conveniently do without. You now see the charcoal burning, but not as a
flame (or if there be a flame, it is the smallest possible one, which I
know the cause of--namely, the formation of a little carbonic oxide close
upon the surface of the carbon). It goes on burning, you see, slowly
producing carbonic acid by the union of this carbon or charcoal (they are
equivalent terms) with the oxygen. I have here another piece of charcoal,
a piece of bark, which has the quality of being blown to pieces--exploding
as it burns. By the effect of the heat, we shall reduce the lump of carbon
into particles that will fly off; still every particle, equally with the
whole mass, burns in this peculiar way: it burns as a coal, and not like a
flame. You observe a multitude of little combustions going on, but no
flame. I do not know a finer experiment than this, to shew that carbon
burns with a spark.

Here, then, is carbonic acid formed from its elements. It is produced at
once; and if we examined it by lime-water, you will see that we have the
same substance which I have previously described to you. By putting
together 6 parts of carbon by weight (whether it comes from the flame of a
candle or from powdered charcoal) and 16 parts of oxygen by weight, we
have 22 parts of carbonic acid; and, as we saw last time, the 22 parts of
carbonic acid, combined with 28 parts of lime, produced common carbonate
of lime. If you were to examine an oyster-shell, and weigh the component
parts, you would find that every 50 parts would give 6 of carbon and 16 of
oxygen, combined with 28 of lime. However, I do not want to trouble you
with these minuti¾--it is only the general philosophy of the matter that
we can now go into. See how finely the carbon is dissolving away [pointing
to the lump of charcoal burning quietly in the jar of oxygen]. You may say
that the charcoal is actually dissolving in the air round about; and if
that were perfectly pure charcoal, which we can easily prepare, there
would be no residue whatever. When we have a perfectly cleansed and