OF THE COUNTY OF DOWN. 65 



medy the defefts of the latter, as well as of the for- 

 mer, which will appear more clearly by confidering 

 the defefts of each. In ftrong land the natural pores, 

 or interfaces, are too fmall, the artificial ones are too 

 large ; this defect is increafed by infufficient tillage ; 

 of this moft farmers of any experience are aware, and, 

 by the different operations of hufbandry joined with 

 manure, endeavour to open what is too clofe, to admit 

 the paflage of the roots in its natural flate, and to 

 clofe what is too open to afford the necefTary preffure. 

 Strong ground breaks into clods or lumps, when badly 

 tilled ; roots cannot penetrate into, but get between 

 thefe, where they perifh for want of nourifhment. 

 Light land has its natural, as well as its artificial pores, 

 too large. Pores, that are too large in any land, can be 

 of little ufe to roots, except to afford them a paffage to 

 other cavities more proper for them ; for if, in any 

 place, they lie open to the air, they are dried up and 

 fpoiled before they reach them ; for no root can take 

 in any nourishment from any cavity, unlefs it comes in 

 contact with, and paffes againft the fuperficies of that 

 cavity, which includes it j but a root is not preffed by 

 the fuperficies of a cavity, whofe diameter is greater 

 than the root, and confequently it cannot be nourifhed 

 therein. From this ftatement we find, that ftrong land 

 requires to be opened, for the admiflion of roots ; light 

 land to be clofed, to prevent their paffing too frely, 

 and without a proper degree of prefTure ; the great 



K object 



