CLAr AND SAND. — SPECIAL MIXTURES. 



325 



to a more rapid increase in the general produce of the British soil is the 

 practical difficulty which exists in convincing the owners and occupiers 

 (}f the soil that such is the case, or would be the case, in regard to their 

 own holdings. The more widely a knowledge of the entire subject, in 

 all its bearings, becomes diffused, the less it is to be hoped will this diffi- 

 culty become — for the economist, who regards the question of improve- 

 ment as a mere matter of profit and loss, cannot strike a fair balance 

 unless he knows the several items he may prudently introduce into each 

 side of his account. 



Thus in reference to the special point now before us, it seems re.ason- 

 able to believe that, in a country such as that here represented, where 

 alternate hilU of sand (3), and hollows, and flats of clay (4) occur, there 



^^^g^s^;^^^ 



may be many spots where both kinds of soil — being near each other- 

 might be improved by mutual admixture, at a cost of labour which the 

 alteration in the quality of the land might be well expected to repay. 

 In this condiiion i« a considerable portion of the eastern half of the 

 county of Durham, and, especially, I may mention the neighbourhood 

 of Castle Eden, where a cold, stiff, at present often poor clay, rests upon 

 red, rich-looking, loamy sand, in many places easily accessible, and by 

 admixture with which its agricultural capabilities may be expected to 

 improve. In this locality, and in many others besides, those having a 

 pecuniary interest in the land rest satisfied that their fields are incapable 

 of such improvement, or would gk^ no adequate return for the outlay 

 required, without troubling themselves to collect and compare all the 

 facts from which a true solution of the question can alone be drawn. 



Besides such general admixtures for the improvement of land, the 

 geological formation of certain districts places within the reach of its in- 

 ielligent farmers means of improvement of a special kind, of which they 

 may often profitably avail themselves. Thus both in Europe and Ame- 

 rica, the green-sand soils (p. 243) are found to be very fertile, and 

 the sandy portions of this formation are often within easy distance of the 

 stiff-clays of the gault, and of the poor soils of the chalk with either of 

 which they might be mixed with most beneficial effects. The soils that 

 rest on the new, and even on some parts of the old red sandstone, are 

 in like manner often within an available distance of beds of red marl of 

 a very fertilizing character (p. 248), while in the granitic and trap 

 districts the materials of which these rocks consist, if mixed with judg- 

 ment, maybe made materially to benefit some of the neighbouring soils. 

 To this point, however, I shall draw your attention again in my next lec- 

 ture, when treating of mineral manures. 



