AN EXPANDING COMPENSATING SLIDE FOR SUSTAINING GAS AND OTHER LIGHTS, ALSO APPLICABLE FOR OTHER SIMILAR PURPOSES
Year: 1856

page_text: LETTERS PATENT to Joseph Chatwin, of Birmingham, in the County of
Warwick, Gas Fitting and Lamp Manufacturer, for the Invention of
"AN EXPANDING COMPENSATING SLIDE FOR SUSTAINING GAS AND OTHER LIGHTS,
ALSO APPLICABLE FOR OTHER SIMILAR PURPOSES."
Sealed the 9th June 1857, and dated the 11th December 1856.
PROVISIONAL SPECIFICATION left by the said Joseph Chatwin at tho
Offico of the Commissioners of Patents, with his Petition, on the 11th
December 1856.
I, JOSEPH CHATWIN, of Birmingham, in the County of Warwick, Gas
Fitting and Lamp Manufacturer, do hereby declare the nature of my said
Invention for "AN EXPANDING COMPENSATING SLIDE FOR SUSTAINING GAS AND
OTHER LIGHTS, ALSO APPLICABLE POR OTHER SIMILAR PURPOSES," to be as follows
(that is to say)-
The object of my Invention is to dispense with the use of a counterpoise or
balance weights, with their attendant chains, pulleys, and other parts, as
usually applied to gas and other chandeliers. I effect this by securing on the
inner tube or piston rod, just above or near the packing, two or more strong
expanding springs, so formed that a large portion of their ends shall be curved
lengthway, that when collapsed and pushed into the outer tube the curved ends
shall nearly fill up the interior circumference of the outer slide; thus an equi-
valent is obtained capable of regulation according to the strength of the

page_text: springs, which must vary according to the taste, style, or number of lights
desired to be sustained. This object I also propose to effect in some instances,
where it may be desirable, by using helical springs placed in such a way that
they shall exert a power or pressure in a radial direction between the inner
and outer tubes or cap fitted on the outer tube. The same result or an equi-
valent will be obtained by fastening the springs on the interior of the outer
tube or slide, the springs in that case exerting their force by pressing on tho
outside of the inner slide or piston. This contrivance is applicable for many
useful purposes where a sliding or telescopic action is required, yet capable of
sustaining itself in any position in which it may be placed.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Joseph Chatwin in the Great Seal Patent Office on the 11th
· June 1857.
ΤΟ
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPп
CHATWIN, of Birmingham, in the County of Warwick, Gas Fitting and Lamp
Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Putent, bearing date the Eleventh day of December, in the year of our Lord
One thousand eight hundred and fifty-six, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Joseph Chatwin, my executors, administrators, and assigns, Her special licenso
that I, the said Joseph Chatwin, my executors, administrators, and assigns, or
such others as I, the said Joseph Chatwin, my executors, administrators, or
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 EXPANDING COMPENSATING SLIDE FOR SUSTAINING GAS AND OTHER LIGHTS, ALSO
APPLICABLE FOR OTHER SIMILAR PURPOSES," upon the condition (amongst others)
that I, the said Joseph Chatwin, by an instrument in writing under my hand
and seal, 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 Joseph Chatwin, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,

