IMPROVE- MENTS IN THE CONSTRUCTION OF CHIMNEYS FOR GAS BURNERS AND OIL AND دو
Year: 1871

page_text: LETTERS PATENT to James Verity, of No. 1, Carlton Road, Kentish
Town, in the County of Middlesex, for the Invention of "IMPROVE-
MENTS IN THE CONSTRUCTION OF CHIMNEYS FOR GAS BURNERS AND OIL AND
دو
Sealed the 22nd March 1872, and dated the 23rd September 1871.
PROVISIONAL SPECIFICATION left by the said James Verity at the
Office of the Commissioners of Patents, with his Petition, on the
23rd September 1871.
",
I, JAMES VERITY, of No. 1, Carlton Road, Kentish Town, in the County
of Middlesex, do hereby declare the nature of the said. Invention for
"IMPROVEMENTS IN THE CONSTRUCTION OF CHIMNEYS, FOR GAS BURNERS AND OIL
AND OTHER LAMPS, AND IN REFLECTORS AND PROTECTORS FOR THE SAME," to be
as follows:-
'
1
11
1
.
Firstly. In manufacturing such chimneys and reflectors of thin sheets
of mica. In carrying out my Invention I take a piece of mica and split
into sheets or plates of the thickness required, and cut the same into
lengths and breadths to form the size of the chimney. I then insert
one side of the sheet or sheets of mica into the groove or fold of a metal
"

page_text: bar placed on a frame or block, and then hammer down the groove
or fold tight over the edge or edges of the mica. The sheet of mica thus
fixed in the bar is then fitted on to a mandril when the opposite side of
the mica is brought round the mandril and inserted into a second groove
or fold of the metal bar and hammered down in like manner, when it
will be formed into a cylinder which is retained on the mandril to receive
a metal rim and collar upon each of its ends; the rim is placed between
the mandril and cylinder, the collar is then placed on the outer side of
the cylinder, and the whole placed in a lathe and put in motion, a strong
pressure is applied to the collar until all becomes firmly compressed
together, the chimney is completed without the use of pins, clips, rivets,
screws, or solder. I also finish the cylinder with a double metal rim on
each of its ends and treat them in a lathe in the same manner as above.
For the purpose of making the chimneys more durable and substantial I
use two or more sheets or plates of mica placed one within the other, and
for still greater strength I use two perpendicular metal bars placed at
right angles, and use the mica to make the cylinder in two longitudinal
sectional parts of the circumference of the chimney required, and¸finished
in like manner to the first.
The second part of my Invention consists in making such chimneys
reflect their own light by placing the reflecting medium between two of
the plates of mica previous to their being fixed in the metal bars. I also
make the reflector for the chimneys by using a piece of the reflecting
medium of the size required, and cover it with a thin sheet of mica and
bind the edges with sheet metal, and place it when wanted inside the
chimney between the upright metal bars.
The third part of my Invention consists in forming protectors, to
be used in conjunction with the mica chimneys, of mica cut into
shapes to form a cone, and fitted into a frame made of three metal bars
placed on a conical mandril; the edges of the sheets of mica to form the
cone are placed within the grooves or folds and hammered tight down.
On the top of the cone two metal caps are placed, one inside the other
outside; the screw leg of a metal knob is then passed through holes
formed in the caps enclosing the points of the mica and bars, and with a
screw nut and washer placed on the screw leg inside the top of the cone
and screwed up tight, the whole of the parts are fitted firmly together
completing the cone and forms the protector. To the inside of the metal
bars of the cone I fix three metal legs to rest on and firmly grip the top

