AN IMPROVED AIR-RAREFYING LAMP BURNER
Year: 1872

page_text: LETTERS PATENT to Thomas Silver, of the City and State of New
York, United States of America, now of Moorgate Street, in the
City of London, Gentleman, for the Invention of "AN IMPROVED
AIR-RAREFYING LAMP BURNER."
caled the 4th February 1878, and dated the 7th August 1872.
PROVISIONAL SPECIFICATION left by the said Thomas Silver at the
Office of the Commissioners of Patents, witli his Petition, on the
7th August 1872.
-
I, THOMAS SILVER, of the City and State of New York, United States
of America, now of Moorgate Street, in the City of London; Gentleman,
do hereby declare the nature of the said Invention for "AN IMPROVED
AIR-BAREFYING LAMP BURNER," to be as follows:-
My said Invention relates to a 'peculiar contrivance which fully
obviates the necessity for the glass chimneys heretofore used upon lanips
for preventing the production of smoke and unpleasant odours therefrom.
Morcover the said apparatus permits the wick to be regulated to givê
as much or as little light as may be désirable at any timo, so-that the
lamp may be used with equal advantage in reading or other occupations
requiring a strong light or as a night light, and in other cases where a
dim light is desirable.or sufficient.

page_text: My improved burner is constructed as follows:-The wick tube is
attached to a cylindrical piece which is formed with the ordinary screw
to connect it with the lamp, and is provided with the usual appliance
for adjusting the wick. At the side of the said wick tube I place a small
flat tube which extends through the cylindrical part of the burner and
serves to conduct any gas that may be generated within the lamp up to
the point of ignition where it will be consumed. Over the wick tube
I place a conical or bell-shaped metal cover which is attached by cross
bars or arms to a central socket; the latter has an opening for the
passage of the wick tube and is made to rest upon the cylindrical part
of the same. This cover encloses a peculiar contrivance for heating and
rarefying the air within the said cover, and producing a rapid current or
draught of the same through the cover to the flame of the burner. This
contrivance consists of an inner cone of thin metal either in the form
of a continuous plate. or a series of strips, the same being arranged to
surround the wick tube and extending from the top to the bottom of
the aforesaid conical or bell-shaped cover. The said strips are formed
by cutting a thin circular metal plate in such a manner that the strips
are separated from each other except at the top, the latter forming a
ring from which the said strips hang around the wick tube. The said
strips may be flat or curved or V shaped in transverse section, and they
may be set transversely to radial lines drawn through them to the centre
of the burner or may be twisted to stand parallel or nearly so with such
radial lines; or the said strips may be crimped or corrugated transversely
from their upper to their lower ends.
When the rarefier or heater is made in the form of a continuous or
undivided conical plate, the same should be corrugated cither vertically
or circularly.
I sometimes have the said rarefier or heater secured rigidly to tho
outer cover. In this case I prefer to attach the said rarefier to the cover
by fitting portions of it between the aforesaid cross bars and the cover,
and securing these parts by small rivets; but if it is desired to have the
outer cover adjustable vertically in relation to the rarefier I fit the same
to slide upon the central socket or other part of the burner, and provide
it with an adjusting roller and button or other suitable contrivance for
the purpose.
The top of the rarefier or heater has an aperture for the passage of the
flame, and the outer cover also has an aperture of corresponding shape

page_text: but somewhat larger. Any ordinary or suitable wick may be used and
the aforesaid burner may be applied to lamps of any shape or con-
struction; and although the object of my said Invention is the provision
of an apparatus which obviates the necessity for a glass chimney to
5 prevent the smoking of the lamp, yet I may construct the cover with a
rim or gallery upon which a chimney may be placed to prevent the
extinction of the flame by a draught or current of air when the lamp is
carried or placed in exposed situations.
SPECIFICATION in pursuance of the conditions of the Letters l'atent,
filed by the said Thomas Silver in the Great Seal Patent Office on
the 7th February 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
SILVER, of the City and State of New York, United States of America,
now of Moorgate Strect, in the City of London, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of August, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Thomas Silver, Her special licence
that I, the said Thomas Silver, my executors, administrators, and
assigns, or such others as I, the said Thomas Silver, 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 terin
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 "AN IMPROVED AIR-
BAREFYING LAMP Burner,” upon the condition (amongst others) that I, the,
said Thomas Silver, 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
be filed in the Great Seal Patent Office within six calendar months
next and immediately after the date of the said Letters Patent.

