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nia) which renders it extremely volatile, is more liable to loss
than any other of the manures commonly used; and that,
therefore, our particular attention should be directed to the
ways and means by which its full effect may be secured.

There is, in fact, but one substance which, if properly mixed
with this guano, will in every respect answer the purpose in
question, and this substance is soil itself. It has already
been remarked that water which has been saturated with
ammoniacal salts, if suffered to filter through soil, runs off
clear without the ammonia formerly contained in it, and that
this power of soils, of retaining the ammonia, has to be at-
tributed to the presence of portions of double silicates in
them. This power of soil comes here into action, and it is
plain in itself that its effect on the guano will be the more
thorough and full the more uniformly the guano has been
distributed throughout its mass. In order to attain this
object, it may be advisable to mix the guano, previous to its
application, with a suitable quantity of soil, (about double
its weight,) especially in the case when the quantity of Peru-
vian guano to be used is too small to allow its uniform dis-
tribution over the surface of the acre to be manured. The
soil best adapted for this purpose should be a loose, loamy
one, and rich in humus, so as to secure to it a specific gravity,
not exceeding that of the guano to be mixed with it; a per-
fect mixture of two substances being possible only when they
are of equal gravity, and only in this case they will not sep-
arate from each other when being sown.

The second point to which I shall direct the attention of
farmers, is to the quantity of guano which should be applied
per acre. My own practical observation, as well as that of
many others who followed my advice, has decided that it should
never go "beyond two hundred pounds, but may for many soils,
according to their degree of stiffness, fall short of one hundred
pounds, and this should always be applied with a drill.

There is further advice which I must give in relation to the
use of Peruvian Guano as to the crops to which it should be
applied; as a general rule it should be applied to the narrow
leaf plants, such as wheat, oats and rye, in the largest quanti-
ties. Plants absorb much of their ammonia from the air, the
smaller the leafy surface, the greater need is there conse-
quently for a larger supply of ammoniacal manures to plants
of this class, than to those which have a broad leafy surface,
such as tobacco, cabbage, corn, &c.

It has ever been my endeavor to diffuse amongst farmers
the true philosophy of farming, and to make them under-
stand that crops cannot profitably be increased by enormous