[389] SCIENTIFIC MANUAL. 103 



vals, while in others smaller applications are made, at 

 shorter intervals. 



In portions of England, as much as 250 to 300 bushels 

 of slaked lime are sometimes applied per acre, followed 

 by applications of from 8 to 20 bushels every four or six 

 years, according to circumstances. Larger applications 

 may be made to stiff clays than to sandy soils, and in 

 either case the quantity should depend somewhat upon the 

 depth of the soil, and the amount of vegetable matter it 

 contains. Again, since vegetable matter decomposes 

 more rapidly in warm than in cold climates, larger applica- 

 tions are generally admissible to soils in the latter than 

 in the former. 



Lime should be invariably applied broadcast, and thor- 

 oughly incorporated with the soil, if applied without pre- 

 viously composting with vegetable matter. 



Lime should never be composted with animal manures, 

 or other substances containing a considerable percentage 

 of nitrogen. If composted with such material, the loss of 

 ammonia will result. 



To secure the full benefit of liming, the soil, if not natur- 

 ally so, should be first thoroughly under-drained. 



If marls are used, the quantity applied per acre should 

 depend upon the per cent, of carbonate of lime they con- 

 tain, and upon the physical character of the marl used, as 

 regards its pulverulent condition or the facility with which 

 it crumbles before or soon after its application to the soil. 



The necessity of an application of lime to any particular 

 soil, may be determined to some extent, by the character of 

 the spontaneous growth, but more accurately by experi- 

 ment on a small and comparatively inexpensive scale. 



Another, and very important form in which lime occurs 

 in nature, is in combination with sulphuric acid, known to 

 the chemist as sulphate of lime, and to commerce as gyp- 

 sum, ground plaster and land plaster. 



