IMPROVEMENTS IN MINERS' SAFETY LAMPS
Year: 1870

page_text: LETTERS PATENT to Richard Brown, of Glasgow, in the County of
Lanark, North Britain, for the Invention of "IMPROVEMENTS IN
MINERS' SAFETY LAMPS."
Sealed the 23rd May 1871, and dated the 26th November 1870.
PROVISIONAL SPECIFICATION left by the said Richard Brown at tho
Office of the Commissioners of Patents, with his Petition, on the
26th November 1870.
I, RICHARD BROWN, of Glasgow, in the County of Lanark, North
Britain, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MINERS' SAFETY LAMPS," to be as follows, that is
to say :-
This Invention has for its object to render miners' lamps more useful
and safe than as hitherto constructed, and it consists principally in
combining with the ordinary wire gauze shell or casing of such lamps a
suitable lens and reflector.
The lens is secured by means of a groove formed in it round its edge,
and is encircled by a projecting shell of tinned plate or other suitablo
metal of a conical or similar shape. The inner edge of the shell is
fitted into the groove in the edge of the lens, which with the shell is
then inserted within the edge of a short lateral extension of the wire
gauze shell of the lamp, and wire is strongly bound round the whole,

page_text: .
thus firmly securing the parts without solder, without the possibility of
leaving holes larger than the wire gauze meshes, and without obstructing
or contracting the area for the passage of the light through the lens.
The encircling metal shell serves to effectively protect the lens from
breakage, and is polished on its inner side to reflect and disperse the
light, whilst it may be corrugated if desired to increase its reflecting
surface. The extension of the wire gauze shell made for receiving tho
lens is carefully and firmly sewn by wire to the main wire gauze shell,
to avoid soldering and the forming of holes of dangerous size. An
internal reflector is placed on the side of the flame opposite to the lens,
to cause as much light as possible to pass through the lens, and this
reflector is by preference fixed inside of the wire gauze. The bottom of
the lamp is by preference screwed into the upper part, but a mark and
cross catch or screw are provided to lock the sorewed parts together with
the reflector in the proper position. A handle is fixed to the side of the
lamp opposite to the lens to enable the miner to casily hold up the lamp
and direct its light as he may require. The parts of the lamp not herein-
before referred to may be made according to any suitable existing plan.
The improved lamp is very much more useful than the ordinary
miners' safety lamps, on account of its concentrating much more light
on the objects to illuminate which it is directed, whence also arises a
most important clement of safety, as the lamp can in consequence be
placed at a considerable distance from a dangerous point where the
miner may be actually working, and still yield him more light than the
ordinary lamp.
The improved lamp is also much less liable to accident or injury than
some lamps hitherto proposed and consisting partly of glass, as not only.
is the lens of comparatively small sizo, but it is thick in substance, and
not easily broken, whilst it is protected, as already explained, by an
encircling metal shell.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-sixth day of November, in the
year of our Lord One thousand eight hundred and seventy, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Richard Brown, Her special licence that
I, the said Richard Brown, my executors, administrators, and assigns,
or such others as I, the said Richard Brown, my executors, adminis-
trators, 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 MINERS'
SAFETY LAMPS," upon the condition (amongst others) that I, the said
Richard Brown, 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
bo 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 Richard Brown, 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 in writing, reference being had to the accompanying
Drawings, that is to say :—
My said Invention has for its object to render miners' safety lamps
more useful and safe than as hitherto constructed, and it consists
principally in a mode of combining with the ordinary wire gauze shell
or casing of such lamps a suitable lens and reflector.
And in order that my said Invention and the manner of performing
the same may be properly understood, I hereunto append a Sheet of
explanatory Drawings, to be herein-after referred to, and representing
a miners' safety lamp as made with my improvements.
Figure 1 is a front elevation, and Figures 2 and 3 are horizontal and
vertical sections, the last being as at right angles to Figure 1.
The lamp is shown as provided with a simple plano-convex lens, but
it will be obvious that my improved mode of fitting the lens and other
parts is equally applicable to lenses of various sections.

page_text: The lens 1 is secured by means of a groove 2 formed in it round its
edge, and lenses that will answer the purpose very well may be made by
simply moulding the glass with the groove 2 in it. The lens is encircled
by a projecting shell 3 of tinned plate or other suitable metal of a conical
or other similar shape, and the inner edge of this shell 3 is fitted into
the groove 2, in the edge of the lens 1, a strip of thin rubber, shown
by a thick black line in the Drawing, being by preference interposed
between the glass and the shell 3. The shell 3 with the lens in it is
then inserted within the edge of a short lateral cylindrical extension 4
of the wire gauze shell of the lamp, and the whole is strongly bound
together by one or more wires 5, applied so as to hold the parts in the
groove 2, thus firmly securing them without solder, without the pos-
sibility of leaving holes larger than the wire gauze meshes, and without
obstructing or contracting the area for the passage of the light through
the lens. The encircling conical metal shell 3 serves to effectively
protect the lens 1 from breakage, and is polished on its inner side to
reflect and disperse the light, whilst it may be corrugated if desired to
increase its reflecting surface. The extension 4 of the wire gauze shell
made for receiving the lens 1 is carefully and firmly sewn with wire to
the main wire gauze shell 6, to avoid soldering and the forming of holes
of dangerous size. As a precaution and for strength I prefer the sewing
to be done with two distinct lines of wire, as indicated by the two
strongly drawn circular arcs 7 in Figure 3. An internal reflector 8 is
placed on the side of the flame opposite to the lens 1, to cause as much
light as possible to pass through the lens, and this reflector 8 is by
preference fixed inside of the wire gauze shell 6. The bottom 9 of the
lamp is by preference screwed into the upper part, but a mark and cross
catch or screw 10 are provided to lock the screwed parts together with
the reflector in the proper position. A handle 11 is fixed to the outside
of the lamp opposite to the lens 1, to enable the miner to easily hold up
the lamp and direct its light as he may require, and this handle is
sharpened at its bottom end, so that the miner can fix it in the side of a
"tree." The parts of the lamp not herein-before referred to may be
made according to any suitable existing plan. When the lamp is likely
to be used in localities which are not only dangerous, but also traversed
by strong and sudden currents, I apply segmental shields 12, indicated
by red lines in Figure 2. The middle one of these shields is a fixture
behind the reflector, whilst the other two are capable of sliding round,.

page_text: one each side from behind the middle one to a greater or less extent,
as may be required.
My improved lamp is very much, more useful than the ordinary
miners' safety lamp, on account of its concentrating much more light
on the objects to illuminate which it is directed, whence also arises a
most important element of safety, as the lamp can in consequence be
placed at a considerable distance from a dangerous point where the
miner may be actually working, and still yield him more light than the
ordinary lamp.
. My improved lamp is also much less liable to accident or injury than
some lamps hitherto proposed and consisting partly of glass, as not only
is the lens of comparatively small size, but it is thick in substance,
simple in form, and not easily broken, whilst it is protected, as already
explained, by the encircling metal shell 8.
Having thus particularly described my said Invention and the manner
in which the same is to be performed, I have to state that what I believe
to be novel and original, and claim as secured to me by the herein-before
in part recited Letters Patent is,-
1. The constructing of miners' safety lamps with lenses fitted and
applied as herein described and delineated.
2. The applying of the encircling protective shell (3).
3. The applying of the handle 11.
In witness whereof, I, the said Richard Brown, have hereunto set
my hand and seal, this Twenty-fourth day of May, in the year of
our Lord One thousand eight hundred and seventy-one.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
RICHARD BROWN. (L.S.)