IMPROVEMENTS IN PHOTOGRAPHIC Apparatus
Year: 1874

page_text: LETTERS PATENT to Thomas Lester, of Ossington, in the County of
Nottingham, Schoolmaster, for the Invention of "IMPROVEMENTS IN
PHOTOGRAPHIC Apparatus."
Scaled the 30th October 1874, and dated the 27th July 1874.

page_text: SPECIFICATION in pursuance of the conditions of the Letters. Patent,
filed by the said Thomas Lester in the Great Seal Patent Office
on the 23rd January 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
LESTER, of Ossington, in the County of Nottingham, Schoolmaster,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of July, in the year
of our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Thomas Lester, Her special licence
that I, the said Thomas Lester, my executors, administrators, and
assigns, or such others as I, the said Thomas Lester, 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 “IMPROVEMENTS
IN PHOTOGRAPHIC APPARATUS," upon the condition (amongst others) that I,
the said Thomas Lester, my executors or administrators, by an instru-
ment 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 Létters
Patent.
.
NOW KNOW YE, that I, the said Thomas Lester, 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, reference being had to the Drawings liereunto
annexed and to the letters and figures marked thereon (that is to
'say) :—
Mix Invention of if Immensaments in Plintaanhio Annoužití

page_text: Hitherto it has been found that when photographs have to be obtained
in open daylight, or far removed from the operating room, this has
involved the necessity of ponderous and expensive apparatus with diffi-
culties and inconveniences in working, and also the liability to frequent
failures in result.
=
5
Now my Invention has for its object the removal of these defects by
the adaptation and application to the camera of a box containing three
parallel baths, into which the collodionized plate may be successively
plunged without exposure to daylight, and from the last of which baths
the plate thus prepared may be transferred to an ordinary plate box in 1
open daylight and finished at leisure. The first of the said three baths
contains the nitrate of silver solution for sensitizing the collodionized
plate; the second contains a solution of protosulphate of iron and acid
for developing the picture; and the third bath contains a mixture of.
honey, iodide of potassium, and water for washing the developed 1
picture.
The baths are made water-tight by means of screws, which pass
through the sliding top of the bath box and press on the bath covers
beneath.
The collodionized plate is plunged into the said baths without coming 2
'into contact with light by means of a dipper, which holds the plate at
one edge, and is passed through a slot formed in the upper part of the
body of the camera, such slot being covered by a slide having in it an
aperture through which the dipper is inserted.
The dipper is so formed that a glass plate can be held firmly by one 2
edge by means of a clamp screw pressing against a stay at the lower
end of the same. There is also a stop on its lower end, which cuts off
any light that may be admitted by the orifice above through which the
dipper is inserted.
The bath box is fitted by means of a slide which is screwed on to the g
lower part of the camera, and which works in a groove in the top of the
bath box.
By means of the apparatus above described a large number of
negatives can be taken in a short time ready to be finished at leisure.
: Having thus stated the nature of the said Invention, I will proceed a
to describe more particularly in what manner the same is to be performed

page_text: parts of the apparatus above referred to.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 represents in perspective the camera with the bath box inserted.
A'is the camera; B, a hinged door or flap opening into the interior of
the camera; C, a slide that is passed over the bath box when the camera
is in use; D, an oval opening for convenience in focussing; E, an opening
for admitting the screws when the bath box is inserted for convenience
in travelling; F, screws as they would appear after the insertion of the
bath box.
Fig. 2 represents the bath box containing three baths, in the first of
which is the nitrate of silver solution for sensitizing the collodionized
plate; in the second a solution of protosulphate of iron acid and sugar
for developing the picture; and in the third a mixture of honey, iodide
of potassium, and water for washing the developed picture. In this
Figure are shown the screws that press on the bath covers to keep the
baths water-tight.
Fig. 3 represents the three parallel baths which are inserted in the
bath box, shewn in Fig. 2, such baths containing respectively silver, iron,
and iodide of potassium, as stated above.
Fig. 4 represents the dipper with a clamp screw at s for holding the
collodionized plate by its edge and immersing it in the baths. There is
also a stop at T for the purpose of cutting off any light that may be
admitted by the orifice through which the dipper is inserted.
Fig. 5 represents the slide on the lower part of the camera for securing
the bath box at the time of operation.
By means of the apparatus above described a large number of
negatives can be taken in a short time ready to be finished at leisure by
the wet process in open daylight without the employment of the ordinary
cumbrous tent, the expensive changing box, the double back, or the
darkened room. The advantages in practice of the wet process over the
dry process are so well known to photographers as not to require any
special reference to them.
Having thus described the nature of the said Invention, and in what
manner the same is to be performed, I hereby-declare-that-what-I claim

page_text: as of my Invention is, the form of photographic camera above described
and the application to the same of a box containing three parallel baths
(with the requisite chemicals therein), into which the collodionized plate
can be successively. plunged by means of the dipper, as described, without
exposure to daylight, and from the last of which baths the plate may be t
transferred to an ordinary plate box in open daylight and the negative
finished at leisure.
In witness whereof, I, the said Thomas Lester, have hereunto set
my hand and seal, the 22nd day of January, in the year of our
Lord One thousand eight hundred and seventy-five.
Witness,
CHARLOTTE VCs. OSSINGTON,
Ossington,
Newark.
THOMAS LESTER. (L.S.)