Improvements relating to Photographic Cameras and to Apparatus for use in connection therewith.
Year: 1889

page_text: Date of Application, 28th Mar., 1889
Complete Specification Left, 21st Jan., 1890-Accepted, 8th Mar., 1890
PROVISIONAL SPECIFICATION.
Improvements relating to Photographic Cameras and to Apparatus
for use in connection therewith.
We, WILLIAM HENRY SMITH, of Upton Villa, Beckenham Road, in the County
of Kent, Engineer, and WILLIAM WILLIS, of Bromley, in the County of Kent,
Manufacturer, do hereby declare the nature of this invention to be as follows:-
Our invention relates to photographic apparatus, and one of its objects is to provide
improved means whereby sensitized plates or films may be conveniently transported
and may at any time be inserted in and removed from the camera without liability
to exposure of the said plates or films to light.
Our said invention, moreover, comprises an improved shutter hereinafter described
for facilitating exposures of short duration.
For holding the sensitized plates and transferring them as required to and from the
camera, we employ a holder or dark-slide which comprises a metal sheath or case one end
of which is open and is firmly attached to one side of a tube laving slots therein through
which the plates may be inserted in and removed from the said sheath. In the said
tube is fitted a plug or shutter of any suitable material. This plug is so formed that
the portion thereof which corresponds with the slots in the tube is semicircular or
of other convenient shape in transverse section so that it will, in one position, close
the opening or mouth of the sheath or case and thus exclude light, but, by turning
the said plug about its axis through a greater or less angle, a clear way through the
slots and the open end of the sheath may be made, through which the photographic
plate can be inserted or removed.
Our improved dark-slide is very compact and can be cheaply manufactured. More-
over tlie said dark-slides can be very closely packed so that a large number of them
may bo contained in a comparatively small space.
To provide for the use of our improved dark-slide on a camera, we attach to the
said camera a tube or portion of a tube with a slot in it through which a plate may
pass into or from the camera; this tube is of such internal diameter that the tube on
the aforesaid sheath or case will accurately fit and slide in it. The tube or socket on
the camera is, moreover, provided with a slot throughout or nearly throughout its
length to admit the sheath or case, so that the dark-slide can bo readily applied to or
removed from the camera. When the dark-slide containing the plate is slid into
position in the aforesaid tube or socket, and the plug is turned by a key or otherwise
through the required angle, the plate will fall through the slot in the said tube or
socket into the camera; grooves or other suitable means are provided in the camera
to hold the plate in a proper position therein. To remove the plate from the
camera, the latter is inverted and the operations above described are performed in
the reverse order.
In some instances, we provide a key or other device in one end of the tube or
socket on the camera, so that, by turning the dark slide through the required angle
after it has been inserted in the said tube or socket, the said dark-slide may be opened
and closed.
In other instances, we arrange within the tube or socket on the camera another
slotted tube capable of revolving therein and adapted to receive the tube on the
sheath. Then, by arranging in a proper position the key or other device for opening
and closing the dark-slide, we are enabled to insert the sheath in the tubes on the top
or side of the camera in a plane parallel thereto and then, by turning the said sheath
about the axis of its tube, the opening of the sheath will be effected, and the slots in
the tubes brought into line with each other, thus permitting the plate to fall into the
When the plate has been thus transferred to the camera, the sheath may be
camera.

page_text: turned back so as to lie parallel with the top and therefore out of the way, or, when
in this position, it may be altogether withdrawn, the slot in the camera, when the
inner tube is in this position, being closed by the said inner tube.
We sometimes provide the camera with means for attaching a dark-slide to the top
thereof and another dark-slide to the bottom thereof, one for the insertion of the
unexposed plates into the camera, and the other for the reception of the exposed plates
froin the camera. We can employ with a camera any desired number of interchange-
able dark-slides constructed as above described.
If desired we provide means whereby the sliding of the tube on the sheath
into the tube or socket on the camera will effect the opening of the dark-slide.
We sometimes employ a slotted tube or socket similar to that above described in
combination with a dark-slide of ordinary construction (or with a receptacle similarly
used) so that plates or films may be inserted therein and removed therefrom by
means of our improved dark-slide without risk of exposure of the said plates to
light.