page_text: to be particularly described and ascertained in and by the following statement
(that is to say)—
The object of my Invention is to supersede the use of weights as a counter-
poise for regulating the slides of gas and other chandeliers, gas pendents, and
such like articles, whereby much economy is insured, and many evil conso-
quences avoided, by dispensing not only with the weights and their attendant
pulleys, chains, &c., but the mischievous consequences that frequently occur
from the breaking or giving out of the chains to which the weights are
attached; and this object I effect by the use of a spring or springs bearing on
or abutting against the internal slide or piston, and which spring or springs
may be regulated with a screw or screws, or indian-rubber rings, or packing;
and which indian-rubber rings or suitable packing may be used in connection
with metallic springs, or by themselves, as circumstances may require.
But the clear nature of my Invention, and the manner in which the samo
may be carried into effect, will be well understood by referring to the Draw-
ings hereunto annexed, which I will now proceed to describe, reference being
had to the figures and letters marked thercon (that is to say):-
Fig. 1. represents a plain pendant or other slide, fitted with a cap A; in the
ordinary way for suspending. B, B, is the outer tube, shewn in section, fitted
also with a cap C, in the usual way. D, D, is the inner tube, to which is
attached the cork or other packing E, which fits the interior circumference of
the outer tubo in such a manner that the gas shall not escape; F is a collar,
to which is attached two moderately stiff springs, shewn in edge view, marked
u, a, on the ends of which are secured two metallic or other suitable plates,
marked b, b, which plates are curved to fit the internal area of the outer tube,
and these plates may be covered with leather or not, as desirable. Thus, it is
evident that the lateral or outward pressure imparted by the springs to the
plates b, b, that the outer tube in relation to the inner one will remain in any
position it may be placed in; and as the outer tube may be continued down
and fashioned or fitted in any desirable way with burner or burners, globe or
globes, the said burner or burners may be raised or lowered at convenienco
without the necessity of unusual or inconvenient exertion; but inasmuch as
the glass shades or globes fitted to such pendents or slides vary in their size
and weight, as also do many of the other parts, I have found it necessary to
provide some means for adjusting or varying the outward pressure of the
springs, according to the weight they have to sustain; and I effect this by
means of the nut c, which may be made to exert more or less pressure on the
inside of the springs, which will have the effect of spreading them out, and
also of shortening their bearings. The screw on which this nut works is of

page_text: course made hollow for the gas to pass down through it to the burner or
burners that may be attached to it; thus we have a regulating equivalent for
balance or counterpoising weights.
As my improvement entirely relates to this part, I have not thought it
necessary to exhibit the pendant or slide in a complete form, as it would
occupy much room, or compel me to draw the parts in which my Invention
consists so small as to make them not so intelligible and apparent.
Fig. 2 represents a part of a slide or pendant, the springs of which, in this
case, being attached to the larger or outer tube exert their pressure against
the inner one, which plan is preferable to the one exhibited at Fig. 1, as the
screw or screws that regulate the pressure are in a position for convenient use.
G is the inner tube, and H is the outer one; I, I, is a skeleton collar, secured
at the bottom to the water cup, shewn in section at J, J, which water cup is
attached to the under slide H by tapping. The skeleton collar has a circular
hole at the top and bottom for the tube G to pass freely up and down.. d, d,
are two flat springs of steel, shewn in such a position as to exhibit their edges;
at the ends of these springs curved pieces of metal or other material, marked
e, e, e, e, are secured, the inner curved surfaces of which assimilate to the out-
ward area of the inner tube G, against which they exert their force, and
which force may be increased or diminished by the thumb screw f; and in
order to secure a clear central action I sometimes use two thumb screws, the
one on the other side being represented in dotted lines. 9, 9, is simply a
sectional view of a case introduced for the purpose of obscuring the springs,
the form of which case may be greatly diversified or ornamented if required.
Fig. 3 is the same as Fig. 2, representing the springs entirely hid by the
case or cap g, and with the regulating screw put in front. The rings h, h, aro
simply for attaching ornamental chains, that are sometimes attached to
two light pendants; the dotted lines k, k, merely shew that the cap 9 may
be made in that or any other suitable form.
Fig. 4 represents a slide, with the springs m and n secured at their
lower ends to a collar, marked o, which collar is secured to the lower or
outer tube K. The lengthway form of the springs may be varied, as hero
represented, m being curved outward and n represonted straight; but at the
upper ends of these springs pieces of curved metal are secured, marked p, p,
in like manner as described at e, e, Figure 2, and which pieces or clips of
metal may be secured by soldering, rivetting, or otherwise. And the means
I propose to regulate the pressure of the curved parts p, p, upon the inner
tube L (which in some cases may be important), is by using elastic rings
of indian-rubber, as shewn by the dotted lines q, q; but as such rings cannot

