IMPROVEMENTS IN THE CONSTRUCTION OF DRAUGHT TUBES OR GLOBES DESIGNED TO BE USED AS A SUBSTITUTE FOR THE GLOBES ORDINARILY PLACED ON GAS BURNERS
Year: 1871

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine,
Lake, & Co., Patent Agents, Southampton Buildings, London, for
the Invention of "IMPROVEMENTS IN THE CONSTRUCTION OF DRAUGHT
TUBES OR GLOBES DESIGNED TO BE USED AS A SUBSTITUTE FOR THE GLOBES
ORDINARILY PLACED ON GAS BURNERS."-A communication from abroad
by Toussaint Trudeau, of Ottawa, Canada, Deputy Minister of
Public Works.
PROVISIONAL SPECIFICATION left by the said William Robert Lake
at the Office of the Commissioners of Patents, with his Petition, on
the 4th May 1871.
I, WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co.,
Patent Agents, Southampton Buildings, London, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN THE CONSTRUCTION OF

page_text: DRAUGHT TUBES OR GLOBES DESIGNED TO BE USED AS A SUBSTItute for the GLOBES
ORDINARILY PLACED ON GAS BURNERS," a communication, to be as follows:-
The object of my Invention is to obtain a tranquil gas flame with
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illuminating gas consumed through vertical flat flame burners.
accomplish this object I use any of the known good vertical flat flame
burners fitted to any well made gas fixture, having wide and free
passages, and allowing the gas to flow smoothly to the burner. Over
the burner I apply a tube or globe having a wide unobstructed opening
throughout, and with its top and bottom diameters of certain adjusted
proportions, the tube or globe being of such limited height that I can
The flame emitted
avail myself of the forms of globes at present in usc.
from a naked gas jet unassisted by a draught apparatus burns with a
flickering up and down movement very fatiguing to the eyes, and but
little improvement is observed when a globe or bell glass of the form
made hitherto for use over vertical flat flame burners is placed on the
This defect is
light, the flame then oscillating from side to side.
attributed to the fact that these globes as at present constructed have
lower openings of only about two inches diameter or have an otherwise
obstructed air duct.
The result of using my improved form of tube or globe is that the
flame is enveloped in a smooth and gently ascending current of air,
which causes the light to burn steadily without flickering or oscillation.
The additional advantages arising from the use of my apparatus are,-
1st. That in an ordinary, quiet, indoor atmosphere, a tranquil light is
obtained at very low and consequently economical pressures.
2nd. The action of the air is so controlled that the combustion of the
noxious part of the gas flame is more complete.
3rd. The wide unobstructed lower opening allows the free passage of
light in the direction most required, that is to say, downward, and affords
facility for lighting without soiling the globe.
4th. The limited height, combined with the wide upper opening
obviates almost entirely the risk of breakage through the overheating
and unequal expansion of the globe or tube when the same is made of
glass.
For general use I give to my draught tubes or globes the following
dimensions, viz., diameter of lower opening 4½ inches, diameter of upper

page_text: opening 6 inches, height 34 inches, and I curve the sides somewhat,
but these proportions are susceptible of considerable variation. Great
care however is necessary in varying these proportions to make them
such as will produce the exact draught needed. To obtain a proper
draught when it may be desired to deviate from the above dimensions
I first select a diameter of lower opening, which for practical purposes
may be limited to from 2 to 7 inches. The height of the globes or
tubes may be equal to one and a half times the diameter of the lower
opening, as a maximum, and to one half of said diameter as a minimum,
provided said maximum be not more than 7 inches, and said minimum bę
not less than 2 inches, but I very much prefer as more efficient and
economical a medium height equal say to ¾ of the diameter of the lower
opening, provided said medium height is not less than 3 inches.
I then make a model of the proposed draught tube giving it the
breadth of the lower opening, and height selected with an upper opening
threc inches wider than the lower opening, taking care that no part of
such model globe above the flame be made less than 6 inches in diameter.
The model is then placed over a good vertical flat flame gas burner
consuming say 4 or 5 fect of gas per hour at a pressure of about of an
inch of water in the position intended for use. The result is that an
ascending current is created whose force may be reduced by diminishing
the area of the upper opening of the globe or tube.
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To ascertain the diameter of the upper opening necessary to produce
the exact draught required I use a series of plates, each plate having a
circular aperture cut in its centre, the said apertures increasing in
diameter as follows, the smallest aperture is one inch in diameter, the
second 1 inches, the third 1 inches, and so on. I place these plates
one after the other on the top of the model globe or tube, commencing
with the plate having an opening of one inch in diameter. This small
opening does not allow a proper current of air to pass through the tube
or globe and consequently the flame flickers and rolls, but as I exchange
the plates, gradually enlarging the upper opening, I find an improvement
is effected until at length a diameter is found which prevents the rolling
and flickering.