Our improved dark-slide is constructed to contain a single plate or is adapted to
contain and successively deliver more than one plate. In the latter case, the dark-
slide is provided with grooves or other devices for keeping the plates apart and is made
reversible in the tube or socket on the camera.
We sometimes provide for facilitating the removal of the camera from a tripod for
the purpose of inverting the camera to change plates by means of our improved
dark-slide and for permitting the removal and replacement of the camera without
risk of altering a position already secured by the tripod. For this purpose, we
provide on the underside of the camera a projection or block of wood or metal having
parallel sides. This projection fits into a suitable groove or opening in the tripod-
head, or preferably in a turntable which is attached to the tripod-head, capable of
being partially closed so as to tightly clamp the said projection. The closing of
the sides of the groove against the said projection may be accomplished by means
of a spring, screw, cam or eccentric or otherwise.
Our improved shutter for effecting exposures of short duration comprises two
plates or pieces of metal or other suitable material each having its inner end
V-shaped and its outer end provided with a projecting pin or stud. These pins or
studs slide in cam-grooves formed in a disc of ebonite or other suitable material,
acted upon by a spring whereby it is partially rotated to open and close the
shutter.
If the shutter is applied to a lens of the doublet or rectilinear type, the slides
are preferably arranged to operate between the lenses, the mount of the lens being
cut or divided for the purpose of admitting them. When the shutter is closed, the
V-shaped ends overlap each other, and, when the shutter is opened so far as just to
admit light through the lens, the aperture thus formed should be central in respect to
the lens. These V-shaped shutters slide easily over one another in grooves, and, on
being operated, they first of all recede from one another until the maximum aperture
is given to the lens and afterwards approach each other until the aperture is closed. The
aforesaid grooved disc is preferably fitted to turn on the mount of the lens. A catch
with a trigger forms a convenient means for releasing the spring for operating the
shutter. A suitable device is provided for winding up the said spring. We prefer to
use, for this purpose, a ring or annular piece fitted to turn in a box or case enclosing
the said disc. The duration of the exposure may be regulated by winding up the
spring more or less as may be required.
Dated this 27th day of March 1889
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements relating to Photographic Cameras and to Apparatus
for use in connection therewith.
We, WILLIAM HENRY SMITH, of Upton Villa, Beckenham Road, in the County of
Kent, Engineer, and WILLIAM WILLIS, of Bromley, in the County of Kent,
Manufacturer, 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 :-
Our invention relates to photographic apparatus and one of its objects is to provide
improved means whereby sensitized plates or films may be conveniently transported
and may at any time be inserted in and removed from the camera without liability to
accidental exposure of the said plates or films to the action of light.
For this purpose we construct a sheath, case or dark-slide to fit into a suitable
socket on the camera, and we provide means whereby when the said dark-slide is
properly applied to the camera, the opening of the said dark-slide and the transference
of the plate or film therefrom into the camera can be effected by simply turning the
said dark-slide through an angle of ninety degrees or through any other suitable
angle.
Another object of our said invention is to provide an improved shutter for facilitating
exposures of short duration, and means for regulating the duration of the exposure.
In the accompanying drawings we have shown how our said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a side elevation of a camera having our improved dark-slide or holder
attached thereto, the parts being shown in the positions which they occupy when one
of the sensitive plates has been transferred from the said holder into the camera.
Figure 1 shows a portion of my apparatus, the dark-slide or holder being removed
and the camera shown in section.
Figure 2 is a vertical longitudinal section, illustrating the construction of our dark-
slide or holder and the means for attaching it to the camera; this and the following
Figures are drawn to an enlarged scale.
Figure 3 is a side elevation, showing the dark-slide or holder in its horizontal
position.
Figure 4 is a rear elevation, partly in section, of the said dark-slide or holder, the
plug or closing device hereinafter described being removed, and
Figure 5 is a plan of the said dark-slide, partly in horizontal section, showing the
said plug or closing device in place.
Figure 6 is a front elevation, partly in vertical section.
Figure 7 a slide elevation, and
Figure 8 a vertical longitudinal section, illustrating another form or modification of
our improved apparatus, Figures 6 and 8 showing the dark-slide in its vertical position,
and Figure 7 showing the said dark-slide in its horizontal position.
Figure 9 is a front elevation of our improved shutter for facilitating exposures of
short duration.
