_The right arm and forearm_, the only parts remaining untouched, after the experiments of MM. the commissioners, were _amputated by myself_. I preserve this piece, as well as the hairy scalp; I can show them to anatomists to be compared with all the preparations obtained by other processes; none of them, I am convinced will be pronounced comparable to mine. The hairs remain so firmly attached to the scalp, that a strong pull will not detach them; I am quite sure that the injection has penetrated even to the capillary tubes of these organs; my experiments upon cats, dogs, and birds, have demonstrated the penetration of my liquid into the horny organs, hairs, or feathers, which clothe the skin of these animals. These facts will demonstrate all the services which it is capable of rendering naturalists. Finally, no process of tanning could give to the internal surface of the skin an aspect more satisfactory than that which offer other preparations deposited in my cabinet. 2. _Preservation in liquids._--The different preservative liquids produce effects very different from the process of desiccation; however, all those employed up to the present day, possess serious inconveniences, as any one may be convinced by reading the very commendable passages which we have extracted from the pamphlet of M. Dumèril. We shall point out some others which he has omitted. (_a._) _Nitric Acid_, the only one of all the acids, that can be of any use to the anatomists, preserves well, it is true, the preparation of the nerves, hardening their structure, and increasing their nacreous white colour; but it deteriorates all the other structures, it dissolves the gelatine, softens the muscles, and deprives the bones of their calcareous salts; it cannot be other than deleterious to objects of pathological anatomy, and natural history. (_b._) _Alcohol_, is more serviceable than any other liquor in use, but its high price renders its employment almost impossible for objects of normal anatomy; it hardens and sensibly alters objects of pathological anatomy; and these alterations, however trifling they may be, and unimportant to regular anatomy, are serious for the physician, who cannot have too exact an idea of the progress of disorganization in the living tissues. If alcohol is eminently useful for natural history, its costliness renders it impossible to extend the use of it as far as the interest of science demands. (_c._) _Diluted Alcohol_, to which is added the deuto-chloride of mercury, is a less expensive liquor; it preserves accurately enough the labours of the naturalist and anatomist, but it is not sufficiently faithful for a pathological anatomy. The same may be said of the hydro-chlorate of soda, the hydro-chlorate of ammonia, the muriate and nitrate of alumine added to alcohol.