IMPROVEMENTS IN CARBURETTING OR NAPHTHALIZING GAS, AND IN THE APPARATUS EMPLOYED PROVISIONAL SPECIFICATION
Year: 1862

page_text: LETTERS PATENT to William Renwick Bowditch, Clerk, of Saint Andrews,
Wakefield, in the County of York, for the Invention of "IMPROVEMENTS
LETTERS PATENT to William Renwick Bowditch, Clerk, of Saint Andrews,
Wakefield, in the County of York, for the Invention of "IMPROVEMENTS
IN CARBURETTING OR NAPHTHALIZING GAS, AND IN THE APPARATUS EMPLOYED
PROVISIONAL SPECIFICATION left by the said William Renwick Bow-
ditch at the Office of the Commissioners of Patents, with his Petition,
on the 31st October 1862. .
I, WILLIAM RENWICK BOWDITCA, Clerk, of Saint Andrews, Wakefield,
in the County of York, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN CARBURETTING OR NAPHTHALIZING GAS, AND IN THE APPARATUS
EMPLOYED THEREIN," to be as follows:-
My Invention consists in applying heat to vaporize and keep vaporous the
hydrocarbons employed for carburetting or naphthalizing gas for illumination,
and in passing gas before it is burnt through or over the heated hydrocarbons.
The heat I prefer to use for this purpose is that produced by the same. gas
which is used with the vaporized hydrocarbons for illumination as this costs
nothing.
The apparatus I employ for the above purpose consists essentially of a gas-
tight vessel to hold the hydrocarbons, which vessel is connected by a pipe or
pipes with a burner or burners to consume the carburetted gas. The hydro-
carbon vessel is supplied through an aperture which is closed gas-tight except

page_text: during the filling. The carburetting apparatus is also connected by a pipe
with the pipes supplying gas, and is so arranged that heat produced by com-
bustion of the carburetted gas or otherwise is caused to act upon the hydro-
carbon vessel and also upon the pipe or pipes conveying the carburetted gas to
the burners, so that the gas and hydrocarbon vapours pass hot to the burners for
consumption. The amount of heat communicated by the burning gas to the
bydrocarbon vessel can be regulated by altering the distance between it and the
burning gas. By this process and apparatus I am able to use light-giving
materials such as naphthalin and the heavier coal oils which have hitherto been
comparatively worthless, and by their use to produce cheaply a very brilliant light.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Renwick Bowditch in the Great Seal Patent Office
on the 30th April 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
RENWICK BOWDITCH, of Saint Andrews, Wakefield, in the County of York,
Clerk, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of October, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-fifth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said William Renwick Bowditch, Her special license that I, the
said William Renwick Bowditch, my executors, administrators, and assigns,
or such others as I, the said William Renwick Bowditch, 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 CARBURETTING OR NAP-
THALIZING GAS AND IN THE APPARATUS EMPLOYED THEREIN," upon the condition
(amongst others) that I, the said William Renwick Bowditch, my executors
or administrators, by an instrument in writing under my, or his, 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.

page_text: NOW KNOW YE, that I, the said William Renwick Bowditch, 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, that is to say :-
My Invention consists in applying heat to vaporize and keep vaporous the
hydrocarbons employed for carburetting or napthalizing gas for illumina-
tion, and in passing gas before it is burnt through or over the heated hydro-
carbons, also in the heating the hydrocarbons, and keeping the volatile
products hot by the gas flame itself, and in improved apparatus to be used for
the above purposes.
To carry out my Invention I proceed as follows:-I take a gas-tight vessel -
such as that shown in the annexed Drawings, and marked G, or a vessel of
any other suitable form or size having an inlet and outlet pipe for the gas.
The inlet and outlet pipes are so placed that the gas in its passage through the
vessel, must pass over the surface of its contents. I call this the vaporizing
vessel. It is advantageous to bend the pipes inside the vaporizing vessel as
shown at H in the Drawings, in order to prevent the contents of the vessel
getting into the pipes while the apparatus is in use. The part bent over should
be from an inch and a half to two inches long, measured from Y to Z. The
vaporizing vessel has in its upper part an aperture shown.at O in the Drawings
about three-quarters of an inch diameter which can be closed gas-tight by a
screw plug or otherwise. Through this aperture the hydrocarbons are put
into the vaporizing vessel. This aperture is so placed that when the vessel is in
the position shown in the Drawings, and is as full as it can then be made, there
is a space of about half an inch between the apertures of the inlet and outlet
gas pipes and the surface of the hydrocarbon contained in the vessel. The inlet
pipe marked N in the Drawings outside the vessel may be of any form con-
venient. The outlet pipe which conveys the gas and vaporized hydrocarbons. to
the burner is bent as shown at I in the Drawings three or four inches above tho
burner so that a part of it as well as the vaporizing vessel itself may be heated
by the gas. This heating of the outlet pipe prevents condensation. The bending
of this. pipe is not always necessary, but is always preferable, as when a straight
pipe is used between the vaporizing vessel and the burner condensation of the
hydrocarbons sometimes occurs and puts out the light. When an argand
burner is used, this bend in the outlet pipe should be about three inches. above
the glass. The vaporizing vessel and pipes should be made of metal. I
prefer to have the vaporizing vessel made of iron with brazed joints. When
complete it may be tinned, galvanized, or enamelled externally to protect it
from rusting. To use my apparatus I attach the inlet pipe to a pipe which

