IMPROVED APPARATUS FOR USING THE LIME LIGHT FOR THEATRICAL REPRESENTATIONS AND OTHER PURPOSES
Year: 1870

page_text: PROVISIONAL SPECIFICATION left by Edward John Cowling Welch
at the Office of the Commissioners of Patents, with his Petition,
on the 4th March 1870.
I, EDWARD JOHN COWLING WELCH, of Eden Works, Hampstead,
Road, in the County of Middlesex, do hereby declare the nature of the
said Invention for "IMPROVED APPARATUS FOR USING THE LIME LIGHT FOR
THEATRICAL REPRESENTATIONS AND OTHER PURPOSES," to be as follows:-
:-
The object of this Invention is to obviate the difficulty besetting the
ordinarily constructed lime light apparatus as used at theatres, which is
such that a separate man, has to attend and hold each lime light, and
in pieces where much lime light is required, this increases the expenses
a considerable amount.
The apparatus which forms the subject of this Invention can be
managed by one man, who can direct all the lime lights on the stage,
and by the movement of a handle change the colour of the light and
turn it about and direct the rays to any part of the stage as required.
An ordinary lime light apparatus is placed on a suitable frame or
stand. This is supported at either end by brackets or other supports

page_text: round the circular rack, but
fastened to the wall. To the stand or frame is attached a lower frame,
upon which the upper frame can turn in a horizontal plane, and to this
are fastened suitable sockets of the same internal diameter as a bore
made in the brackets. Through these sockets passes a hollow pin which
causes the brackets to support the frame, the hollow pin passing through
the bracket and the socket, forming as it were a hinge joint by which
the lower frame can turn round in a vertical plane between the brackets.
The upper frame having its axis at right angles to the lower conse-
quently turns up and down in the vertical plane with it. To the
upper frame, and passing through spaces in the lower frame, are two 1
small bearings carrying an axle, on which is a toothed wheel with
elliptical teeth which gear into a circular rack, the ends of which pass
through the hollow pins of the bearings, and by moving this backwards
or forwards the axlo is made to revolve. On to this axle is fastened a
circular plate, which carries the different coloured glasses, so that by
moving the circular rack to any certain distance, any particular coloured
glass presents itself in front of the light. The frames when moving in
the vertical plane carry the toothed wheel
the circular rack is prevented turning by a small key and key way, so
the position of the "spectacle plate" is not
frames. By the side of the circular rack is
in the brackets or supports. A curved pin
to this, and this pin passes through a small stud on the upper frame.
This stud is a short distance from the centre of revolution of the upper
frame, and by sliding this rod backwards and forwards the upper frame
is caused to revolve on the lower frame in a horizontal plane, a pin
passing up from the lower frame through the centre of the upper frame,
where it is secured by a nut or other fastening. When the lower frame
(carrying the upper one) moves in its vertical plane, (the sliding rod for
the circular motion of the upper frame not being at the centre of
motion of the said lower frame) the pin from the sliding rod moves
slightly backwards and forwards in the stud of the upper frame, and at
the same time the stud turns the sliding rod round on its own axis.
When the upper frame (which carries the light apparatus and the pinion
wheel and spectacle plate) turns round, the elliptical form of the teeth
of the pinion allow it to move round a sufficient amount in the rack
without affecting its working, as the centre of motion of the upper
frame is directly over the point of gearing of the rack and pinion. The
weight of the parts in front of the rack is enough to cause the machino
altered with regard to the
another rod sliding in holes
stands out at right angles

page_text: to fall always forward, that is with the light pointing downwards. A
short arm which extends from the lower frame towards the wall behind,
when pulled downwards lifts up the frame in front, and to this arm
and to both the circular rack and the sliding rod are attached wires or
rods or chains which lead down to where the lime light man is stationed,
the apparatus itself being fixed up above, either in the "wings" or in the
"flies" or elsewhere. The ends of each of the wires or rods are attached.
to a small lever on a frame, these three levers being more conveniently
placed on the same axis, the one moving the coloured glasses working on
a notched quadrant so as to remain fixed at any colour whilst the light
is directed about the stage. The wires pull the parts to which they are
attached in one direction, and suitable springs or balance weights
which are fixed up at the lamp, pull them back in the opposite direction.
The connections between the fixed supply pipes for the gas and the lime
light itself are formed by means of flexible tubings, and the supplies of
gas are regulated by small cocks or valves by the side of the handles for
moving the lamp. By these means one man can regulate all the lime
lights on the stage.