AN IMPROVED CAMERA OBSCURA
Year: 1867

page_text: LETTERS PATENT to Jean Petrzywalski, of No. 6, John Street, Adelphi,
in the County of Middlesex, Gentleman, for the Invention of "AN
IMPROVED CAMERA OBSCURA."
Sealed the 29th November 1867, and dated the 7th June 1867.
PROVISIONAL SPECIFICATION left by the said Jean Petrzywalski at the
Office of the Commissioners of Patents, with his Petition, on the
7th June 1867.
I, JEAN PETRZYWALSKI, of No. 6, John Street, Adelphi, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention
for "AN IMPROVED CAMERA OBSCURA," to be as follows:-
This apparatus consists of a square or other shaped wooden or metal box
formed of two parts, one sliding within the other so as to arrange the focus,
and forming a dark chamber, at one end of which is a sheet of ground glass,
whilst at the opposite extremity the object to be reflected thereon is placed;
at one or both sides of the object a lamp or lamps are placed, the light being
concentrated by reflectors on the object; it is reflected on the glass on an
enlarged scale by powerful lenses mounted in the usual manner and fixed in
a sliding panel in front of the lamps.
The lamp or lamps are furnished with chimneys passing through the top of
the case for carrying off the smoke and heat, and hinged doors are made in
I the box on either side of the lamps so as to admit of cleaning and trimming
the same, which may burn any kind of oil or spirit, or gas or lime light may
[Price 8d.]

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Jean Petrzywalski in the Great Seal Patent Office on the
7th December 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JEAN
PETRZYWALSKI, of No. 6, John Street, Adelphi, in the County of Middlesex,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventh day of June, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Jean Petrzywalski, Her special licence that I, the said Jean Petrzywalski,
my executors, administrators, and assigns, or such others as I, the said
Jean Petrzywalski, 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 "AN
IMPROVED CAMERA OBSCURA," upon the condition (amongst others) that I, the
said Jean Petrzywalski, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, 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 immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said Jean Petrzywalski, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement and accompanying drawings, that is to say:-
This apparatus consists of a square or other shaped wooden or metal box
formed of two parts, one sliding within the other, which facilitates the adjust-
ment of the focus and forms a dark chamber, at one end of which is a sheet of

page_text: ground glass, whilst at the opposite extremity the object to be reflected is placed;
at one, but preferably on each side of the object, a lamp is placed, a similar one
being in front thereof, the rays of the three lights being concentrated by
reflectors on the object; it is reflected on the ground glass on an enlarged
scale by powerful lenses mounted in the usual way for such purposes; and
fixed in a sliding panel in front of the lamps and object. The lamps are
furnished with chimneys passing through the case for carrying off the smoke
and heat, or a more simple and efficacious mode is to fix them outside the
case, and by this means the heat which would be engendered within the
case is obviated, and the necessity of having doors is done away with, as
herein-before mentioned as pertaining to the apparatus. The lamps may burn
any kind of spirit, gas, or lime light, but the ordinary paraffin oil will suffice
in all ordinary cases.
The apparatus which I term the "photo-megascope" reproduces with great
accuracy any kind of image, either photographic, prints, drawings, and indeed
almost any kind of object whether coloured or otherwise, magnifying them
on a scale proportionate to the size of the machine. It will therefore
readily be perceived that it can be employed successfully in enlarging photo-
graphic portraits, prints, lithographs, natural objects, living or otherwise,
and this by merely making use of the ordinary and well-known photographic
means or process, with the advantage that positives or negatives can be equally
well taken at day or night. The magnifying power being from 50 to 500
degrees it proves most useful in taking an exact fac-simile of the smallest
insects. As a photographic album it admits of the successive reproduction of
carte de visite or other portraits in a magnified form, so that a number
of people can see the picture at the same time represented on the ground
glass at the end of the apparatus. It may also be employed for conveying
signals or messages for railways or other purposes either by exhibiting signs,
rebuses, figures, or letters, or any similar means giving an equal result, the
mechanism for producing the necessary change of subject being of the simplest
nature.
Having now described the object of the Invention I will proceed to mention
the apparatus and its details by aid of the accompanying Drawings, of which
Fig. 1 is a sectional side view of the photo-megascope.
A and B are the parts as already described as sliding one within the other for
adjusting the focus; C is a conical-shaped box having four circular openings,
the smallest D supports one end of the case or tube bearing the lenses C¹,
whilst the opposite extremity is held in the sliding panel E of the chamber A;
at the opposite end to the aperture D is a larger opening F shewn by the dotted

