240 MANURES. 



he explains by the decomposition of the water ; at the same time 

 are produced aminoniacal sahs, amonj which are acetates and lac- 

 tates, whose acids are generated by the very act of fermentation. 

 As a striking example of the agency of water in the transit of azote 

 into the ammoniacal state in a quarternary compound, we may tak** 

 the putrefaction of urea. 



Urea is found in the urine of man and of quadrupeds ; its compo 

 sition, according to ]M. Dumas, is : 



Carbon 20.0 



Hydrogen 6.6 



Oxygen 26.7 



Azote 46.7 



lOU.O 



The animal substances dissolved in urine, as the mucus of the 

 bladder, &c., undergo, on contact with the air, a modification which 

 causes them to act upon urea like ferments. By their influence the 

 elements of water react upon this substance, and transform it into 

 carbonate of ammonia. 



Carbonate of ammonia is composed of: 



Carbonic acid 56.41, containing j OA>'p'e"n... .'.'.".."..'.. ....ll!^ 



Ammonia 43.59?containing . j ^l^^t\^^^!]\ W, [ W. [ W, [ "...^-^ 



But 100 of urea have been found to produce by fermentation 130 

 of carbonate of ammonia. 



Carbon. Hjrdroyen. Oxrjen. Atoit. 



Previom to fcrmentuion, lOOof urea ) oq qq 6 60 '2 67 46 7 



contains .... J " 



After frrmcnt-ition, 130 of carbonate i 20 00 10 00 53.3 46 7 



of ammonia contiins . . J ' ' 



Diirtrcncc Ol 3.4 26.6 0.0 



So that during its transformation, the urea has gained 3.4 of hy 

 drogen, and 26.6 of oxygen. 



In water the hydrogen is to the oxygen as 1 to 8. (: : 1 : 8.) 

 Now it is precisely in tbis proportion that hydrogen and oxygen 

 are found to l>e ac(}uired by the urea in passing into the state of ca' 

 bonate of ammonia ; whence it follows that the elemcnt-s of wave 

 are fixed in the process. 



Tbe putrefactuui of azotized substances is far from always pre- 

 senting results equally precise ; most frequently in decomposmg 

 they pass tbrough a series of changes, still very obscure, before 

 they attain their ultimate limit, viz. tbe production of ammoniacal 

 salts. Thus from putrefying caseum diffused in water, M. Hraconnoi 

 obtained, among other products and ammoniacal salts, a very remark- 

 able substance which he calls aposcpedine. 



Aposepeiline when purified is a white crystalline substance, soluble 

 in water and in alcohol, capable of combination with the metallic 

 oxides ; azote is one of its elements 



This substance, although engendered by the act of putrefaction, is 

 nevertbeless itself capable of jjiitrefying and giving birth to the last 

 products of the spontaneous decomjwsition of azotized matter. 



One of the most striking characteristics, at least that which i« 