page_text: supplies the gas about to be burnt, and place some hydocarbons in the
vaporising vessel and close the aperture gas-tight. Having supplied the
vaporizing vessel with hydrocarbons and securely. closed it, I turn on and
light the gas. The heat thus produced converts part of the hydrocarbons
into vapour. The passing gas carries this vapour from the vaporizing vessel
to the burner, where the gas and vapour are consumed together, the illuminating
power of the gas being thereby greatly increased. Any kind of illuminating com-
bustable gas may be used with this apparatus, but I prefer to use common coal
gas as generally used for purposes of illumination. Instead of employing the
heat produced by burning gas to vaporize the hydrocarbons used for carbu-
retting gas (as above described) any other convenient source of heat may be
used. Whatever be the source of heat it is necessary to have the vaporizing
vessel placed near the burner as. heavy hydrocarbons, condense easily and
obstruct the flow of gas. This is especially the case with napthalin. The
outlet pipe should always be kept as hot as the vaporizing vessel, and in all
cases I prefer to have this vessel and; part of the outlet pipe placed above
the burner. In this position it casts no shadow, and the heavy vapour, of
the hydrocarbons passes more easily and regularly to the burner. A greater
or less amount of illuminating power may be. obtained from.gas treated as
above, by heating the vaporizing vessel more or less as required. The amount
of heat may be increased by increasing the quantity of gas burnt, or by
diminishing the distance between the burner. and the vaporizing vessel, or
by both those means.combined. The amount of heat may be diminished by
diminishing the quantity of gas burnt, or by increasing the distance between
the burner and the vaporizing vessel, or by both these means combined.
The distance between the burner and the vaporizing vessel may be regulated
by means of a long thread upon the outlet pipe I as shown at K in the
Drawings, or by any other convenient means, and the quantity of gas may be
regulated by the tap. Instead of having a moveable burner, I prefer to use
.a fixed burner and to apply to the vaporizing vessel a false bottom which.can
be placed at any desired distance from the true bottom of the vessel, and
-between that bottom and the gas flame, or can be removed entirely. This
sufficiently regulates the heat applied, and gives no trouble. The false bottom
is best made of tin plate, and as shown at L on the Drawings, or it may be
of any form found convenient. When in use it may be supported by small
projections on the side of the vaporizing vessel as shown at M on the. Drawings
or in any other convenient manner. To reduce the quantity of hydrocarbons
vaporized in a given time, I remove the false bottom farther from the bottom
of the vaporizing vessel, and to increase the quantity of hydrocarbons so

page_text: vaporized, I place the false bottom nearer to the vessel or remove it altogether.
I find in practice that half an inch space between the vaporising vessel and
the false bottom answers well when a fish-tail or bat-wing burner is used and
the quantity of gas burnt is about three feet per hour, and the distance of
the burner from the vaporizing vessel is about eight inches. This description
of burner, quantity of gas, and distance from the vaporizing vessel to
the burner I recommend for general use. The vessel must be replen-
ished with hydrocrbons from time to time as required. For a single gas
light I prefer a vaporizing vessel of the capacity of about sixty cubic
inches. Where more than one burner is required to be supplied from one
vaporizing vessel the capacity of the vessel may be calculated on the basis of
thirty cubic inches additional for each additional light. The hydrocarbons
I prefer to use on account of their cheapness, safety, and easy use are those
obtained by the distillation of gas tar known as heavy naptha, "dead oil," and
'napthalin." Hydrocarbons which boil below two hundred and fifty degrees
Fahrenheit, are not so well adapted as these for use in my apparatus. They
are generally vaporized so rapidly as to supercharge the gas with their vapour
and thus to produce smoke in burning. I prefer in all cases to use hydrocarbons
which have about the same density as water, and to dissolve in them as much
napthalin as they will retain in solution at ordinary temperatures. The
bydrocarbons should be properly purified before use by any of the well
known methods. They afford a brilliant light when used crude, but then have
an offensive odour and yield injúrious products of combustion. Rock oils,
shale oils, rosin oils, camphines, and other hydrocarbons may be used in my
apparatus, but with less economy.
In witness whereof, I, the said William Renwick Bowditch, have here-
unto set my hand and seal, this Twenty-third day of April, in the year
of our Lord One thousand eight hundred and sixty-three.
30 Signed, sealed and delivered, by
the said William Renwick
Bowditch, in the presence of
PHIL. G. SKIPWORTH,
Solicitor, Wakefield.
W. R. BOWDITCH. (L.S.)