Improvements in Detective or Hand Cameras.
Year: 1890

page_text: ate of Application, 4th Mar., 1890
Complete Specification Left, 4th Dec., 1890-Accepted, 16th Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements in Detective or Hand Cameras.
I WALTER GRIFFITHS of Highgate Square Birmingham in the County of Worcester
Manufacturer do hereby declare the nature of my said invention to be as follows:--
:
My invention has for its object a new or improved detective or band camera by
which I provide a thoroughly efficient & trustworthy camera with all the necessary
accessories complete, much more cheaply & economically than has been done hitherto
& which will allow such a camera to be sold at about one quarter the cost of present
cameras of equal capabilities & power.
In carrying my invention into effect I form the box, case, or cover of the camera
of mill-board straw-board or other similar material which I preferably bind or cover
with American cloth & strengthen where required by wood or other stiffeners. This
case is provided with a top lid which is hinged upon a cloth or other similar hinge,
& fastened by a strap arrangement or other suitable contrivance. The front end of
this case which is provided with the necessary aperture opposite the lens, is also
made to hinge, so as to gain ready access to the shutter mechanism afterwards to be
described, & upon the top lid or from any other convenient part I provide a handle
by which the camera would be held or carried by the hand. Within a portion of this
case form the camera with mill-board sides & strengthened at back with wooden
stiffeners, the front being formed of wood & having the lens attached to the internal
side of the wood & the shutter frame to the external side, the hole in the shutter frame
being made to form the stop for the light and the wooden division being of the
necessary thickness to form the correct distance from the lens on the inside to the
stop hole in the shutter frame on the outside & thus by placing the lens inside, &
the shutter outside I am enabled to expose & cut off the light at the most concentrated
point .e. at the stop in a simple, very cheap & effective manner. The rebounding
shutter & frame used is of an ordinary type consisting of a thin metal frame turned
over at the edges to form grooves in which the ebonite shutter slides. A piece of elastic
is attached to the upper part of the frame & attached to the shutter when closed over
the aperture where it is held by a catch provided for the purpose but upon the shutter
being released, it is rapidly shot up by the elastic from which it is thereby disengaged
after which it rebounds against a similar length of elastic to its former position over
the aperture in the frame.
An opening is provided in the bottom of the outside cover to allow the fingers to
act in operating the catch which releases the shutter.
My camera is arranged so as to take negatives of lantern slide size but the dark
slides to be hereafter described are arranged to receive quarter plate size which is
usually the most convenient size to be obtained & thus lantern slides may be printed
by contact with the negatives taken in my camera.
Another portion of my improvement consists of the dark slides each of which are
formed of strong mill straw or other such board & are each made to contain two
plates & consist of three leaves which are bound together by cloth to open in a
similar way to a book each of the two outside leaves of which are composed of three
pieces of mill-card or other similar board sprigged, tacked or otherwise fastened
together the inside piece having an aperture cut out large enough to receive a quarter
plate & the mill-board being thick enough for the plate to be contained within the
thickness flush & the centre & outer pieces which are of somewhat thinner proportions
& are provided with an aperture of the size of a lantern slide between which two
pieces the dark slide shutter (which consists of thin metal) slides the shutter being
provided with a curl in the metal at the top for convenience in withdrawing.
Between these two outside leaves I provide the centre mill-board leaf having

page_text: attached to it on each side a spring which presses against the plates & keeps them
firmly in position the leaves being tightly retained together when in use by means
of a metal clip of the shape of the three sides of the book, which slides on &
embraces the edges of the two stiff pieces of mill-board within the thickness of
which the plates are contained at the same time effectually excluding any light
which might otherwise penetrate between the leaves. A number of these dark slides
may be provided to each camera & their position may readily be fixed in the first
instance when the camera is being made by means of a wooden frame made' tem-
porally movable against which they butt & which may be moved until the plate is in
focus after which the frame is permanently fixed so that the dark slides are always
pressed against it in the same position by springs which are provided in the body of
the outer casing.
A velvet surface between the dark slide & this frame prevents any light entering
as also a velvet surface is provided upon the two surfaces between which the dark slide
shutters slide.
I provide a finder consisting of the ordinary concave lens & mirror, but for
cheapness & ease in using I mount them in a folding or collapsible frame of cloth
leather or suitable material & attach the same to any convenient portion of my outside
covering so that upon opening the purse shaped frame the lens & mirror will
occupy the proper position with regard to the camera to illustrate the view upon the
plate.
The finder would be fastened when closed & open by any convenient arrangement
of strap, tape, buttons or similar contrivance.
I do not confine myself to the exact details here described as I may use my other
improvements in combination with a casing made of metal or other material but as a
rule I prefer to use them in a similar manner to that herein described.
Dated 3rd day of March 1890.
WALTER GRIFFITHS.
COMPLETE SPECIFICATION.
Improvements in Detective or Hand Cameras.
I WALTER GRIFFITHS of Highgate Square Birmingham in the County of Worcester
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 :-
My invention has for its object improvements in detective or hand cameras by
which I provide a thoroughly efficient & trustworthy camera with all the necessary
accessories complete much more cheaply and economically than has been done hereto-
fore & which will allow such a camera to be sold at about one quarter the cost of
present cameras of equal capabilities and power.
In carrying my invention into effect, I form the box, case, or cover of the camera
of mill-board, straw-board, or other similar material which I preferably bind or cover
with American cloth & strengthen where required by wood, or other stiffeners.
This case is provided with a top lid which is hinged upon a cloth or other similar
hinge & fastened by a strap arrangement or other suitable contrivance. The front
end of this case which is provided with the necessary aperture opposite the lens is
also made to hinge so as to gain ready access to the shutter mechanism afterwards to
be described. Upon the top lid or from any other convenient part I provide a handle
by which the camera would be held or carried by the hand. Within a portion of this
case I form the camera with mill-board sides & strengthened at back with wooden
stiffeners, the front being formed of wood and having the lens attached to the internal
side of the wood & the shutter frame to the external side, the hole in the shutter frame
being made to form the stop for the lens, the wooden division being of the necessary
thickness to form the correct distance from the lens on the inside to the stop hole in
the shutter frame on the outside & thus by placing the lens inside & the shutter outside

