CHEMICAL BASIS OF THE ANIMAL BODY. 917 



Skatol. C 9 H 9 N (?). 



Noticed by Brieger 1 as one of the products of putrefactive changes in the small 

 intestine. Secretan 2 had previously described a similar substance as arising from 

 the putrefaction of albumin. 



Skatol is crystalline and contains nitrogen ; it is more soluble in water than indol, 

 and does not give rise to any red coloration with nitrous acid. 



Skatol readily passes into the urine when it occurs in the alimentary canal, and 

 then gives a violet-red reaction with strong hydrochloric acid. 



v. Nencki 3 prepares this substance by the putrefaction of a mixture of finely 

 divided pancreas and muscle substance. After the addition of acetic acid the 

 mass is distilled, when the skatol readily passes over. From the distillate it is 

 precipitated by picric acid, and the precipitate when again distilled with ammonia 

 gives off pure skatol, which may be finally purified by crystallization. 



[PTOMAINES AND LEUKOMAINES. 



These substances comprise the so-called animal alkalies, and belong to a class 

 of amines. They are called alkaloids because of their close resemblance in toxic 

 properties to the same class of substances obtained from plants. The difference 

 between ptomaines and leukomaines as classes is that the former are products of 

 abnormal metabolism and the latter of normal metabolism. Ptomaines are usually 

 highly toxic, while leukomaines are of feeble toxicity. It seems probable that in 

 specific diseases the disease germs form ptomaines and that the peculiar patholog- 

 ical states are due in a large measure to these substances acting as peculiar poisons.] 



1 Ber. d. Deutsch. chem. Gesell., Jahrg. x. (1877), S. 1027. 



2 Recherches sur putrefaction de 1'albumine. Geneva. 1876. 



3 Centralbl. f. d. med Wiss., 1878, S. 849. 



