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lying above volcanic rocks, are absent here, inasmuch as this dis-
tinct locality did not favor their settlement.

There are in Maryland three totally different kinds of soil, viz :
Firstly, soils formed by the disintegration of volcanic rocks. These
soils, when they have gone through the process of washing, leave
as a body the remnants of Granite, Syenite, Mica-Slate, with
Garnets, &c., in a finer or coarser state of fraction.

Secondly, soils of mountainous regions, most especially with
those of the great coal region of Cumberland, and therefore formed
by the disintegration of gray Sandstone, red Sandstone, Limestone
and Clay Slates. Their body consists, therefore, of the remnants
of these rocks, which appear in them in various states of comminu-
tion. Thirdly and finally, we become acquainted with soils, which
owe their deposition and depths to rivers and streams of moun-
tainous regions, which, by their arrival in lower districts, have de-
posited again, in form of mould, fragments of the rocks of the
country through which they flowed.

The body of these soils is composed of all those ingredients,
which formerly were constituents of rocks, and which are now
present as single substances, almost entirely separated from each
other. When these soils have gone through a process of wash-
ing, nothing will therefore remain but sand, as it is in rivers: of
more or less perfectly round, finer or coarser grain, Peroxide of
Iron, Clay, Humus, Carbonate of Lime, &c.

After the foregoing remarks on the character of these soils in
general, as is due to their origin and the geological relations of
their locality in particular, let us now proceed to a contemplation
of their general treatment for the purpose of cultivating and im-
proving them in a proper and rational manner.

As to the soils under our first head; those which have been
formed by the slow disintegration of volcanic rocks, upon which
they directly lie; all of them are in general remarkable by their
small thickness and little binding power. This circumstance is
due to the large quantity of volcanic rocks present, which are
mixed only with a small quantity of alluvial matter, the product
of disintegration of the former. These rocks, in their undecom-
posed state, show as to their ratio as constituents of soil not the
least difference with that of common coarse sand; whilst in their
decomposed state, they are the source of an immense quantity of
those substances, which not only serve as a nourishment for plants,
but which also improve the soil materially in relation to its texture.
A glance into the chemical composition of the components of these
volcanic rocks, will show us at once in what manner a decompo-
sition of them will improve the texture of the soil.