210 



ments, and suitable compensation must be given, or it will become bar- 

 ren — plants cannot live in it. Iq this juncture the agricultural chem- 

 ist steps in most opportunely, and explains to us the composition of 

 plants, analyses soils, and enables us to select the particular kind of ma- 

 nure which is best suited to the crop we are about to raise. 



By experiments made at Bechelbronn in France, M. BoussingauU 

 ascertained that an average crop of wheat, weighed per acre, as follows: 



as stored. dried. ash. 



Grain 1500 1285 33 



Straw, 3400 2550 178 



These ashes being analysed wore found to consist of: 



grain ash. straw ash. 



Phosphoric acid, 15.61 .52 



Sulphuric acid, 33 1.78 



Carbonic acid, 



Chlorine, traces. 1.07 



Lime, .-. 0.96 15.13 



Magnesia, 5.25 8.90 



Potash, 9.73 16.37 



Soda, traces. .53 



Silica, 43 120.53 



Alumina, 1.78 



Moisture and loss, 0.79 6.59 



33 178.00 



We are told by Liebig and several other chemists, that the mineral 

 ingredients found in the ashes of plants, represent the food which the 

 plants have consumed ; these substances are in fact the inorganic ele- 

 ments which they have extracted from the soil, and which cannot be 

 consumed by fire. 



100 parts of the ashes of the various plants mentioned in the follow- 

 ing table, contain the specified amount of mineral ingredients: 



Wheat. W. straw. Oats. O. straw. Po!atoes. Turnips. Cloror. 



Phosphoric acid, 47.0 3.1 14.9 3.0 11.3 6.1 6.3 



Sulp. acid, 1. 1. 1. 4,1 7.1 10.9 2.5 



Carbonic acid, 1.7 3.3 13.4 14.0 25.0 



Chlorine, traces 0.6 0.5 4.7 2.7 2.9 2.6 



