acts so as to raise the extinguisher, while the spiral approaches the
wick and lights it. It is well to actuate these extinguishing-lighters,
which may be located at a distance, not by a contact button, but by some
pulling arrangement, which is always much more easy to find in the dark
without much groping about. There might be used for such a purpose the
very motion of the front door, when opened, for lighting the hall; but
that would offer the inconvenience of operating likewise in the daytime,
and of thus needlessly using up the pile and the naphtha. In all these
spirit or naphtha lighters it is important that the spiral _shall not
touch_ the wick, but that it shall be placed a little above and on the
side, in the mixture of air and combustible vapor.

Several apparatus have likewise been devised for lighting gas by
electricity, and a few of these we shall describe.

The simplest form of these is Mr. Barbier's lighter for the use of
smokers, for lighting candles, sealing letters, etc. It consists of a
small gas-burner affixed to a round box, seven to eight centimeters in
diameter, and connected to the gas-pipe by a rubber tube. By maneuvering
the handle, the cock is opened and an electric contact set up of
sufficient duration to raise to a red heat the spiral, and to light the
gas. It is well in this case, for the sake of economizing in wire, to
utilize the lead gas-pipe as a return wire, especially if the pile is
located at some little distance from the lighter. In the arrangement
generally in use the key is provided with a special spring, which tends
to cause it to turn in such a way as to assume a vertical position, and
with a tooth, which, on engaging with a piece moving on a joint, holds
it in a horizontal position as soon as it has been brought thereto. In
order to extinguish the burner, it is only necessary to depress the
lever, and thus allow the key to assume again the vertical position,