“4. For the drying process Dr. Brunetti places the pieces in a vase with a double bottom filled with boiling water, and he fills the places of the preceding liquids with warm, dry air. By the aid of a reservoir, in which air is compressed to about two atmospheres, and which communicates by a stop-cock and a system of tubes, first to a vase containing chloride of calcium, then with another heated, then with the vessels and excretory ducts of the anatomical piece in course of preparation, he establishes a gaseous current which expels in a very little time all the fluids. The operation is now finished. “The piece remains supple, light, preserves its size, its normal relations, its solid elements, for there are no longer any fluids in it. It may be handled without fear, and will last indefinitely.” For the preservation and hardening of tissues for microscopic examination—as sections of tumors, glands, membranes, spinal cord or brain, etc.—Müller’s fluid may be employed, which is prepared as follows: bichromate of potassa, 75 grains; sulphate of soda, 35 grains; dissolved in six ounces of water. The specimen should be suspended in this fluid until sufficiently hardened to permit of a satisfactory examination. Preparation of Bones. Pathological specimens of bones, may be prepared either by boiling or maceration. The method by boiling should be employed, however, only where the texture of the specimen is firm and solid, as in cases of united fracture, etc.; and in these cases, care will be required to avoid injuring the specimen by too long exposure to the process. Maceration, however, is the better method for all cases, and the only one to be employed in cases where the bone is softened by caries or necroses. The specimen having been roughly stripped of the soft tissues, is to be thrown into a vessel of water, the latter being changed every day, as long as it becomes colored by the blood. It is now to be left until the putrefactive process has so softened the tissues that they may be easily removed, when, after being thoroughly washed in soda water, it may be dried and mounted. If the weather be cold, it will be absolutely important that the macerating be conducted in a warm room, else the process will be so slow as to convert the tissues into a form of adipocere, quite arresting the putrefactive process, and greatly damaging the specimen in its beauty and value. In this connection, it may be observed that bones from a subject that has been injected with chloride of zinc, can never be successfully macerated, the zinc having a sort of tanning effect upon the tissues, which enables them to resist the putrefactive process. Boiling is the only method by which such specimens can be cleansed.