1 teacupful of spirits of turpentine.
About 4 level teaspoonfuls of white lead.
About 1 teaspoonful of lightning dryer.
Mix this well, paint the inside of the mould with it, two coats, which makes the gelatine waterproof.
To make a cast, oil the inside of the mould with lard oil, put the plaster jacket around it, so that it fits perfectly, and tie the two pieces of the jacket firmly together to prevent a disaster when the plaster begins to heat in the mould.
Mix your plaster with ice-water for the same reason, and you will have no trouble. For irregular objects, the working of a gelatine mould is perfection itself. It yields gracefully in coming out of the undercuts and around corners, takes every detail perfectly, and in the jacket its shape is always the same. A careful operator can make from twenty to fifty copies of a cast in a single mould before its loss of sharpness necessitates its abandonment.
[CHAPTER XXXV.]
CASTS OF MAMMALS, FISHES, AND REPTILES.
Casting Parts of Mammals in the Flesh.—Although it is usually impossible to carry more than ten or fifteen pounds of plaster into the field when you go off on a collecting trip, a quantity sufficient for a special purpose is often worth its weight in silver dollars. But many a fine subject comes entire to the laboratory, where the taxidermist can work his will upon it. If I have never done any other good thing in my life, I believe I have at least taught some of our best American taxidermists the usefulness and value of plaster casts taken from the flesh. It is only a few hours' work to make a mould and cast of the entire side of an animal as large as a large dog, or even a lion, and still less to take half the head, or the nose, a fore leg, or hind leg. Once we had an opportunity to cast the entire head of an immense bull moose, and right greedily did we seize it. The resultant cast has been of priceless value to us as an exact record of the form of a wonderful head. If you wish to do a fine piece of work, and have the animal in the flesh, by all means make a cast of one whole side of it. It will repay its cost ten times over. No record of form is equal to a cast, even though it be a poor one. I once made a mould of one entire side of the head of a large leopard in twenty minutes. It is about an hour's work to make a good mould of the entire head of a monkey, or two legs of a tiger.
The principles of this work have already been stated, and there is little more to be said. If the specimen is a large one, lay it upon the floor, build up around it with sand, or even wet sawdust, and arrange to take one side of the animal's head, or entire form, as the case may be. To take the two legs it will be necessary to first fill plaster under each one to make a separate piece. In order to keep the plaster from sticking to the hair, fill the hair full of thick clay-water, or thin clay, and plaster it down with the pasty mass so that the plaster Paris will not run into it. Coat the whiskers and eyelids with warm wax, or fill them full of clay. Do this thoroughly, to save the hair and save trouble. A little hair will stick in the mould anyway, but when you take the mould off, work the animal slowly and carefully from the mould, perhaps pouring in a little water to facilitate matters.
Always make a waste mould in these cases, to save time. If your cast breaks in two while you are chiseling the mould off, go ahead more carefully, and when you are done, chip the broken edges at the back, wet them with water, and stick them together with plaster. Small casts can be stuck together with shellac. If your mould breaks in pieces while you are taking it off, don't be discouraged, but simply put the pieces together, back them up with more plaster, and come up smiling for the next round.