Figure 10 is a similar view, the outer casing being removed.
Figure 11 is a similar view, the said casing and the disc or annular piece hereinafter
described being removed.
Figure 12 is a side elevation of the said disc or annular piece.
Figure 13 is a section on the line x, x, Figure 9, and
Figure 14 is a sectional view, illustrating details of construction.
Like letters indicate corresponding parts throughout the drawings.
A is the camera, which consists of an outer box or case A and an inner sliding box
or case A. The outer case A may be provided with suitable doors A². B is the
casing or mounting containing the lenses, which is secured in any convenient manner
to the inner box or case A¹. C, C are the sensitized plates or films.
a is our sheath, dark-slide or holder, which is preferably formed of sheet-metal, and

page_text: which has, at its lower and open extremity, a metal or other tube b provided with two
longitudinal slots exactly opposite to each other, the body of the said dark-slide or
holder being soldered or otherwise secured in one of the said slots. Through these
slots, the sensitized plates or films C may be inserted into, or removed from the said
dark-slide or holder. a', a¹ are projecting strips or guides provided in the said dark-
slide or holder, for separating the sensitized plates or films therein. The dark-slide
or holder shown in the drawings is arranged to hold two of the said plates or films.
c is a plug or closing device formed of metal, wood, vulcanite or other suitable
material, and fitted into the tube so that, whilst capable of turning freely therein,
it will exclude light from the dark-slide or holder. A part of the plug or closing
device c is cut away, as shown more clearly in Figures 2 and 5, so that the said plug
is semi-cylindrical except for a short distance at either end, where it is cylindrical.
It will be seen that, by turning the said plug or shutter e in the tube b until it is
brought to the position shown in Figure 2, one of the divisions or compartments of
the dark-slide or holder a may be opened to permit the insertion of the plate or film
into, or its removal from the said compartment. By turning the said plug or shutter
through an angle of 180 degrees from the position shown in Figure 2, the other
compartment of the said holder may be opened. When the parts are in the position
shown in Figures 3 and 5, the mouth or aperture of the dark-slide or holder is
completely closed, so as to effectually exclude light.
The dark-slide or holder is secured to the outer box or case A of the camera by
means of a metal or other tube or socket d firmly secured in any suitable manner to
the said box or case A. A slot is provided in one end of the said tube or socket d,
to permit the insertion of the dark-slide or holder into the said socket from one side
of the camera, while the said holder is held horizontally; and the said socket d is cut
away as shown at d² to permit the turning of the said holder from, the horizontal to
the vertical position after it has been inserted in the said socket.
A slot A is provided in the box or case A of corresponding dimensions to the
slot in the tube b. Inside the tube or socket is provided a movable tube or
sleeve e, preferably formed thinner than the tube or socket d, and provided with
slots e of the same dimensions as the slots 1, A³. One of these slots is open at the
end next the slot d' in the socket d, to permit the insertion of the tube & therein and
its withdrawal therefrom, and the tube or sleeve e is arranged to turn with the dark-
slide or holder a when the latter is raised into the vertical position shown in Figures 1
and 2, or is folded down as shown in dotted lines in Figure 1 and in full lines in
Figure 3.
is a plate which is pivoted to the box or case A, and which can be turned up over
one end of the tube or socket d to keep the dark-slide or holder in position therein.
g is a catch or stop for limiting the movement of the dark-slide or holder when the
latter is raised into its vertical position.
We provide suitable means for turning the plug c to open one or the other
compartment of the said dark-slide or holder when the latter is in its vertical or raised
position, so that the plate or film will be delivered from the said holder into the
camera. For instance, we form in the extremities of the plug or shutter c slots or
notches c¹, and we secure to one side of the camera a bent plate or key h, which
projects into the socket d and is adapted to enter one or the other of the slots & when
the said dark-slide or holder is placed in the socket d. When the said dark-slide or
holder is raised into the vertical position, the plug e will be. held by the said catch h
and prevented from turning, and the tube will consequently assume the position
shown in Figure 2 relatively to the said plug, thus permitting one of the sensitized
plates or films C to drop into the camera.
i, i are guides for holding the plate or film in position in the camera. j, j are
springs provided upon the door A³ of the camera for retaining the plate or film
firmly in position against the said guides i.
