t 558 ] 



borne in mind. The greater alkalinity is desirable not from 

 a mere manurial point of view, but from the fact that it 

 is the force of alkalinity which enables the ashes to rot 

 weeds and to ferment peat. It should be noted that the 

 Stassfurt salts of potash so largely used in Europe as 

 potash manures are inferior to ordinary wood-ashes for 

 manurial purpose, and there is no occasion for us in India 

 to look from Kainit and other Stassfurt salts. The ex- 

 planation seems to be that the sulphate and chloride of 

 potash of Stassfurt are devoid of the alkaline quality of 

 carbonate of potash which is the effective agent in ashes ob- 

 tained from wood, branches, leaves, &c. But merely as 

 a manure or plant food, potassium nitrate is the best 

 potash manure to use. For potatoes, tobacco, and beet, 

 nitrate of potash is now largely used, in Europe and America, 

 and we should all the more readily use it both as a Nitrogen- 

 ous and as a potash manure as it is a cheap manure for the 

 price at which it can be had in India. 



913. Physiological action of potash. -Potash plays 

 certain very important parts in vegetable physiology and 

 these may be mentioned here : 



(1) It has been found to be a means of enabling starch 

 to move from one part of the plant to another. This is one 

 reason why potash manures are found particularly adapted 

 for yams, 6l> potatoes and other root-crops which are valued 

 for their starch. The potash manure helps the freer circula- 

 tion of starch granules from leaves to roots. 



(2) Potash manures are helpful to fruit formation, especi- 

 ally formation of fruits containing sour juices, these fruits 

 containing citric, malic, tartaric or oxalic acid. In most cases 

 these acids are found combined with potash, Jails in Bengal 

 are required to grow lime trees. In Berhampore jail there were 

 hundreds of lime trees that had never borne fruits although 

 they were several years old. The jailor was advised to apply 

 ashes and bones. As there was objection on the part of the 



