[ 19° ] 



Where thefe manures cannot be had, coal-aflies, chips of wood, 

 burned clay, brick-duft, gravel, or even pebbles, are ufeful ♦; for 

 all thefe improve the texture, and the former fupply alfo the 

 carbonaceous ingredient. 



Before I advance farther, to prevent fuperfluous repetition 

 I {hall lay down a fecond general maxim, which is, that dung 

 is a proper ingredient in the appropriated manures of all forts of foils ^ 

 as it fupplies the carbonaceous principle. 



Of Clayey Loam. 



This foil is defedive either in the calcareous ingredient, or 

 in the fandy, or in both ; if in the firft, the proper manure is 

 chalk t; if in the fecond, fand; if in both, filiceous marie or lime- 

 ftone gravel, or effete lime and fand. 



The quantity of chalk that fhould be employed, confidered 

 abftradedly, fhould be diredly proportional to the defed of cal- 

 careous matter ; but as fuch a quantity cannot be added without 

 diminifhing the proportion of one of the other ingredients, a 

 much fmaller quantity muft be employed, or elfe a fubftance 

 which may convey fome proportion of the other ingredient. 

 The fame obfervation holds alfo with refpedl to fand ; thus we 

 have feen, in the laft chapter, a clayey loam, in which the fandy 



ingredient 



* 5 Bergman, 107. Young's Irilh Tour, 149, 129, 136. 

 f ift Young's Eaft. Tour, 395. 



