IMPROVEMENTS IN GOVERNING OR REGULATING LIGHT USED FOR TAKING PHOTOGRAPHIC PORTRAITS AND OTHER PHOTOGRAPHIC PICTURES, PART OF WHICH IMPROVEMENTS IS ALSO APPLICABLE TO LIGHTING PICTURE GALLERIES
Year: 1862

page_text: LETTERS PATENT to Lachlan M°Lachlan, of Manchester, in the County
of Lancaster, Photographic Artist, for the Invention of "IMPROVEMENTS IN
GOVERNING OR REGULATING LIGHT USED FOR TAKING PHOTOGRAPHIC PORTRAITS
AND OTHER PHOTOGRAPHIC PICTURES, PART OF WHICH IMPROVEMENTS IS ALSO
APPLICABLE TO LIGHTING PICTURE GALLERIES."
Sealed the 24th October 1862, and dated the 25th April 1862.
PROVISIONAL SPECIFICATION left by the said Lachlan M°Lachlan at
the Office of the Commissioners of Patents, with his Petition, on the
25th April 1862.
I, LACHLAN MCLACHLAN, of Manchester, in the County of Lancaster,
Photographic Artist, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN GOVERNING OR REGULATING LIGHT USED FOR TAKING PHOTO-
GRAPHIC PORTRAITS AND OTHER PHOTOGRAPHIC PICTURES, PART OF WHICH IMPROVE-
MENTS IS ALSO APPLICABLE TO LIGHTING PICTURE GALLERIES," to be as follows:-
My Invention consists, firstly, in a method of preventing the direct rays of
the sun from falling upon the sitter or other object to be copied, and of modi-
fying or directing the light as occasion may require. To these ends I employ
a series of strips of wood or other material hanging downwards or projecting
sideways, between which the light enters, and which may be inclined to any
desired angle. Also, I place within the spaces formed by these strips series
of partitions which may also be moved to any angle so as to govern the light

page_text: in the other direction. As this part of my Invention affords means for throwing
the light in any direction it is applicable to picture galleries.
Another part of my Invention relates to a method of preventing the light
from being reflected from the surface used as a background in taking photo-
graphic portraits. For this purpose I employ a background of gauze or
other partially transparent substance, so that the light may pass through it
and become absorbed. To assist which I place behind the gauze a surface of
black velvet or other such material. Or I propose employing two or more
screens of gauze or other such material, and adapting one or more of them so
that it or they may be brought nearer to or farther from the front one, and I
also propose so to arrange them that one or more may be placed at an angle
to the front one.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Lachlan McLachlan in the Great Seal Patent Office on the
25th October 1862.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LACHLAN
MCLACHLAN, of Manchester, in the County of Lancaster, Photographic Artist,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of April, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Lachlan McLachlan, Her special license that I, the said Lachlan.
McLachlan, my executors, administrators, and assigns, or such others as I
the said Lachlan M Lachlan, 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 GOVERNING OR REGULATING LIGHT USED FOR
TAKING PHOTOGRAPHIC PORTRAITS AND OTHER PHOTOGRAPHIC PICTURES, PART OF
WHICH IMPROVEMENTS IS ALSO APPLICABLE TO LIGHTING PICTURE GALLERIES," upon
the condition, amongst others, that I, the said Lachlan McLachlan, 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

page_text: 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 Lachlan M Lachlan, do hereby declare
the nature of my said Invention, and in what manner. the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement and accompanying Drawings, that is to say:—
My Invention consists, firstly, in a method of preventing the direct rays of
the sun from falling upon the sitter or other object to be copied, and of
modifying or directing the light as occasion may require. This part of my
Invention I divide into two portions, in the first instance I cause strips of
wood or other suitable material to hang downwards from the roof at such a
distance apart, and of such a depth as to shut out the direct rays of the sun.
These strips, if desired, I hang upon centres, so that they may be inclined
to any angle. Or in addition to the strips above mentioned I place cross
pieces within the spaces formed by such strips, which cross pieces may also be
moved to any angle, so as to govern the light in the other direction.
The second division of this part of my Invention refers to the side light, in
order to govern which I use projecting slips extending sideways, but in this
instance I do not use these by themselves but in combination with partitions
situated within the spaces between them.
M
Another part of my Invention relates to a method of preventing light from
being reflected from the surface used as a background in taking photographic
portraits..
:
And, lastly, my Invention consists in the application of the above-mentioned
method of regulating light to the lighting of picture galleries.
In order that these improvements may be clearly understood, I will now
refer to the Drawings accompanying this my Complete Specification.
Fig. 1 is a Diagram representing a photographic, gallery in section, and
shewing the most simple method I adopt for regulating the top light. The
sun's path, being substantially in the direction of the arrow, the roof is at 1, 2,
hanging down from which are strips of wood or other material 3. These
strips are placed at such a distance apart in relation to their depth that at the
greatest altitude of the sun the direct rays thereof will not pass through the
spaces between them. In the Fig. they are represented as running parallel
with the sides of the gallery, but they may be placed at any angle thereto,.
and this will, of course, be determined by the aspect of the gallery, and con-
sequently the sun's path in relation thereto. The above arrangement may,
according to my Invention, be used by itself, but I will now describe how, by
another part thereof, an additional power over the light may be obtained.

