IMPROVEMENTS IN THE CONSTRUCTION OF STEREOSCOPES
Year: 1859

page_text: LETTERS PATENT to James Wansbrough, of Bridge Street, in the Borough
of Southwark, Gentleman, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF STEREOSCOPES."-A communication from abroad by Egbert.
Moxham, of Bruges, in the Kingdom of Belgium.
Sealed the 29th November 1859, and dated the 31st May 1859.
PROVISIONAL SPECIFICATION left by the said James Wansbrough at
the Office of the Commissioners of Patents, with his Petition, on
the 31st May 1859.
I, JAMES WANSBROUGH, of Bridge Street, in the Borough of Southwark,.
Gentleman, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE CONSTRUCTION OF STEREOSCOPES," to be as follows:-
This Invention relates to a mode of rectifying in the stereoscope the dis-
tortion which is common to photographs of architectural subjects, and which
arises from the camera used in taking the picture being set at an incline,. in.
order to take in the upper portion of the view. By thus setting the plane of
the lenses at an angle to the plane of the view, the photograph of a street,
for example, gives the lines of buildings the appearance of falling forwards.
The like defect is also painfully apparent in photographs of the interior of
cathedrals or other lofty buildings. To remedy this defect when viewing such

page_text: pictures stereoscopically, it is now proposed to place the pictures in the
stereoscope so that the plane of the lenses and the plane of the pictures shall
(instead of being, as heretofore, parallel) be at an angle to each other. This
change of position of the pictures will wholly or in great part neutralize the
want of parallelism in the vertical lines, and thereby restore the truthfulness
of the representation. The simplest manner of effecting this improvement is
to attach the bottom of the stereoscope to the case by a hinge joint or pivots,
which will permit of its being adjusted to any angle of inclination to suit the
architectural pictures under view, and also allow of its being restored to its
customary position when another class of pictures is required to be viewed in
the stereoscope.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Wansbrough in the Great Seal Patent Office on
the 30th November 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
WANSBROUGH, of Bridge Street, in the Borough of Southwark, Gentleman,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of May, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said James Wansbrough, Her special license that I, the said James Wans-
brough, my executors, administrators, and assigns, or such others as I, the
said James Wansbrough, my executors, administrators, and 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 "IMPROVE-
'MENTS IN THE CONSTRUCTION OF STEREOSCOPES," being a communication from
abroad by Egbert Moxham, of Bruges, in the Kingdom of Belgium, upon
the condition (amongst others) that I, the said James Wansbrough, 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 inmediately after
the date of the said Letters Patent.

page_text: NOW KNOW YE, that I, the said James Wansbrough, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the follow-
ing statement, reference being had to the Drawing hereunto annexed, and
to the letters and figures marked thereon (that is to say) :-
This Invention, as communicated to me from abroad, relates to a mode of
rectifying in the stereoscope the distortion which is common to photographs
of architectural subjects, and which arises from the camera used in taking
such pictures being set at an incline, in order to take in the upper portion of
the view. The effect of thus setting the camera at an angle to the plane of
the view is to impart to the photographic representation of a street, for
example, the appearance of the rows of buildings falling forwards, the vertical
lines being at the same time elongated or thrown out of proportion. The
same defect is also painfully apparent in photographic views of the interior
of cathedrals or other lofty buildings, the width between the walls. or columns
contracting from the floor upwards. To remedy this defect when viewing
such pictures stereoscopically, it is now proposed to construct the stereoscope
so that the plane of the pictures instead of being, as heretofore, at right
angles to the axis of vision, may be adjusted at an inclination thereto. This
change of position of the pictures will be found wholly or in great part to
neutralize the want of parallelism in the vertical lines, and thereby restore
the truthfullness of the representation.
In the accompanying Drawing I have shewn a partial longitudinal section
at Fig. 1, and an underneath view at Fig. 2, of a stereoscope fitted according
to this Invention, that is, with an adjustable frame or bottom for holding the
pictures at an inclination to the axis of vision. It will be obvious that this
principle of construction may be carried out in various ways, but that pre-
ferred by the Inventor, as the simplest for neutralizing the defects above
noticed in photographic pictures, is the arrangement shewn in the Drawing.
a, a, is a stereoscope case of the ordinary construction, and fitted as usual
with lenses for magnifying the pictures. The open or closed frame c of the
case, instead of being made a fixture, is connected to the case by hinges. To
ensure its retaining the inclined position to which it may be adjusted, the
free end of the frame is provided with a spring catch d, which, bearing upon
the case a, will retain the frame c in position by friction of contact. A metal
stop e, secured to the case a, will, by limiting the range of movement of the
spring catch d, prevent the frame from swinging loose on its hinges. This
arrangement, it will be seen, will allow for the setting of the stereoscopic
pictures to any required angle of inclination, which will vary according to the

page_text: degree of distortion visible in the pictures under inspection, the optical law
on which this adjustment is based being that the apparent size of an object
diminishes in proportion as its recedes from the eye, or as its distance from the
eye of the observer is increased. By thus fitting the frame c to the case a, it
may be readily restored to its customary position when another class of pictures
is required to be viewed in the stereoscope. In place of hinges for jointing
the frame to the case, pivots may be substituted, when the frame will be free
to swing like a looking-glass in its stand. This will also make a very good
⚫ arrangement.
Having now set forth the nature of this Invention of "Improvements in
the Construction of Stereoscopes," as communicated to me by my. corre-
spondent, and explained the manner of carrying the same into effect, I wish
it to be understood that I claim the application to stereoscopes of the adjustable
frame or support for the pictures for the purpose above described.
In witness whereof, I, the said James Wansbrough, have hereunto set
my hand and seal, the Thirtieth day of November, in the year of
our Lord One thousand eight hundred and fifty-nine.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
JAMES WANSBROUGH. (L.S.)