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The deficiency in lime or calcium salts is particularly marked 

 and is greatest in the peat formations of the coast overlying clay sub- 

 soils. 



As is well-known, the peaty soils are very sour or acid in 

 character when first opened out and the drainage water remains acid 

 for months or even years afcer such lands are first opened out for 

 cultivation. 



The Advantages of Liming. 



{a) Peaty Lands: — In earlier days of agricultural practice in 

 Europe, peaty lands were first opened out by through 

 drainage, to carry off the excess of water and to aerate and 

 dry the soils. 



' The surface was then broken up by ploughs and the 



earth heaped together and burnt, the combustion being 

 allowed to proceed slowly. In this way the mineral con- 

 stituents were increased proportionately and the acidity of 

 the soil was neutralised by the alkaline ashes — chiefly 

 carbonates of the alkalis (soda, and potash) formed by 

 burning the organic salts of these substances. 



The great disadvantage of such a process is the loss 

 of nitrogen in the organic matter of the soil. 



This method has now been replaced by thorough drain- 

 age of land in such cases, the land after drainage being 

 allowed to remain for some considerable time, in order to 

 become consolidated, since, as is well known, and can be 

 easily observed in the peaty soils in our coast districts, 

 considerable shrinkage takes place when such land is 

 opened out, and the land frequently sinks a foot or even 

 more in many cases. The soil is then thoroughly limed 

 to neutralise any acidity and to render the essential con- 

 stituents more available for the plants subsequently 

 cultivated on the land. To show the effect of lime on peaty 

 land it is only necessary to collect the dark brown peaty 

 drainage water and add to it a little lime water or solid 

 lime — when, on standing for about 5-10 minutes, the whole 

 of the organic matter is precipitated and a clear colour- 

 less water left. 



^b/ Clay Lands: — Clay soils were originally improved in a 

 similar way, the clay after ploughing being heaped together 

 with organic debris and slowly burnt at a low temperature. 

 The physical texture of clay soils is improved in this way. 

 The same disadvantage in the application of this method 

 to clay soils exists as in the case of peaty soils, i.e., loss 

 of organic nitrogen. 



