460 M. Dumas on the Chemical Statics of Organized Beings. 



ammoniacal salts which rain water itself contains, are not al- 

 ways sufficient. With regard to most plants, the cultivation 

 of which is important, their roots should also be surrounded 

 with azotated manure, a permanent source of ammonia or of 

 nitric acid, which the plant appropriates as they are pro- 

 duced. This, as we know, is one of the great expenses of 

 agriculture, one of its great obstacles, for it possesses only 

 the manure which is of its own production. But chemistry is 

 so far advanced in this respect, that the problem of the pro- 

 duction of a purely chemical azotated manure cannot be long 

 in being resolved. 



M. Schattenrnan, the skilful director of the manufactories 

 of Bouxvilliers in Alsace, M. Boussingault and M. Liebig, 

 have turned their attention to the functions of ammonia in 

 azotated manures. Recent trials show that the nitric acid of 

 the nitrates also merit particular attention. 



But for what purpose is this azote, of which plants seem to 

 have such an imperious want? M. Payen's researches partly 

 teach us, for they have proved that all the organs of the 

 plant, without exception, begin by being formed of an azotated 

 matter analogous to fibrine, with which at a later period are 

 associated the cellular tissue, the ligneous tissue, and the amy- 

 laceous tissue itself. This azotated matter, the real origin of 

 all the parts of the plant, is never destroyed; it is always to 

 be found, however abundant may be the non-azotated matter 

 which has been interposed between its particles. 



This azote, fixed by plants, serves therefore to produce a 

 concrete fibrinous substance which constitutes the rudiment 

 of all the organs of the vegetable. 



It also serves to produce the liquid albumen which the coa- 

 gulable juices of all plants contain, and the caseum, so often 

 confounded with albumen, but so easy to recognize in many 

 plants. 



Fibrin, albumen and caseum, exist then in plants. These 

 three products, identical in their composition, as M. Vogel 

 has long since proved, offer a singular analogy with the lig- 

 neous matters, the amidon, and the dextrine. 



Indeed, fibrin is like ligneous matter, insoluble ; albumen, 

 like starch, coagulates by heat ; caseum, like dextrine, is so- 

 luble. 



These azotated matters moreover are neutral, as well as the 

 three parallel non-azotated matters ; and we shall see that by 

 their abundance in the animal kingdom they act the same part 

 that these latter exhibited to us in the vegetable kingdom. 



Besides, in like manner as it suffices for the formation of 

 non-azotated neutral matters, to unite carbon with water or with 



