ON THE USE OF LIME, MARL, AND SHELL-SAND. 37 



other soils from Wales and Cornwall were specially analysed 

 with reference to the present inquiry on the use of lime in agri- 

 culture. 



A very minute analysis, in which every constituent is ascer- 

 tained, however small its quantity, was considered to lead to no 

 useful result ; I therefore confined myself to the careful determi- 

 nation of the chief constituents of soils, and was thereby enabled 

 to examine a much larger number of soils than I could have 

 undertaken had each been submitted to a minute analysis. 



The soils upon which lime is used successfully in the West 

 are clay soils, peaty and marshy soils, and light sandy soils ; and 

 since the effect of lime is somewhat different upon each of these 

 three kinds of soils, I shall notice some particulars respecting the 

 use of lime upon each of these three classes of soils separately. 



On the Application of Lime on Clay Soils and the Composition of 

 Clay Land much benefited by Liming. 



There are many clay soils in Somersetshire and Devonshire 

 which are much benefited by the application of lime, since they 

 are greatly deficient in it. Thus all the clay soils in the districts 

 where the old red sandstone rocks prevail are much benefited by 

 liming ; indeed there are few stiff clay soils which will not be 

 greatly improved by the liberal use of lime. Thus on the stiff 

 clays near Honiton lime is very usefully employed ; and as soils 

 like those from Hembury Fort, near Honiton, of which an 

 analysis is appended, are naturally rich in all the mineral ele- 

 ments required by our cultivated crops, no fear need be enter- 

 tained that repeated dressings of lime will permanently injure 

 the land. 



Composition of two Stiff Clay Soils from Hembury Fort, near Honiton. 

 a. MECHANICAL ANALYSIS. 



No. 1. No. 2. 



Moisture .; 2.68 .. 3*34 



Organic matter and water of combination .. 5*22 ., 4*15 



Lime 2'42 .. 2'71 



Fine sand 32*55 .. 22'19 



Clay 57-13 .. 67'61 



100-00 100-00 



6. CHEMICAL ANALYSIS. 

 Moisture . 2'68 3'34 



Organic matter and water of combination . . 5*22 



Oxides of iron and alumina 7*61 



Carbonate of lime 2*42 



Magnesia and alkalies 1*74 



Insoluble silicious matter (chiefly clay) .. 80*33 



4-15 



11-52 



2-71 



1-36 



76-92 



100-00 100-00 



