly, as its scent is overpowering and decidedly unhealthy for use in private houses. In museums it does very well if cased up.
With regard to camphor in museums, although it is so constantly used, I consider it of no use as a deterrent. A small piece of tallow candle is equally efficacious, and of late I have had much more faith in insect powders, the best of which is, I believe, compounded of the petals of the Russian tansy (Pyrethrum roseum). This has certainly some principle contained in it not obvious to our senses. It is perfectly harmless to man, and to domestic animals, but on insects its action is entirely different. I cannot as yet discover whether insects eat it, or if its smell overcomes them, whether it repels, or attracts them to their doom. A series of experiments has left me just as much in the dark as ever. Certain it is that I have never found insects among skins over which it has been strewn.
There is, however, one slight objection to its use, which is that it stains light-coloured skins, if at all greasy, with its fine, brownish-yellow dust. This is, however, but a trifle, easily avoided, in face of its unquestionable value. I have used it now for many years, and have never had cause to alter my opinion as to its efficacy. The best only must be procured, from some well-known wholesale house, price about 3s. per lb. That sold made up in small quantities is generally adulterated and useless. No curator should ever be without it, and a small quantity should always be placed inside a newly-made skin. It can also be worked up in many of the preservative pastes, or macerated in spirit as a wash, for theinsideof skins.
Baking or stowing maggot-infected specimens is recommended by some authors, but I strongly object to it in the case of old or valuable skins, firstly, because the heat can seldom be properly regulated, unless in an apparatus specially constructed; secondly, because heat sufficient to kill the larvae is also sufficient to crimp or twist some part of the plumage or render the skin, if an old specimen, too crisp or tender for ultimate handling; thirdly, because even a moderate degree of heat is sufficient to set free the fat contained in the skin, and thus spoil the feathers.
Perhaps the tyro may remark, "But in a preserved and stuffed skin there ought to be no fat to ooze out." Quite true, there ought not to be, but as skins are usually dressed with arsenical soap, the fat, instead of being dried up, is beautifully conserved, ready to run out at the slightest provocation, or be drawn out by the capillary attraction of the threads used in sewing up — another hard knock for arsenical pastes!
Writing about pastes reminds me that no taxidermist should be without a pot of flour paste, which is far better and more cleanly than gum or glue for sticking in loose feathers, etc.. For a small quantity, sufficient to fill a jam-pot, take
No. 31. —Flour Paste.
Good wheat flour, 2 oz.
Essence of cloves, 0.5 a teaspoonful.
Water, 0.5 pint.
Mix the flour with part of the water in a basin, being careful to crush out all the lumps, and work it up smoothly to the consistence of thick cream; add the remainder of the water, and boil for a few minutes in a saucepan. Turn out into a jam-pot, and when nearly cold stir in the essence of cloves; this latter gives an agreeable odour to the paste, is not poisonous, and preserves the paste indefinitely from turning mouldy. A few drops of carbolic acid may be used instead of the cloves; but in this case the pot must be labelled "Poison."
Strong gum water may be made from gum arabic, into which a little powdered white sugar is stirred. Essence of cloves prevents mould in this also, unless there be an excess of water.
A fine paste, useful for paper or photographic work, is made from rice-flour.
"Dextrine," in powder, is cheap and strong, easily soluble in cold water, but as a paste shows up on feathers, etc.., much more than wheat-flour paste.
Cement, for uniting broken bones or fossils, or to fix shells, etc.., on tablets, is, says the late Frank Buckland, made thus
No. 32. —White Cement.
Beeswax, 1 part.
Powdered plaster of Paris (best fine), 5 parts.
Resin, 4 parts.
Warm the edges (when possible) and use the cement warm.
I would advise the plaster being stirred into the other two ingredients as wanted. The great objection to this and to all the "coagulines" is that the edges of the specimen require warming, which cannot always be done.
Another good colourless cement is
No. 33. —White Cement, No. 2.
Gum tragacanth in powder, 1 part.
Gum arabic (acacia) in powder, 1 part.
Glacial acetic acid, a few drops.
When used, moisten the gums with a little of the acetic acid diluted.
Gum mastic dissolved in alcohol, and white shellac dissolved in naphtha, are two other white cements.
Where, however, colour does not matter, take
No. 34 —Brown Cement.
Common shellac, 0.25 lb.
Spirits of naphtha, 0.5 pint.
Place them in a bottle in a warm situation on a closed stove, or in a vessel containing hot water. Be careful of fire. The edges of bones or undersides of fossils are smeared with this, tied with string, and left for a day or so to unite.