page_text: lines; it is in front of this opening that the object F1 (to be reflected on the
ground glass G at the further extremity of the apparatus is placed), the said
opening being furnished with grooves or otherwise to facilitate the sliding in or
removal of the image or subject desired to be enlarged or magnifyed. On either
side of the cone C a lamp is placed, the tubes connecting them thereto passing
through the openings H, H; the third lamp is placed in front of the opening F.
Fig. 2 is a back end view of the machine which has a sliding panel I for
protecting the sheet of ground glass J when the apparatus is not in use. By
simply removing this panel, and substituting therefore an ordinary photographic
slide or frame containing the negative glass prepared in the usual way, the
object is obviously reflected on it instead of on the ground glass; and by the
ordinary and well-known photographic means positives or negatives can be
readily and rapidly produced in a few minutes by one single operation instead
of the three well-known ones required by the present process of photography
in enlarging a carte de visite portrait to a life-size portrait.
Fig. 3 is a front end view of the apparatus, shewing the three lamps in situ,
with their accessories. K, K, are metal cylindrical cases enclosing the lights
and protecting the glass shades L, L; M, M, are reflectors, and at the opposite
ends to these are condensers for concentrating the light. In front of the
opening F a similarly constructed lamp is placed, the three lights being so
placed and arranged that the luminous rays meet at an angle of 60 degrees.
Fig. 4 is a plan from above shewing the position of the three lamps K, K, K.
The peculiar form of the case C renders it specially applicable for the adjust-
ment of the lamps and the concentration of the whole light on one point, and
will prove most advantageous for various other purposes apart from that to
which in this instance 1 employ it. When not in use the part A will slide
into that of B, and the case C being movable can then be disconnected with
the lenses and placed in the interior; the whole then forms a square or
oblong box standing on small feet and having a handle for the convenience of
carriage.
One of the peculiar features of this Invention is that I can operate equally
well with positives or negatives on glass as with cartes de visites which are
opaque. The same letters of reference indicate like parts shewn in the several
Figures.
The object of my Invention it will be perceived from the foregoing description
and accompanying illustrations is either to reproduce on an enlarged scale
carte de visite portraits, prints, lithographs, or drawings, coloured or otherwise
or for magnifying insects, such objects being reflected on a sheet of ground
glass at the end of the apparatus; or to produce negatives and positives from

page_text: carte de visite or other portraits by simply withdrawing the sliding panel
protecting the ground glass, and in its stead inserting the photographic frame
containing the previously prepared glass or paper by the ordinary process,
the necessary light for producing the above-named result being effected by aid
of the three lamps and conical case precisely as herein set forth. The dimen-
sions of the apparatus would naturally vary to suit desire or requirements as
well as the material of which it is composed.
Having thus described my Invention, and the mode of operating the same,
what I claim and desire to secure by Letters Patent is, the general arrange-
ment of the several parts forming the apparatus as herein mentioned and
illustrated by the accompanying Drawings.
In witness whereof, I, the said Jean Petrzywalski, have hereunto set my
hand and seal, this Seventh day of December, in the year of our Lord
One thousand eight hundred and sixty-seven.
Witness,
A. C. HENDERSON,
31, Charing Cross.
JEAN FETRZIWALSKI. (L.S.)