page_text: of the chimney, by which means the heat and flame is completely con-
fined within the cone and chimney; it can also be applied to chimneys
used in out-door shop lanterns to protect the light from down draft and
rain.
The fourth part of my Invention is for economising the gas burnt in
chimneys by means of a throttle valve. I cut a stout piece of mica into
the form of the top of the chimney only less in diameter by three-eighths
of an inch or more according to the size of burner and chimney; when
properly adjusted I place its edges in the groove of a metal ring and then
place a metal bar across the centre, and in the centre of both I punch a
hole through which I put the leg of a metal knob, and with a screw nut
on the under side of the mica and bar are screwed up tight together, the
ends of the metal bar being fixed into a metal rim made with a flange to
fit the top of the chimney in such a manner that the valve dips into the
chimney as desired.
The fifth part of my Invention consists in calcining mica for pro-
ducing a reflecting medium for mica chimneys and for reflecting
purposes generally. I select the most suitable pieces of mica and cut
them into economical sizes and place them in a retort at a red heat,
O afterwards raised to a white heat; the period of the process of calcining
depends upon the quality and thickness of the mica, 'occupying from five
to fifteen hours, and when it has assumed the colour of molten silver it
is taken from the retort and allowed to cool, when it is ready for use.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Verity in the Great Seal Patent Office on
the 23rd March 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES'
VERITY, now residing at No. 1, Carlton Road, Kentish Town, Middlesex,'
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-third day of September, in the
year of our Lord One thousand eight hundred and seventy-one, in the,
thirty-fifth year of Her reign, did, for Herself, Her heirs and successors,

page_text: give and grant unto me, the said James Verity, Her special licence
that I, the said James Verity, my executors, administrators, and assigns,
or such others as I, the said James Verity, 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 THE CONSTRUCTION OF MICA
CHIMNIES FOR GAS BURNERS AND OIL AND OTHER LAMPS, AND IN REFLECTORS AND
PROTECTORS FOR THE SAME," upon the condition (amongst others) that I,
the said James Verity, 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 Verity, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the
following statement, that is to say :-
My Invention consists in an improved method of making mica
chimnies for gas burners and oil lamps, and for employing a reflecting
medium therein, and for employing a reflecting medium, also for making
protectors for the same, and for valves for the economizing of gas burnt
in the same, and for a method of making a reflecting medium from mica,
according to the processes herein-after named.
For making the mica chimnies I take peices of mica and slit them into
sheets or plates of the required thicknesses and cut the same into lengths
and breadths to form the chimney to the size wanted to be made. I then'
take the mica thus prepared and place one of the longest sides into one
of the folds of a double folded metal bar previously prepared, and place
them on a flat wooden block and hammer the fold tight down upon the
edge of the mica placed therein with a wooden hammer or mallet which
firmly secures the mica in the bar, it is then removed on to a mandril
and the opposite side of the mica is pressed round the mandril into the
second fold of the bar, when it is hammered down tight upon the mica
edge therein upon the mandril, it is then formed into a cylender without
the use of pins, rivets, clips, screws, or solder; the cylinder is retained

page_text: on the mandril to receive a metal rim and collar upon each of its ends,
the rim is placed between the mandril and the inner part of the cylinder,
and the collar is placed on the outer part and pressed upwards on to the
bottom edge of the inner rim, the whole is then placed in a lathe, the
lathe is put in motion and a pressure put on the collar which fixes all
firmly together; the chimney is completed and the (mandril withdrawn)
without the use of pins, rivets, clips, screws, or solder.
The rims and collars are made in the following manner:-The inner
rims are made of tubing of the required diameter, and cut off in widths
of three-eights of an inch; the outer rim or collar is cast to a required
diameter with a flange inward of the circle one-eighth of an inch wide, it
is placed in the lathe and smoothed; in the inside of the flange a small
groove is cut and a slot in the inside side of the collar for the end of the
bar of the cylinder to bed in, they are then ready for use.
The mandril employed is made of metal in three sectional parts; the
centre part is made wedge-shaped with a dovetail bar on each of its
sides to slide into a dovetailed groove in each of the other sectional
parts forming the mandril, when the mandril is to be withdrawn the
centre peice is struck and the mandril removed.
I also finish the above cylinder with double metal rims fixed on
each of its ends, and finish them in like manner to the first. These rims
are made in the following manner :-They are cast to a given diameter
one-eighth of an inch thick and three-eighths of an inch wide, placed in
a lathe and smoothed, a groove is cut down the centre of the rim all the
way round to within one-sixteenth of an inch of its entire depth, a slot is
cut in the inside side for the metal bars to bed in.
For the purpose of making the chimnies more substantial and durable
I use two or more sheets or plates of mica placed one within the other,
and for still greater strength I use two double-folded metal bars and use
the mica in two longitudinal sectional parts of the circumference of the
chimney to be made; the work is performed and the chimney finished in
like manner to the former.
They may be made another way. Two double-folded metal bars are
prepared half an inch longer at each end than the mica to be used to
form the cylinder, lay one of the bars thus prepared on a wooden block,
take one of the two sectional parts of the prepared mica to form the
cylender, and place one of its longest sides into one of the folds of the

