Wood Ashes 



little phosphoric acid by incineration, wood ash 

 can be used on tobacco. It is kno\vn that tobacco 

 bums in direct proportion to the potash which it 

 contains, and inversely in proportion to the chlorine. 



Birch ash is poor and beech relatively poor in 

 potash — 10 per cent., and 6 per cent, phosphoric 

 acid. Oak is a little richer ; but poplar is as rich in 

 potash as kainite — 12 to 13 per cent., and also con- 

 tains 10 per cent, phosphoric acid, while elm is 

 very rich, containing 20 per cent, or more of potash. 

 Pine, which contains about 10 per cent, of potash, 

 is poor in phosphoric acid, only containing 4 per 

 cent. 



As a whole wood ash contains from 5 per cent, to 

 25 per cent., with an average of 8 per cent. It 

 forms an excellent potassic manure frequently 

 employed as a top dressing after the first cutting of 

 clover, also on grass land, where it tends to promote 

 clovers. On beans it is also very useful. 



Formerly, by washing and purifying the ash, 

 pearl ash was produced, which was at that time the 

 source of POTASH. Ash also furnished the base 

 which fixed the nitric acid formed in the nitre beds, 

 whence was obtained the nitrate of potash used in 

 the manufacture of gimpowder. 



Wood Ashes. 



These are relatively abundant on farms where 

 big hedges are used. The ashes should be sheltered 

 from rain to preserve the potash. They are valu- 

 able chiefly for their potash, and less so for their 

 phosphoric acid and carbonate of lime, of which 

 there is only a small quantity. Potash is found in 



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