74 



AGRICULTURAL CHEMISTRY. 



Sulphuric acid (in gypsum/ 

 Chlorine (in common salt) 

 Humus 



vA) (B) 



0-007 a trace 



O'OIO a trace 



0-846 0-226 



100-000 100-000 



This soil was much improved by manur- 

 ing with lime and ashes. It was then found 

 well fitted for clover, beans, and peas. 



4. Surface-soil (A) a loamy sand, from 

 the environs of Brunswick. (B) analysis 

 of the subsoil at the depth of 3 feet. 100 

 parts contain: 



100-000 100-000 



This soil produces luxuriant crops of lu- 

 cerne and sainfoin, as well as of all other 

 plants the roots of which penetrate deeply 

 into the ground. The reason is apparent. 

 The subsoil contains magnesia, which is 

 wanting in the surface-soil. 



5. Surface-soil (A) a loamy sand, from 

 the environs of Brunswick. (B) analysis 

 of the subsoil at a depth of 2 feet. 100 parts 

 contain : 



(A) 



Silica, with coarse siliceous sand 95'843 

 Alumina ".; - - ; 0'600 



Protoxide and peroxide of iron T800 

 Peroxide of manganese - a trace 



Lime, in combination with silica 0'038 

 Magnesia m do. do. 0'006 



Potash and soda ; :* - O'OOS 



Phosphate of iron - * 0'198 



Sulphuric acid ... 0'002 

 Chlorine - - . 0'006 



Humus soluble in alkalies - I'OOO 

 Humus insoluble hi alkalies 0*502 



(B) 



95.190 

 1-600 

 2-200 



a trace 

 0.455 

 0-160 

 0-004 

 0-400 



a trace 



o-ooi 



100-000 100-000 



This soil is characterised by its great 

 sterility. White clover could not be made 

 to grow upon it. The obvious cause of its 

 poverty is a deficiency of lime, magnesia, 

 potash, and gypsum; for we find that the 

 fertility of the soil was much increased by 

 manuring it with marl. The white clover, 

 which formerly had refused to grow on this 

 soil, now grew upon it with much luxuri- 

 ance. The aridity of the soil could not have 

 been the cause of its sterility, for the stiff 

 nature of the subsoil on which it rested pre- 

 vented a deficiency of moisture. 



6. Surface-soil (A) a loamy land from the 

 environs of Brunswick. (B) the analysis 

 of the subsoil, at a depth of 2 feet. 100 

 parts contain : 



Silica, with fine siliceous sand - 

 Alumina 



Protoxide and peroxide of iron 

 Peroxide of manganese 

 Lime, in combination with silica 

 Magnesia, idem 



Potash, idem 



Soda, idem 

 Phosphate of iron 

 Gypsum ... 

 Common salt - 

 Humus soluble in alkalies - 

 Humus accompanied by azotised 

 matter . . . 



Resinous matter 



(A) B) 



94-998 96.490 



0-610 T083 



1-080 1.472 



0.268 0-400 



0-141 0.182 



0-208 0-205 



0-050 0-070 



0-044 0-050 



0086 0-030 



0-041 0-005 



0-004 0-003 



0-400 0-010 



2.070 . . . 

 a trace . . . 



100.000 100.000 



This soil is by no means remarkable for 

 its sterility, but is decidedly improved by 

 manuring with burned ferruginous loam. 

 It is, however, rendered still better by the 

 use of burned marl a manure which is 

 rich in iron, potash, gypsum, and phosphate 

 of lime. The marl does not exert so favour- 

 able an action when applied in its natural 

 state; but the heat liberates the potash from 

 the insoluble compound which it forms with 

 silica. 



7. Surface-soil (A) a loamy sand, from 

 Brunswick. (B) analysis of the subsoil at 

 a depth of 1 feet. 100 parts contain : 



Silica, with fine siliceous sand 



Alumina - 



Protoxide and peroxide of iron 



Peroxide of manganese 



Lime, combined with silica 



Magnesia, idem <* \. 



Potash, idem * . ," * 



Soda, idem - ^ / ' .. - 



Phosphate of iron 



Sulphuric acid contained in gyp- 

 sum ... 



Chlorine - 



Humus soluble in alkalies - 



Humus, with azctised organic 

 remains 



(A) (B) 



92-980 96-414 



0-820 1-000 



1-666 1-370 



0.188 0-240 



0-748 0-364 



0-168 0-160 



0-065 0-045 



0-130 0082 



0-246 0-043 



a trace O'OOS 

 a trace 0'007 

 0-764 0270 



2-225 ' ' 

 100-000 100-000 



The soil when manured with gypsum is 

 very favourable to the production of legu- 

 minous plants and red clover. But it is 

 very remarkable, on account of the rust 

 which always attacks the corn plants which 

 may be grown upon it. This rust and mil- 

 dew (uredo linearis, puccinia grawiims) is a 

 disease which attacks the stem and leaves, 

 and is quite different from the brand (iiredo 

 glumarum) which appears on the seeds and 

 organs of reproduction. Rust is most fre- 

 quently detected on plants growing on soils 

 which contain bog-ore or turf-iron ore. Ac- 

 cording to Sprengel, rust contains phosphate 

 of iron, to which this chemist ascribes the 

 origin of the disease. It is very possible that 

 other causes may operate in the production 

 of similar diseases. 



8. Soil, a fine-grained loamy marl, from 

 the vicinity of Schoningen. It produces 

 corn, which is, however, very liable to 

 blight. 100 parts contain : 



