CIIKM1STKY OF THK I, K I TO M A I \ KS. 343 



stands formed in the b<dy when there is an insufficient 

 air supply an 1 not eliminated in the exhaled air. 



r-air, according to observations made ly ODLINO, 

 contains a basic substance which is probably in com position 

 a com pon no! aiunionia. It contains, however, more carbon 

 than methylamine and less than ethylamine. 



It should be remarked that JACKSON has (Dee, 1887) 

 announced the presence in expired air of ((iiantities of car- 

 lion monoxide <i~as sufficient to produce the ill effects ordi- 

 narily attributed to the organic matter. The presence of 

 this poisonous gas must first be fully demonstrated l>efore 

 it can be taken into account in the consideration of the 

 toxieity of air ; certainly, even if present, it cannot explain 

 the results obtained by the French investigators as stated 



above, 



According to lLOSVA, expired air contains nitrous acid. 

 This may possibly be derived from that which is constantly 

 Ix HIM formed in the month, probably by the reduction of 

 nitrates ( MILLER). 



Lcucoma'i'nes of the Urine. 



A number of basic substances have IKVII isolated at 

 different times from the urine, and on that account they 

 may be properly classed as leiicoma'ines. Thus, LlEBREICH 

 (1869) found in the urine a base which apparently was an 

 oxidation-product of eholine, and which has since been 

 regarded as identical with U-taine. In 18GG DlJPRfc and 

 I>KN< K .IO.NK.S found, among other thing! in the urine, an 

 alkaloidal body which in sulphuric acid solution possessed 

 a bine fluorescence (see p. . %> >47). Most of the meml>ers of 

 the uric acid <;Tonp of leucoma'incs have Ix^en detected in 

 the urine and on account of their well-defined nature they 

 are described by themselves. In the urine and fo 

 cystinuria UDKANS/K v and BAUMANN discovered the well- 

 known ptomaines, cadaverine and pntrescine. For isola- 

 tion, sec j)|t. 207 and 208. 



In 1x7!), THUDICHUM annoumx-d the presence in the 

 urine of four new alkaloids, one of which, urotheobromine, 