The improved dark-slide above described is used in the following manner, viz. :-
The plug c is turned in the tube by means of a suitable key, to permit the insertion
of a plate or film in one compartiment of the said dark-slide, and, when this plate or

page_text: film has been inserted, the said plug is turned to permit the charging of the other
compartment. When the dark-slide is thus charged, its tube b is introduced into the
tube e and tube or socket d through one end thereof, the dark-slide being held
horizontally or parallel with the top of the camera for this purpose. The bent plate
or key enters the notch c¹ of the plug when the tube b is pushed home in the tube
or socket d. The dark-slide is then turned about the axis of its tube into a vertical
position, whilst the plug or shutter c is held by the key h, thus permitting one of the
plates or films C to drop into the camera. After the exposure, the said plate or film
can be returned to the dark-slide or holder by inverting or turning over the box or
case A. By folding or turning down the dark-slide or holder a on the camera, the
tube will be turned in the reverse direction relatively to the plug or shutter c, so
as to close the mouth or aperture of the dark-slide. By removing the said dark-slide
or holder, reversing it, and reinserting it in the tube or sleeve e and tube or socket d
and repeating the above described operations, the other or second sensitized plate or
film Cmay be delivered to, and removed from the box or case A. in like manner.
Any number of these dark-slides or holders may be employed, each of the same being
adapted to fit the tube or sleeve e; and the sensitized plates or films C may be
securely kept in the said dark-slide until it is desired to use them, or, when used.
until it may be convenient to develop the pictures thereon. When the dark-slide or
holder a is removed from the tube or sleeve e, the latter will occupy such a position in
the socket as to completely close the slot A³ in the box or case A, as shown in
Figure 1, and thus exclude light from the camera.
Suitable packing may be provided at e² to form a tight joint between the sleeve e
and the box or case A.
Figures 6, 7 and 8 show another modification of our invention wherein the sheath,
dark-slide or holder a extends through one side and into the other side of the tube b,
and the outer tube e is cut away as shown in Figure & to permit the required turning
movement of the tube therein to open and close the aperture of the dark-slide or
holder a.
The extremities of the tube e are closed by means of plates or discs e¹ and
are provided with slots e³ and recesses et in which are adapted to engage projections /', ²
upon catches pivoted at 3 to the sides of the box or casc A., are springs for
retaining the said catches in engagement with the said notches and recesses. When
the said dark-slide or holder is raised or moved into the vertical position shown in
Figure 8, the outer tube is held by the above mentioned catches h and the inner tube b
is rotated in the said outer tube so as to bring the open extremity of one compartment
of the dark-slide or holder over the cut away portion of the outer tube e and thus
permit the plate or film contained in the said compartment to fall through the slot A³
into the camera. By pressing inward the lower extremities of the said catches / so
as to move the other extremities thereof outward sufficiently to disengage the
projections, 2 from the said notches e and recesses et, the dark-slide or holder a
can be very readily removed from the camera. By removing the said dark-slide or
holder, reversing it and replacing it between the said catches h, the other or remaining
plate or film may be delivered in like manner into the camera.
It will be seen that, in this arrangement, the tube e serves as the shutter or closing
device in place of the plug c above-described, and the tube or socket on the camera
is dispensed with, the construction of the apparatus is therefore simplified. The
entire length of the dark-slide or holder a is reduced, because the body of the said
holder which receives the plates or films, lies partly within the tube b. Moreover the
strength of the said dark-slide or holder is increased and the said holder can be more
readily connected with the box or case A or disconnected therefrom.
Dark-slides or holders constructed as hereinbefore described are very compact, and,
by placing them one above another with their tubes & alternately at either side, they
can be very closely packed, so that a large number of the said dark-slides or holders
may be contained in a comparatively small space. Our improved dark-slide is,
moreover, inexpensive to manufacture."
In Figures 9 to 14 we have illustrated our improved instantaneous shutter. This
shutter comprises two plates or slides k formed of ebonite, metal or other suitable

page_text: material, and arranged to slide freely one in front of the other in grooves or
guides provided upon the lens-mounting or casing B. The said plates or slides
extend through slots provided in the lens-tube B' so that they can overlap one another
and close the exposure aperture of the camera. The adjacent ends of the said plates
or shutters are V-shaped or otherwise suitably formed so that, when the said plates
are moved outward to the full extent of their movement, there will be a square or
other suitable aperture between them.
