AGRICULTURE WITH CHEMISTRY. 173 



submitted to the same barbarous system of hus- 

 bandry. 



The other division of the arable land consisted of the 

 infield or croft land, to which the whole dung produced 

 on the farm was exclusively applied. By this mode of 

 treatment, these last mentioned lands were made fertile 

 at the expence of the others ; and by a repetition of this 

 pradtice for many centuries, a superabundance of vege- 

 table matter has therein been accumulated. Too great a 

 proportion of inert vegetable matter causes ground of 

 this description to be too loose and open for most kinds 

 of grain ; particularly for winter corn, which, by the 

 alternate changes from frost to thaw, and vice versa, is 

 liable either to be destroyed or spewed out of the 

 ground. 



Black infield mouldof this description, especially when 

 it contains a due proportion of calcareous matter, pro- 

 duces a rich and luxuriant herbage : it should therefore 

 be kept in a i)roper rotation of pasture and tillage, and 

 not in tillage alone, as is still the prevailing practice in 

 many parts of Scotland. 



By 



