298 A WORD ABOUT MANURES. 



fields to a high state of productiveness. There are reasons 

 for all these assumptions, but Space forbids their mention. 



Many things contains salts available to the agricul- 

 turist. - Lime, ashes, plaster of Paris, (sulphate of lime), 

 saltpetre, common salt, phosphate of lime, bone dust, coal 

 ashes, hair, hoofs, horns, copperas and many others. Some 

 of these substances have to be used sparingly, such as salt 

 or copperas, but all are beneficial to growing plants. 



'These substances act chemically, and free a great many 

 inert matters. Growing plants absorb vast quantities of, 

 carbonic acid, through their leaves, and carrying it down, 

 throw it into the soil, where it acts upon silica and allumi- 

 na freeing salts for their growth. 



Wood and coal ashes are very rich in the salts, and furn- 

 ish one of the cheapest and best additions that can be made 

 to land. Coal ashes are not so rich in the various salts, 

 but contain enough to merit a better fate than is generally 

 awarded them. 



The composition of wood ashes is as follows : 



200 parts of unleached wood ashes contain, 



Carbonic acid, 58.53 



Sulphuric acid, s . 6.43 



Phosphoric acid, 3.40 



Muriatic acid, 1.82 



Lime, : 50.35 



Magnesia, 4.55 



Potash and soda, 67.96 



Silex, 5.22 



Oxide iron, 50 



Oxide Manganese, 1.10 



Water, 14 



200.00 



Of this 27.14 parts are soluble at once in water, and 



leached ashes are deprived of it, and the balance, 172.86 



parts are insoluble, but act slowly on the soil freeing various 



