IMPROVEMENTS IN ApparatUS FOR EXTINGUISHING Fires
Year: 1875

page_text: LETTERS PATENT to Vonrose Hodson, of Burslem, in the County of
Stafford, Manufacturer of Aerated Waters, for the Invention of
“IMPROVEMENTS IN ApparatUS FOR EXTINGUISHING Fires.”
· IMPROVEMENts in ApparatUS FOR EXTINGUISHING FIRES.”
Sealed the 2nd June 1876, and dated the 7th December 1875.
PROVISIONAL SPECIFICATION left by the said Vonrose Hodson at
the Office of the Commissioners of Patents, with his Petition, on
the 7th December 1875.
I, VONROSE HODSON, of Burslem, in the County of Stafford, Manu-
facturer of Aerated Waters, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN APPARATUS FOR EXTINGUISHING FIRES," to
be as follows :-
The object of this Invention is to effect the automatic discharge of
carbonic acid or equivalent gas in places where fires have broken out,
and thereby to damp or extinguish such fires, and apprise the attendants
of what has occured. To this end I fit the building to which my
Invention is to be applied with an arrangement of pipes leading from a
:

page_text: gasometer in which the carbonic or other suitable gas is stored and
retained under pressure.
In each apartment of the building where a fire is liable to occur I
furnish the gas supply pipes with one or more discharge valves, which
are held to their seats by means of an ignitable composition forming a
solid packing above the valve. This packing may be made of a slow
burning powder, which as it is burned away will allow the valves to rise
from their seats under the pressure of the gas, and thereby open a
passage for the gas along the supply pipes, and its escape therefrom at
suitable orifices. Each valve box is fitted with a cap for containing the
inflammable packing that is used to hold down the valve to its seat, and
through an opening in the top of this cap the two platinum points
forming the terminals of the insulated wires from a battery are inserted
into the inflammable compound. One of these wires, instead of leading
directly from the battery, is broken, and its ends are inserted in a glass
tube containing mercury. The object of this arrangement is to ensure
that the electric circuit shall remain broken until the heat of the apart-
ment indicates the presence of fire. When this occurs the mercury will
rise by expansion and complete the metallic connection between the
ends of the severed wires. The circuit being now established the platinum
points will become heated (by the passage of electricity) and the destruc-
tion of the packing will take place. The supply valve being now released
it will be free to rise under the pressure of the gas, and open the way
for the discharge of the same into the apartment.
The supply pipes may be furnished with a whistle, which is to be
actuated by the gas, or the battery may be caused to set an alarum in
action for the purpose of drawing the attention of the watchman or
other attendant on the building to the action of the apparatus, who, so
soon as the fire is extinguished, must shut off the supply of gas.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of December, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said Vonrose Hodson, Her special
licence that I, the said Vonrose Hodson, my executors, administrators,
and assigns, or such others as I, the said Vonrose Hodson, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for " IMPROVEMENTS
IN APPARATUS FOR EXTINGUISHING FIRES," upon the condition (amongst
others) that I, the said Vonrose Hodson, my executors or administrators,
by an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed,
and cause the same to be filed in the Great Seal Patent Office within
six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Vonrose Hodson, do hereby declare
the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the Drawing hereunto
annexed, and to the letters and figures marked thereon (that is to
say) :-
:-
The object of this Invention is to effect the automatic discharge in
places where fires have broken out of carbonic acid or equivalent gas or
steam, and thereby to damp or extinguish such fires, and apprise the
attendants of what has occurred. To this end I fit the building to
which my Invention is to be applied with an arrangement of pipes
leading from a gasometer or reservoir, in which the carbonic or other
suitable gas is stored and retained under pressure, or with a boiler
containing steam.
In each apartment of the building where a fire is liable to occur I
furnish the gas or st am supply pipes with one or more discharge valves,
which are held to heir seats by means of an ignitable composition

