But is it possible to burn diamond?

MRS. B.

Yes, it is; and in order to effect this combustion, nothing more is required than to apply a sufficient degree of heat by means of the blow-pipe, and of a stream of oxygen gas. Indeed it is by burning diamond that its chemical nature has been ascertained. It has long been known as a combustible substance, but it is within these few years only that the product of its combustion has been proved to be pure carbonic acid. This remarkable discovery is due to Mr. Tennant.

Now let us try to make some carbonic acid.—Will you, Emily, decant some oxygen gas from this large jar into the receiver in which we are to burn the carbon; and I shall introduce this small piece of charcoal, with a little lighted tinder, which will be necessary to give the first impulse to the combustion.

EMILY.

I cannot conceive how so small a piece of tinder, and that but just lighted, can raise the temperature of the carbon sufficiently to set fire to it; for it can produce scarcely any sensible heat, and it hardly touches the carbon.

MRS. B.

The tinder thus kindled has only heat enough to begin its own combustion, which, however, soon becomes so rapid in the oxygen gas, as to raise the temperature of the charcoal sufficiently for this to burn likewise, as you see is now the case.

EMILY.

I am surprised that the combustion of carbon is not more brilliant; it does not give out near so much light or caloric as phosphorus, or sulphur. Yet since it combines with so much oxygen, why is not a proportional quantity of light and heat disengaged from the decomposition of the oxygen gas, and the union of its electricity with that of the charcoal?