20 FERTILISERS AS AN AID TO 



7. Without sufficient lime in the soil, 

 chemical fertilisers, which are the main- 

 stay of profitable cultivation, cannot 

 exert their full benefit. 



When a soil contains less than i per cent, 

 of carbonate of lime in the surface soil, it is 

 getting near danger point, and will 

 sous needing be grea tly benefited by "liming." 



The actual percentage is easily 



ascertained by a chemical analysis, which every 



farmer who is in doubt should have made ; 



they are now so inexpensive as to be within 



the reach of all. The presence of certain plants 



or weeds also denotes the deficiency of lime, as, 



for instance, spurrey, sorrel, corn marigold, the 



foxglove, bracken, heather, and gorse, also the 



absence of leguminous herbage in the pastures. 



Lime can now be readily obtained in the form 



of powder, either as ground freshly burnt lime, 



or as carbonate of lime (ground 



limestone or chalk), to which state 



burnt or caustic lime reverts in the 



soil. Ground lime is to be preferred on all clay 



soils or damp sour land, applied at the rate of 8 



to 10 cwts. per acre, which will usually be found 



sufficient for four or five years. On 



the lighter soils, such as sands and 

 Chalk, Marl. i r i i i 



gravels, finely ground limestone, 



chalk, or marl, should be used in preference, as 

 they are milder in their action. Of the two 

 former, double the quantity will be necessary, as 

 they are only equivalent chemically to about 

 half their weight of caustic lime, or about i ton 