page_text: L
·
forming a solid packing above the valve. This packing may be made of
a slow burning powder, which as it is burned away will allow the valves
to rise from their seats under the pressure of the gas, and thereby open
a passage for the gas or steam into the supply pipes, from whence it
will escape at suitable orifices and fill the apartment, and thereby extin-
guish the fire. Each valve box is fitted with a cap for containing the
inflammable packing that is used to hold down the valve to its seat, and
through an opening in the top of this cap a platinum wire forming part
of an electric circuit, and connected with suitable insulated copper or
other wires is inserted. The platinum wire is thus enclosed within the
inflammable compound in the cap, and is in close contact therewith.
One of the conducting wires, instead of leading directly from the battery
to the platinum wire enclosed in the inflammable compound, is divided
or broken, and its ends arc inscrted in a glass tube connected with a
bulb containing mercury. The object of this arrangement is to ensure
that the electric circuit shall remain broken until the temperature of
the apartment rises and indicates the presence of fire. When this
occurs the mercury will rise in the tube by expansion, and will complete
the metallic connection between the ends of the severed wires, thereby
completing the electric circuit. The circuit being now established the
platinum wire will become heated, in fact will be made red hot, by the
passage of the electricity, and the destruction of the packing will tako
place, as it will be slowly burnt away. The supply valve which has
confined the carbonic acid or steam being now released it will be free to
rise under the pressure of the gas, and will thus open the way for the
discharge of the gases or steam into the apartment, and will thereby
extinguish the fire therein.
The supply pipes may if desired be furnished with a whistle, which
may be actuated by the escaping gas or steam, or the battery may be
'caused to set an alarum in action for the purpose of drawing the atten-
tion of the watchman or other attendant in the building to the action of
the apparatus. As soon as the fire is extinguished the valve may be
'again closed as before. SO as to shut off the sunnly of are and

page_text: The short vertical pipe a is screwed into. or otherwise suitably con-
pected with a pipe communicating with a vessel or reservoir containing
carbonic acid or other analogous gas under pressure, or with a steam
boiler. The exit aperture of this pipe a is closed by a valve b, the
stem 6* of which extends upwards through a stuffing box c, and ter-
minates in a small chamber dat the top of the cap piece d. This small
chamber is charged with a slow burning combustible substance e, such
as a very slowly burning gunpowder, which will not explode, but which
when ignited will burn away, leaving the small chamber empty or nearly
so, the combustible matter having escaped therefrom in the form of gas
through small openings left for the purpose in the top, as shown in the
Figure. A small plugf (made of ivory or other suitable non-conductor of
electricity) is inserted in the top of the chamber d¹ for the purpose of
holding a loop of platinum wire 9, which forms part of the electric
circuit g, gg-from-the battery / below. The two outer ends of the
platinum wire are soldered or otherwise suitably connected with the
copper conducting wires g¹, g³, g³, one end of which is connected to the
battery h, and the other end to a wire in the thermometer tube i, the
bulb of which is connected by the wire g² with the other pole of the
battery . That end of the wire g² which is adapted to the bulb of the
thermometer is passed into the bulb, and is brought into metallic contact
with the mercury contained therein, so that the only break in the
metallic circuit will be in the bore of the tube. It will be evident
therefore that if the temperature of the apartment (in which the thermo-
meter is placed) be raised above a given degree, say, to from one
hundred and twenty degrees to one hundred and fifty degrees (as it
would be if a fire took place in the apartment) then the mercury in the
tube would rise and come into contact with that part of the circuit
wire g' which is introduced into the tube, and by this means the circuit
would be completed, and electricity would pass along the wire ' to the
platinum wire g within the small chamber d. The passage of the
electricity would, as has been already explained, make the platinum
wire red hot, and would thus ignite the combustible substance e, which
as it burns away would allow the valve b to yield to the pressure of the
gas or steam in the pipe a, and thereby allow the gas or steam to enter
the branch pipes j, j, and be delivered into the room in large volumes,
and thus extinguish the fire.
Having now described my Invention of "Improvements in Apparatus
for Extinguishing Fires," and having explained the manner of carrying

page_text: the same into effect, I claim as the Invention secured to me by Letters
Patent as aforesaid, the combination with the valve 6 for closing the
aperture communicating with the gas reservoir or steam boiler of a plug
composed of some suitable combustible substance, which is capable of
being ignited and converted into gas by the action of a current of
electricity, as herein set forth, so that when the combustible plug is
-burned away or converted into gas the valve stem will be allowed to rise
and permit the gas from the reservoir or steam from the boiler to pass
the valve and rush into the apartment and extinguish the fire as above
described.
In witness whereof, I, the said Vonrose Hodson, have hereunto set
my hand and seal, the Sixth day of June, in the year of of our
Lord One thousand eight hundred and seventy-six.