The
At the outer end of each of the said plates or shutters k is provided a pin or stud k¹.
These pins or studs k¹ are arranged to slide in eccentric or cam grooves 1 formed in
the rear side of an annular piece or disc m formed of ebonite, metal or other suitable
material, and fitted to rotate upon the tube B¹ of the lens-casing or mounting. n is a
coiled spring which is arranged in a recess m* in the annular piece or disc m.
outer extremity of the said spring n is secured to the said annular piece or disc and
the inner extremity thereof to the said tube B'; o is a lever or catch pivoted at o' to
the lens-mounting or casing B, and adapted to engage in either of two notches m³, m²
in the edge of the disc m. o is a spring for retaining the said catch in engagement
with the said disc. The annular piece or disc m is provided with a handle p which
extends through and moves in a slot B2 in the lens-mounting or casing B, and
whereby the said disc may be turned about its axis to set or adjust the plates or
shutters k. When the annular piece or disc m is turned by means of the handle p in
the direction indicated by the arrows in Figures 9 and 11, the spring n is compressed
or wound пр
and the plates or shutters k, which normally close the aperture of the
lens-tube B, are moved by the action of the cam-grooves so as to first open the said
aperture and admit light through the lens or lenses, and then close the said aperture.
When the catch o is engaged in the notch m¹ as shown in the drawing, the said
aperture is open, and may be closed by turning the disc m in the direction indicated
by the arrows until the catch o engages in the notch m². Upon releasing or
disengaging the catch o, the shutters will be operated by the spring, and thereby
caused to more or less rapidly open and close the aperture.
To provide for regulating the speed with which the annular piece or disc m revolves
under the action of the spring n, we employ a suitable brake comprising a spindle
the screw-threaded portion of which is fitted into a correspondingly screw-threaded
nut or plate secured to the lens-mounting or casing B. The extremity of the said
spindle bears against a springs (Figure 14) which is attached to the casing B and
which, in its turn, bears against an inclined surface m³ (Figures 12 and 14) upon the
said annular piece or disc m. A stop m is, moreover, provided for limiting the
movement of the said disc m and preventing any jar or shock by the sudden impact
of the handle p against the extremity of the slot B2 when the said disc is rotated under
the action of the spring n to operate the plates or shutters k. By screwing the said
spindle g further into, or unscrewing it from the nut r, the said springs may be
caused to exert greater or less pressure against the inclined surface m³ and thus retard
more or less the motion of the annular piece or disc m. t is a graduated scale provided
upon the plate or nut r, and is a pointer fixed to the spindle y for indicating the
amount of pressure exerted upon the said annular disc m, and consequently the length
of the exposure that will be given by the plates or shutters k, in any given position of
the spindle q.
P
(Figure 1) is a trigger, which can be conveniently operated from the exterior of
the box or case A of the camera, so as to release the catch o from the notch m² or m².
is a milled handle whereby the inner box or case A' may be caused to slide to
and fro for a certain distance in the outer box or case A, to obtain the proper focal
adjustment, and whereby the said inner box may be clamped securely in any desired
position. This movement of the inner box is regulated by the length of the slot w in
the outer box or case A, through which the spindle of the said handle passes. The
said spindle is screw-threaded and fits into a correspondingly screw-threaded nut or
plate provided upon the inner box or case A'.
The above described plates or shutters k, when employed with lenses of the doublet
or rectilinear type, may be arranged to operate between the lenses as shown.

page_text: It is obvious that we can somewhat modify the construction of our apparatus
without departing from the nature of our said invention. For instance we sometimes
provide means whereby the act of sliding the tube of the dark-slide or holder into the
tube, sleeve or socket on the camera will effect the opening of the said dark-slide or
holder.
We sometimes combine, with a dark-slide or holder of ordinary or other con-
struction, or with a cell-bath or other receptacle in which sensitized plates or films
may be developed, fixed, dried, stored or otherwise treated, means substantially as
above described whereby our improved dark-slide or holder may be readily attached
thereto, so that the sensitized plates or films may be inserted therein and removed
therefrom without risk of exposure of the said plates or films to the light.
