The Value of Soil Anah/ses to the Farmer. 5 



example there was as 'much as 0*284 per cent., in another as 

 little as O'OZJ: per cent. In the soils from the Upper Greensand, 

 which are entirely distinct, we find very much the same range 

 of variation, 0'086 per cent, in the lowest case, 0-267 in the 

 highest. Our mechanical analysis, then, affords us a method 

 of classification which will bring the soils into natural groups, 

 and this the chemical analysis fails to do, though it will supple- 

 ment and sometimes check the grouping based upon mechanical 

 analysis. 



If next we compare the mechanical analysis of soils which 

 are used for the same purpose, though they may be in different 

 localities and of various origin, they again fall into natural types 

 of similar structure. To take an actual example from the south- 

 eastern counties, among the analyses were those of a number 

 of soils in different places on which fruit was grown success- 

 fully, others were known to be specially appropriate to potato 

 or barley growing. On comparing these results, it was found 

 that all the fruit soils, though of various origin, fell within the 

 limits of a fairly defined type ; the potato soils again constituted 

 another somewhat different type, as also did the barley soils. 

 Thus, we learn that the adaptability of a soil to a particular 

 crop is determined in the first place by its physical structure 

 as revealed by the process of mechanical analysis. Further, by 

 correlating from a large number of cases the mechanical com- 

 position and the crops which are known to answer on the soils, 

 we may thus work out a specification, as it were, of a wheat 

 soil, a barley soil, soil suitable for fruit or hops, &c., and 

 this specification is not a theoretical conclusion, but simply 

 a generalisation from actual experience. 



Of course, the mechanical analysis does not sum up all the 

 factors, we have also to take into account the rainfall, situation, 

 and other climatic considerations. For example, soils of a 

 particular type which grow first-rate barley in East Kent nearly 

 at sea level and with a rainfall of little more than 20 inches, 

 were found to be rarely cropped with barley in West Sussex, 

 where the elevation is greater, and the rainfall over 30 inches 

 per annum. 



We have now arrived at a position in which the soil 

 analyst can be of direct service to the farmer ; he can tell him 

 with some degree of confidence whether a particular crop can 

 be extended into a new district on soils hitherto untried. The 

 question does not of course arise with orclinary mixed 

 farming, because about that the enquirer can always learn 

 what has been done before on the land ; but suppose the 

 occupier desires to grow strawberries, or hops, or tobacco — 

 some expensive crop new to the locality — then the soil analyst 

 can tell him to what extent his soil agrees with other soils on 