page_text: I obtain the best results by placing the lower edge of my draught
tubes or globes opposite the lower part of the flame, either at or near
the level of the top of the burner. The effect of very low globes or tubes
is improved by their being raised above the level of the top of the
burner.
When measuring the diameter of any of my globes or tubes the lower
portion of which diverges slightly in a downward direction, I take the
narrow part of the tube or globe at the point where such divergence
commences as the diameter of the lower opening. In cases of globes or
tubes extending below the top of the burner I adopt the narrowest
diameter of the tube or globe in the immediate vicinity of the top of the
burner as the diameter of the lower opening.
My draught tubes or globes may be manufactured of glass (clear or
ground) porcelain, thin sheet metal, or other suitable material, and
ornamented according to fancy.
I may also make my improved tubes or globes of paper or pasteboard,
and such tubes or globes will be highly advantageous where glass and
other globes or tubes would be too costly or liable to breakage. I prefer
that the tubes or globes should be circular as seen from the top, but they
may be oval if desired. The burner should be in the centre of the
opening of the globe or tube, although it may be placed out of the
centre without inconvenience.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Robert Lake in the Great Seal Patent
Office on the 3rd November 1871.
.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London, send greeting.
2
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of May, in the year of a
our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said William Robert Lake, Her special licence'
that I, the said William Robert Lake, my executors, administrators,

page_text: and assigns, or such others as I, the said William Robert Lake, my
exccutors, 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 THE CONSTRUCTION OF DRAUGHT TUBES OR GLOBES DESIGNED TO BE USED AS A
SUBSTITUTE FOR THE GLOBES ORDINARILY PLACED ON GAS BURNERS," a commu-
nication to me from abroad by Toussaint Trudeau, of Ottawa, Canada,
Deputy Minister of Public Works, upon the condition (amongst others)
that I, the said William Robert Lake, 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 William Robert Lake, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement, reference being had to the accompanying
Drawing forming a part of this Specification :-
The object of my Invention is to obtain a tranquil gas flame with
illuminating gas consumed through vertical flat flame burners. To
accomplish this object I use any of the known good vertical flat flame
burners fitted to any well made gas fixtures having wide and free
passages, and allowing the gas to flow smoothly to the burner. Over
the burner I apply a tube or globe having a wide and unobstructed
opening throughout with diameters at the top and bottom of certain
adjusted proportions, the tube or globe being of such limited height that
I can avail myself of the elegant forms of the globes at present in
usc. The flame emitted from a naked gas jet unassisted by a draught
apparatus burns with a flickering up and down movement very fatiguing
to the cycs, and but very little improvement is observed when a globe
or bell glass of the form hitherto made for use over ordinary vertical
flat flame burners is placed on the light, the flame then oscillating from
side to side. This defect is attributable to the fact that these globes as

page_text: For general and economical use I give to my draught tubes or globes
the following medium dimensions which should not be very much
departed from :-Diameter of lower opening 4 to 5 inches, diameter of
upper opening 6 to 7 inches, height 3 to 4 inches, and I curve the sides
somewhat as shown in Figure 1. Globes and tubes with small lower
openings of 2 and 3 inches, or even of 3½ inches diameter should be
used only with small burners which consume say 2 or 3 cubic feet of
gas per hour. Larger burners which consume 4 or 5 feet or more per
hour are better controlled by globes having larger lower openings.
The best and most economical use of the gas is obtained when the
draught is at its lowest point consistent with steadiness of light, that is
to say, when the flame is on the verge of flickering and yet does not
flicker. This minimum draught is obtained sufficiently for practical
purposes by the use of globes or tubes of about three or four inches in
height.
In order to make globes or tubes ensuring steady light and economy
of gas I make a model of the proposed globe or draught apparatus,
giving it the breadth of lower opening and height selected, and the
outline of any of the examples given in Figures 5 to 24 with an upper
opening three or four inches wider than the lower opening, taking care
that no part of such model globe above the flame be made less than six
inches diameter. The model is placed over a good vertical flat flame
gas burner consuming, say, four, five, or six feet of gas per hour at a
pressure of about 3, of an inch of water in the position shewn by
The result is that an
Figure 1 or in the position intended for use.
ascending current of air is created. If this ascending current be too
strong it will produce such active combustion as to diminish the flame,
but its force may be reduced by diminishing the area of the upper
opening of the globe or tube.
To ascertain the diameter of upper opening necessary to produce the
exact draught required, I use a series of plates, each plate having a
circular aperture cut in its centre and increasing in diameter by fourths
of inches, the smallest aperture being one inch in diameter the second
inches, the third 1½ inches, and so on. These I place one after the
other on the top of the model globe or tube, commencing with the plate
having an opening of one inch in diameter. This small opening does not
admit of a proper current of air passing through the tube or globe, and
1

