Practical Taxidermy Part 10

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.

a.r.s.enious 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 quant.i.ty 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.

b.i.+.c.hloride 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 quant.i.ty of best prepared chalk, and then filter. With this fluid mix an equal quant.i.ty 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 gla.s.s-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.

b.i.+.c.hromate 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 curators.h.i.+p 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 b.i.+.c.hromate of pota.s.sa 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 s.h.i.+lling 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 quant.i.ties, 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.