page_text: Fig. 2 represents upon a larger scale a portion of the roof in cross section,
that is a part of Fig 1; and Fig. 3 is a view of a portion of the under side of
the roof, that is as it would appear. when looking upward from the floor.
The strips above mentioned, in reference to Fig. 1, are at 3, between which
are placed partitions 4. These partitions are carried by cross bars 5 capable
of turning in bearings at each end, but one bearing 6 only is shewn, that on
the other side of the gallery being represented as broken off. To the cross
bars 5 are attached cranks 7 connected together by a rod 8; if therefore this
rod 8 be moved to or fro the cross bars 5 will be caused to turn upon their
centres, and thus the partitions 4 may be caused to direct the light vertically
or to either end of the gallery, and if these partitions be connected to the cross
-bars 5 by centre pins, so as to be capable of turning thereon, the strips 3
may also be angled, so as at the same time to throw the light across the
gallery in the one direction or the other.
I now proceed to illustrate the second division of this part of my Invention,
namely, the regulation of the side light. Fig. 4 represents a portion of a
photographic gallery in cross section, and Fig. 5, a face view of the same, the
side light is at 9, 10, projecting side ways from which are strips 3 mounted at
the top and bottom of the gallery, so as to be capable of turning upon centres,
and therefore of being moved to any angle; between the strips are placed
partitions 4 mounted upon cross bars 5, which are provided with cranks after
the manner described in reference to Figs. 2 and 3, and they may therefore
in like manner be turned upward or downward so as to direct the light in
either direction or to modify its intensity. The strips 3 may be stationary,
but if it be desired to provide for their turning upon centres at top and bottom,
then the partitions 4 are mounted upon centre pins carried by the cross bars
5, so as to allow the said partitions to accommodate themselves to the angles
assumed by the strips 3. In concluding the description of this part of my
Invention, I would observe that although I have spoken of the roof and
side lights as being constructed as above, a portion only thereof may be so
arranged, if desired, and that series of strips, or strips and partitions, may be
mounted in separate frames so as to expose portions of bare glass when
desired. I have also alluded particularly to glass rooms, but my Invention is
also applicable to out-door photography, in which case the only difference will
be that the strips, or strips and partitions, will form a roof or side without
glass over them, and for this purpose, namely, out-door photography, the
whole may be made of a portable character, strips of calico or other such
material being used. I have also in the above description alluded to this part
of my Invention as applied to photographic purposes, but the same arrange-

page_text: ments are also applicable to picture galleries, the direction of the light being
under perfect control. The next part of my Invention is illustrated at Figs. 6
and 7, in which the framework of the background is shewn at 12; over this
is stretched a surface 18 of gauze or other material, which is partially trans-
parent. Behind this is placed black velvet 14, or other material which will
absorb light, the effect of which is, that instead of the light being reflected
from the surface 12 it passes through it and becomes absorbed by the back
screen 14; or, I use a second transparent surface drawn in red at 15, and by
placing this at an angle as shewn, or at any other angle, and confining it
thereto by bolts passing through rails at each side as at 16, or by other con-
venient means, one part of the background may be obtained of a darker
shade than the other.
Having thus described and ascertained the nature of my said Invention, and
the manner of carrying the same into effect, I desire it to be understood that
I claim as secured to me under the above in part recited Letters Patent,―
Firstly, as applied to top lights; the use of the strips as illustrated at Fig. 1,
and also of the strips and partitions as illustrated at Figs 2 and 3.
Secondly, as applied to side lights, the use of the strips and partitions as
illustrated at Figs. 4 and 5.
Thirdly, the employment of a transparent or semi-transparent background.
Fourthly, the application of the arrangements above described in references
to Figs. 1, 2, 3, 4, 5, to the purpose of regulating the light in picture galleries.
In witness whereof, I, the said Lachlan McLachlan, have hereunto set
my hand and seal, this Twenty-fourth day of October, in the year of
our Lord One thousand eight hundred and sixty-two.
L. M'LACHLAN.
(L.S.)