cubic foot of water and a cubic foot of hydrogen.

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 the candle produce. It is
important to remember that this hydrogen is the only thing in nature which
furnishes water as the sole product of combustion.

And now we must endeavour to find some additional proof of the general
character and composition of water; and for this purpose I will keep you a
little longer, so that at our next meeting we may be better prepared for
the subject. We have the power of arranging the zinc which you have seen
acting upon the water by the assistance of an acid, in such a manner as to
cause all the power to be evolved in the place where we require it I have
behind me a voltaic pile, and I am just about to shew you, at the end of
this lecture, its character and power, that you may see what we shall have
to deal with when next we meet. I hold here the extremities of the wires
which transport the power from behind me, and which I shall cause to act
on the water.

We have previously seen what a power of combustion is possessed by the
potassium, or the zinc, or the iron-filings; but none of them shew such
energy as this. [The Lecturer here made contact between the two terminal
wires of the battery, when a brilliant flash of light was produced.] This
light is, in fact, produced by a forty-zinc power of burning: it is a
power that I can carry about in my hands, through these wires, at
pleasure--although, if I applied it wrongly to myself, it would destroy me