The reader has now a repertoire of poisonous and harmless preparations from which he may choose. As for myself, for the preservation of birds, I pin my faith to formula No. 4, viz., my Preservative Soap for the inside of the skin, and a wash of benzoline or turpentine liberally applied from time to time — say twice a year — to the outside of all uncased or exposed specimens. This, it will be seen, entirely does away with the use of any poison, and yet is proved to be of the highest efficacy.
For those who do not object to expense nor to the use of a poisonous preparation, a wash of Waterton's Solution (No. 5), or the sulphuric ether preparation (No. 18), can be substituted for benzoline or turpentine. I mention the expense, because only rectified spirits of wine, or pure sulphuric ether, will do for birds; the methylated spirit, though of service for washing over most subjects, is not so good when applied to the delicate feathers of birds, as it leaves on drying a certain impure residuum behind it.
For mammals I recommend my formula of burnt alum and saltpetre (No. 9), followed by a wash of benzoline or turpentine twice a year, or by any one of the mercurial preparations given.
On a retrospect of this chapter it will, I think, be admitted that, if I am adverse to the use of any poisonous preparations in taxidermy, I at least point out the why and wherefore, as also an alternative course, showing at the same time the benefits and defects of both systems. I now, therefore, leave the amateur to choose for himself — bearing in mind the time-honoured aphorism,chacun à son goût.
images/Image155.gifPlate II Skeleton of Peregrine Falcon
SHOWING THE PROPER POSITION OF THE VARIOUS BOXES.
Explanation: follows:
SKELETON OF PEREGRINE FALCON (above.)
SHOWING THE PROPER POSITION OF THE VARIOUS BOXES.
Explanation:
A, skull; B, upper mandible; C, lower mandible;
D, cervical vertebrae (9);
E, humeri (sing. humerus); F, radius; G, Ulna;
H, carpus, or wrist I and J, metacarpal bones (8); i, "knuckle" joint;
K, pollex (first digit, or "'thumb"); K2 and K3 second or "index" digit, and next or third digit;
L, pelvis or "ossa innominata" ilium, ischium, and pubes anchylosed;
M, femur; N, tibia; O O, fibula;
P, metatarse, or "tarso-metarsus" (3, sometimes 4 bones);
p, actual "knee" joint; q, "heel," or tibiotarsal joint;
Q, hallux (first or "big" toe), called in ornithology the "hind" toe
R, fourth (or outermost) toe; S S sternum, or breast bone.
CHAPTER V.SKINNING AND PRESERVING BIRDS.
IN order that this shall be a thoroughly practical chapter, I will, in my method of working, copy the admirable plan of my old sporting favourite, Col. Hawker, who, when wishing to note down some difficult point, was in the habit of doing with his own hands all things pertaining to the matter at issue, because, as he said, he might not make mistakes when subsequently writing upon knotty subjects intended for his readers' consideration.
I have, therefore, specially procured a starling, as I consider this bird the very best for the amateur's purpose, not only on account of the toughness of the skin, but also because, being a medium-sized bird, it presents no difficult points in skinning, and with this bird before me I shall minutely instruct my pupil, pointing out each step that has to be taken and each difficulty that is likely to arise.
As I shall have occasion constantly to refer to the various parts of the skeleton, I now give an engraving of that of the Peregrine Falcon, in order to help my explanations in the future (see Plate II.).
Having placed ready for use the skinning knife (see Fig. 11), the scissors (Fig. 14), and the cobbler's crooked awl in handle, a pot of preservative mixture, some cotton wool or wadding, some tow, and a needle and thread; lay the starling on its back on a piece of clean paper, the head of the bird pointing from the operator; then seize the bird by the sides of the head with the first two fingers and thumb of the left hand in opposition, the awl held in the palm of the right hand, and a piece of wool between the right-hand finger and thumb; then insert the point of the awl between the upper and lower mandibles, and, having opened them, keep them open with the first finger of the right hand, removing the piece of wool which should have been previously placed there by the sportsman (see instructionsreshot birds, at end of Chapter II.). Replacing it with the fresh piece of wool held in readiness, plug the nostrils in the same manner.
As even this simple operation will have somewhat disarranged the feathers of the head and neck, smooth them down with the fingers, taking care, however, not to stretch the neck in doing so. The next operation is to hold the left-hand wing with the left hand, and with the fingers of the right hand break or disjoint the bone of the wing as close to the body as possible,i.e., across the "humerus" (E) (in the case of large birds, or for some special purpose, this bone is often left intact, but the amateur will be puzzled how to subsequently arrange it in the skin if unbroken). Repeat this on the other wing. For those whose fingers are not strong enough to do this effectually, I recommend a small pair of flat-nosed pliers, some sizes larger than the "feather pliers" (Fig. 19).
