IMPROVEMENTS IN SUSPENDED GAS LAMPS
Year: 1867

page_text: LETTERS PATENT to Mark Rollason, of Birmingham, in the County of
Warwick, Modeller, for the Invention of "IMPROVEMENTS IN SUSPENDED
GAS LAMPS."
Sealed the 5th May 1868, and dated the 9th November 1867.
PROVISIONAL SPECIFICATION left by the said Mark Rollason at the
Office of the Commissioners of Patents, with his Petition, on the
9th November 1867.
I, MARK ROLLASON, of Birmingham, in the County of Warwick, Modeller,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
SUSPENDED GAS LAMPS," to be as follows:-
My Invention has reference to suspended gas lamps, such as are ordinarily
used for halls and vestibules, and consists of the following arrangement or
combination of parts for raising and lowering the lower part of the gas shade
or globe surrounding the burner for the purpose of facilitating the lighting
of the lamp. In the axis of the metal ring by which the upper part of the
globe or shade is supported a tube is fixed, the lower end of the tube being
by preference about the level of the gas jets, which are situated on either
side of it. The said tube is supported by a cross arm carried by the metal
ring; the lower part of the globe or shade has a rod or tube fixed in its axis,
which rod or tube is of a size proper to slide in the tube fixed in the axis of
the ring carrying the upper part of the globe or
tube carrying the lower part of the globe or
fized tube by a stud which engages in a slot in
shade.
This sliding rod or
shade is connected with the
the fixed tube; the top of

page_text: this slot is turned at right angles, and constitutes with the said stud a fastening
similar to a bayonet joint. Besides the said stud the sliding rod or tube is
provided with a flat spring on one or on opposite sides, which spring or springs
by pressure against the inside of the fixed tube produce sufficient friction to
preserve the said sliding rod in any position in the fixed tube to which it
may be brought. In order to raise the lower part of the globe or shade it
is pushed upwards by a knob at its under side, when its rod slides up the
fixed tube; by now turning the knob through a small angle the said lower
part of the globe or shade is fixed in its raised position. Instead of using
the springs described the sliding rod or tube may be made to pass through a
stuffing box, and the required friction to support the lower part of the globe
or shade be thereby produced. In order to depress the lower part of the
globe or shade for lighting the lamp or other purpose the knob on the under
side of the said lower part is turned in a direction proper to liberate the
sliding rod and permit it to slide in the fixed tube; the said lower part of
the globe or shade may now be depressed to the required extent. The said
lower part of the globe or shade will remain at any height to which it may
be brought by the action of the springs or stuffing box described.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Mark Rollason in the Great Seal Patent Office on the
6th May 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, MARK
ROLLASON, of Birmingham, in the County of Warwick, Modeller, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of November, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Mark Rollason, Her special licence, that I, the said Mark Rollason, my
executors, administrators, and assigns, or such others as I, the said Mark
Rollason, 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 SUSPENDED GAS
LAMPS," upon the condition (amongst others) that I, the said Mark Rollason,

page_text: 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 Mark Rollason, do hereby declare the
nature of the 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 thereof, that is to say :-
My Invention has reference to suspended gas lamps, such as are ordinarily
used for halls and vestibules, and consists of the following arrangement or com-
bination of parts for raising and lowering the lower part of the gas shade or
globe surrounding the burner for the purpose of facilitating the lighting of
the lamp. In the axis of the metal ring by which the upper part of the
globe or shade is supported a tube is fixed, the lower end of the tube being
by preference about the level of the gas jets which are situated on either side
of it. The said tube is supported by a cross arm carried by the metal ring.
The lower part of the globe or shade has a rod or tube fixed in its axis, which
rod or tube is of a size proper to slide in the tube fixed in the axis of the ring
carrying the upper part of the globe or shade. This sliding rod or tube
carrying the lower part of the globe or shade is connected with the fixed tube
by a stud which engages in a slot in the fixed tube; the top of this slot is
turned at right angles, and constitutes with the said stud a fastening similar
to a bayonet joint. Besides the said stud the sliding rod or tube is provided
with a flat spring on one or on opposite sides, which spring or springs by
pressure against the inside of the fixed tube produce sufficient friction to
preserve the said sliding rod in any position in the fixed tube to which it may
be brought. In order to raise the lower part of the globe or sbade it is pushed
upwards by a knob at its under side, when its rod slides up the fixed tube.
By now turning the knob through a small angle the said lower part of the
globe or shade is fixed in its raised position. Instead of using the springs
described the sliding rod or tube may be made to pass through a stuffing box,
and the required friction to support the lower part of the globe or shade be
thereby produced. In order to depress the lower part of the globe or shade
for lighting the lamp or other purpose the knob is turned in a direction proper
to liberate the sliding rod and permit it to slide in the fixed tube. The said
lower part of the globe or shade may now be depressed to the the required
extent. The said lower part of the globe or shade will remain at any height

