he advantages which result from the study of this
science.

CAROLINE.

But, pray, tell us more precisely in what manner the discoveries of
chemists have proved so beneficial to society?

MRS. B.

That would be an injudicious anticipation; for you would not comprehend
the nature of such discoveries and useful applications, as well as you
will do hereafter. Without a due regard to method, we cannot expect to
make any progress in chemistry. I wish to direct your observations
chiefly to the chemical operations of Nature; but those of Art are
certainly of too high importance to pass unnoticed. We shall therefore
allow them also some share of our attention.

EMILY.

Well, then, let us now set to work regularly. I am very anxious to
begin.

MRS. B.

The object of chemistry is to obtain a knowledge of the intimate nature
of bodies, and of their mutual action on each other. You find therefore,
Caroline, that this is no narrow or confined science, which comprehends
every thing material within our sphere.

CAROLINE.

On the contrary, it must be inexhaustible; and I am a loss to conceive
how any proficiency can be made in a science whose objects are so
numerous.

MRS. B.

If every individual substance were formed of different materials, the
study of chemistry would, indeed, be endless; but you must observe that
the various bodies in nature are composed of certain elementary
principles, which are not very numerous.

CAROLINE.

Yes; I know that all bodies are composed of fire, air, earth, and water;
I learnt that many years ago.

MRS. B.

But you must now endeavour to forget it. I have already informed you
what a great change chemistry has undergone since it has become a
regular science. Within these thirty years especially, it has
experienced an entire revolution, and it is now proved, that neither
fire, air, earth, nor water, can be called elementary bodies. For an
elementary body is one that has never been decomposed, that is to say,
separated into other substances; and fire, air, earth, and water, are
all of them susceptible of decomposition.

EMILY.

I thought that decomposing a body was dividing it into its minutest
parts. And if so, I do not understand why an elementary substance is not
capable of being decomposed, as well as any other.

MRS. B.

You have misconceived the idea of _decomposition_; it is very different
from mere _division_. The latter simply reduces a body into parts, but
the form