AN IMPROVED LIGHT, APPLICABLE FOR MAGIC LANTERNS, THEATRES, AND OTHER PURPOSES, AND APPARATUS CONNECTED THERE WITH
Year: 1877

page_text: LETTERS PATENT to Walter Bentley Woodbury, of Manor House, South
Norwood, in the County of Surrey, for the Invention of "AN IMPROVED LIGHT,
APPLICABLE FOR MAGIC LANTERNS, THEATRES, AND OTHER PURPOSES, AND
APPARATUS CONNECTED THERE WITH." A communication from abroad by
Romain Talbot, of Berlin.
Sealed the 15th September 1877, and dated the 19th March 1877.
PROVISIONAL SPECIFICATION left by the said Walter Bentley Woodbury
at the Office of the Commissioners of Patents on the 19th March 1877.
WALTER BENTLEY WOODBURY, of Manor House, South Norwood, in the County
of Surrey.
"AN IMPROVED LIGHT, APPLICABLE FOR MAGIC LANTERNS, THEATRES,
AND OTHER PURPOSES, AND APPARATUS CONNECTED THEREWITH." A communication
from abroad by Romain Talbot, of Berlin.
These improvements consist in replacing the ordinary mixed gases, oxygen and
hydrogen, or oxygen and spirit, which are now used to produce the light commonly
known as lime light, by a mixture of hydrogen and heated air or of heated
hydrogen and air in combination, these being caused to be impinged on to lime,
platina, or other substance which becomes incandescent when subjected to an
intense heat.
The apparatus consists of a modification of what is generally known as the
Fletcher blow pipe, in which a mixture of hydrogen and hot air are used for fusing
metals. On a suitable stand is attached a pipe, having two branches, into either
or both parts of which by means of a single tap a stream of gas may be made to
flow; into the upper pipe is inserted a smaller one which is brought out and twisted
round the other pipe near its mouth, and through which compressed air is forced,
the air and the gas mingling at the mouth of the larger pipe. The end of this
double pipe is bent back in the direction of the stand, so as to impinge on to the
disc of lime, leaving a clear space in front of the light; the second pipe conveys gas
to a Bunsen burner placed under the double pipe so as to heat the air and gas as
they leave the nozzle.
The construction of the disc where lime is used is as follows:-A stout ring of

page_text: metal bevelled inside, and with a rack below the surface of its circumference, is
made to lie loosely in a cradle on two small movable wheels, and is turned round
as required from the back by a small pinion. The whole disc and frame can be
raised or lowered by a screw clipping it on to the pipe carrying the Bunsen
burner.
The hydrogen used may be either made from iron or zinc and acid, ordinary coal
gas, or that obtained from spirit, petroleum, or like materials.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Walter Bentley Woodbury in the Great Seal Patent Office on the
19th September 1877.
WALTER BENTLEY WOODBURY, of Manor House, South Norwood, in the County
of Surrey.
"AN IMPROVED LIGHT, APPLICABLE FOR MAGIC LANTERNS, THEATRES,
AND OTHER PURPOSES, AND APPARATUS CONNECTED THEREWITH." A communication
from abroad by Romain Talbot, of Berlin.
This Invention relates to improvements in that form of light (well known as
the "lime" light), in which a jet of mixed oxygen and hydrogen gases, or oxygen
gas and the vapour of spirit, is directed when ignited upon lime or other substance
capable of sufficient incandescence when subjected to intense heat. It has for its
object novel methods of construction and arrangement of the apparatus to produce
light of such kind, in which a mixture of hydrogen gas and heated atmospheric
air, or of atmospheric air and heated hydrogen gas, or both air and gas heated is
used instead of the compounds above described, and is caused to impinge when
ignited, upon lime, platina, or other substance capable of becoming sufficiently
incandescent under the intense heat thus produced and of sufficiently resisting such
heat. By these improvements the apparatus in rendered simpler, cheaper, and more
effective, and its several parts are more readily accessible for adjustment than in
such apparatus as heretofore constructed and used.
In order to put this Invention in operation I take a suitable stand, to which is
nttached or connected a pipe, having two branches, into either or both of which
a stream of gas may be admitted and regulated, as desired, by means of one or more
stop-cocks. Through the side and near the outer end of one of the branches thus
arranged, which is placed above the other, a pipe of smaller diameter is inserted, its
end being concentric or nearly so with that of the surrounding one, and being
formed into a jet, and this smaller pipe after passing out of the larger pipe is wound
helically round the latter, and its end is then re-inserted through the side of the
pipe, and having been carried inside the latter to any desired point is again brought
out through its side. To the outer end of the small pipe thus brought to a con-
venient position is connected a pipe through which compressed air can be forced
into it, and after passing through the helical coils is discharged through the jet at
its extremity, concentric with the mouth of the outer pipe, as already described.
.When gas is at the same time admitted through the outer pipe it mixes at the
mouth of the latter with the compressed air discharged through the jet, and the
double or compound pipe thus constructed is bent back so that the mixed jet of
gas and air is directed upon a disc of lime or other suitable material, arranged as
herein-after described. The second of the branches into which the gas pipe is
divided, as already explained, has a jet inside a pipe to which air is admitted, and
the end of this pipe is carried up and ends in a jet of suitable shape and size under
the helically coiled air pipe so as to form what is well known as a "Bunsen "
burner, by which the air in the coils and the gas in the inner pipe are heated to a
high temperature before they reach the compound jet.
By the method of construction described the apparatus is made very compact,
portable, and easy to regulate. The ignited jet, formed as above described, is

