Chap. IX. O F P L O W I N G. 53 



mingled, and the mould becomes fine and dufty. You muft be 

 doubly careful in this operation upon your light lands, which ought, 

 by the harrow, to be laid as fmooth and level as a table. 



About the beginning of Auguft will come on yonv feed-ploiv'mg, 

 properly fo called upon thefe light lands, becaufe you muft here 

 plow and /010 together. 



Authors give directions for plowing lands into many diTerent 

 forms, moftly arifing from the different natures of foils, but too 

 often from the particular long eftablifhed cuftom of countries, with- 

 out fufficiently entering into the reafon of it. 



Light foils are always plowed into broad lands, unlefs a very flat 

 firuation. renders it neceflary to plow into narrow ftitches for wh^at. 



Strong foils are, without exception, advifed to be plowed into 

 narrow ridges. 



It would be moft advifeable, always to lay the ground level, and 

 without ridges, where prafticable. In fummer fallowing, it might 

 be ufed to great advantage even in clay lands. 



In plowing wet land, for winter fallowing, I anr not certain whe- 

 ther the beft way would not be, inftead of Cngle bouts or narrow 

 ridges, to make the ridges very broad, and lay them up high : for 

 if the ground is level, the water will lie in the parting thoroughs, 

 and by foaking into the fides of the ridges, make it fo poachy, as 

 to render it very unfit to be worked, till late in the fpring, unlefs 

 the feafon is very dry ; or, if there is much defcent, great part of 

 the beft foil will be carried off. 



We now return to Mr. Duliamel, who proceeds thus : 



Mr. Tull fays, the produce of the earth is increafcd by raifing the 

 ridges high, becaufe the furface is thereby enlarged. As he infifts 

 greatly on this point, we cannot help mentioning his reafons, and 

 thofe which induce us to differ from him. 



He was fenfible it would be objecled to him, that the produce oi 

 a floping furface is not greater than that of a plane equal in extent 

 to the bafe of the flope : for the plants growing perpendicular to 

 the horizontal bafe, there is no point of the flope, which does not 

 anfwer vertically to a point of the horizontal bafe. 



But he maintains, that the produce of the earth is in proportion 

 to the inclined or floping furface ; becaufe the roots have a greater • 

 extent of earth to draw their nourifhment from ; and becaufe the 

 ears of corn rifing one above another, in the manner of an amphi- 

 theatre 