page_text: capability of removing the cover from the wick tube is an important feature
of my Invention, and will be found very advantageous. The outer bell-
shaped piece c' encloses the cone c, the latter being arranged to surround
the wick tube b. These two cones or bell-shaped pieces form a peculiar
contrivance for heating and rarefying the air and producing a rapid
current or draught of the same through the cover to the frame of the
burner, and although the shape of the said inner cone may be varied or
modified as shewn in the Drawing, the two cones must in all cases be
so formed and fitted together that there will be an unobstructed passage
to the flame, not only inside the inner cone but also between the two
cones as indicated by the arrows in Figures 2, 4, 5, and 6. This arrange-
ment of the two cones distinguishes my Invention from other contrivances
of a like character. I am aware that argand burners have been already
constructed with a cover consisting of two domes placed over the burner,
but in these contrivances there is no provision for the free passage of the
air between the domes, and therefore they do not accomplish the object
attained by my Invention.
In Figure 2 this inner piece c, is a bell-shaped piece having the
same form or configuration as the outer picce c', and is perfectly plain
and smooth on its periphery, that is to say, if detached from the other
parts of the cover it would with the exception of the opening in the top
resemble an ordinary hand bell. In Figures 5 and 6 it has the same
sectional form or outline, but in Figure 5 it is formed with corrugations
extending from the bottom nearly to the top, and in Figure 6 it has
circular corrugations. In Figure 4 the said inner piece is a metallic
fringe made by cutting a circular metal plate into strips in such a manner
that the strips are separated from each other except at the top; the
latter forming a ring from which the said strips hang around the
wick tube b. These strips may be flat, curved, or V shaped in transverse
section, and they may be set transversely to radial lines drawn through
them to the centre of the burner, or may be twisted to stand parallel or
nearly so with such radial lines. Or the said strips may be crimped or
corrugated transversely from their upper to their lower ends. But in
all these varied forms of the inner piece c² there must be a clear space
between the same and the outer piece c¹ for the free passage of the air,
as above specified.
I prefer to have the said inner piece or rarefyer or heater & secured
moilly to the outan moniaal views 1 T. TTL
1

page_text: inner piece attached to the outer piece of the cover by fitting strips of the
fringe between the aforesaid cross bars c³ and the piece c³, and securing
theso parts by small rivets. In Figures 2, 5, and 6, I have shewn the
two pieces c¹, c³, attached to each other by the cross bars, but if it is
desired to have the outer piece adjustable vertically in relation to the
inner piece of the cover, I fit the said outer picce to slide upon the
central socket or other part of the burner and provide an adjusting roller
and button or other suitable contrivance for the purpose.
The top of the rarefyer or heater c² has an aperturef for the passage
of the flame, and the outer piece c¹ also has an aperture g of corre-
sponding shape but somewhat larger. Any ordinary or suitable wick
may be used, and the aforesaid burner may be applied to lamps of any
shape or construction; and although one object of my said Invention is
the provision of an apparatus which obviates the necessity for a glass
chimney to prevent the smoking of the lamp, yet I may construct the
cover c with a rim or gallery upon which a chimney or globe may be
placed to prevent the extinction of the flame by a draught or current of
air when the lamp is carried or placed in exposed situations. But it
must be distinctly understood that a lamp provided with my Invention
will not in any case require a chimney for the same reason that other
lamps require chimneys or equivalent contrivances, and that in this
respect, viz., in the capability of producing a pure and brilliant light
without a chimney or analagous contrivance, my said Invention is distinct
from all other known contrivances for similar purposos.
In witness whereof, I, the said Thomas Silver, have hereunto set
my hand and seal, this Sixth day of February, in the year of our
Lord One thousand eight hundred and seventy-three.
Witness,
W. ROBT. LAKE,
8, Southampton Buildings,
London.
THOS. SILVER. (L.S.)