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C.LA.YEY foils are defedive both in conftitutlon and in texture; 

 they want the calcareous ingredient and coarfe fand. Calcareous 

 marie fupplies the calcareous ingredient chiefly : limeftone gravel 

 both. The other marks fupply them in a lefTer degree. If the 

 clay be analyzed, and its proportion of fand and argil 1 known, the 

 fpecics of marie moft advantageoufly applicable may be deter- 

 mined ftill better ; for inftance, if the argill notably exceeds or 

 even amounts to the proportion of 40 or 50 per cwt. calcareous 

 marie or limeftone gravel are the beft improving manures, as 

 they contain moft of the calcareous ingredient ; but if the filiceous 

 ingredient amounts to 75 or 80 per cwt. as it fometimes doeSi 

 argillaceous marie is moft fuitable. 



A mixture of marie and dung is ftill more advantageous *, 

 becaufe the dung fupplies the carbonaceous ingredient. But 

 the marie muft be ufed in the fame quantity as if dung had not 

 been applied, otherwife the operation muft be more frequently 

 repeated. How the quantity of marie or other manure can be 

 efti mated I fhall prefently fhew. 



If marfe cannot be had a mixture of coarfe fand and lime 

 perfedlly effete or extinguifhed, or chalk, will anfwer the fame 

 purpofe, as it will fupply the defedive ingredient and open the 

 texture of the clay ; fo alfo fand alone, or chalk, or powdered 

 limeftone, may anfwer, though lefs advantageoufly. Lime alone 

 appears to me lefs proper, as it is apt to cake and does not 

 fufficiently open the foil. 



: ,(; Where 



• 4th Young's Eaftern- Tour, 404. 



