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a very large number of substances peculiar to different plants,
which substances make a difference between different classes.
Thus we have gum, sugar, starch, a great number of oils, such as
peppermint, turpentine, &c, a great variety of perfumes, and an
almost endless variety of substances used in medicine, such as
quinine, strychnine, &c, all composed of organic elements. A
great many substances have been discovered amongst organic
bodies composed of the same elements, and yet exhibiting physi-
cal and chemical properties essentially distinct from each other.
A great class of bodies known as the volatile oils, oil of turpen-
tine, essence of lemons, oil of balsam of copaiva, oil of rosemary,
oil of juniper, and many others, differing widely from each other in
their odor, in their medicinal effects, in their boiling point, contain
the same element—carbon and hydrogen—in the same proportion.
No one of them contains more of either element than the others
do. Nature, in her perfect laboratory, furnishing all these by skill-
ful arrangement and mode of union; now making food to support
life; now a deadly poison to destroy it; now a sweet perfume; now
a most fetid odor; now a brilliant dye. We have the same ele-
ments partially under our control, and though we cannot vie with
her in formative skill, yet we can, by calling the intellect to aid
the labor of the hands, make the earth to yield its fruits abun-
dantly, secure a sustenance for ourselves and a heritage for our
posterity.

THE ORIGIN AND MODE OF FORMATION OF THE

SOIL.

The soil is that portion of the earth which forms its outer crust,
and is indispensable to the vegetable world, as well to give it me-
chanical support as to furnish it materials for growth and nourish-
ment. It consists of the remnants or small particles of different
rocks, (inorganic matter,) intermingled with the remains of ani-
mals and plants, (organic matter.) A brief survey of the differ-
ent kinds of rocks; the multifarious mechanical and chemical in-
fluences to which they are exposed, the effects of which are de-
structive to their coherence—will show the manner of the forma-
tion of the soil, and disclose the general nature of its constituent
parts.

The various kinds of rocks which form the solid part of our
globe, are absolutely distinct from each other by their origin and
character, and naturally divide themselves into two principal class-
es, in various forms, viz: in Igneous forms, such as originate from,
the effects of fire, and are found in large bodies, without the least
regularity in the arrangement of their particles; and in Neptunic