Lime 



limekilns, either ground or not according to the name 

 it bears. Very often it is slaked lime [Ca(0H)2] 

 carbonated by contact with the air, losing in con- 

 sequence the greater part of its value. This being 

 the case it is absurd that it should sometimes be 

 sold at a higher price than lump lime, which is really 

 valuable. Lime ought to be in as large lumps as 

 possible, providing that it can be well burnt, because 

 in this state it is less exposed to the air. Even if it 

 is well applied, ground lime cannot saturate all the 

 acids of the soil, bum organic matters, or in many 

 cases promote nitrification. In fact, it might give 

 rise to a new proverb, "Agricultural lime im- 

 poverishes those who employ it, and enriches those 

 who produce it." 



Agricultural lime sometimes contains large quan- 

 tities of impurities derived from the limestone itself 

 and from the coal used for burning. About 50 per 

 cent, of these impurities have been found in some 

 cases. If such a sample were slacked and afterwards 

 carbonated its weight would be much increased by 

 carbonization and absorption of water, and its value 

 considerably diminished. Therefore the contents 

 and form of lime should be guaranteed. This typical 

 case might be illustrated by the following figures. 



We will take a farmer, living a long way from the 

 limekiln, and, say, five miles from the station : 



Quicklime m lump costs 17s. a ton at the kiln. 



Agricultural or groimd lime costs 17s. 6d. a ton 

 at the kiln. 



To get equal value from each he must use two tons 

 of agricultural lime per acre, or only about half a 

 ton of quicklime per acre. 



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