page_text: to which it may be brought by the action of the springs or stuffing box
described.
Having explained the nature of my Invention I will proceed to describe,
with reference to the accompanying Drawing, the manner in which the same
is to be performed.
Figure 1 represents in elevation the lower portion of a hall lamp constructed
according to my Invention; Figures 2 and 3 are parts of the same separately.
The same letters indicate the same parts in each Figure of the Drawing.
a is the metal ring supporting the upper or fixed part of the globe or shade,
the said ring being suspended by the ordinary rods. In the axis of the ring a
a tub b is fixed; this tube is shown separately in Figure 2. The said tube b
is fixed in the ring a by being screwed into a cross arm carried by the said
ring a. The tube 6 is fixed after screwing it in its place by the pin c. In the
said tube b is a longitudinal slot d, and at the top of the said slot d is a cross
slot d. The gas jets are situated on either side of the tube b. The lower
part of the shade or globe is carried by the metal ring e, somewhat larger in
diameter than the ring a. On the lower ring e, and fixed in the axis thereof
by screwing, is a rod or tube f (shown separately in Figure 3), which rod or
tube is of less diameter than the fixed tube b. The said rod f is introduced
into the tube b, and connected thereto by the pin or stud 9 working in the
slot d. The said ping with the slots d, d², constitute a bayonet joint fastening.
On opposite sides of the rod or tube f bow-shaped springs h, h, (see Figure 3)
are fixed, which springs when the rod is introduced into the tube bare
compressed, and by their pressure against the inside of the fixed tube produce
sufficient friction to preserve the sliding rod f in any position in the fixed
tube b to which it may be brought. In order to raise the lower part of the
globe or shade it is pushed upwards by the ornamental knob i at its under
side when the rod f slides up the tube 6, the stud 9 being brought to the top
of the slot d. The lower part e of the shade is supported in its raised position
by the springs h, h; but in order to secure it firmly in its place the knob i is
turned through a small angle. The stud g is thereby caused to engage with the
cross slot d', and fix the lower part of the shade in its raised position. When
the lower parts of the globe or shade is required to be depressed from the
fixed upper part a for lighting the lamp or for cleaning the shade the knob i
is turned so as to liberate the pin g from the cross slot d³, when the rod f is
at liberty to slide in the tube b, and the lower parte of the globe may be
lowered to the position represented in Figure 1 by pressure upon the knob i.
I is the ordinary ornamental rim between the two halves of the globe or shade,
and m is one of the suspending rods.
g

page_text: Figure 4 represents the arrangement of my Invention in which a stuffing
box is employed to support the sliding rod and lower part of the globe or
shade instead of the springs described and represented. k is the stuffing box
fixed in the axis of the ring a of the upper part of the globe; f is the sliding rod
or tube on the ring e of the lower part of the globe, the said rod or tube
passing through the stuffing box, the descent of the rod in the stuffing box
being limited by the enlarged end of the said rod. By means of the stuffing
box k the rod f and the lower part of the globe e carried by it are supported
at any height to which they may be brought. To raise or depress the lower
parte of the globe it is only necessary to lift or press upon the knob i, when
the rod f slides through the stuffing box k, and the lower part of the globe
may be raised or lowered to the desired extent. The arrangement of parts
represented in Figures 1, 2, and 3 for fastening the lower part of the globe
in its raised position may be applied if thought desirable to the arrangement
of my Invention represented in Figure 4.
Having now described the nature of my Invention, and the manner in
which the same is to be performed, I wish it to be understood that I do not
limit myself to the precise details herein described and illustrated, as the same
may be varied without departing from the nature of my Invention; but I
claim as my Invention the improvements herein-before described and illus-
trated in the accompanying Drawing, in raising and lowering the lower part of
the globes or shades of suspended gas lamps, that is to say, by means of a rod
or tube connected with the ring of the lower part of the globe or shade sliding
in a fixed tube connected with the ring of the upper or fixed part of the globe
or shade, the said sliding rod or tube being supported in the fixed tube either
by springs or by a stuffing box, and fixed when in its raised position by a
bayonet joint fastening, substantially as described and illustrated.
In witness whereof, I, the said Mark Rollason, have hereunto set my
hand and seal, this First day of May, in the year of our Lord One
thousand eight hundred and sixty-eight.
Witness,
RICHARD SKERRETT,
Clerk to George Shaw,
Birmingham.
MARK ROLLASON. (L.B.)