Large birds may have their wings broken at the humeri (E) by striking them with a stick or hammer in such a manner as not to break nor seriously disarrange the feathers; the largest-sized pliers (Fig. 16) may also be used for this purpose, but in that case a piece of clean rag should be folded in the jaws of the pliers so as to envelope the upper and under surface of the wing, in order to protect the feathers from injury. Practice will, however, point out the best method of doing this. Next take hold of the legs with the fingers and gently twist them out of joint at the junction of the tibia and femur.
Now, keeping the head of the bird toward you, part the feathers away from each side of the sternum or breast-bone; then with the knife held short in the hand, the point placed exactly in the centre of the bird (calculating from the bill to the tip of the tail), make the first incision just on the right side of the breast bone down to the vent, taking care not to cut so deeply as to expose the intestines. Now turn the bill towards your right, and gently lay hold of the cut edge of the skin, which you see shining whitely in front of you; then with the point of the knife — the cutting edge kept on the flesh — gently loosen the skin above, below, and downwards. Completely reverse the bird, and repeat this for the other side.
At this stage the body may be held down, with the knife pressed on the side of the breast bone, and thus the two first fingers of the left hand may be advantageously employed — but in a very gentle manner — to loosen the skin around the upper part of the breast-bone from the inside, while the thumb regulates the pull from the outside. All must be done with the feathers kept as much away from the flesh as possible.
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Fig. 22 — Starling — Showing Position of First Incision and the Commencement of the Removal of the Skin.
Fig. 22 shows the appearance which the specimen should now present.
The skin being, as it were, nicely "persuaded" from the flesh (more being done by pushing than by pulling), the legs begin to appear. Take hold of the one nearest to you with the right hand, at the same time inserting the fingers of the left inside the skin; then, by gently pushing up with the right hand, free the legs sufficiently to show the second joint, where it has been previously twisted or broken.
Laying down the knife, and picking up the scissors, force their point underneath the joint, marked P in Plate II., and cut it completely off; it should then be clear of the flesh, showing the skin on either side as if it were a stocking turned inside out. Pull it gently by the claw back into its proper position, and there leave it, and do the same by the other leg, turning the bird again for that purpose.
Both the legs should now be entirely free, not holding to the body at any point. Taking up the knife again, carefully work with it down toward the tail, and as far round the back as you can get with safety. Now let the bird rest on its head, as it were, with the beak from you, and, placing the fingers with the thumb on the back (which is now underneath), the middle finger on the root of the tail inside, flanked by the first and third fingers keeping down the skin on either side, cautiously insert the knife through the skin of the vent, and cut that free, cutting upward in a slanting direction; having done this, carefully cut away on the root of the tail, at the same time freeing it wherever it sticks; then, when nothing but one bone, that is to say, the last caudal vertebra, holds it, slip the knife underneath and cut with a drawing motion upward. The tail is now entirely separated from the body.
Now advance the fingers of the left hand and seize the bottom part of the loosened body with the right hand, and by pushing with the finger-nails, and occasionally using the knife where the tendons hold the skin, gradually work up the back, turning it round and round, and working very carefully until the place where the wings have been previously broken is arrived at. Again lay down the knife, and taking up the scissors, cut the wing nearest to you away from the skin; do the same with the other side; and now the only thing which holds skin and body together is the neck. Taking the whole of the body in the hand, proceed with the fingers of the other (using no knife) to gradually cause the skin to leave its attachment at the neck. With care work over the head by the same means, and here progress is stopped by the skin being held on either side of the face by a little membrane; this is the inner skin of the ears.
Regaining the knife, slip the point underneath, and gradually lift them out, cutting towards the flesh and not towards the skin. This done, the skin will appear darker, immediately above this point. These are the eyes; carefully cut on top of them with a very gentle motion, until they are skinned to where only a very thin membrane hides them from view; arrived at this, the knife-point must be pushed gently underneath, and an upward cut made, which, if carefully done, entirely severs the eyelids from the retaining membrane. The exact point shown in Fig. 23 is now reached.
images/Image157.gifFig. 23 — Skin of Bird Turned Ready for Severance from Body
After this sever the skull from the neck at the point where the dotted lines A — B are shown in the drawing. This exposes the brain without cutting off too much at the base of the cranium, the shape of which is wanted for subsequent operations. After the body is completely severed, proceed to pull the tongue out (unless wanted for show) by placing the knife on the other aside of it in opposition to the thumb, give a smart pull, keeping an even pressure on, and the tongue will come out with little or no difficulty.
