An Improved Form of Jet for Optical Lanterns.
Year: 1893

page_text: Date of Application, 15th Mar., 1893
Complete Specification Left, 19th Sept., 1893-Accepted, 28th Oct., 1893
PROVISIONAL SPECIFICATION.
An Improved Form of Jet for Optical Lanterns.
I, JOHN HENRY BARTON, Lanternist and Mechanician of 18 Greame Street,
Moss Side, Manchester, in the County of Lancashire, England do hereby declare
the nature of this invention to be as follows :-
My invention consists of one or more plates or discs, which are caused by suitable
means to traverse on the back of the lantern, or on each other: by means of the
traversing motions of these plates or discs, the light is brought into correct position,
so far as regards its vertical and side adjustments. The motion for bringing the
light to, or from the condensor, is obtained by causing the tubes (and their
attachments) conveying the gases, to pass to and fro through the traversing plates; this
to and fro motion, may either be, by suitable mechanical means, or, by a simple sliding
motion actuated directly by the hand. The motions for turning and raising the
lime, altering the distance of the lime from the nipple, and for detaching the jet
from the lantern are attained by simple means.
Each, or any of the various motions may be omitted if desired.
The objects gained by this improved jet, are as follows;
1st. Its form prevents absolutely any light being emitted at the back of the
lantern, thus dispensing with the necessity for curtains or shields.
2nd. Greater simplicity of construction, without sacrifice of efficiency, thus
reducing cost of production.
Dated this Thirteenth day of March 1893
JOHN HENRY BARTON,
COMPLETE SPECIFICATION.
An Improved Form of Jet for Optical Lanterns.
JOHN HENRY BARTON 18 Greame Street, Moss Side, Manchester in the County
of Lancashire, England, Lanternist and Mechanician do hereby declare the nature
of this invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
The intention of this invention is primarily the construction of an optical lantern
limelight jet in such manner that it can be fitted to a lantern, and the necessary
adjustments of the light made without any light whatever being allowed to escape
from the back of the instrument as is the case with those of ordinary construction,
and to obviate which, either a curtain of some kind of material is employed, which
is inconvenient to the lanternist, or otherwise the light is allowed free course in the
room, which is an inconvenience to those persons at the rear of the lantern.
A further idea of the invention is, that the adjustments are more simple in
construction, and also arranged in such manner that the use of each portion is more
readily seen and comprehended, and consequently mistakes in manipulation are less
likely to occur, and there is also greater comfort generally to the lanternist.
In order to accomplish these objects a plate A is attached by the screws e (or
other suitable means) to the back of the lantern body; on this plate is superimposed
the plate B which traverses in a vertical direction on A, and is kept in position at
its lower portion by means of the pins d screwed into B and working in the slots f,
and at the upper portion by the block which is screwed into A at the portion
marked; at the sides of this block is a slight flange which projects on each side of
the slot k in plate B.

page_text: In this block there works a screw I having a milled head, this screw on being
turned, acts against the arm m fixed on B, thus raising or lowering B and forming
the vertical motion "of the jet.
For the purposes of the adaptability of the jet to any lantern, the plate A is
adviseable, but it is not absolutely necessary, and the plate B could be made to work
directly on to the back of the lantern, or plate A could itself form the back of the
lantern.
"
The plate C is pivoted to the plate B at n, and can be moved sideways in either
direction by means of the milled head H, into the back of which is fastened the
pin p which works in the slot r cut in C; this action forms the "side adjustment
of the light, and when the correct position is found, the milled head t carrying a
pin passing through H and screwing into B at a, clamps the plate C perfectly
secure.
In order to make C free itself of the plate B when this clamp is released, there
is a small prominence on C (at the side next to B) at the part marked u.
The tube E is made so as to pass to and fro in the tube F; these tubes are here
depicted as being circular in form, but any other form might be adopted if
preferred.
This to and fro motion may either be by "rack and pinion" as shown at N,
Fig. IV, or any other convenient method, or it might be a simple sliding motion
only. The shorter tube F is screwed into the plate C, the longer tube E is closed
at one end with the disc D, and into this disc are secured in the manner shewn in
the drawing, the tubes conveying the gases to the nipple. This disc D also carries
the outer portion of the lime turner, and also the outer portion of the motion for
altering the distance between the lime and nipple, and their motions will be readily
understood by reference to the drawings, K being the lime turner with its
"check" O, and L for altering the distance of lime from nipple.
The action of the tube E fitted with the disc D carrying the gas tubes with their
cocks and valves to and fro in the tube or sleeve F constitutes the motion for
adjusting the light to and from the condensor.
Fig. I shews A separate;
Fig. II B separate ;
Fig. III C separate;
Fig. IV, view of the parts in situ ;
Fig. V is a side view in section of Fig. IV and includes two planes in the one
view; ri. the centre of the whole jet, and the centre of the gas tubes and cock.
In addition to the aforesaid movements and motions the jet in its complete form
is fitted with "screw down valves" and with a "cut-off" but any of the
movements or motions may be omitted if greater simplicity is required. The
inside portions of the jet can be detached for cleaning &c. by unscrewing t, when
plate and all its attachments can readily be lifted from the pivot at n.
ولا
Where greater portability is desired the tube F and all its attachments, might
be sunk considerably further through the plates, by means of altering the position
of the flange of the said tube F.
The nozzle and nipple of the jet shewn is of the "mixed gas" order, but the
same system of adjustments is applicable to the form known as the "blow-through
lime light jet."
Fig. VI represents an alternative arrangement of the tubes through a plate or
disc, which method might be used when only such portions of this invention as
pertain to the excluding of the light from the back of the lantern was desired, but
it might also be used in combination with any other portions of this invention that
might be considered desirable, and a screw, or any convenient motion to actuate
the tubes to and fro through the plate or disc might be added.
It is not novel to employ a metal plate or disc fixed on the tubes of an optical
lantern jet as a means to shield the light, but uch plate or disc is a fixture on the
tubes and moves simultaneously with them, and so doing, stops back only a portion
of the stray light, whereas in this present invention, the plate or disc does not move

page_text: to and fro, but the tubes move through the plate or disc in the manner shewn in
the drawing, thus stopping back all stray light and also at the same time forming
the necessary to and fro motion of the jet which in the other instance above named
is only attained by means of a separate and additional motion, and differing
altogether from this present invention.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is;
1. The passing of the tubes of a lantern jet, (and their attachments) conveying
the gases to the nipple, through a plate, or plates, or discs in such manner that
no light whatever can escape from the back of the lantern, in any possible position
of the jet; substantially as figured and described.
2. The employment of plates or discs traversing on the back of the lantern, or
on each other, as a means of obtaining the "vertical" and "side" adjustments of
the light, and also the motions of the tubes aforesaid through such plate or plates,
or discs to form the to and fro motion from the condensor; substantially as figured
and described.
3. An oxy-hydrogen jet with adjustments and fittings substantially as figured
and described.
Dated this First day of September 1893.
JOHN HENRY BARTON.