RESEARCHES IN ANIMAL CHEMISTRY. 
151 
Having operated on hundreds of pounds of meat, I have 
obtained a sufficient quantity of creatine to be able to sub- 
mit this substance to a thorough examination. 
Its physical properties have been given with such preci- 
sion by M. Chevreul, that I can add nothing to the descrip- 
tion given by this illustrious chemist. I think I can con- 
clude from my experiments that creatine makes part of the 
flesh of all animals. So far as 1 have gone I have shown it 
to exist in the flesh of beef, veal, mutton, pork, horse, hare 
and goat. The beautiful discovery of this able observer 
becomes still more important, since we cannot doubt that 
creatine plays a great part in the vital actions. It is at least 
certain that the bouillee of meat cannot be replaced either 
by gelatine, or by any other liquid extracted from another 
part of the organised animal, unless from the muscles. I 
have found creatine in the heart of the ox, but not in the 
brain, the liver, the lungs, or the kidneys. 
Creatine belongs by its crystallisation to the clinorhom- 
boidal system ; it forms tolerably large crystals, clear, trans- 
parent, and of great beauty; they lose at 100 degrees, 12.18 
for an 100 of water, which corresponds to two atoms. 
The results of numerous analyses have given me as the 
composition of crystallised creatine, the formula C 8 N 3 II 11 O 6 . 
Creatine is a neutral or indifferent body, which dissolves 
in alkaline liquids or weak acids, and may be again with- 
drawn without having undergone any change, but in pre- 
sence of acids or concentrated caustic alkalies, its properties 
are changed. 
In presence of energetic acids, creatine is transformed into 
an organic base, possessing very remarkable properties. 
The matter combined with the acid is no longer creatine, 
and can no more be transformed into this body ; it is a new 
body, which I shall designate creatinine, and which is 
formed in the presence of muriatic and sulphuric acids by 
the displacement only of four atoms of water. Analysis 
has given me for creatinine the formula C s N 3 Hr O 2 . Creati- 
