260 AMMONIA. [BOOK n. 



products of the pancreatic digestion of 3000 grammes of moist fibrin, 

 28 grammes of the chemically pure platinochloride of lysine, besides 

 enough of the silver compound of lysatinine to establish its identity. 

 Further, from 150 grammes of Kiihne's dry pancreas, Hedin obtained 

 0'7 grammes of the pure platinochloride of lysine, which enabled 

 the identity of the body to be determined by elementary analysis, 

 and doubtless lysatinin was also present 1 . 



Ammonia: NH Q . 



When albuminous substances are split up by the action of 

 Ba(OH) 2 at high temperatures (Schiitzenberger's process) products are 

 obtained of which some, such as leucine, tyrosine and aspartic acid, 

 are probably primary, i.e. are produced directly by the splitting-up 

 of the proteid molecule, whilst others, such as acetic, oxalic and 

 carbonic acids, are secondary, i.e. are produced either by the simple 

 decomposition or by the oxidation of bodies which were the primary 

 results of decomposition but are not able to remain undecomposed 

 under the particular conditions. Thus it has been shewn that a 

 part, if not the whole, of the carbonic acid obtained by Schtitz- 

 enberger must be derived from the secondary decomposition of 

 lysatinine, itself a primary product of the splitting-up of proteids. 

 In judging of the primary or secondary relations of these products of 

 decomposition very great stress must be laid upon the evidence 

 which establishes whether the body under consideration is formed, 

 whichever the method of decomposition. 



Amongst the products obtained both by Schiitzenberger's method 

 of decomposition and by that followed by Hlasiwetz and Habermann, 

 Drechsel and others (Sn C1 2 and HC1), NH 3 occupies a constant 

 place. It was, therefore, interesting to determine whether, under the 

 influence of trypsin, ammonia is formed. The question has been 

 decided in the affirmative. In an investigation made in Hoppe- 

 Seyler's Laboratory, under conditions which exclude the probability 

 of putrefactive changes, in trypsin digestions which lasted a very 

 short time (4 hours), and in which the temperature was only 32 C., 

 small quantities of NH 3 were rapidly formed 2 . 



Stadelmann 3 , in Ktihne's laboratory, repeated Hirschler's experi- 

 ments under conditions which absolutely excluded the possibility of 

 putrefaction and obtained exactly the same results. 



1 Dr S. G. Hedin, ' Zur Kenntniss der Producte der tryptischen Verdauung des 

 Fibrins.' In Drechsel's ' Abbau der Eiweissstoffe.' 



~ Dr August Hirschler, 'Bildung von Ammoniak bei der Pancreasverdauung von 

 Fibrin.' (Aus dem physiologisch. chemisch. Laborat. in Strassburg.) Zeitschrift f. 

 phys. Chemie, Vol. x. (1880), pp. 302 305. 



3 E. Stadelmann, 'Bildung von Ammoniak bei Pankreasverdauung von Fibrin,' 

 Zeitschrift f. Biologie, Vol. xxiv. (1888), pp. 261266. 



