COMPOSITION OF MUSCLES. 375 



a proof that it is impossible to find out essential differences by means 

 of ultimate analysis :" and he adds " Nothing has ever surprised me 

 more than the assertions now so frequently repeated, that muscle and 

 blood are identical in composition two substances which present, in 

 fact, no other point of resemblance, except this, that they both con- 

 tain protein compounds. But if we proceeded upon this principle, we 

 should be induced at present to apply the term identity to a great num- 

 ber of substances indeed." 



Muscular structure is liable, under particular circumstances, to a 

 singular kind of conversion, to which it may be well to advert. When, 

 about the latter part of the last century, it was determined, for pur- 

 poses of salubrity, to remove the bodies from the churchyard of Les 

 Innocens at Paris 1 which had been the cemetery for a considerable 

 part of the population of Paris for centuries ; the whole area, occupy- 

 ing about seven thousand square yards, was found converted into a 

 mass, consisting chiefly of animal manner, and raising the soil several 

 feet above the natural level. On opening the ground, to remove the 

 prodigious collection of dead bodies, they proved to be strangely al- 

 tered in their nature and appearance. What had constituted the soft 

 parts of the body was converted into an unctuous matter, of a gray 

 colour, and peculiar, but not highly offensive, smell. According to 

 their position in the pits, for the bodies were deposited in pits or 

 trenches, about thirty feet deep, each capable of holding from twelve 

 hundred to fifteen hundred, and according to the length of time they 

 had been deposited, this transformation had occurred to a greater or 

 less extent. It was found to be most complete in those that were near- 

 est the centre of the pits, and when they had been buried about three 

 years. In such case, every part, except the bones, hair and nails, 

 seemed to have lost its properties, and to be converted into gras des 

 cimetieres, which was found to be a saponaceous compound, consisting 

 of ammonia, united to adipocire, a substance, as its name imports, 

 possessing properties intermediate between those of fat and wax. 

 When the adipocire was freed from the ammonia, and obtained in a 

 state of purity, it was found to resemble strongly spermaceti, both in 

 physical and chemical qualities. It was afterwards discovered, that 

 the conversion of muscular flesh into adipocire might be caused by other 

 means. Simple immersion, in cold water, especially in a running 

 stream, was found by Dr. Gibbes 2 to produce the conversion more speed- 

 ily than inhumation. It can be caused, too, still more rapidly by the 

 action of dilute nitric acid. 



The chemical is not the only interest attached to this substance. It 

 has been adduced in a court of justice for the purpose of enabling 

 some judgment to be formed regarding the time that a body may 

 have been immersed in the water. It is probable that this must differ 

 greatly according to various circumstances; as the period that elapsed 

 between the death of the individual, and the act of immersion; the 

 conditions of the fluid as to rest or motion, temperature, &c. ; and the 



1 Thouret, Journal de Physique, xxxviii. 255. 

 3 Philosophical Transactions for 1794 and 1795. 



