If, then, we would wish to judge _a priori_ of the relative value of the processes of embalming, followed by the people of Asia and Africa, and of those employed by European nations, we ought to start from this double fact--that among the first, bodies abandoned to themselves have a tendency to dry and mummify, both on account of the small quantity of fluid they contain, and on account of atmospheric influences; whilst those of the second, rot and dissolve under the influence of contrary causes. We think then, with M. Rouyer, member of the Egyptian commission, that the most efficacious cause of the perfection of the art of embalming of the Egyptians, and of the wonderful preservation of the mummies, was the climate of Egypt, and chiefly that elevated and equal temperature (20° R.) which exists in the interior of sepulchral chambers, and in all subterranean places specially consecrated to sepulchres. A fact which ought to be joined to this last, has been proved by MM. Docts. Boucherie, Bermont, and Gaubert, during a visit to the caves of St. Michel at Bordeaux. These caverns which contain seventy bodies, taken from the neighbouring sepulchres forty years ago, and mummified by causes of which we shall speak in the sequel, are of a temperature of eighteen degrees. In order to terminate this discussion by a fact universally known, the mummies preserved untouched for several thousand years in the caverns of Egypt, become altered and destroyed very rapidly, when transported into Europe, and divested of their bandages, they are exposed to the influence of our atmosphere.[C] [C] The above observations on the natural mummies of caverns, &c., apply equally to the numerous specimens of Indian mummies found in Peru, Brazil, the Western States of North America, &c.--_Tr._ These various observations convince me that a precise knowledge of the art of embalming among the ancients, would not suffice to preserve bodies in our country; and what we do know, decides me to push my researches in another direction.[D]