Next enlarge the orifice at the back of the head by cutting a triangular piece out towards the palate or roof of the mouth, scooping the brains out with the point of the knife, having a small piece of paper in readiness to receive them. During this operation hold the beak of the bird through the skin of the neck by the two first fingers, and thumb, the latter being uppermost, the other fingers being employed in keeping the remainder of the skin with the feathers out of harm's way.
Inserting the point of the knife at the back of the eye, place the thumb on the eyeball and gently pull it out, taking care not to let the point of the knife cut upward so as to burst the eye, or the effect will be to liberate the dark-coloured pigment or the vitreous humour, and thus wet or stain the feathers. Having done all this, there will still remain some little flesh at the back of the eye and the junction of the mandibles, and this must be carefully cut away so as not to dis-articulate the latter. The Preservative Paste now comes into requisition, and with this the skull and orbits are well painted inside and out. A little tow, previously chopped by the medium of a sharp pair of scissors, is now pushed into the empty skull, with the "stuffing iron," which is a small piece of thick wire (see Fig. 21). For large birds the tow forceps (see Fig. 20) may be conveniently used.
Having neatly filled the head with the tow, proceed to put a small piece of cotton wadding in each orbit. (Note, be careful that tow only is pushed into the head, as if never so small a piece of wadding gets into the cavity of the head it will effectually prevent any subsequent mounting of the specimen, as, singular though it may appear, a small piece of wadding is more than a match for a pointed wire.)
During all this time the neck must be kept as short and as little stretched as possible. In some birds a line of fat will be observed extending from the neck to the back or even to the breast, which must be as carefully as possible scraped off the skin by using the edge of the knife, guided by the thumb. Having done this, paint the neck only with the preservative, and lay the skin on the paper, back upward and tail from you; the under part of the head in this position points upward.
Place the thumbs of both hands, their nails touching each other, at the back of the head with the first two fingers of each hand placed in this wise: forefingers along the side of the face, second fingers underneath on the top of the skin of the head; then, by gently pushing with the thumbs and pulling or scratching, as it were, with the other fingers, gradually force the head through until the mandibles appear, as also the eyelids. Let go with the right hand, still keeping the thumb of the left pressing against the head; and, by gently working with the two first fingers of the left hand outside the feathers, and by pulling the beak upward and toward you with the right, the bird is returned to the position shown in Fig. 22.
As the bird now lies, it is optional whether the flesh is cleaned away from the root of the tail first or from the legs and wings. I will, however, in this case take the wing on my right. Place the right hand underneath, lift the wing as far up into the skin as possible, and by holding it tightly in that position with the finger and thumb of the left hand, a ridge of skin becomes visible, running down each side, and framing in, as it were, a little oval-shaped piece of flesh, i.e., that lying between the "radius" and "ulna" The broken bone and flesh of the wing is now toward you. Clean the flesh away from this and then devote the attention to the before-named oval-shaped piece of flesh. Putting the point of the knife down on the right, lift and scoop away (using the greatest care meanwhile) some small pieces of flesh. This by degrees reveals the top of another little bone, from under which all the flesh to be seen must be scraped away; anoint this freely with the preservative, and return it to its normal position after tying a small piece of strong thread through the loop of the bone (in large birds a little tow should be placed in the cavity).
If this process is too tedious, or not quite comprehended by the amateur — i.e. the clearing out of the flesh between the radius and ulna — the smaller bone of the two — the radius (F, Plate II) may be twisted or cut out entirely, leaving only the larger bone of the two to clear of flesh. Sometimes — but this with large birds only — the wing may be advantageously cut from the outside along its entire length underneath, the flesh removed, skin dressed, and the cut carefully sewn up.
Do the same by the other wing, and then push the leg on the same side up through the skin, pushing the skin down with the fingers and thumb of the left hand, and pulling with the right, until you have stripped the skin nearly down to the so-called "knee,"q(not the proper knee, however, that being situated higher up — Plate II), or tibio-tarsal joint. At this joint a bundle of little "leaders," or muscles, assemble; cut them away from around the bone (without interfering with the joint, however), and they will roll up with the flesh to the head of the bone previously cut off at the proper knee joint, and can there be easily pulled off. (In practice, it will be found that retaining the full length of this bone — the tibia — is not desirable for subsequent operations; it may therefore be advantageously shortened by one-half.)
