A NEW METHOD OF AND APPARATUS FOR INDICATING THE ILLUMINATING POWER OF GAS
Year: 1881

page_text: LETTERS PATENT to Thomas Thorp, of Whitefield, in the County of Lancaster,
Architect, and Robert Tasker, of Prestwich, in the same County, for an
Invention of "A NEW METHOD OF AND APPARATUS FOR INDICATING THE
ILLUMINATING POWER OF GAS."
PROVISIONAL SPECIFICATION left by the said Thomas Thorp and
Robert Tasker at the Office of the Commissioners of Patents on the
26th February 1881.
THOMAS THORP, of Whitefield, in the County of Lancaster, Architect, and
ROBERT TASKER, of Prestwich, in the same County. "A NEW METHOD OF AND
APPARATUS FOR INDICATING THE ILLUMINATING POWER OF GAS."
In performing our Invention we make use of a tube of metal or other material
in the interior of the upper part of which is an inverted trunicated cone; in the
lower end is inserted and secured hermetically a glass tube, part of which glass
tube is exposed to view by a portion of the metallic tube being cut away, the lower
part of the main tube to be connected with gas supply. We use a rod of glass,
wire, or other suitable material with discs of ebonite or other material secured at
each end, one disc moving in the aforesaid conical metal tube, and the other moving
in the glass tube and serving as a pointer.
We attach a metallic or other index plate to the said metallic tube, and lying
upon and parallel to the glass tube, which index plate is engraved or otherwise
marked as required. We use an improved argand burner and chimney, the burner
having annular discs of gauze or other materials immediately under the external
orifices, from which the gas issues to be consumed, the chimney having an annular
metal or other diaphragm secured at the top; the argand burner to be secured to
the upper part of the metal tube by a metal or other coupling.
By the above described apparatus we are enabled to indicate instantaneously
and accurately the illuminating power of gas.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas Thorp and Robert Tasker in the Great Seal Patent
Office on the 23rd August 1881.
THOMAS THORP, of Whitefield, in the County of Lancaster, Architect, and
ROBERT TASKER, of Prestwich, in the same County. "A NEW METHOD OF AND
APPARATUS FOR INDICATING THE ILLUMINATING POWER OF GAS."
In performing our Invention we make use of a tube of metal or other material
in the interior of the upper part of which is an inverted truncated cone; in the
lower end is inserted and secured hermetically or otherwise a glass tube, part of
which glass tube is exposed to view by a portion of the metallic tube being cut
away, the lower part of the main tube to be connected with gas supply. We use
a rod of glass, wire, or other suitable material with discs of ebonite or other
material secured at each end, one disc moving in the aforesaid conical metal tube
and the other moving in the glass tube and serving as a pointer. We attach a
metallic or other index plate to the said metallic tube, and lying upon and parallel
to the glass tube, which index plate is engraved or otherwise marked as required.
We use an improved argand burner and chimney, the burner having annular discs
of gauze or other material immediately under the external orifices, from which the
gas issues to be consumed; the gauze or other material through which the gas
passes causes it to burn with a steady even flame; the chimney has an annular
metal or other diaphragm secured at the top to regulate and steady the flame.
The argand burner is secured to the upper part of the metal tube by a metal or
other coupling. We also use a jet burner in place of an argand burner when
desired. By the above described apparatus we are enabled to indicate instanta-
neously and accurately the illuminating power of gas. And in order that our
Invention may be fully understood and readily carried into effect, we will describe
the accompanying Sheet of Drawings, reference being had to the figures and letters
inarked thereon.
a is the
Fig. 1 is an elevation of apparatus in which a jet burner is used for indicating
the illuminating power of gas according to our Invention, and Fig. 2 is a sectional
view of the same; Fig. 3 shows our improved argand burner in section.
tube or case, in the upper part of which is fitted the tube b, the interior of which
is slightly taper (or conical), the larger diameter being at the top; c is the glass
tube secured to the bottom of the tube b; d is a rod or wire, to each end of which
is fixed a disc; the upper disc is rather smaller than the smallest diameter of the
tube b, and the lower disc (or pointer) is perforated or of such a size as not to
interfere with the flow of gas; e is the index plate, on which are marked figures to
denote the illuminating power of the gas to the required standards.
Inside the double tubular part ƒ (see Fig. 3) of the argand burner we place at
the bottom a ring or washer 9 of wool or other material, through which the gas
must pass before issuing from the top of the burner to be consumed; h is an annular
disc of gauze or other perforated. material, through which the air for combustion
passes to the flame; i is the annular diaphragm or cap that fits on the top of the
chimney ; to regulate the flame; the products of combustion pass through the
aperture in the cap i; k is a plate through which the chimney passes; the plate k
also serves as a gauge for the height of flame when a jet burner is used; when an
argand burner is used the plate k may be placed at a lower level to serve as a gauge
for the height of the flame, or a line o (see Fig. 3) may be marked on the chimney;
7,7, are rods connecting the plate k to the plate m; there are holes in the latter to
admit the burner and air for combustion; n is a short conical tube to guide the
air towards the flame; p is the pipe through which the gas is admitted to the
apparatus.

page_text: It is known that to maintain a flame at a given height for a certain time the
quantity of gas will vary as the illuminating power of the gas varies. We use by pre-
ference a seven inch jet flame, or an argand flame of, say, three inches high, attached to
our indicating apparatus. The mode of operation is as follows:-The gas to be tested
in ascending through the tubes c and b acts on the disc at the upper end of the
rod d, and raises the rod according to the quantity of gas passing to the burner to
maintain the given height of flame; the disc or pointer on the lower end of the
rod d indicates the figures on the index plate e, which denote the illuminating
power of the gas.
Having stated the nature of our Invention, and described the manner of
performing the same, we declare that we claim,—
The method of indicating the illuminating power of gas, and the combination and
arrangement of parts for effecting the same, substantially as herein shown and
described.
In witness whereof, I, the said Robert Tasker, for myself, and on behalf of
the said Thomas Thorp, have hereunto set my hand and seal, this Twentieth
day of August, One thousand eight hundred and eighty one.