IMPROVEMENTS IN GAS-LIGHT EXTINGUISHERS
Year: 1878

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake, &
Co., Patent Agents, Southampton Buildings, London, for the Invention of
"IMPROVEMENTS IN GAS-LIGHT EXTINGUISHERS." A communication from abroad
by William W. Gibbs, of Boston, Massachusetts, United States of America.
Sealed the 25th October 1879, and dated the 7th October 1878.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 7th October 1878.
13
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN GAS-LIGHT EXTINGUISHERS."
[A communication from abroad by William W. Gibbs, of Boston, Massachusetts,
United States of America.]
This Invention relates to devices for extinguishing gas lights by changing the
pressure of gas in the main pipe, and it comprises two inverted cups of different
sizes arranged upon a stem, one within the other, to operate corresponding cells
containing quicksilver, which cups are raised by a lever pivoted to an inclosing case
with an inlet passage extending from the gas pipe to the interior of one cup, and
an outlet passage extending from the interior of the other cup to the burner, the
cups being so weighted as to be held up in a position with one cup out of the
quicksilver, or dropped by a change of the gas pressure in the main pipe into a
position with both cups in the quicksilver.
In carrying the said Invention into practice two circular cells are provided in a
base, one being inside the other; there is also a central hole or aperture, the latter
communicating with the supply pipe, connected with the device at the upper part
of the case, and another orifice or passage in the top of the said base, extending
down the base and thence opening into the burner, so that gas from the supply pipe
below the burner must pass up through the base before reaching the burner. The
inner circular cell is made outside the said central hole and inside the said passage,
'Di 31

page_text: extending down the base to the burner, and the outer cell is made outside this
passage. The larger of the two said inverted cups is made of such length as that
its lower end may always remain in the quicksilver in the outer cell, the smaller
inverted cup being made considerably shorter than the other cup, say half as long.
Both the said cups are secured to a stem, the lower end of which extends a little
distance into the central hole, forming a guide to hold the stem centrally at the
lower end and the said cups concentric with their cells; and the said stem may be
made hollow at the top, with a screw turned down through the top of the case con-
taining the mechanism into the hole at the upper end of the stem, the said screw
serving as a guide to assist in keeping the stem in its vertical position.
The said case may be attached to the base by means of an ordinary bayonet joint,
or by any other convenient means, so that it may be easily removed when required.
Another cup is attached to the upper part of the stem, and a hole may be made
in the case immediately above this cup, which hole may be closed with a screw plug.
A lever is pivoted to the case at its inner end, being arranged to engage with the
said stem, which may be effected by making the inner end of the said lever forked,
the stem extending between the forks, with the cup just above the lever; or the end
of the lever may extend into a hole made in the stem, so that by drawing down the
outer end of the lever the stem and inverted cups may be raised. I however prefer
the first-named arrangement.
The operation of, the Invention is as follows:-Suppose the gas pressure in the
main pipe to be three inches while burning the lights, and it is desired to extinguish
all the lights in a street, or all the lights in all the streets in a city, by reducing the
gas pressure in the main pipe to two inches, the said screw plug is removed, and a
sufficient number of shot dropped into the cup on the upper part of the stem throughı
the hole, so that the stem and the inverted cups shall drop promptly when the gas
pressure in the main is reduced to two inches, but as long as the pressure remains
above two inches the weighted stem and inverted cups shall be held up. Quicksilver
is poured into both cells, and the lower end of the larger of the two inverted cups
is always in a position below the level of the quicksilver, and is immersed in the
quicksilver; but the lower end of the smaller inverted cups is only immersed in the
quicksilver in the inner cell when the stem and cups are held down by the weights
in the cup on the upper part of the stem, and is held above the quicksilver when
the stem is held up by the pressure of the gas. The latter flowing in from the
supply pipe through the said central hole or passage, is free to pass up into the space
inside the inner cup and out between the lower end of said cup, and the quicksilver
in its cell into the space inside the larger cup, and thence down through the passage
leading through the base to the burner where it is consumed at the tip.
When the gas pressure in the above example is at three inches in the main, such
pressure is not sufficient to raise the stem and cups, owing to the small area of its
pressure in the smaller inverted cup, but when the stem and cups are raised and the
gas is admitted into the larger inverted cup, the area of gas pressure is so largely
increased that it is quite sufficient to overcome the weight above, and the cups are
held in their elevated position until the gas pressure in the main is reduced to two
inches, the point to which it was adjusted, when the weighted stem, instantly
dropping the lower end of the larger cup, is immersed in the quicksilver in the inner
cell, and the flow of gas through from the central passage to the passage leading to
the burner is instantly and completely shut off, and the lights extinguished.
Different lamp posts in the different streets of a city provided with this device
may be extinguished at different times by adjusting the weights to different
pressures; for example, suppose the gas pressure in the main to bo four inches, the
lights in one street could be adjusted to be extinguished by reducing the pressure
a half inch, those in another street to be extinguished by a reduction of one inch in
pressure; while still another set by a reduction of an inch and a half. By these
respective reductions in pressure at different times the lights will be extinguished
at different times in as many sets.

