ANALYSIS OF SOILS. 233 



One hundred parts by weight of the soil left, after ignition, only 

 fifty parts. One hundred parts of these ashes consisted of 



Silica and silicious sand, 95.204 



Alumina, 1.640 



Peroxide of iron, 1.344 



Peroxide of manganese, 0.080 



Lime in combination with sulphuric acid, . . . 0.544 



Magnesia combined with silica, 0.465 



Potash and soda, 0.052 



Phosphoric acid, (principally as phosphate of iron,) 0.330 



Sulphuric acid, 0.322 



Chlorine, 0.019 



100.000 



&quot; By comparing this analysis with the one which has preceded 

 it, an increase in certain of the constituents is observed, partic 

 ularly with respect to the sulphuric acid, potash, soda, magnesia, 

 oxide of iron, manganese, and alumina. From this it follows, 

 that the humus, or, in other words, the vegetable remains, must 

 have contained a quantity of these substances confined within it 

 in such a manner that they were not exhibited by analysis.&quot; 



Here it seems, then, admitted, that the most minute chemical 

 analysis, even to hundred thousandths, failed to detect all the 

 latent elements of which the soil was composed. 



&quot; Oats and barley were sown on this land the second year 

 after being reclaimed, and both suffered much from rust, although 

 different parts of the soil were manured with marl, lime, and 

 peat-ashes, whilst other portions were left without manure. In 

 the first year, all the different parts of the field produced pota 

 toes ; but they succeeded best in those parts which had been 

 manured with peat-ashes, lime, and marl. In the second year, 

 oats, mixed with a little barley, were sown upon the soil ; and 

 the straw was found to be strongest on the parts treated with 

 peat-ashes, lime, and marl.&quot; [I have never known this to fail to 

 be the case on any soil.] &quot; Red clover was sown in the third 

 year ; and it appeared in best condition on those portions of the 

 soil manured with marl and lime. Upon the divisions of the 

 field which had been left without manure, as well as on those 

 20* 



