210 ARTIFICIAL MANURE. 



process is generally over, a part of the ammonia remains, 

 still evident to the senses by adding caustic potash. It exists 

 in part, either as a compound of crenic and apocrenic acid, 

 or other forms of geine, or as phosphate of ammonia, and 

 when the presence of ammonia is added to the salts, whose 

 existence has already been pointed out, it may be said that 

 peat approaches dung moistened with the liquid evacuation 

 of the animal. 



261. The power of producing alkaline action, on the insol- 

 uble geine, is alone wanted to make peat as good as cow- 

 dung. Reviewing the various matters, from whatever source 

 derived, solid or liquid, which are used as manure, all possess 

 one common property, that of generating ammonia. The 

 conclusion then of this whole matter is this: the value of all 

 manures depends on salts, geine, and ammonia; and it is di- 

 rectly in proportion to the last ; it follows, that any substance 

 affording these elements may be substituted for manure. 



262. The great question com^s. How is to be given to 

 peat, a substance which, in all its other characters, is so nearly 

 allied to cow-dung, that lacking element ammonia *? How is 

 that to be supplied 1 Without it, cow-dung itself would be 

 no better than peat, nay, not so good; for in peat, nearly one- 

 half of the geine is already in a soluble state. Passing by 

 the fact, already alluded to, that peat contains traces of am- 

 monia, which, evolved when treated with caustic potash, 

 exerts its usual action, it may be added that, possibly in the 

 process of vegetation, when the decomposing power of the 

 living plant is exerted on peat, and the silicates, caustic pot- 

 ash is produced, and ammonia evolved. Considering peat 

 as a source of nitrogen only, it is evident that the action of 

 alkali is of the highest practical importance. 



263. In this part of the subject of manure, probabilities 

 and possibilities are no longer admissible. There are two 



