IMPROVEMENTS IN LAMPS AND LANTERNS
Year: 1868

page_text: LETTERS PATENT to John Henry Irwin, of Chicago, in the County of
Cook, and State of Illinois, United States of America, for the
Invention of "IMPROVEMENT
T
Sealed the 25th March 1869, and dated the 29th September 1868.
PROVISIONAL SPECIFICATION left by the said John Henry Irwin at
the Office of the Commissioners of Patents, with his Petition, on the
29th September 1868.
I, JOHN HENRY IRWIN, of Chicago, in the County of Cook, and State
of Illinois, United States of America, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN LAMPS AND LANTERNS," to be as
follows:-
My Invention has reference to lamps and lanterns in which an
artificial draught is produced by the ascending current of air from the
flame, and consists in the mode or modes of constructing lamps and
lanterns herein-after stated.
The burner of the lamp or lantern is similar to those in use in lamps
in which kerosene oil is burned, but having at the top of the wick tube

page_text: projections to regulate the motion and direction of the air as it comes in
contact with the flame. This burner is covered by a hollow cone or
deflector of the kind commonly used, which deflector fits on to the
upper part of an air chamber, which forms a communication between an
air tube or tubes extending to the top of the lamp and the burner. A
perforated plate with a domed top rests on the deflector and supports a
globe or hollow vessel. The form of the plate and its diameter in
relation to that of the said air chamber are adapted to prevent any
undue rush of air into the globe, either laterally or from underneath the
plate. The top of the globe fits into a cap, over which (but with an air
space intervening) is fitted a dome leading into a vertical tube com-
municating with the upper part of the air tube or tubes. By this
arrangement a circulation of air is maintained from the burner upwards
through the globe, and downwards through the air tubes to the air
chamber communicating with the burner, air also being admitted at the
top of the globe as required. The globe is fitted to the dome at top and
to the perforated plate at bottom in such a manner as to admit of its
being removed when required. The number and arrangement of the air
tubes may be varied so as to adapt them for the construction of lamps
and lanterns for different uses, and they will serve as guards for the
globe, or other guards may be applied in the form of rings encircling
the globe.
In the construction of lamps to be used in houses or in situations not
exposed to external currents of air, the globe or hollow vessel and the
perforated plate may be dispensed with.
In some lamps the air tubes may be made to form part of the frame
of the lamp. When only one tube is used it may be bent over so as to
form the requisite communication with the aforesaid dome at the upper
part of the lamp.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-ninth day of September, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said John Henry Irwin, Her special licence
that I, the said John Henry Irwin, my executors, administrators, and
assigns, or such others as I, the said John Henry Irwin, 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 LAMPS AND LANTERNS," upon the condition (amongst others) that
I, the said John Henry Irwin, 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.
NOW KNOW YE, that I, the said John Henry Irwin, 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, that is to say :-
My said Invention relates chiefly to lamps and lanterns in which an
artificial draught is produced by the ascending current of air from
the flame.
The first part of my said Invention relates to the combination with
the burner of a lamp or lantern of a tube or tubes so constructed and
arranged that a current of air generated by the flame is caused to
impinge upon the flame and promote a more perfect combustion,
particularly from oils which are rich in carbon.
The second part of my said Invention relates to the combination with
the burner and with the conducting device, above mentioned, of a
globe or its equivalent which serves to make the operation more
perfect, and which may also serve to protect the flame from external
currents of air.

page_text: The third part of my said Invention consists in the combination
with the burner and with the conducting device, above mentioned, of a
chamber placed near the base of the burner, which chamber receives the
air from the conducting tubes and discharges it by means of suitable
appliances upon the flame.
The fourth part of my said Invention consists in the arrangement of
the conducting tubes, above mentioned, in such a manner as to form
guards for the protection of the globe or its equivalent when such
globe or its equivalent is used.
The fifth part of my said Invention consists in the construction and
combination with the conducting tubes, above mentioned, of additional
guards to protect the globe when one is used.
The sixth part of my said Invention consists in the combination of the
burner, the conducting tubes above mentioned, a globe or its equivalent,
and a horizontal plate or a plate inclining upward towards the center and
perforated with small holes for the regulation of the admission of external
air, as herein-after more fully set forth.
The seventh part of my said Invention consists in the combination
with the burner, the conducting tubes, and the globe or its equivalent of
a device which allows the globe or its equivalent to be raised up from
its seat without disconnecting it from the conducting tubes, as herein-
after set forth.
The eighth part of my said Invention consists in the formation of the
sides of the cap of the lantern with an inwardly and upwardly pro-
jecting flange at the top for the purpose of deflecting upward any current 2
of air which may enter at that point from the outside atmosphere.
The ninth part of my said Invention consists in the combination with
the sides of the cap of the lantern of a top plate or dome larger in
diameter than the sides of the cap for the purpose of causing a downward
motion of the lantern to throw additional air into the conducting tubes,
and thus keep up a supply of air to the flame.
The tenth part of my said Invention consists in forming the sides of
the cap of the lantern with projections made in one piece with it to
unite it with the top of the cap or dome without the use of solder, and
securing these projections in holes in the dome as set forth.
3

