FEKMENTATION 215 



(sodium salt) had been added. The blood passed 

 through the kidney 9-10 times. 



Upon analysis, there appeared 0.087 gram benzoic 

 acid, produced from 0.1276 gram hippuric acid. 



Synthesis of Hippuric Acid by Histozyme. A pig's 

 kidney was perfused three hours with one litre defibri- 

 nated pig's blood containing a neutral solution of 0.5 

 gram benzoic acid and 0.6 gram glycocoll. The blood 

 passed ten times through the kidney. 



Found : 94 mgm. hippuric acid. 1 



These actions depend upon a ferment, histozyme, 

 extracted by Schmiedeberg. 



Some hypothetical considerations will be of value 

 here. Compounds of carbon may be divided into 

 those in which the carbon atoms are arranged in an 

 open chain, for example ethane, C 2 H 6 , 



H H 

 H C C H 



u 



ETHANE 



and those in which the chain is closed to form a " car- 

 bon ring," for example, benzene, C 6 H 6 , which consists 

 of six carbon atoms, in a closed, ring-shaped chain, the 

 " benzene nucleus," with a hydrogen atom joined 

 to each carbon atom by its fourth affinity (Kekule, 

 1865). 



1 Schmiedeberg : Archiv fiir experimentelle Pathologic und 

 Pharmakologie, 1881, xiv, pp. 382-383. 



