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In addition to the advantages of improved physical 
texture in both cases, there is no doubt, in the light of 
recent discoveries, that the well known effect of this 
burning was partly due to the partial sterilization of the 
soils which subsequently increased the bacterial flora. 
This no dotfbt occurs to a considerable extent when 
virgin jungle is felled and burnt in countries such as the 
Federated Malay States, as, although probably in some 
parts the beneficial and other bacteria are completely 
killed by the high temperature on the surface, the tempera- 
ture at a depth of say one foot would be only sufficient 
to partially sterilize the soil and thus give rise to the 
benefits of such a process. Clay soils are improved to a 
remarkable extent by liming — the effect being principally 
an improvement of the texture of the soil. 
The finer soil particles are coalesced by the addition of 
lime and lime salts and become flocculated into large 
particles, so that such soils after treatment become more 
open in texture, retain less water, which is often a desi- 
deratum in this country, particularly in flat lowly ing lands. 
(A simple experiment nan be easily carried out to 
demonstrate this flocculating effect of lime on colloidal 
clay particles. Two tall glass cylinders are taken and in a 
separate vessel a mixture of clay and water is made. The 
supernatant liquid from this mixture is then decanted into 
the two cylinders— the liquid contains only the finest clay 
particles which remain suspended in the water, for the most 
part for an indefinite length of time. If a trace of lime, 
slaked or quicklime or a solution of lime water be added to 
one of the cylinders, the whole of the clay particles sus- 
pended in the cylinder will quickly fall as a sediment to 
the bottom of the liquid leaving a clear liquid above. 
This experiment is simple and elementary but very 
instructive). 
Clay soils after treatment with lime are more easily 
cultivated and do not crack or cake when dry. 
(c) Sandy Soils : — Although it may appear somewhat paradoxi- 
cal, lime has also a beneficial action on light sandy soils, 
rendering them more cohesive by cementing the loose 
particles together. This is easily understood when we 
consider the use of lime as a binding agent in the prepara- 
tion of mortar. 
General Effects of Lime. 
The general effects of the application of lime can be conveniently 
classified as follows : — 
1. Mechanical or Physical. 
2. Chemical. 
3. Biological. 
