PROTEINS. 67 



joint office for organic and physiological chemistry if it is capable 

 of performance by the present methods of technique. Even Fischer, 

 however, is frank enough to say that the production of the great 

 body of protein substances synthetically, will, under the most en- 

 couraging conditions, be a terrific task, involving the " life-work of 

 a whole army of inventive and diligent chemists." 



For the benefit of those especially interested in such matters a 

 photograph of the Fischer apparatus (Fig. 22, page 71) used in 

 the fractional distillation, in vacuo, of the esters of the decompo- 

 sition products of the proteins, as well as micro-photographs and 

 drawings of preparations of several of these decomposition products 

 (Figs 19 to 31, pages 68 to 81) are introduced. For the prepara- 

 tions and the photograph of the apparatus the author is indebted 

 to Dr. T. B. Osborne, of New Haven, Conn., who has made many 

 important observations upon the hydrolysis of proteins. The repro- 

 duction of the crystalline form of some of the more recent of the 

 products may be of interest to those viewing the field of physio- 

 logical chemistry from other than the student's aspect. 



An extended discussion of the various decomposition products 

 being out of place in a book of this character, we will simply make 

 a few general statements in connection with the primary decompo- 

 sition products. 



DISCUSSION OF THE PRODUCTS. 



Ammonia, NH 3 . Ammonia is an important decomposition 

 product of all proteins and probably arises from an amide group 

 combined with a carboxyl group of some of the amino acids. It 

 is possible that the dibasic acids, aspartic and glutamic, furnish 

 most of these carboxyl groups. This is indicated by the more or 

 less close relationship which exists between the amount of ammonia 

 and that of the dibasic acids which the several proteins yield upon 

 decomposition. The elimination of the ammonia from proteins 

 under the action of acids and alkalis is very similar to that from 

 amides like asparagine. 



Glycocoll, C 2 H 5 NO 2 . Glycocoll, or amino acetic acid, is the 

 simplest of the amino acids and has the following formula : 



NH 2 



I 

 H-C-COOH. 



I 

 H 



