136 Royal Society : — 



gave on analysis the composition C"^H^N''0'*, wliicb is that of 

 xanthic oxide. 



Neglecting the intermediate nitrogenous products, the trans- 

 formation of guanine into xanthine may be thus represented : — 

 C'° tP N'^ OH 03=C>o H-* N^ 0'' + HO + N. 



Guanine. Xanthiue. 



Xanthine does not lose weight when heated even to 100° or 150". 

 Its solution gives precipitates with corrosive sublimate, with 

 acetate of copper, and with nitrate of silver. Its ammoniacal 

 solution gives precipitates with an ammoniacal solution of chlo- 

 ride of zinc or of chloride of cadmium. 



Its basic properties are even less strongly pronounced than 

 those of guanine or of sarcine. Strecker further found that 

 xanthine is contained in small quantities as a normal constituent 

 of urine. It may be separated by taking advantage of its pro- 

 perty of forming a precipitate with acetate of copper or nitrate 

 of silver. 



XXV. Proceedings of Learned Societies. 



ROYAL SOCIETY. 



[Continued from p. 77-] 



February 3, 1859. — Sir Benjamin C. Brodie, Bart., President, in 



the Chair. 



THE following communications were read : — 

 " On the Aquiferous aud Oviductal Systems in the Lamelli- 

 branchiate Mollnsks." By George RoUeston, M.D., Lee's Header 

 in Anatomy, and Charles Robertson, Esq., Curator of the Museum, 

 Christ Church, Oxford. 



" On the Action of Nitric Acid and of Binoxide of Manganese and 

 Sulphuric Acid on the Organic Bases." By A. Mattbicssen, Th.D. 



In the Proceedings of the Royal Society (vol. ix. p. 118), I stated 

 that by the action of nitrous acid on aniline I had obtained ammonia 

 and nitropbeuasic acid ; since then I have acted on several other of 

 the organic bases with the same reagent, as well as with nitric acid, 

 and with binoxide of manganese and sulphuric acid ; aud I will now 

 shortly enumerate the experiments. 



1 . Action of Nitrous Acid on Amylaniline. 

 The dilute solution of the nitrate of amylaniline was acted on by 

 nitrous acid at 100° C. for 12 hours. Amylaniline and ammonia 

 were obtained, but in quantities too small to be quantitatively 

 determined. 



2. Action of Nitric Acid on Amylaniline. 

 Amylaniline was boiled with dilute nitric acid ( I part acid to 2 of 



