Plaster moulds and casts, it must be remembered, are, when dried, about a quarter of their weight when wet, and the same bulk of dried (not dry) plaster is not half the weight of dried clay.
A very scientific way of getting the correct shape of a fish for mounting by taxidermy is to take a cast of the specimen and to then adjust the skin, stuffed by the dry-plaster process, into the cavity of the mould, suffering all to dry therein.
Fishes are now and then mounted in halves, should one side be very badly mangled; the effect is not very good, however, and should not be resorted to but in extreme cases.
Large fishes, such as sharks, rays, and sturgeons of great size and weight, must be cast by the "piece-mould" process — described in Chapter XII. The mounting of such as these, by processes of taxidermy, differs from all previously described in this chapter. When of excessive size and weight, they may be "set up" with wood and iron (see Chapter VII.), or if smaller — say, up to 5 cwt. — may be managed by being cut underneath along the stomach, from head to tail, and mounted by two short iron rods being screwed into a beam of wood, or bar of iron fitted into the body, now filled out with hay, straw, or, better still, clean shavings, supplemented by tow here and there.
When all is sewn up, and the mouth — if open — modelled by any of the methods described in Chapter XII., the short iron rods protruding from each end of the fish must be let into metal sockets (iron gas pipes will often do) screwed into iron feet, supporting all clear from the floor of the museum or room they are to be exhibited in.
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[CHAPTER IX.
SKINNING, PRESERVING, AND MOUNTING REPTILES.]
THE chief requirement in preserving reptiles is a fine and delicate hand, in order to deal successfully with these mostly thin-skinned objects. I will now take one of the easiest reptiles as our first study, viz., the common snake.
Formerly, by the old method of skinning, the bodies of all snakes were removed through an incision made along the skin of the stomach. This was a mistake, for the smaller snakes may be skinned through the mouth, in this wise: Open the jaws of the snake to their fullest extent, taking care, if a venomous one, not to scratch the fingers with the fangs, which, in the adder or viper, lie folded backward along the roof of the mouth. If the fangs are not required to be shown, the safest plan will be to cut them away with a pointed pair of scissors.
Holding the snake by the back of the neck with the left hand, push the pointed knife or scissors into the mouth towards the back of the head, feeling at the same time with the point of the knife for the first joint of the cervical vertebrae, having found which proceed to dislocate it with the point of the knife, gently feeling your way, and cutting downward toward the right hand, the thumb of which presses against the snake's head at the under jaw. Feel round with the point of the knife or scissors up toward the outer skin, gradually working the flesh away. Cut away the under jaw, inside the skin, from its attachment to the flesh, pushing the point of your scissors or knife at the same time as far as you can get it down inside the skin.