94 • On the Agriculture of England^ Manures^ ^c. 



Cold, retentive clay soils are not so favourable for 

 summer fallow crops, or grain crops, as some other 

 soils ; yet even they have been frequently highly im- 

 proved by that practice in England, and the crops ob- 

 tained from them were much more luxuriant than they 

 had ever produced before, under the system of naked 

 summer fallowing; and the grass following those 

 crops was infinitely superior to any that had ever grown 

 previously on those lands, and as it clearly appears, 

 that those two wide extremes of soil, are capable of 

 being profitably managed, under a well directed sys- 

 tem of convertible husbandry, it will be useless to sub- 

 stantiate the capability of improvement, in the same 

 way, of the intermediate grades of soil ; — and although 

 iirst rate grass grounds, and those near cities or large 

 towns, and superior grazing, and dairy farms, may be 

 all profitably managed in their present state, yet if one 

 fifth part of those lands were annually cultivated, in 

 summer fallow crops, and another one fifth part in 

 grain, the remaining three fifths would produce more 

 grass than the whole, while laying in old pastures or 

 grass grounds, provided the soil was properly cultivat- 

 ed, in regular succession. 



The plough, in the hands of an inconsiderate farmer, 

 may be justly considered an instrument of certain and 

 speedy destruction, being capable of exciting the soil 

 to its utmost efforts of fertility, which naturally debili- 

 tates and exhausts it, when nothing has been returned 

 to renovate its powers, yet this same instrument, in the 

 hands of a judicious cultivator, who returns back to 

 the soil a due proportion of vegetation, which he can 

 readily gather, becomes the most powerful and rapid 