page_text: I am enabled to expose & cut off the light at the most concentrated point i.e. at the
stop, in a simple very cheap and effective manner.
.
The rebounding shutter & frame used is of an ordinary type consisting of a thin
metal frame turned over at the edges to form grooves in which the ebonite shutter
slides, a piece of elastic is attached to the upper part of the frane and attached to
the shutter when closed where it is held over the aperture by a catch provided for the
purpose but upon the shutter being released it is rapidly shot up by the elastic which
is thereby disengaged after which it rebounds against a similar length of elastic to its
former position over the aperture in the frame. An opening is provided in the
bottom of the outside cover to allow the fingers to act in operating the catch which
releases the shutter. My camera is arranged so as to take negatives of lantern slide
size but the dark slides to be hereafter described are arranged to receive quarter plate
size which is usually the most convenient size to be obtained & thus lantern slides may
be printed by contact with the negatives taken in my camera.
Another portion of my improvement consists of the dark slides each of which are
formed of strong mill straw or other such board & are made to contain two plates
and consist of three leaves which are bound together by cloth to open in a similar way
to a book each of the two outside leaves of which are composed of three pieces of
mill card or other similar board sprigged together the inside piece having an aperture
cut out large enough to receive a quarter plate & the mill-board being thick enough
for the plate to be contained within the thickness flush and the centre & outer pieces
which are of somewhat thinner proportions and are provided with an aperture of the
size of a lantern slide & between which two the dark slide shutter which consists of
thin metal slides the shutter being provided with a curl in the metal at the top for
convenience in withdrawing. Between these two outside laves I provide the centre
mill-board leaf having attached to it on each side a spring which presses against the
plates and keeps them firmly in position the leaves being tightly retained together
when in use by means of a metal clip of the shape of the three sides of the book which
slides on & embraces the edges of the two stiff pieces of mill-board within the
thickness of which the plates are contained at the same time effectually excluding any
light which might otherwise penetrate between the leaves.
A number of these dark slides may be provided to each camera and their position
may readily be fixed in the first instance when the camera is being made by means of
a wooden frame made temporally moveable against which they butt & which may be
moved until the plate is in focus after which the frame is permanently fixed so that
the dark slides are always pressed against it in the same position by springs which are
provided in the body of the outer casing.
A velvet surface between the dark slide & this frame prevents any light entering
as also a velvet surface is provided upon the two surfaces between which the dark
slide shutters slide.
I may provide a finder consisting of the ordinary concave lens & mirror but for
cheapness and ease in using & mount them in a folding or collapsible frame of clotb
leather or suitable material and attach the same to any convenient portion of my
outside covering so that upon opening the purse shaped frame the lens & mirror wil!
occupy the proper position with regard to the camera to illustrate the view upon the
plate. The finder would be fastened when closed & open by any convenient arrange-
ment of strap, tape, buttons or similar contrivance.
I do not confine myself to the exact details as here described as I may use my other
improvements in combination with a casing made of metal or other material but as a
rule I prefer to use them in a similar manner to that herein described.
In order that my invention may be clearly understood and more easily carried into
practice I have appended hereunto two large sized sheets of drawings upon which I
have fully illustrated the nature of my said improvements.
Figure 1 is a general view of my detective or hand camera with lid & end open.
Figure 2 is a view of the same camera when closed.
Figure 3 is another view of the camera when closed but in this case looking up to
shew the means for operating the shutter.