page_text: plate F has a rim or flange b turned upward at its outer edge to receive
the base of the globe G which is made to fit removably within it, and
the top of the said globe is made to fit removably into the sides H of the
cap of the lantern. These sides H rise vertically or nearly so to within
a very short distance from the top, where they are contracted in such a
manner as to deflect upward any air which may enter between them and
the dome I or top plate of the cap. This part H is formed of a single
piece of sheet metal without solder, and with it in the same piece and
without solder are formed projections c, which though represented in
Figure 4 in a horizontal position (as first formed) extend upward when
the construction is complete, and small tenons d formed on their upper
ends extend through holes e in the dome I, and are riveted or bent over
to secure them in said plate without solder. The dome I of the cap is
made somewhat bell-shaped, as shown, and is larger in diameter than the
cylindrical portion H of the cap for the purpose of gathering the air
when the lantern is moved downward, and thereby securing the certainty
of the flame being fully supplied with air during the downward motion
of the lantern. The dome I has a hole in its center and is directly
connected to the tube J so as to give a current of air up through said
tube J into the tubes C with which it connects, as shown. The mode
represented in Figures 1 and 2 of connecting the dome I to the tube
or pipe J is by means of a short tube or flange f, which is either firmly
connected to or formed with the dome I, and this short tube or flange f
is formed with a screw thread in it which fits upon a corresponding
screw thread formed upon the pipe J. When thus constructed the globe
may be raised up from the burner by screwing the dome I upward on
the pipe J, and by then withdrawing said globe downward from the cap
or shell I it may be removed entirely from the lantern when occasion
may require. In the construction represented in Figure 6 instead of
the dome I being attached to the pipe J by a screw it is fitted to slide
upon it, and is in that case kept down in position by a spiral spring g
which is placed upon the tube J for that purpose. When this latter
construction is adopted the lower end of the tube J should be swaged
out to form a slight flange, as shown in Figure 6, to prevent the dome I
from being forced off the end of the said tube by the spring. The
tubes C, C, should be arranged in pairs on each side of the lamp or
lantern, and so formed and arranged as to form guards to protect the
globe when a globe is used. A single pair of these tubes may generally
be found sufficient, though for street lamps or other lanterns of that

page_text: class perhaps a larger number may be necessary. For the common hand
lantern I prefer a single pair of these tubes, and for the further pro-
tection of the globe I attach to said tubes the horizontal guards K, which
I connect together with half sleeves h, h, which are made to fit upon the
pipes C in such a manner as to be removable from the said pipes, so
that these horizontal guards can be taken off when desired to allow the
globe to be removed, or for other purposes. L is a bail attached to the
tubes C, C, at the top. The construction described and represented in
the Drawings is particularly adapted for use as a portable or hand
lantern, and may also be used as a lamp, but when it is designed for use
as an ordinary house lamp or in places where it is not exposed to external
currents of air the globe G and the plate F may well be dispensed with,
as the conducting tubes will without their aid supply a sufficient-
quantity of air to produce good combustion, because the current pro-
duced by the heated air ascending into the tube J will produce a
sufficient descending current through the tubes C, C, for that purpose.
In street lamps having the ordinary form of two pyramids joined at the
base the construction may be so modified as to make the pipes C, C, form
the principal parts of the corner pieces of the frame, proper pieces being
attached to them to hold the glass. For a common hand lamp not
exposed to currents of air one of the tubes C, C, shown in Figures 1
and 2 may for convenience be dispensed with, and so also might the
part H of the cap, in which case it might be advisable to make one or
two holes, say one-eighth of an inch in diameter, in the sides of the
pipe J. Of course when no globe is to be used no device by which the
dome I can be raised up on the pipe J is necessary, and it may also
when no globe is to be used be advisable to make the dome I more in
the form of a common funnel. When only one of the tubes C is used it
may be bent over so as to also form the tube J. A hood may also in
some cases perhaps serve the purpose of the tube J.

page_text: Third. The combination of the burner D, tubes C and J, and
chamber B, sublantially as herein-before set forth.
Fourth. The arrangement of the conducting tubes C, C, in combination
with the globe G in such a manner that the said tubes shall form guards
for the protection of the said globe, as herein-before set forth.
Fifth. The combination of the tubes C, C, and one or more of the
guards K, substantially as herein-before set forth.
Sixth. The combination of the tubes C and J, burner D, globe G or its
equivalent, and plate F, substantially as herein-before set forth.
Seventh. The combination of the burner D, conducting tubes C and J,
globe G or its equivalent, and a device which allows said globe to be
raised up from its seat, substantially as herein-before set forth.
Eighth. The combination of the part H formed with an inward
inclination at the top with the dome I, substantially as herein-before
set forth.
Ninth. The combination of the part H with the dome I having a
larger diameter than the part H, substantially as herein-before set forth.
Tenth. The combination of the dome I and the part H having
projections c formed in one piece with it to unite said parts H and I,
substantially as herein-before set forth.
In witness whereof, I, the said John Henry Irwin, have heretofore
set my hand and seal, this Tenth day of March, A.D. One
thousand eight hundred and sixty-nine.