A PRIZE ESSAY. 
13 
plant. A union so slow, that it gives out neither heat 
nor light. And yet it is in its results, the same as if 
fire had actually been seen and felt. Mould contains, 
then, a part of the carbon, oxygen, and hydrogen, or, 
if you like the terms better, mould of soil consists of 
the water and coal and salts of the plants. Mould is 
truly manure. If the mould of soil, as it has thus 
been defined, were separated from the earthy portions 
of soil, it would deprive that soil of the power of 
growing crops. Here, then, we come to a broad dis¬ 
tinction between soil and manure. The soil is the 
earth on which plants grow. The mould is the ma¬ 
nure of that soil. The soil is the earthy—the mould, 
that is, the carbon and salts, together with the ele¬ 
ments of water, are the vegetable part of arable land. 
But though the earthy part, the soil, as it is usually 
called, acts as a support, on which plants grow, it 
does not play a merely mechanical part. It has a 
distinct, decided, and important action upon the ma¬ 
nure. This action is chiefly chemical; and the fact 
that soils and manures do mutually affect the growing 
plant, is proved by the circumstance, that the first 
plants which grew derived their salts from the earth. 
MANURES—THEIR ACTION, ETC. 
But this chemical action of soil does not belong to 
the present discussion. We can understand what 
manures are, without deciding how they act. We can 
theorize and guess about the how of their action, when 
we have learned what they are. That is chiefly what 
the farmer wants to know. He wants to know what 
manure is, and what is likely to act as a manure. To 
these points, we shall confine our present remarks. 
Pointing out the great principles applicable to all 
manures, the nature of soils, and the manner in which 
they affect manures, must be left for another essay. 
The vegetable or manure part of soil alone, is now to 
be considered. Consider, now, reader, the great re- 
suits to which our analysis has led us; that a slow, 