page_text: It is evident that instead of the cup on the upper part of the stein, the latter may
be weighted by placing small discs thereon until it is suitably balanced or adjusted
to the desired pressure, when it would operate in precisely the same manner as above
described.
And it is also evident that the stem may be made to sustain the burner without
departing from the principle of my Invention.
It is also obvious that instead of the said lever I may extend the stem up through
the top of the case to guide it, and out at the side of the case, so that instead of
pulling down the outer end of the lever I might raise the cups by pushing up the
extension upon the stem, and thus dispense with the lever, and accomplish the same
result of admitting the gas to the burner.

page_text: The operation of this improved gas-light extinguisher is as follows, that is to
say-Supposing the gas pressure in the main pipe to be three inches while burning
the lights, and it is desired to extinguish all the lights in a street, or all the lights
in all the streets in a city, by reducing the gas pressure in the main pipe to two
inches. For this purpose the small plug g is removed, and a sufficient number of
shots dropped into the cup h through the hole, so that the stem and inverted cups
c and e¹ will drop immediately the gas pressure in the main is reduced to two inches ;
but as long as the pressure remains above two inches the weighted stem and inverted
cups will be held up by such pressure. Quicksilver is poured into both cells c and e
to about the height represented by the line H, and the lower end of the larger
cup c' will always be in a position below this level and immersed in the quicksilver;
but the lower end of the smaller cup e¹ is only immersed in the quicksilver in the
coll e when the pressure in the main is reduced and the stem and cups are pressed
down by the shots or weights in the cup h, the said cup e¹ being raised above the
quicksilver when the stem is held up by the pressure of the gas. The gas then
flowing in from the supply pipe through the central hole or passage o, is free to pass
up into the space inside the inner cup e¹, and out between the lower end of said
cup and the quicksilver in its cell into the space inside the larger cup, and thence
down through the passage n into the burner, where it is consumed at the tip in the
ordinary manner.
When the gas pressure in the main, as in the above example, is at three inches,
such pressure is not sufficient to raise the stem and cups, owing to the small area of
its pressure in the smaller cup e¹, but when the stem and cups are raised and the
gas is admitted into the larger cup c', the area of gas pressure is so largely increased
that it is quite sufficient to overcome the weight above, and the cups are held in
their elevated position until the gas pressure in the main is reduced to two inches,
the pressure to which the said weights are adjusted, when the weighted stem
instantly dropping the lower end of the cup e' is immersed in the quicksilver in the
cell e, and the flow of gas from the passage o to the passage n is instantly and com-
pletely shut off, and the lights extinguished.
Different lamp posts in the different streets of a city provided with this device
may be extinguished at different times by adjusting the weights to different
pressures; for example, suppose the gas pressure in the main to be four inches, the
lights in one street could be adjusted to be extinguished by reducing the pressure
one half an inch, those in another street to be extinguished by a reduction of one
inch in pressure, while still another set by a reduction of one inch and a half. By
these respective reductions in pressure at different times the lights will be extin-
guished at different times in as many sets.
It is evident that instead of the cup h on the stem a the latter may be weighted
by placing small discs thereon until it is suitably balanced or adjusted to the
desired pressure, when it would operate in precisely the same manner as above
described.
And it is also evident that the stem a may be made to sustain the burner B
without departing from the principle of my Invention.
It is also obvious that instead of the lever f I may extend the stem up through
the top of the case to guide it, and out at the side of the case, so that instead of
pulling down the outer end of the lever f I might raise the cups by pushing up the
extension upon the stem, and thus dispense with the lever, and accomplish the same
result of admitting the gas to the burner.
Having thus fully described the said Invention, as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it under-
stood that I claim,-
First. A gas-light extinguisher consisting of a base provided with cells arranged
to contain quicksilver or other scaling fluid, and with passages, the base so formed
being combined with inverted cups, a stem arranged to be suitably weighted, and a
lever, all as above described.

page_text: Second. In a gas-light extinguisher, the base provided with cells and with
passages in combination with the inverted cups and the stem arranged to be
weighted and adapted to be raised by a force applied outside the case, as above
specified.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twenty-ninth day of March, in the year of our Lord One
thousand eight hundred and seventy-nine.
W”. KOB™. LAKE. (L.S.)