Let not the epithet "Perpetual," which the inventor applies to the
little apparatus that we are about to describe, frighten the reader,
for its only purpose is to indicate that the instrument in question is
capable of operating indefinitely, without care and without there ever
being any need of taking it apart.
[Illustration: Fig. 1--PERPETUAL GAS LIGHTER.]
In this gas lighter the inflammation is produced by a small spark,
but this latter, instead of being obtained by means of a pile, which,
after a certain length of time, has to be mounted anew or entirely
renewed, is secured by borrowing the energy produced by the operator
pressing upon a button. It is, then, in reality, a _mechanical_
lighter in which electricity intervenes as an intermedium charged
with the transformation of work into sufficient of a spark to produce
inflammation. Thanks to this principle, and to the arrangement of the
apparatus, there is secured cleanness, safety, and economy.
The lighting is reduced, then, to opening the cock and placing the
extremity of the rod over the burner, or over the edge of the glass
in burners provided with a chimney. Upon pressing the button and then
freeing it, a spark leaps between the two points and lights the gas.
(Fig. 1.)
[Illustration: Fig. 2.--A, cylinder with lighting rod, G. B, movable
cylinder fixed upon the axis, E. D, handle containing a rack actuated
by a button, F.]
The electric generator is a static induction machine of very small
size, and the arrangement of which will be understood by reference to
Fig. 1, which gives a general view of the apparatus with a portion
removed in order to show the relative position of the different parts,
and to Fig. 2, which shows the latter detached. A is an ebonite
cylinder containing the entire machine, and closed above by a cap of
the same substance upon which is screwed the lighting rod. The cap is
traversed by conducting wires which end in two contact springs that
establish an electric communication with the lighting tube.
Two inducting armatures of tin are cemented to the interior of
the cylinder, A, and occupy, each of them, about a third of its
circumference. The bottom of the cylinder, A, supports six contact
springs, parallel with each other and constituting three distinct pairs
which are properly connected, two by two, with the different parts of
the rest of the apparatus.
The movable or induced cylinder, B, of ebonite is provided with six
equidistant and insulated thin sheets of tin of a width nearly equal
to the interval which separates them. This cylinder is given a rapid
rotary motion by means of a system of rack and gearing every time the
button, F, is pressed. During the revolution of the cylinder the six
insulated plates come successively into communication with the six
springs, and these put them successively in communication, two by two,
first with the fixed inducting armatures, second, with the conductors
connected with the two points between which the spark is to pass, and,
third, with each other.
The apparatus operates, then, like Sir William Thomson's replenisher.
It is only necessary for the armatures upon the cylinder, A, to be at
the start at a difference of potential as small as desirable to suppose
it, in order to have the play of the machine multiply the charge and
soon give it sufficient tension to cross the interval that separates
the two points fixed at the extremity of the lighting rod, G. From a
technical point of view, the ingenious and new idea resides in the
application of a multiplier of charges with which the priming and
operation are always secured, provided the insulating parts are so dry
that the losses due to dampness are inferior to the machine's power of
production. This result, moreover, is easily attained by the use of a
hermetically closed system, and of drying substances placed in that
part of the cylinder which forms the handle of the apparatus.
From a mechanical point of view, the lighter contains a series of
practical and simple arrangements which make it an apparatus at once
convenient, strong, and sufficiently perpetual, as regards duration,
to partially justify the name that has been bestowed upon it by its
inventor, Mr. J. Ullmann.--_La Nature_.