Anoint with the preservative and neatly wrap a piece of tow around the leg-bone (or tibia) to the supposed shape of the flesh previously removed. Return the leg to its natural position; and repeat the same on the other side.
The tail is now the only thing left which requires to be freed from flesh. Keeping the beak still from you, push the tail, with the left hand, as far up into the body as possible, then clear it of every particle of flesh by scraping and cutting, taking care to cut away the oil ducts or glands — usually full of a thick fat — and being careful also not to cut away the attachment of the roots of the feathers to the skin; anoint with the preservative, and return. Several little streaks of fat in various parts of the skin may now be seen, which must be carefully scraped away.
The wing bones must now be tied nearly together by the pieces of thread previously attached; the distance between them varies with the size of the bird's body previously removed (this knowledge is, of course, gained by experience, but amateurs are recommended to take careful measurements of this and other analogous points). The whole of the skin of the back, body, and throat is to be well anointed. Now take the forceps (see Fig. 20), and form a little neck of tow on it, introduce it into the skin, leaving the end of the tow resting against the back of the head. Then insert some larger pieces of tow with the fingers or tongs into the body, and when you have shaped it as nearly as possible to the original body of the bird — taking care to nicely observe the adjustment of the several parts — neatly sew up the skin with a fine needle and thread by an under stitch on the edges of the skin, drawing it tight after two or three stitches; and thus proceed until the bottom is reached, avoiding the common fault of sewing the feathers in with the stitches.
Some few ends of tow will possibly be protruding from the lower part, which must be cut off before the final stitch. The bird's legs are tied one across the other, and the wings pressed close to the body in the proper position; the neck is also shortened, and a little narrow band of paper is cut, and placed underneath the bird, brought round the butts of the wings or shoulders, and pinned together on the top of the breast; a needle and thread are inserted through the nostrils, the thread is brought round underneath the bird's lower mandible, and is tied in a knot to keep the beak closed.
In the course of a week or so, when sufficiently dry, the bandage is removed, and thus we have what is technically called a "skin."
This is the loose body method of making skins; perhaps a better plan is making a body — see farther on — on wire, which should not come through the top of the head, or on a piece of stick (a lucifer match with the top broken off will do for small skins) coming into the base of the skull; this gives a great support to the neck, and prevents the common fault of the skin breaking away just above the shoulders.
If great nicety is desired — and neatness in making a skin is everything — remember particularly not to overstuff it; it will really require just about half as much packing as you would at first imagine sufficient to fill it. Be careful as to the set of the wings, at the shoulders especially; and after having coaxed every feather with loving care into its proper position, wrap the whole skin in a sheet of wadding, leaving the ends open, and put away in a secure place to dry.
Another method of shaping skins whilst drying is described by Mr. Batty, the well-known American taxidermist, who makes a drying board for small skins in the following manner (see Fig. 24): Procure a piece of board of the length and width you require, on which nail on edge 0.75-inch slips of wood two inches high at intervals required; between these supports stretch stout cardboard in the form of "gutters." In these, padded in wadding, the skins rest until dry.
images/Image158.gifFig. 24 — "Set" or Drying Board for Birds' Skins.
Often blood and other substances clog and spoil the feathers of a bird; how to remove these will be found explained in the chapter on Cleaning Birds' Skins.
images/Image159.gifFig. 25 — Starling Properly Made Into a Skin With Label Attached.
In noting the sex of a bird an important matter, only managed in most cases by the aid of a little dissection — it will be necessary to cut the body, after it is out of the skin, through the ribs along the side close to the back, open it, and look upon the kidneys (dark coloured masses apparently let into the hollow of the back-bone at the narrowest part of the body) for the sexual organs.
If a male, there will appear just upon the upper end of the kidneys, one on each side of the back bone, two little oval-shaped bodies, usually of a dull white or light yellow tint (do not mistake the supra-renal capsules — quite yellow, small, and a little higher up — for these).
If a female, these two small oval bodies will be replaced a little lower clown by a string or bundle of eggs, very minute in some seasons, but strongly marked and large in the breeding season. It is sometimes difficult to tell the sex — in young birds especially; but a good plan is to get a bird, known by its plumage to be a male - say a cock sparrow — and a female bird, and dissect out these organs, putting them in spirits in separate bottles, the organs of each sex attached to its part of the bone and kidneys, and keep them for reference until experience teaches the way to readily decide sexes.
A label is attached to the legs, giving scientific and common name of bird, sex, locality, and date, and name or initials of collector. Thus: