oking
candle is a bad burning one. There will be a guttering round about it
because of the irregularity of the stream of air and the badness of the
cup which is formed thereby. You may see some pretty examples (and I trust
you will notice these instances) of the action of the ascending current
when you have A little gutter run down the side of a candle, making it
thicker there than it is elsewhere. As the candle goes on burning, that
keeps its place and forms a little pillar sticking up by the side,
because, as it rises higher above the rest of the wax or fuel, the air
gets better round it, and it is more cooled and better able to resist the
action of the heat at a little distance. Now, the greatest mistakes and
faults with regard to candles, as in many other things, often bring with
them instruction which we should not receive if they had not occurred. We
come here to be philosophers; and I hope you will always remember that
whenever a result happens, especially if it be new, you should say, "What
is the cause? Why does it occur?" and you will in the course of time find
out the reason.

Then, there is another point about these candles which will answer a
question,--that is, as to the way in which this fluid gets out of the cup,
up the wick, and into the place of combustion. You know that the flames on
these burning wicks in candles made of beeswax, stearin, or spermaceti, do
not run down to the wax or other matter, and melt it all away, but keep to
their own right place. They are fenced off from the fluid below, and do
not encroach on the cup at the sides. I cannot imagine a more beautiful
example than the condition of adjustment under which a candle makes one
part subserve to the other to the very end of its action. A combustible
thing like that, burning away gradually, never being intruded upon by the
flame, is a very beautiful sight; especially when you come to learn what a
vigorous thing flame is--what power it has of destroying the wax itself
when it gets hold of it, and of disturbing its proper form if it come only
too near.

But how does the flame get hold of the fuel? There is a beautiful point
about that--_capillary attraction_[4]. "Capillary attraction!" you
say,--"the attraction of hairs." Well, never mind the name: it was given
in old times, before we had a good understanding of what the real power
was. It is by what is called capillary attraction that the fuel is
conveyed to the part where combustion goes