The Chemical History of a Candle | Page 2

on former occasions--and, if you please, I shall
do so again. And though I stand here with the knowledge of having the
words I utter given to the world, yet that shall not deter me from
speaking in the same familiar way to those whom I esteem nearest to
me on this occasion.
And now, my boys and girls, I must first tell you of what candles are
made. Some are great curiosities. I have here some bits of timber,
branches of trees particularly famous for their burning. And here you
see a piece of that very curious substance taken out of some of the bogs
in Ireland, called _candle-wood_,--a hard, strong, excellent wood,
evidently fitted for good work as a resister of force, and yet withal
burning so well that where it is found they make splinters of it, and
torches, since it burns like a candle, and gives a very good light indeed.
And in this wood we have one of the most beautiful illustrations of the
general nature of a candle that I can possibly give. The fuel provided,
the means of bringing that fuel to the place of chemical action, the
regular and gradual supply of air to that place of action--heat and
light--all produced by a little piece of wood of this kind, forming, in
fact, a natural candle.
But we must speak of candles as they are in commerce. Here are a
couple of candles commonly called dips. They are made of lengths of
cotton cut off, hung up by a loop, dipped into melted tallow, taken out
again and cooled, then re-dipped until there is an accumulation of
tallow round the cotton. In order that you may have an idea of the
various characters of these candles, you see these which I hold in my
hand--they are very small, and very curious. They are, or were, the

candles used by the miners in coal mines. In olden times the miner had
to find his own candles; and it was supposed that a small candle would
not so soon set fire to the fire-damp in the coal mines as a large one;
and for that reason, as well as for economy's sake, he had candles made
of this sort--20, 30, 40, or 60 to the pound. They have been replaced
since then by the steel-mill, and then by the Davy-lamp, and other
safety-lamps of various kinds. I have here a candle that was taken out
of the _Royal George_[1], it is said, by Colonel Pasley. It has been
sunk in the sea for many years, subject to the action of salt water. It
shews you how well candles may be preserved; for though it is cracked
about and broken a good deal, yet, when lighted, it goes on burning
regularly, and the tallow resumes its natural condition as soon as it is
fused.
Mr. Field, of Lambeth, has supplied me abundantly with beautiful
illustrations of the candle and its materials. I shall therefore now refer
to them. And, first, there is the suet--the fat of the ox--Russian tallow, I
believe, employed in the manufacture of these dips, which Gay Lussac,
or some one who entrusted him with his knowledge, converted into that
beautiful substance, stearin, which you see lying beside it. A candle,
you know, is not now a greasy thing like an ordinary tallow candle, but
a clean thing, and you may almost scrape off and pulverise the drops
which fall from it without soiling anything. This is the process he
adopted[2]:--The fat or tallow is first boiled with quick-lime, and made
into a soap, and then the soap is decomposed by sulphuric acid, which
takes away the lime, and leaves the fat re-arranged as stearic acid,
whilst a quantity of glycerin is produced at the same time.
Glycerin--absolutely a sugar, or a substance similar to sugar--comes out
of the tallow in this chemical change. The oil is then pressed out of it;
and you see here this series of pressed cakes, shewing how beautifully
the impurities are carried out by the oily part as the pressure goes on
increasing, and at last you have left that substance which is melted, and
cast into candles as here represented. The candle I have in my hand is a
stearin candle, made of stearin from tallow in the way I have told you.
Then here is a sperm candle, which comes from the purified oil of the
spermaceti whale. Here also are yellow bees-wax and refined bees-wax,
from which candles are made. Here, too, is that curious substance

called paraffin, and some paraffin candles made of paraffin obtained
from the bogs of Ireland. I have here also a substance brought from
Japan, since we have forced an entrance into that out-of-the-way
place--a sort of wax which a