page_text: be placed in this position without taking the slide to pieces, it
may. be
preferable to use a pin on one or on both of the plates p, such as exhibited
at r, around which pin or pins elastic bands can be stretched, which will
have the same effect as the elastic bands shewn in position at q. .The
water cup s, s, is shewn in section, and may be attached to the lower tube.K
or or to the collar o, and may extend high enough and of such a form as to
hide or obscure the springs if desired.
Fig. 5 represents a slide for a chandelier or pendant, with a water.cup t,.t,
shown in section; and the necessary springs for holding or retaining the inner
tubo M (in any position required in relation to the lower or outer one,
marked N,) are removed for the purpose of avoiding confusion. The cup.t, t,
is represented as secured to the lower tube by tapping, but any other means of
attachment may be adopted; and the part of the lower tube that rises up
abore where the water cup is united is split down in three parts, as at from
u to u, and may be gathered in or reduced a little in its circumference.
-
Fig. 6 represents a transverse section of the last Figure, as taken through
the dotted line v, v, shewing the end of the lower tube N.divided into.threo
parts marked w, w, w¹; and x, x, x, represent the outer ends of a triangular.box,
which may be cast in iron or brass, or otherwise formed, for holding threo
helical springs, in the manner as represented in the compartment.marked w¹.
The radial extent of this triangular spring box is the same size as the interior
of the upper part of the water cup, here shewn in a top view, marked with the
letters t, t, as in the sectional view of the same part at Figure 5. The springs
in the spring box are intended to be regulated by screws, as represented at y;
the screw passing through the top rim of the water cup, and the outer ends of tho
spring box will unite these parts together without any other means being required.
In some instances it may be convenient to divide the spring box into two or
four radial compartments, according to the weight required to be sustained;
and instead of using helical or metallic springs, suitable shaped pieces of india-
rubber may be used, such pieces of indian-rubber, to be relieved or compressed
as required by means of thumb screws, as hero shewn; or pieces of indian-
rubber or other suitable elastic material may be used int connection with
helical or other springs; the said pieces of indian-rubber &c., being applied
between the ends of the springs, and the divided parts of the lower tube,
marked w, w, w, as the ends of the helical springs would abut better against
an elastic packing of that kind than against the curved surfaces of the divided
tube.
I shall not attempt to further elaborate on the various modes and modi-
fications of which my Invention is capable of assuming (for the objects named

page_text: in the title of this my in part recited Letters Patent) as the same principle
can be applied in an endless variety of ways; as, for instance, instead of using
the skeleton collar or frame, marked I, I, in Figure 2, the cap g, shewn in
section in Figure 2, and.in a side view at Figure 3, may be made to answer
for both purposes, as the screws may be tapped through the belt that surrounds
it, as shewn at a, a, in Figure 7, which represents the same arrangement as at
Figure 2, but with the skeleton collar I dispensed with; and the springs
required in this instance may be cut out of sheet steel in the form required
without applying any other pieces for bearings, as represented and described
at e, e, Figure 2, thus making the arrangements very simple, efficient, and
economic.
Having thus described the nature of my Invention, and the manner in
which the same may be carried into effect, I wish it understood that I do not
. set up any claim for the shape, measurement, size, or strength of any of the parts
herein exhibited or described, as the whole may be varied according to circum-
stances and requirements; but what I do claim as my Invention is, the regu-
lating of sliding or telescopic action of chandeliers, gas pendants, and such like
articles by the use of a spring or springs so arranged as herein exhibited, that
the force of such spring or springs may be exerted against the surfaces of the
sliding parts, by which means the objectionable and expensive use of pendent
or counterpoising weights are entirely superseded.
In witness whereof, I, the said Joseph Chatwin, have hereunto set my
hand and seal, this Tenth day of June 1857.
JOSEPH CHATWIN. (L.S.)
Witness,
GEO. ALEX. HARRIS,
Clerk to J. S. Cockings, Patent Agent,
26, Ann St., Birmingham.