IMPROVEMENTS IN APPARATUS AND APPLIANCES FOR PRODUCING INTENSE WHITE LIGHT
Year: 1882

page_text: LETTERS PATENT to John Imray of No. 28 Southampton Buildings in the
County of Middlesex for an Invention of IMPROVEMENTS IN APPARATUS
AND APPLIANCES FOR PRODUCING INTENSE WHITE LIGHT A communication
from abroad by Charles Clamond of Paris France Engineer
COMPLETE SPECIFICATION filed by the said John Imray at the Office of
the Commissioners of Patents on the 29th April 1882.
JOHN IMRAY of No. 28 Southampton Buildings in the County of Middlesex
"IMPROVEMENTS IN APPARATUS AND APPLIANCES FOR PRODUCING INTENSE
WHITE LIGHT," A communication from abroad by Charles Clamond of Paris,
France, Engineer.
The
In the Specification to Letters Patent granted to me on the 24th May 1880
No. 2110 for an Invention communicated to me from abroad by Charles Clamond
were described arrangements for heating to a very high degree the air supplying an
illuminating jet by means of a second heater placed above the true illuminating flame,
and methods of preparing and arranging the magnesia so that when highly heated by
the jet it radiates a white light. The present Invention relates to improvements in
the apparatus and appliances employed for this purpose, as I will explain referring
to the accompanying Drawings. Figs. 1 and 2 represent respectively a vertical
section and a sectional plan of apparatus by which the heat of the products of
combustion is partially recovered and thus considerable economy is secured.
air current arriving by the pipe D descends the tube C as previously described and
becomes heated before reaching the jet S. A portion of the air regulated by the
screw branches off by the pipe T and descends by N into the annular space B.
The gas supplied by the pipe F enters the space E in quantity regulated by the
adjusting screw g. From E four tubes L conduct the gas to the ring R which
distributes it to the jet as previously described. A portion of the gas regulated by
the screw fpasses by N into B, which thus becomes charged with a mixture of gas
and air in proportions regulated by the screws f and n. This mixture descends
the four tubes K and issues from them by the orifices o in jets m which are ignited

page_text: and heat the tube C. The whole is enclosed in a casing M, which operates as a
chimney, having at the top lateral apertures Z by which the products of com-
bustion issue. At the bottom the casing terminates in two concentric cores
connected by cross tubes J and supports a basket of woven magnesia shewn
separately by Fig. 4 and made as will hereafter be described. Through this basket
the jet flame passes producing the light, and by the draught caused by the casing M
the products of combustion ascend by the annular passage p whilst air entering by
the cross tubes J becomes heated and aids in supporting the combustion of the
small flames m. It is obvious that the tubes K and L as well as the spaces B
and E are heated by the products of combustion as they ascend within the casing M,
a considerable portion of their heat being thus recovered.
For producing the magnesian threads or baskets the process is as follows: —
Magnesia calcined and pulverised is rendered highly plastic by thoroughly mixing
it with a solution of a salt of magnesia that is readily decomposed by heat,
particularly the acetate of magnesia. The plastic paste being put into a cylinder
and subjected to moderate pressure by a piston, is caused to issue in continuous
threads or tubes through a suitable die. These are then dried and thoroughly
baked; during which operation the acetate becomes decomposed and, the acetic acid
being driven off, there remains only compact and solid magenesia in the original form.
In this manner are prepared the magnesian threads or needles required, which
are employed in forming the basket shewn by Fig. 4. Thus the magnesian threads
as they issue from the die are wound on a bobbin or mandril which turns first on
an oblique axis and then on an axis at right angles to the former so that the
threads cross each other and adhere at their crossings, thus forming a net work
which being dried and baked constitutes the basket of magnesia thread. The
basket may be cased over with paper or other combustible material so as to
strengthen it for transport and handling, this casing being burnt away when the
jet is ignited. The magnesian basket is supported in a basket T Fig 3 made of
platinum wire or other refractory metal, with large meshes attached to a ring N
provided with a bayonet catch or its equivalent, so that it can readily be removed
to replace in it the magnesia basket. A modified construction of the apparatus is
shewn by the vertical section Fig. 5, and the other Figures 6, 7 and 8 which will
be hereafter referred to, the parts corresponding with those shewn in Figs. 1 and 2
being marked by similar letters. The space E is in this case placed above B so
that the diameter of the apparatus can be reduced, and these spaces are supplied
respectively with gas and with the mixture of air and gas regulated as described
with reference to Fig. 1, the passages and adjusting screws being arranged in the
body of the casting. Instead of employing a basket such as is shewn by Fig. 3
for supporting the magnesia, an open frame of wire is used, which gives freedom
for the magnesian basket to slide when it becomes highly heated. The upper part
of the apparatus consists of four discs V U Q and Y bolted on one another. In Q
and Y are the cavities forming the chambers E and B. The chamber B supplies
the gaseous mixture by the four tubes K for the jets m, and the chamber E supplies
gaseous mixture to the four tubes L which pass through B and conduct the mixture
to the refractory ring R whence it issues to join the air which heated by descending
the tube C issues by numerous small orifices 8. The two discs V and U contain the
arrangements for the distribution of the gas and air as shewn by the plans Figs. 6
and 7 and the section Fig. 8 taken at right angles to that shewn by Fig. 5. In
each of the discs V and U are formed two circular chambers A and A¹ which
correspond exactly when the discs are superposed. In U these chambers are
connected by a passage from the gas supply F consisting of a circular groove
provided with adjusting screws b and g to operate as stop-cocks. In like manner
in V, the chambers A and A¹ are connected to the air supply D by a passage having
adjusting screws n n³, there is also a passage D₁ governed by a screw d to the
central hole D¹. The two discs are separated by a partition v¹, as shewn in Fig. 8.
The air from the upper chambers A A' passes through small holes y in the
partition v' and mixes with gas entering by the passage Z' and the mixture passes

page_text: through larger holes y¹ exactly opposite the holes y in a second partition n¹. A
portion of the mixture passes by a hole in the bottom of A direct into the space E,
and another portion passes from A' by a lateral passage N into the space B. It
will be readily seen that though this apparatus differs somewhat in construction
from that shewn by Figs. 1 and 2, its operation is substantially the same.
Having thus described the nature of this Invention and in what manner the
same is to be performed as communicated to me by my foreign correspondent, I
claim in respect of apparatus for producing intense white light.-
First. The construction substantially as described with reference to Figs. 1
and 2.
Second. The modified construction substantially as described with reference to
Figs. 5, 6, 7 and 8.
Third. The process for preparing magnesian network, substantially as herein
described.
In witness whereof I the said John Imray have hereunto set my hand and
seal this Twenty-ninth day of April in the year of our Lord One thousand
eight hundred and eighty-two.
JOHN IMKAY. (L.S.)