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proving soils artificially, the farmer cannot do better 
than imitate the processes of nature. 
The materials necessary for the purpose are sel- 
dom far distant : coarse sand is often found imme- 
diately on chalk ; and beds of sand and gravel are 
common below clay. The labour of improving the 
texture or constitution of the soil, is repaid by a 
great permanent advantage; less manure is required, 
and its fertility insured. And capital laid out in 
this way secures for ever the productiveness, and 
consequently the value, of the land. 