page_text: directed upon a disc of lime, platina, or other substance capable of sufficient incan-
descence, constructed and arranged in the following way-A sufficiently strong
ring of metal, having a slightly conical aperture through it, is arranged vertically
upon its edge and is supported upon horizontal friction- rollers so that it can be
made to revolve freely. In its edge is formed a circular toothed rack which engages
into a toothed pinion upon an axis, at the other end of which is a thumbscrew or
handle, by turning which the ring can be made slowly to revolve. The friction
rollers and pinion axis are carried in a frame which slides upon the upright part of
the pipe which forms the "Bunsen" burner already described (or to other convenient
part of the apparatus), and can be adjusted to any desired position, and it is so
arranged that the ignited compound jet already described is directed downward
and backward so as to impinge upon the front of. the disc at a point between the
centre and edge of the latter, which point becomes incandescent and the source of
intense light.
In the accompanying Drawing Figure 1 is an illustration of my Invention, and
is a side view partly in section of the apparatus.
a is the stand, provided with a pipe b, into which gas is admitted from any con-
venient source of supply through the junction c. The pipe b is divided into two
branches d and e, the supply of gas to either which can be regulated by the stop-
cocks g; the branch & has the smaller pipe h inserted into it at i, which pipe is
brought out again at h, and is then coiled round the pipe d, after which, it is re-
inserted into the latter and ends in a jet concentric with the latter, as shewn in
dotted lines. The branch e has a "Bunsen" burner formed at its upper end at m
under the small coiled pipe, an opening being formed in it at n through which air
is admitted to mix with the gas which passes through a jet regulated by the stop-
cock g. The disc of lime or other material o is fitted into a conical opening in the
ring p, which is carried upon friction rollers in the frame ?, which is adjusted upon
the branch pipe e. The ring p has a toothed rack round its circumference, so that
it can be made to revolve by the pinion and spindle 8.
The action of the apparatus is as follows:-Gas being admitted at c is allowed
to pass into the branch pipes d and e; compressed air is admitted into the smaller
pipe at i, and after passing through the coils in the latter is discharged, mixed with
gas from the pipe à in a jet upon the disc o. The mixed gas and air passing
through the pipe e are burned at l, and sufficiently heat the air in the small pipe
and the gas in the pipe d before they are discharged upon the disc o. The conical
form of the ring p allows the disc o to be readily replaced, and it can be turned
round by the pinion s so as to present a fresh part of its surface to the jet when
necessary, or the ring may be reversed so that the back of the block can be used.
Instead of the method of operation described, gas may be forced into the small
coiled pipe, and air may be admitted through the pipe d.
Another novel form of arrangement, which I sometimes use when the light is
required in more than one direction, is shewn in Figures 2, 3, and 4, Figure 2
being a side view; Figure 3, a plan; and Figure 4, a vertical section of part of the
apparatus where four burners are to be used. a is an outer pipe through which gas
is admitted, and b is an inner pipe through which compressed air is forced, as in the
arrangement first described; c is a tubular ring into which the gas is admitted from
the pipe a through the radial pipes d, d, d, d. Four small pipes e (only one being
shewn in the Drawing) cominunicate with the upper end of the compressed air
pipe b', and each after being coiled round a part of the ring centers one of the four
branch pipes f (of which one only is shewn), upon the latter the ends of which are
directed upward and inward upon a conical disc or block g, of lime, sheet platina,
or other suitable material, which is carried by the central vertical spindle h, upon
which it can be turned round when desired. From this gas pipe a, four jets issue,
regulated by the stop-cocks i and entering the air tubes k, having openings at l, so
that their upper ends form "Bunsen" burners m under the coiled pipes.
The action of the apparatus is similar to that first described, but four incandescent

page_text: spots instead of one only are formed upon the disc of lime or other material. The
apparatus may be arranged in any convenient position.
The gas used may be either ordinary coal gas, or the vapour of spirit, petroleum,
or other suitable vaporizable hydrocarbon; or it may be produced by the action of
diluted acid upon iron or zinc in the way well understood and practised.
Instead of using lime or platina to receive the jet or jets of ignited gas in the
different forms of apparatus described, I sometimes use compressed carbonate of
lime or compressed carbonate of lime and asbestos combined.
Having now described the Invention and the manner in which it is to be per-
formed, I claim,—
The combination of a compound jet conveying gas and air, heated by one or more
"Bunsen" burners, such compound jet being directed downward and backward
against a vertical disc of incandescent material so as to produce an intense light
without interfering with the effective use for magic lanterns, theatres, or other
purposes, of the light so produced, substantially as described and shewn in the
Drawing.
Also, the conical ring carrying a block of lime or other incandescent material
and resting freely upon rollers in an adjustable frame attached to the apparatus,
the ring being turned round as desired by a pinion acting upon a rack on its
circumference, substantially as and for the purpose described and shewn in the
Drawing.
Also, the arrangement of a central conical block of lime or other incandescent
material turning freely upon a vertical support, in combination with two or more
compound jets of gas and compressed air directed upon the conical block from a
tubular ring and heated by "Bunsen" burners so as to produce intense light in
several directions, substantially as described and shewn in the Drawing.
In witness whereof, I, the said Walter Bentley Woodbury, have hereunto set
my hand and seal, this Nineteenth day of September, in the year of our
Lord One thousand eight hundred and seventy-seven.
TT MAD
DAVALRY
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