d by combustion--I must first of all tell you that
this water may exist in different conditions; and although you may now
be acquainted with all its forms, they still require us to give a little
attention to them for the present, so that we may perceive how the
water, whilst it goes through its protean changes, is entirely and
absolutely the same thing, whether it is produced from a candle, by
combustion, or from the rivers or ocean.

First of all, water, when at the coldest, is ice. Now, we speak of water
as water; whether it be in its solid, or liquid, or gaseous state, we
speak of it chemically as water.

We shall not in future be deceived, therefore, by any changes that are
produced in water. Water is the same everywhere, whether produced from
the ocean or from the flame of the candle. Where, then, is this water
which we get from a candle? It evidently comes, as to part of it, from
the candle; but is it within the candle beforehand? No! It is not in the
candle; and it is not in the air round about the candle, which is
necessary for its combustion. It is neither in one nor the other, but it
comes from their conjoint action, a part from the candle, a part from
the air. And this we have now to trace.

If we decompose water we can obtain from it a gas. This is hydrogen--a
body classed amongst those things in chemistry which we call elements,
because we can get nothing else out of them. A candle is not an
elementary body, because we can get carbon out of it; we can get this
hydrogen out of it, or at least out of the water which it supplies. And
this gas has been so named hydrogen because it is that element which, in
association with another, generates water.

Hydrogen gives rise to no substance that can become solid, either during
combustion or afterwards, as a product of its combustion. But when it
burns it produces water only; and if we take a cold glass and put it
over the flame, it becomes damp, and you have water produced immediately
in appreciable quantity, and nothing is produced by its combustion but
the same water which you have seen the flame of a candle produce. This
hydrogen is the only thing in Nature that furnishes water as the sole
product of combustion.

Water can be decomposed by electricity, and then we find that its other
constituent is the gas oxygen in which, as can easily be shown, a candle
or a lamp burns much more brilliantly than it does in air, but produces
the same products as when it burn