140 On the Application 



vegetable mould present in them. If the amount of this ingre- 

 dient be not more than J per cent, the soils are called poor, as 

 the fertility of a soil is in all cases greatly influenced by the 

 proportion of this ingredient ; if it varies from 0*5 to 1*5 per 

 cent., it is called intermediate; if from 1 • 5 to 5*0 per cent., it 

 is distinguished as rich. 



The second class of soils comprehends those which contain 

 from 30 to 50 per cent, of clay, and is denominated loamy. 

 These likewise are divided into two orders, the one with, the other 

 V, ithout lime ; and again into three species, according to the pro- 

 portion of vegetable mould present in them. 



The third class embraces those soils which contain not more 

 than 30 nor less than 20 per cent, of clay. They are called 

 sandy loams, and are subdivided into orders and species, on the 

 same principle as before. 



In the next, or fourth class, under the denomination of loamy 

 lands, are ranged those soils which contain from 10 to 20 per cent, 

 of clay : the remainder, with the exception of the small per centage 

 of limestone and hum.us they may contain, consisting of sand. 



The fifth class, designated as sandy, includes all those soils in 

 which the proportion of clay does not exceed 10 per cent.; and 

 here again the same subdivisions are adopted. 



Hitherto, the amount of calcareous matter present is not sup- 

 posed to exceed 5 per cent. ; but in the next class, that of marly 

 soils, the above ingredient ranges in a proportion varying from 

 5 to 20 per cent, of the whole. 



Marly soils are to be distinguished into five orders, of which 

 the first, called argillaceous, contains about 50 per cent, of clay ; 

 the second, loamy, from 30 to 50 ; the third, sandy-loamy, from 

 20 to 30; the fourth, loamy-sandy, from 10 to 20 ; and the fifth 

 is distinguished by the larger proportion of humus, which exceeds 

 in quantity 5 per cent, of the whole, and is therefore denoted as 

 humous marl ; which last is divided into three species — viz., 

 argillaceous, which contains above 50 per cent, of clay ; loamy, 

 which contains from 30 to 50 per cent. ; and sandy, possessing 

 from 20 to 30 per cent, of the same ingredient. 



We next arrive at that class of soils which contains more than 

 20 per cent, of carbonate of lime, and which is therefore distin- 

 guished as calcareous. These are subdivided according to the 

 proportion of clay they may contain : when this earth exists in 

 the proportion of more than 50 per cent., they are to be called 

 argillaceous ; when it is from 30 to 50, loamy; when from 20 to 

 SO, they are said to belong to the sandy loams of the calcareous 

 class; when from 10 to 20, to the loamy sands; and when either 

 destitute of clay altogether, or containing at most only 10 per 

 cent, of it, they are called sandy. 



