A NEW OPTICAL INSTRUMENT WHICH I CALL A PHYSIOSCOP
Year: 1857

page_text: otection
application for Letters Patent was not given within the time prescribed
by the Act.)
PROVISIONAL SPECIFICATION left by Jean Baptiste Donas at the Office
of the Commissioners of Patents, with his Petition, on the 16th November
1857.
I, JEAN BAPTISTE DONAS, of 36, Rue de l'Echiquier, Paris, Artist in
Photography, do hereby declare the nature of the said Invention for " A
NEW OPTICAL INSTRUMENT WHICH I CALL A PHYSIOSCOP," to be as follows:-
This instrument is intended for the exhibition of stereoscopic plates, and
has the shape of a desk, the top of which, when raised, serves as a shading
reflector. The image or picture, on a glass plate, is laid at the place on the
top, and is reflected by a looking-glass which is laid at the bottom. The
images made either on paper or metallic plates are laid at the very place of
the lid of the instrument. By means of two buttons suitably disposed on the
right side, the instrument can be raised and brought to the suitable focus to
fit the sight of any person looking into it. The advantages of this instrument
over the common stereoscope are the following:-
Firstly, straightening the pictures of metallic plates which are viewed in a
reverted state.
Secondly, allowing the focus to be brought nearer to or further from the
sights of persons.
Thirdly, softening the pictures on paper, the grain of which disappears.
Fourthly, increasing twice the length of the focus by its new disposition.

page_text: Fifthly, doing away entirely with the use of unpolished glass, which is no
longer required.
Sixthly, producing hues of better appearance to the pictures viewed in it by
the effect of a shaking reflector properly disposed.
The Figures of the annexed Drawing shew two specimens of the physioscop.
Fig. 1 is a perspective view of the instrument completely closed; Fig. 2
shews it half opened; Fig. 3, with the lid entirely opened. A, A, double
magnifying viewing glasses; M, lid used as a moveable shading reflector; D, top
of the instrument covered by the lid when it is entirely shut down, when raised
the glass plate or picture is placed at D, to be looked at through tho magnifying
prismatic or lenticular glasses. A, A; B, button used to raise the outward box
carrying the picture D to bring it to the focus best suiting the sight of the
persons using the instrument; C, button used to raise the image or plate D
more or less, and to bring it to a suitable angle to agree with the distance of
tho
eyes to the bottom looking-glass.
Fig. 4 is another arrangement of the instrument made on a larger scale,
capable of receiving pictures of a larger size. Instead of the buttons B & C
for raising the viewing glasses and plate, there is a bellows-like folding box
E, E, which is drawn up by hand with some contrivance to cause it to remain
at its proper place.
If the pictures on photographic paper need not be reflected they are slided
through a narrow groove, cut out through the side near to the bottom of the
instrument, and they are laid over the looking-glass which is bidden by it.
Instead of using double-pictured plates, as in common stereoscopes for pro-
ducing a relievo-like effect, my improved instrument can be disposed for
plates with a single picture, and the bottom is then furnished with two
reflecting glasses placed at an angular position and allows the using of
larger plates, and produce the same effect.