Our improved dark-slide or holder may be constructed to contain and deliver any
desired number of sensitized plates or films, suitable grooves, guides or other devices
being provided for keeping the said plates apart.
We sometimes provide the camera with means for attaching one of our improved
dark-slides or holders to the top thereof and another of the said dark-slides or
holders to the bottom thereof, one for the insertion of the unexposed plates into
the camera and the other for the reception of the exposed plates from the camera.
It is obvious that, if desired, the plug or shutter of the dark-slide, sheath or holder
can be arranged to be turned by means of a separate key to permit the plate or film
to fall from the said dark-slide or holder into the camera, cell-bath or other receptacle.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we wish it understood
that we claim :-
First. The above described method of providing for the opening and closing of
a dark-slide, sheath or holder for photographic plates or films, by the turning of the
same through a predetermined angle when applied to a camera, a cell-bath or other
photographic receptacle, for the purposes specified.
Second. A dark slide, sheath or holder for photographic plates or films, provided
with a plug or shutter which, when the dark-slide or holder is applied to a camera, a
cell-bath or other photographic receptacle, will engage with a suitable key thereon so
that the turning of the dark-slide or holder through a predetermined angle relatively
to the said camera or other receptacle will effect the opening and closing of the said
dark-slide, for the purposes above specified.
Third. A dark-slide sheath or holder provided with a slotted tube and with a plug,
shutter or closing device fitted therein so that it can be rotated about its axis and so
constructed that, in its rotation, it will open and close the aperture of the said dark-
slide or holder, substantially as, and for the purposes, set forth.
Fourth. A camera, cell-bath or other photographic receptacle provided with a slot
and with means for retaining our improved dark-slide, sheath or holder in place over
the said slot whilst permitting its rotation about the axis of its tube or socket, sub-
stantially as, and for the purpose, above specified.
Fifth. The combination, with a camera, cell-bath or other photographic receptacle,
of devices for retaining our improved dark-slide, sheath or holder over the slot
through which the plates or films are introduced, and for preventing rotation of
the plug or shutter of the said dark-slide, sheath or holder relatively to the said
camera or other receptacle, whilst permitting rotation of the said plug or shutter and
dark-slide sheath or holder relatively to each other, substantially as, and for the
purpose, above specified.
Sixth. The combination of a dark-slide, sheath or holder provided with a tube and
with a plug, shutter or closing device fitted to turn about its axis in the said tube, and
a camera, cell-bath, or other photographic receptacle provided with means for
retaining or securing the said dark-slide, sheath or holder in place above the slot
therein, and for preventing rotation of the plug, shutter or closing device whilst
perinitting the rotation of the dark-slide, sheath or holder relatively to the said camera
or other receptacle, substantially as, and for the purposes, set forth.

page_text: Seventh. The improved dark-slide, sheath or holder constructed substantially as
described with reference to Figures 1, 1ª, 2, 3, 4 and 5, or with reference to
Figures 6, 7 and 8 of the drawings, and operating as, and for the purposes, above
specified.
Eighth. The improved devices constructed substantially as described with reference
to Figures 1 to 5, or with reference to Figures 6, 7 and 8 of the drawings, whereby
we provide for securing our improved dark-slide, sheath or holder upon a camera,
cell-bath or other photographic receptacle, and for automatically opening and closing
the said dark-slide, sheath or holder when the latter is turned from a horizontal to a
vertical position and vice versa, as above specified.
ن
Ninth. A photographic instantaneous shutter comprising two plates or slides
arranged to be moved towards and away from each other by means of pins or studs,
working in eccentric or cam grooves in a disc arranged to revolve about the centre or
axis of the lens-tube, substantially as described.
Tenth. The combination, with the annular piece or disc for operating the slides or
shutters, of suitable micans for varying the velocity of movement of the said disc and
slides or shutters and thus regulating the duration of the exposure, substantially as,
and for the purpose, above specified.
Eleventh. The improved photographic shutter constructed substantially as described
with reference to Figures 9 to 14 of the drawings, and operating as above specified.
Twelfth. The improved photographic camera provided with our dark-slide or
holder and instantaneous shutter, all constructed and combined substantially as
described with reference to the accompanying drawings.
Dated this 21st day of January 1890.
.
W. H. SMITH.
W. WILLIS.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicants.