64 GEINE. 



alkali, or its behaviour, as it is termed, is of the 

 highest importance to the farmer, and are to be con- 

 sidered in detail. 



110. The first and earliest product of decay, is 

 that which is so easily soluble in water (108). If 

 it could be at once seized upon, it would be, 

 doubtless, a perfectly colorless solution, but it chang- 

 es to a brownish color by exposure to air. This 

 character is very common in solutions of organic 

 matter. It is due in this case to the formation of 

 the insoluble variety of geine. The soluble passes 

 to the insoluble state. 



111. If a little alum is dissolved in the watery 

 solution of geine, and then a few drops of spirits of 

 hartshorn, or sal volatile, or as it is termed by chem- 

 ists, water of ammonia, are added, the earth alumi- 

 na will be let loose from the alum, and it will imme- 

 diately combine with, and precipitate the geine — that 

 is, little flocks fall down gradually in the liquor. 

 Hence, is derived an important character. Geine 

 has a great affinity for alumina. If lime had been 

 added to the solution of geine, the same effect 

 would have followed. The same effect would be 

 produced, by magnesia, by oxide of iron, and by 

 manganese. 



112. Alumina, lime, magnesia, oxides of iron, 



