In order to preserve a body for a month or six weeks, it is not even necessary to inject the blood-vessels--_a glyster of one quart, and the same quantity injected into the œsophagus, suffices for this limited preservation_. This process is adopted at Clamart for all the dead bodies destined for dissection. The preservative power of this salt will be easily understood, if its analysis be compared with that of the double sulphate given above. One hundred parts of _simple sulphate of alumine_, are composed of _alumine_ 30, of _sulphuric acid_ 70. This salt properly prepared, exempt from iron, commonly contains from thirty-six to forty for 100 of water. The following is a table of the different densities of this salt, according to the quantity of water in which it is dissolved. A killogram dissolved in five hundred scruples of water gives a quart of liquid which marks 32° on the areometer of Baumè. This same quantity in a quart of water Marks, 20° In two quarts, 17° In four quarts, 8° In five quarts, 6° This table is important, as it gives the composition of the different liquids of which we shall see the application. The liquid of injection, of which we have indicated the preparation and the quantity, is sufficient during winter, and moderate temperatures; but when it passes 20° it ought to be more abundant, or the solution more concentrated. When it is intended to preserve the body for a longer period, it is necessary to neutralize the sulphuric acid, which is taken up by the addition of acetate of lead. Two hundred and fifty scruples of this salt for one killogram of the dry sulphate produces the desired effect. If the preservation is to be indefinitely prolonged, the use of the acetate of lead will have a tendency at length to blacken the epidermis. Indeed, as it is impossible to cause all the lead to disappear, the small quantity of this salt remaining in the liquid will be then decomposed by the hydro-sulphuric acid disengaged by the corpse, or rather by the sulphur which it contains, and the salt of lead is changed into sulphuret, a black insoluble powder, giving to the body all the exterior aspect of the negro. I preserved in my cabinet an infant treated after this method; its skin, after the lapse of a year, became black, not of that colour assumed by animal matters in drying, but of the finest negro colour that could be conceived. I finish with these details; for the facts of prolonged preservation of which we have just spoken are derived from the wants of the anatomists; and, previous to proceeding to other considerations, it is best to exhaust all that we have to make known concerning my processes of preservation applied in amphitheatres to subjects intended to be dissected. The preservation of these subjects, it is known, would be prolonged without any advantage beyond two or three months at all seasons.