AN IMPROVED METHOD OF OPERATING VENTILATING VALVES ESPECIALLY APPLICABLE TO TING GAS BURNERS
Year: 1859

page_text: LETTERS PATENT to James MacKenzie, Manager to William Strode,
of Saint Martin's-le-Grand, in the City of London, Gas Engineer, for the
Invention of "AN IMPROVED METHOD OF OPERATING VENTILATING VALVES,
Sealed the 26th July 1859, and dated the 29th January 1859.
PROVISIONAL SPECIFICATION left by the said James MacKenzie at the
Office of the Commissioners of Patents, with his Petition, on the 29th
January 1859.
I, JAMES MACKENZIE, Manager to William Strode, of Saint Martin's-le-
Grand, in the City of London, Gas Engineer, do hereby declare the nature of
the said Invention for "AN IMPROVED METHOD OF OPERATING VENTILATING VALVES,
ESPECIALLY APPLICABLE TO VENTILATING GAS BURNERS," to be as follows:-
In all ventilating gas burners there is an exit for the products of combustion
and vitiated air; when the burners are not alight, a downward current is liable
to enter the apartment in which the burner is placed, and produce cold currents.
Now, my Invention consists in the closing of the exit passage by means of a
valve opened by the pressure of the gas flowing to the burner, and closed upon
the pressure being withdrawn or cut off. My Invention will apply to the
working of ventilating valves in all apartments where gas is introduced.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James MacKenzie in the Great Seal Patent Office on
the 29th July 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
MACKENZIE, Manager to William Strode, of Saint Martin's-le-Grand, in the
City of London, Gas Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of January, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said James MacKenzie, Her special licence that I, the said James
MacKenzie, my executors, administrators, and assigns, or such others as I,
the said James MacKenzie, 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 "AN IM-
PROVED METHOD OF OPERATING VENTILATING VALVES, ESPECIALLY APPLICABLE TO
VENTILATING GAS BURNERS," upon the condition (amongst others) that I, the said
James MacKenzie, 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 James MacKenzie, 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 follow-
ing statement thereof, reference being had to the Drawings hereunto annexed,
that is to say:-
In all ventilating gas burners there is an exit for the products of combustion
and vitiated air; when the burners are not alight, a downward current is liable
to enter the apartment in which the burner is placed, and produce cold currents.
Now, my Invention consists in the closing of the exit passage, by means of a
valve opened by the pressure of the gas flowing to the burner, and closed upon 8
the pressure being withdrawn or cut off. My Invention will apply to the
working of ventilating valves in all apartments where gas is introduced.
Figure 1 of the accompanying Drawings is a side elevation, and Figure 2

page_text: is a horizontal section of an apparatus for operating ventilating valves in
ventilating gas burners constructed according to my Invention. The same
letters refer to like parts in both Figures. a is a pipe or shaft which may be
attached to a sun burner or any other ventilating gas apparatus; b is a valve
working in the ventilating shaft shewn closed by dotted lines at Figure 1; cis
a spindle on which the valve b turns; d, d, are levers attached at one end to
the spindle c, and at the other to connecting rods e, e, which are' slotted to
allow the levers d, d, to work in them. These connecting rods pass through
guides g and h, and have the upper vessels f,f, attached to them; i, i, are the
lower vessels, each of which is formed of two concentric cylinders, the space
between the two being filled with quicksilver or other fluid of a like nature:
The vessels ff. pass down between the concentric cylinders into the fluid, as
shewn; is a pipe for the admission of gas into the apparatus, which is in
communication with the supply pipe to the burners. When gas is turned on,
it flows through the pipe to the burners, and through the pipe j into the lower
vessels i, i; its pressure therein raises the upper vessels f, f, and with them the
rods e, e, whereby the valve bis opened to allow vitiated air, &c., to pass off
through the shaft a. When the gas is cut off, the upper vessels f.f, descend,
drawing the connecting rods e, e, with them, thereby closing the valve b,
whereby any downward current is prevented from entering the apartment
through the shaft a.
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I do not claim the employ-
ment of a valve for ventilating gas burners, or the arrangement of the vessels
floating in quicksilver; but what I do claim is, the employment of gas as a
motive
power for operating a ventilating valve, whether such ventilating valve
be placed in the chimney or shaft of a sun burner, or in any other kind of
ventilating shaft in chambers, apartments, or other places where gas .is
introduced.
In witness whereof, I, the said James MacKenzie, have hereunto set
my hand and seal, this Twenty-seventh day of July, One thousand
eight hundred and fifty-nine.
JAMES MACKENZIE. (L.S.)