72 ESSAYS AND OBSERVATIONS 



believe, that roots are always in the mod 

 advantageous (ituation vv^here nature pla- 

 ces rliem ; and that, accordingly, a plant 

 thrives bell with downward roots, where 

 nature gives them that diiedlion. If 

 this proportion hold, to which we may 

 trult till the contrary be demon ftraied by 

 experiments, it folio a^s, that Ihallow 

 ploughing is proper for thof.- plants only 

 which extend their loots horizoutally. 



B'JT as, befide lateral or horizontal 

 roots, the bulk of vegetables pufh ma- 

 ny roots downward much deeper than 

 three inches, the benefic of deep plough- 

 ing for thefe plants will appear from 

 the following confiderations. 



In the jirjl place, it gives room for the 

 roots to fxtend themfelves according to 

 the dire6lion of nature, which, it is pre- 

 fumed, will contribute to the vigor of 

 the plant. This argument goes upon the 

 fuppoiition, that the loil, as far as pier- 

 ced by the plough, is proper for vegeta- 

 tion, either naturally, or made fo by cul- 

 ture J and it mull be kept in view, that 



every 



