CONSTITUENTS OF SOILS. 



77 



of the plants with deep roots. The evil can 

 not be obviated by any methods sufficiently 

 economical for the farmer, because the soi 

 cannot be mixed with lime at a depth of five 

 or six feet. For many years experiment? 

 have been made in vain, in order to 

 this soil for sainfoin and lucerne, and much 

 expense incurred, which could all have been 

 saved, had the soil been previously analysed 

 This example affords a most convincing 

 proof of the importance of chemical know- 

 ledge to an agriculturist. 



15. Surface soil (A) of a sandy loam in 

 the vicinity of Brunswick, celebrated for its 

 beautiful crops of clover, rye, potatoes, anc 

 barley. The clover must, however, always 

 be manured with gypsum. (B) is an ana- 

 lysis of the subsoil at the depth of 1^ foot 

 100 parts contain: 



(A) (B) 



Silica with coarse siliceous sand 94 '274 95'146 



Alumina - - - - 1.560 1*416 

 Peroxide of iron with a little 



phosphoric acid - - - 2'496 2*528 



Peroxide of manganese - 0*240 0'320 



Lime CHOO 0*297 



Magnesia - : - 0'230 0'221 

 Potash and soda ... 0*102 0*060 

 Sulphuric acid - " ' .' 0'039 0'012 

 Chlorine .... Q'005 a trace 

 Humus soluble in alkaline car- 

 bonates - ... 0'444 

 Humus ; * . - - 0'210 



100-000 100-000 



The best property of this soil is, that its 

 inferior layers are nearly of the same com- 

 position as the superior, as far as the inor- 

 ganic constituents are concerned. It is a 

 soil upon which the plants mentioned above 

 will seldom fail ; and as it possesses a very 

 good mixture to the depth of four or five 

 feet, it would, doubtless, produce lucerne 

 also. 



16. Surface-soil (A) of a sandy loam in 

 the vicinity of Brunswick. It produces ex- 

 cellent crops of oats and clover, when the 

 latter is manured with gypsum. (B) Ana- 

 lysis of the subsoil taken from a depth of 1^ 

 foot. 100 parts contain: 



Silica and siliceous sand - 94 '4 30 



Alumina .... 1-474 

 Peroxide of iron with a little 



phosphoric acid - - 2*370 



Peroxide of manganese - a trace 



Lime, principally combined with 



silica .... 0*680 



Magnesia, idem - - 0*290 



Potash .... 0-190? 



Soda - - ... 0*0105 



Sulphuric acid - - . a trace 



Chlorine .... 0-015 



Humus - . 0*541 



(B) 



89*660 

 0*980 



7-616 

 a trace 



0*954 

 0*520 



0*150 



a trace 



a trace 



0*120 



100-000 100000 



Both the surface and the sub-soil contain 

 only traces of sulphuric acid. Hence the 

 ipplication of gypsum is attended with great 

 benefit. Without doubt, marl and lime would 

 be found of essential service. 

 17. Soil from the environs of Brunswick, I 



consisting principally of sand, and eminently 

 remarked for its sterility. It was, however, 

 much improved by manuring it with marl 

 which contained 24 per cent, of lime, to- 

 gether with magnesia, manganese, potash, 

 soda, gypsum, and common salt. 100 parts 

 of the soil contained : 



Silica and siliceous sand 

 Alumina - .... 

 Protoxide and peroxide of iron 

 Peroxide of manganese 

 Lime in combination with silica 

 Magnesia, idem ... 



Potash 



Soda - - 



Phosphoric acid combined with iron 

 Sulphuric acid .... 

 Chlorine - ... 



Humus ..... 



95-841 

 0-600 

 1-800 



a trace 

 0-038 

 0-006 

 0-002 

 0003 

 0*198 

 0-002 

 0-006 

 1*504 



100*000 



Here another proof is presented, that a 

 soil may be very rich in humus and yet be 

 very poor as regards fertility. By means of 

 the marl, the inorganic ingredients of the 

 plants are furnished to the soil, which con 

 tains them in very small quantity. 



18. The soil of a very fertile loam from 

 the vicinity of Walkenried. 100 parts con- 

 tain : 



Silica, with coarse-grained silicious sand 

 Alumina 



88-456 

 0-650 

 Peroxide and protoxide of iron, accompanied 



by much magnetic iron sand - - 5*608 

 Peroxide of manganese ... 0'560 



Carbonate of lime 1-063 



Carbonate of magnesia ... 1-68? 

 Potash combined with silica ... 0'04*> 

 Soda combined with silica - - 0-012 



Phosphate of lime .... 0'035 

 Sulphate of lime a trare 



Common salt 0-.<05 



Humus soluble in alkalies ... 55C 

 Humus with several azotised organic re- 



mains ..... 1-333 



100-000 



Gypsum acts most excellently upon this 

 land. The soils in the southern range of 

 the Harz mountains are particularly re- 

 marked for containing more magnesia than 

 lime. Even the different varieties of marl 

 contain a considerable quantity of magnesia. 

 Thus, in a specimen of marl obtained from 

 the vicinity of Walkenried, I obtained 55$ 

 per cent, carbonate of lime, and 30 pei 

 cent, carbonate of magnesia ; in another 41 

 per cent, lime, and 1 1 per cent, magnesia ; 

 and in a third, 47 per cent, lime, and 13} 

 per cent, magnesia. Most of these soils 

 contain also 1 per cent, of gypsum, 

 and 1 per cent, phosphate of lime, and 

 are, therefore, well fitted for manuring other 

 ands. 



19. Subsoil of a loam from a depth of 1$ 

 bot. It occurs in the vicinity of Brunswick. 

 The surface-soil is remarkable on account 

 )f producing beautiful red clover on being 

 manured with gypsum; although the so^l 

 tself contains only traces of lime, magnesia, 

 >otash, and phosphoric acid. 100 parts of 

 the subsoil contained : 