page_text: Figure 4 is a view of the dark slide shewn open ready for the insertion of the
sensitized plates.
Figure 5 is a view of the metal clip for binding the leaves of the dark slide
together.
Figure 6 is a vertical section through one of the dark slides.
Figure 7 is a vertical section through the back part of the camera on line 1—2.
Figure 8 is an elevation of the shutter & stop arrangement and
Figure 9 is a vertical section through same.
The box case or cover A of the camera is formed of mill-board straw-board or other
similar material which is preferably bound or covered with American or other similar
cloth and strengthened where required by the wood or other stiffeners a¹. A suitable
lid A2 is provided and hinged to the body A in any suitable manner & is secured
down by the catches a³ or other such arrangement. The front end A¹ of the case A
is provided with the necessary aperture a opposite the lens B' and is hinged at a so
as to gain ready access to the shutter mechanism for the purpose of setting for
exposure. Upon the lid A² or other convenient position the handle a' is formed so as
to enable them to be conveniently held or carried by hand.
Within the body or case A the camera B is placed being formed with mill-board
sides and strengthened at the rear with the stiffeners 62 and at the front with the wood
stiffening partition 13 to the interior side of which the lens B is attached in any
suitable manner the shutter frame 4 being fixed to the external side so that the
aperture forms the necessary stop concentric with the lens the wooden partition
being of sufficient thickness to form the correct distance between the lens B¹ on the
inside to the stop hole on the shutter frame & on the outside which allows the light
to be exposed or cut off at the most concentrated point i.e. at the stop.
The rebounding shutter 1 & frame is of the ordinary type the said frame * being
turned over at the edges to form grooves in which the ebonite or other shutter 66
slides. The shutter is operated by the elastic or other suitable spring 67 and rebounds
from that portion of the elastic or other spring 68.
The catch D is provided to retain the shutter & over the aperture the shutter being
released by pressing the end d¹ of the catch in the direction of the arrow until the
shutter is released. The opening A8 Figure 3 is provided to allow the fingers to be
inserted to operate the end of the catch.
The dark slides which are arranged to take quarter plates are each formed of strong
mill straw or other such board preferably waterproof and consists of the two outside
leaves E and F which consist respectively of two pieces of straw or other board e¹ and e²
and fand 2 with the intermediate but thinner pieces e³ and f³ each leaf being
sprigged sewn or otherwise fastened together. Apertures are cut out of the pieces el e²
and ff sufficiently large to receive a quarter plate the board being thick enough in
the case of el and for the plates to be contained flush within the thickness. The
intermediate pieces e and f3 which are somewhat thinner are provided with suitable
aperture of the size to take a lantern or quarter plate size.
Between the pieces 2 and 3 and 2 and f³ the thin metal shutters G* and_H_are
made to slide the curls g¹ and being formed for convenience of withdrawing and ou
the inside face of the top of the pieces and 3 and 2 and 3 where the shutter
passes through velvet or other pile material is provided so as to exclude the light after
the shutter is withdrawn. Between these two outer leaves E and F the centre leaf K
is provided for separating the light from the rear plate & fixed to each side of this
leaf are the small springs which fix the plates in register.
The leaves are bound together at the one end by the cloth or leather back & are
secured tightly together at their opening edges by the metal clip M the flanges m' of
which slide in the grooves m². Instead of binding the leaves at one end they may be
loose & a clip slipped on from both ends or I may hinge metal clips to the back of the
slide so as to fold up each side of the slide with a loose end clip to attach the ends
together. A number of these dark slides which are interchangeable may be provided
<for use in each or to any camera but 1 generally prefer to insert three one of which P
is placed ready for use as shewn in Figure 7 next the frame 62 against which it is

page_text: pressed by the springs N which are fixed to the stiffeners a¹ & which always retain the
slide in a fixed position & upon the frame 12 a velvet surface is formed at p² to prevent
the entrance of light. The other two dark slides are placed in the camera between the
back of the body A and the stiffeners a¹.
I may or may not use a finder neither do 1 confine myself to the kind of finder I
may use as it may be as before described or as shewn upon the drawings where the
lens R reflects the picture from the mirror on to the ground glass ².
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 :-
1st In improvements in detective or hand cameras the dark slide made and
operated; substantially as herein set forth and shewn by Figures 4, 5 and 6 on the
drawings.
2nd-In improvements in detective or hand cameras the arrangement of the
stop 65 concentric to the lens and in contact with the shutter; substantially as herein
set forth and shewn.
3rd-In the improvements in detective or hand cameras, the combination of the
mill or straw-board casing with the lens and slides, the whole operated together ;
substantially as and for the purpose herein set forth and shewn upon the accompanying
two sheets of drawings.
Dated this 3rd day of December 1890.
WALTER GRIFFITHS.