CRENIC AND APOCRENIC ACID. 81 



126. Not less important to the farmer are the relations of 

 geine to alkalies, its solubility is wonderfully increased by 

 their action ; this is a most valuable, because available prop- 

 erty ; it allows the farmer to bring into use, by the applica- 

 tion of alkalies, the geine, which, in its insoluble state, is 

 quite valueless. This remarkable property is not confined 

 to that portion of geine which, it may be supposed, is chem- 

 ically combined with alkali. Alkali, by the mere action of 

 presence, by its catalytic action, which will be hereafter ex- 

 plained, renders an indefinite, but large quantity of geine 

 soluble in water. This is a principle of high practical value, 

 and were the results of the principles detailed in the fore- 

 going pages to terminate in this fact, that alone rightly pon- 

 dered, would account for a vast number of facts in vegetable 

 physiology, and lead to new views in the pursuit of agricul- 

 ture, not less important than practical. 



The organic matter of soil contains within itself the ele- 

 ment of its own partial solution, that is, ammonia. This is 

 generally combined, as has been shown (101), with crenic 

 and apocrenic acids. Of the seven organic matters found in 

 soil, these acids compose the smallest proportion. Their 

 importance, however, is in the inverse ratio to their quan- 

 tity. Their properties require a distinct account, allied as 

 they are, for the most part, to those of the other geine acids. 



Crenic and apocrenic acids are many -based acids ; that is, 

 they saturate several proportions of one base, or one pro- 

 portion of several bases at once. 



Crenic acid saturates four, and apocrenic acid five equiva- 

 lents of bases. Compound salts are thus formed by these 

 acids, with the various alkaline, earthy and metallic bases 

 found in the soil. Thus, one proportion of apocrenic acid 

 may be found with one of ammonia, one of potash, one of 

 lime, one of iron, one of magnesia. These, by their union, 

 4. 3f 



