Indications of Fertility or Barrenness of Soils. 565 
Many also of the other kinds in our list are rendered fertile by 
manure, management, and draining, &c. Thousands of acres are 
at this moment, to all outward appearances, fertile, which are not 
permanently so, but which have been artificially made and kept 
so, and which, with the exception of land, the unproductive quality 
of which had been caused by a want of draining, will eventually, 
if neglected, return to a state of sterility. 
Indications of Fertility. 
All unmixed clay soils are too tenacious to be fertile; all 
unmixed silicious soils are too loose to be fertile ; and all unmixed 
chalk soil, that is a soil of carbonate of lime only, is too pure to 
be fertile. 
One would perhaps, without reflection, suppose, from those 
simple statements, that a mixture also of these three kinds of soils 
would not be fertile. We should be ready to suppose it impos- 
sible that good could arise out of a mixture of evils. But, how- 
ever paradoxical this may appear, it is, nevertheless, certain, 
that a mixture of the kind of soils named constitutes the 
medium through which the fertilizing properties contained in 
them are rendered active, which, in their unmixed state, would 
have remained dormant and useless. The mixture becomes a 
new soil, possessing new powers of absorbing and transmitting 
moisture ; and all that is necessary to give greater activity to its 
fertilizing powers is, to add a quantity of animal or vegetable 
matter, or of both, in a state of decomposition, if none be apparent 
in either, and afterwards to take care to return to this soil at least 
as much fertilizing matter as we have abstracted from it in our 
crops, in order to secure its permanent fertility. 
This will serve to show what an important feature consistency 
is, in fertile or barren soils, and what an easy thing it would be to 
make it available for the purpose of assisting the judgment, if it 
were uniform, or even if the consistency of fertile soils only were 
uniform. But unfortunately there are as many kinds of con- 
sistency as degrees of fertility, the limits being a sand, or soil the 
particles of which do not adhere except when wet, and a clay, 
which forms a paste when wet and something like a brick when 
dry. Between these two conditions fertility seems to oscillate, 
and can only be estimated between the highest and lowest point, 
by an assumption which is perfectly arbitrary, depending on the 
skill and judgment of the party employed to decide. 
Fertility and barrenness are but relative qualities, and, taken as 
we commonly use the terms, they are liable to vary with the ideas 
of individuals. It would be presumption in me to attempt to 
assign limits to, or give a precise definition of, either. I may 
venture an opinion, which may be reckoned as one amongst a 
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