page_text: bar, then take the other sectional prepared part of the mica, and place
one of its longest sides into the second fold of the bar, hammer down
the folds tight upon the mica therein, with the hand bend round the
other sides of the mica into the folds of the second bar and hammer all
tight together on a mandril or beak; then take two double metal rims
with two slots cut through the bottom of the groove of each rim, place
the projecting ends of the bars of the cylinder into the slots of the rims,
press the cylinder down to the bottom of the groove, bend down the
projecting ends of the bars over the slot on the outer edge to keep the
rims and bars in their place until the slots are tight closed with a
hammer on a beak till the bars and cylinder is firmly fixed, it is then
finished.
To make the chimnies reflect their own light, place the reflecting
medium between two of the plates of mica used in making the cylinder
previous to their being plac'd in the metal bars. I also make the
reflectors for the chimnics by using a peice of the reflecting medium the
size required and cover it with a thin sheet of mica and bind the edges
with sheet metal, and place it when wanted inside the two perpendicular
bars of the chimney.
I make the protectors to be used in conjunction with the chimnies, of
mica split into sheets of the required thickness, and cut into shape to
form a cone and fitted into a frame made with three metal bars placed
upon a conical mandril, the edges of the sheets of mica to form the cone
are placed within the groove or folds formed in the metal bars and
hammered tight down upon the mica. On the top of the cone two :
metal caps are placed, one inside the other outside; a screw leg of a
metal nob is passed through boles formed in the caps enclosing the points
of the mica and bars, with a screw nut and washer placed on the screw
leg inside the top of the cone it is screwed up tight by which means the
whole of the parts are fitted firmly together, which completes the cone a
and forms the protector. To the inside of the metal bars of the cone I
fix three metal legs to rest on and firmly grip the top of the chimney,
by which means the heat and flame of the gas is confined within the
cone and chimney; the cone is also to be applied to the chimnies used in
the out-door shop lanterns, to protect the light from downward draught ;
and rain.
For economizing the gas burnt in the chimneys I proceed in the.
following manner :— -I cut a stout piece of mica into the form of the

page_text: chimney only less in diameter by three-eights of an inch; when adjusted
to the size its edges are placed in the groove of a metal rim, I
place a metal bar across its centre, and punch a hole through both at
their centres and pass the leg of a metal nob through the holes to the
under side, and with a screw metal nut placed on the leg of the nob the
bar and mica are screwed tight together; the ends of the metal bar are
then fixed into a metal ring made with a flange to fit the top of the
chimney in such a manner that the mica valve dips into the chimney
according to requirements.
To make these reflecting mediums I take peices of mica suitable for the
purpose wanted, to be all of one thickness at each calcining so that they
will be calcined equally, have the retort ready at a red heat, place the
selected mica in it and close up the mouth of the retort with an iron
plug, raise the heat of the retort to a white heat. Thin sheets of mica
can be calcined in five 5 hours, but mica one-quarter of an inch thick will
take fifteen hours. The test is if it assumes the color of molten silver;
when cooled from the retort it is fit for use.
I claim for making the mica chimneys with two or more plates of
mica without pins, rivets, clips, screws, or solder.
hereunto set my
In witness whereof, I, the said James Verity,
hand and seal, this Twenty-third day of March, in the year of
our Lord One thousand eight hundred and seventy-two.
Witness,
FREDERICK RUSSELL,
4, Gillies Street,
Kentish Town,
Middlesex.
(L.S.) JAMES VERITY.