On the Chemical Properties of Soils. 
107 
The quantity of water runnlnj^ tlirougli the soil at sucli times, 
is amply sufficient completely to dissolve the soluble manuiinp^ 
matters. If it were, therefore, (juite correct that sandy soils had 
not in any degree the power of absorbing soluble manuring 
matters, they would be removed by the rain into the subsoil, 
neighbouring ditch, or drain, and could scarcely produce any 
effect u])on vegetation. 
Experience teaches us that the same kinds of manure produce 
very different practical results upon different soils. It must be ad- 
mitted that the composition of different soils varies considerably, 
and that this circumstance, no doubt, accounts to some extent for 
the variations in the practical results. 
There are, however, many apparently similar soils, that is to 
say, soils in which the analysis shows like quantities of the same 
constituents, such as potash, soda, lime, magnesia, phosphoric, 
sulphuric and silicic acid, and all the elements present in the 
ashes of plants, in which, notwithstanding, the same kind of 
manure produces a different practical result. This appears to 
me to indicate that tlie analysis of soils, as usually performed by 
chemists, does not afford in all cases a sufhcient guide to estimate 
their agricultural capabilities, nor to point out the kind of manure 
which is particularly well adapted for the special crop which we 
wish to raise. Even a detailed analysis of a soil gives only the 
proportions of the different soil-constituents, but generally without 
reference to the states of combination in which they exist in the 
soil ; and is altogether silent on the property possessed by all soils, 
in a higher or lower degree, of effecting striking and important 
changes in the manuring -matters which are placed upon the 
land. 
That this property belongs to every soil has been recently shown 
by me and others who have investigated this subject. It has 
likewise been shown that some soils possess the power of modify- 
ing the composition of manures much more thoroughly than others. 
It is, therefore, reasonable to connect the agricultural capabilities 
ot soils in a great measure with their power of retaining certain 
fertilizing matters with avidity, and of modifying others in a most 
interesting and unexpected manner. 
It is hardly necessary to dwell upon the importance of an 
accurate knowledge of the inherent capacity of soils to work up, 
so to speak, the crude fertilizing matters into new combinations ; 
to allow the free percolation of other — it may be less needful — 
substances, and to provide for a constant supply of food which 
is neither so soluble as to injure the produce, nor so insoluble 
as to remain inactive. 
The investigation of the exact circumstances under which these 
properties manifest themselves demands our serious and imme- 
