188 
[Assembly 
In confirmation of this statement, I will quote the analysis of the 
ashes of several vegetables. 
Silica. Lime. Mumine, 
Wheat, 48 37 15 
Oats, 68 26 6 
Barley, 69 16 15 
Rye, 63 21 16 
Potatoes, 4 66 30 
Red clover, 37 33 30 
In addition to this I will quote farther the analysis of some of the 
most productive soils, which will serve as standards of comparison in 
estimating the value of any soil for agricultural purposes. The first 
was a good wheat soil, and contained, in one hundred parts. 
Coarse silex, 30 
Silica, 26 
Alumina, • 14 
Carb. lime, 30 
Another fertile soil furnished 
Silica, 77 to 79 
Alumina, 9 to 14 
Carb. lime, 5 to 12 
The most fertile soil formed artificially by the mixture of different 
earths, yield, on analysis. 
Coarse silex, 25 
Silica, 21 
Alumina, 16 
Carb. lime, 37 
Nothing of course is said of the quantity of water, or of vegetable 
and animal matter present in the soil, as the inquiry related solely to 
the earths essential to fertility. From these analyses it appears, that 
those earths enter directly into the vegetable economy, and are there- 
fore essential to the perfection of vegetable products. 
It does not appear from these or any experiments which have been 
made, that a soil must consist of certain elements in a definite or cer- 
tain given proportion, so far as they are necessary in the economy of 
vegetables, but only that they should exist in a sufficient proportion to 
supply the wants of vegetation. It is evident that where lime is in a 
small proportion it would be removed in the course of years entirely, 
