SARCOSINE. 147 



aqueous solution has a sweetish, sharp, faintly metallic taste, has 

 no action on vegetable colours, and is not affected by nitrate of 

 silver or corrosive sublimate ; with salts of the oxide of copper 

 it yields the same deep blue colour as is produced by ammonia. 

 According to Laurent and Gerhardt,* when fused with hydrated 

 potash, it yields, like leucine, hydrogen, ammonia, and carbonic 

 acid, but acetic in place of valerianic acid. (C 6 H 7 NO 4 + 3KO + 

 3HO=2KO.C0 2 +4H + H 3 N + KO.C 4 H 3 O 3 .) 



Composition. For the discovery and analysis of this body we 

 are also indebted to Liebig. In accordance with the above formula 

 calculated by Liebig,t it consists of: 



Carbon 6 atoms .... 40'45 



Hydrogen 7 .... 7'86 



Nitrogen I .... 1573 



Oxygen 3 .... 35'9f> 



100-00 



Its atomic weight=1112'5. 



It is worthy of remark that this body is isomeric with the 

 lactamide discovered by Pelouze, (see p. 89,) and the urethrane pre- 

 pared by Dumas from chloro- carbonic ether ; hence it is the more 

 important to ascertain the theoretical composition or the proximate 

 grouping of the atoms in these bodies. We might take the com- 

 monly accepted view that lactamide is amide with lactic acid 

 deprived of one atom of oxygen = H 2 N.C 6 H 5 O 4 , and according to 

 the hypothesis of Berzelius, regard sarcosine as a conjugated 

 ammonia= H 3 N.C 6 H 4 O 4 , which indeed is the most probable ; but 

 it is worthy of remark that lactamide, as has already been observed 

 in p. 89, is exhibited from lactide (a body isomeric with the adjunct 

 of ammonia in sarcosine) and ammonia; hence we should have 

 anticipated the formation of sarcosine, but not that of an amide. 

 The disintegration of lactamide by potash into lactic acid and 

 ammonia, and on the other hand that of sarcosine into acetic acid, 

 &c., would in itself be sufficient to show that these bodies were dif- 

 ferently constituted, even if their other properties did not prove it. 

 If, as Laurent and Gerhardt, as also Cahours,J expect, sarcosine is 

 actually decomposed by nitric oxide into lactic acid, then, seeing 

 that we are acquainted with actual lactamide, Piria's test for amide 

 would not prove very much, and the evidence of the amide-nature 

 of leucine and of glycine (which we are about to describe) would 

 fall to the ground. 



* Compt. rend. T. 27, pp. 256-25R. 



t Ann. d. Ch. u. Pharm. Bd. 62, S. 272. 



t Comp. rend. T. 27, pp. 265-268. 



L 2 



