℞. Of suet, 5 parts. Burgundy pitch, 2 " Oil of olives, or of nuts, 2 " Of fluid turpentine and colouring matter, dissolved in volatile oil, 1 "
This latter part should not be mixed until the liquor is well melted and ready to be put into the syringe, as the heat will volatilize the volatile oils, which will become disengaged in the form of gas, and cause the mass to occupy a very great volume.
As a matter of injection, the dissolved gum elastic or caoutchouc may be employed; it becomes gelatinized in losing a portion of its menstruum by desiccation. After leaving this matter in a moist place, and having well washed it, in order to clean it of the clayey matter which generally impregnates it, it may be dissolved in volatile oils by heating it in a sand bath, with a moderate fire in a matrass with a long neck; adding by degrees, a sufficient quantity of oil to render the mass very fluid, incorporating with it the colouring matters which have been previously ground in an essential oil. The gum elastic may also be dissolved in ether, but this process is too expensive; and as a matter for injecting this liquor is not preferable to the other. The elastic injections are only advantageous in the preparation of parts which are not to be exposed to cutting instruments, and to which it is desirable to preserve a certain degree of suppleness, as in the injection of the cotyledons, or the placenta of women. This liquor, it must be confessed, has the great inconvenience of retaining its odour a long time, assuming its solid form with difficulty, and of rendering the preparations pitchy, and rebellious to varnish, and becoming loaded with dust.
There are certain organs which may be injected with solid matters, in order to obtain, in relief, resisting, but coarse, the forms of interior cavities. Such is the injection with the matter which forms the stucco paste, or of fine plaster diluted with gelatinous water, which gives to this salt a greater solidity when it takes its consistency. This gross matter is employed with advantage to render more solid the membranes of certain cavities, in the thickness of which it is desired to search for the nerves. Pure wax does not present the same advantage, because it exacts more heat, and contracts more by cooling, although it is more applicable in case it is proposed to corrode with acids all the fleshy or osseous parts, in order to become acquainted with the real form of their interior capacity: in fine, the fusible metallic mixture of Darcet is employed under different circumstances, but it is not more useful.[11]
