CHAPTER VI. 



MINERAL MANURES. 



MINERAL manures are divided, for the sake of convenience? 

 into saline and earthy ; the former including pure salts whose 

 composition is exactly known, such as common salt and car- 

 bonate of soda ; and the latter including the various earthy 

 matters used to ameliorate the soil, such as lime, wood ashes, 

 and marl. The mineral manures are all supposed to have a 

 specific mode of action, which is "peculiar to each respectively: 

 the theory of their action, however, as fertilizers, cannot, for 

 want of space, except in a few cases, be detailed. But few, 

 comparatively, of the known mineral fertilizers are in common 

 use, and those only will be described. 



SALINE MANURES. 



Carbonate of soda. This salt, according to Johnston, is 

 beneficial on lands abounding in sulphate of iron, or overgrown 

 with mosses and other noxious vegetation ; and also as a top 

 dressing to fields of young grain, and wherever wood ashes 

 would be useful. It is said to be peculiarly beneficial to the 

 strawberry. From forty to sixty pounds may be applied to 

 an acre, either in powder mixed with other manure, or in 

 solution. 



Sulphate of soda, or Glauber's sail, has been used with 

 much benefit on fruit trees, rye, beans, beets, and some other 

 crops. The quantity used should be at least one hundred 



