DIRECTIONS FOPw USING LIME. Ill 



It has a constant tendency to sink in the soil, and 

 in one that has been heavily limed for many years, 

 quite a layer of it exists in the subsoil: this may be 

 brought up by deep ploughing, or is made available 

 by drains, which permit the roots to go down. When 

 applied as a top dressing, it should in almost every 

 case be mild, and also when used in composts, where 

 much animal manure is present. The reason why pre- 

 caution should be used in the latter instance, is one 

 that has been alluded to before, in speaking of ma- 

 nures containing nitrogen. In all such cases, causti* 

 lime causes a formation of ammonia from the nitro- 

 gen, and a consequent escape of it into the air. Where 

 much lime is mixed with the manure, its depreciation 

 in value is very rapid, owing to this loss. Wliere 

 there is little or no nitrogen present, and it is desired 

 to decompose peat, or to rot heaps of weeds and turf, 

 the caustic lime is to be preferred, as its action is so 

 much more energetic. 



It is now considered the best practice to apply lime 

 in rather small quantities, and often, as then it is kept 

 near the surface, and always active. Where it is 

 bought, lime should always, if possible, be in the state 

 of quicklime, as in that case there will be neither 

 water nor carbonic acid to transport. In 100 lbs. of 

 carbonate of lime or common limestone, are 44 lbs. 

 of water; in 100 lbs. of slaked lime, about 25 lbs. of 

 water, so that the saving in both instances by carry- 

 ing quicklime is considerable. 



Numerous kinds of limestone, differing greatly in 

 purity, are found in various districts. In some sec- 

 tions they are all magnesian limestones or dolomites, 

 as these are called by mineralogists, containing, be- 

 side carbonate of lime, carbonate of magnesia. Where 

 the magnesia is in large quantity, it is decidedly inju- 

 rious, and in some cases is so much as to render the 

 limestone inadmissible for agricultural purposes, li 