page_text: consequently the flame flickers and rolls, but as I exchange the plates,
gradually enlarging the upper opening, I find an improvement is effected,
until at length a diameter is found which prevents the rolling and
flickering. These trials should be repeated with pressure on the gas
varying within the ordinary practicable limits.
I then make a second model corrected to the diameter of upper
opening thus obtained, and I repeat the experiment with the plates
until a satisfactory draught is produced. I obtain the best results by
placing the lower edge of my draught tubes or globes opposite the lower
part of the flame either at or near the level of the top of the burner.
The effect of very low tubes or globes is improved by their being raised
above the level of the top of the burner, as shown by Figure 2.
When measuring the diameter of any of my globes or tubes the lower
portion of which diverges slightly in a downward direction, as shewn in
Figures 9, 10, and 12, I ignore this divergence and take the narrow
part of the tube or globe at the part where such divergence commences
as the diameter of the lower opening. With tubes diverging upwards
in the form of a trumpet, as in Figures 12, 15, and 16, the dimensions
of the upper opening should not be taken at the extreme edge of the
lip of the globe, but at the greatest diameter which would be obtained
if the general direction of the sides should be continued to the full height
of the tube.
In cases of globes or tubes extending below the level of the top of the
burner, as shown by Figure 4, I adopt the narrow diameter of the
tube or globe nearest the top level of the burner as the diameter of the
lower opening.
The force of draught is slightly increased when my globes or tubes
are continued downwards to any depth within three inches below the
level of the top of the burner, and it is more certain that the steadiness
of the flame will not be interfered with by this extension, if the same
be made wider than the diameter of the globe or tube at the level of the
top of the burner, as shewn, for example, by Figure 4. Any design
for a draught tube or globe or any form of curve at the top or bottom
whereby the flame would be liable to approach within one inch of the
tube or globe should be rejected.
My draught tubes or globes may be manufactured of glass (clear,
ground, or colored) porcelain, paper, pasteboard, thin sheet metal, or

page_text: other suitable material, and ornamented according to fancy. When
made of paper or pasteboard the globes or tubes should not be higher
than about four inches, and should have wide openings of not less than
four to five inches diameter at the bottom and seven to eight inches at
the top. I prefer the circular form as seen from the top, but they may
be of oval or polygonal shape if so desired. The burner should be in the
centre of the opening of the globe, although it may be placed out of the
centro without inconvenience when the globes or tubes are made of glass
or other.incombustible material.
It should be stated that the vibration of gas light is not only due to
defective combustion of the gas, but is often traceable to badly formed
elbows, or an otherwise obstructed passage through the pipe, which
prevents the unimpeded flow of the gas to the burner. For this reason
I prefer applying my draught tubes or globes to gas fixtures composed
of wide pipes, properly constructed elbows, and good burners, such as
are shewn by Figure 1. My draught tubes or globes may also bo
applied with advantage to burners known as economical burners, that
is to say, burners fitted with perforated plates or other obstructions,
reducing the pressure of the gas as it issues from the burner, provided
said pressure be not reduced much below good ordinary working limits.
In Figure 1, A is the pipe conveying the gas to the burner; B, the
burner holder; C, a flat flame burner, say, a fish-tail or a bats-wing;
D, D, a gallery or supporter made with three or four arms and upright
pins P, P; E, E, the draught tube or globe resting on the gallery D, D,
and retained in position by the pins P, P.
In Figure 2, B is a short burner holder such as may be used when
applied to gas fixtures of ordinary good make and workmanship, and
E, E, the draught tube or globe.
When it is required to apply my tubes or globes to gas fittings not
possessing the above advantages, but on the contrary offering a too
contracted passage for the gas in close proximity to the flame or having
badly formed elbows, I use a longer burner holder as shewn by Fin
Figure 3. The long burner holder F has the effect of quieting the gas,
forming, as it does, a reservoir in which the gas after its passage through
the contracted pipes or narrow sharp elbows may become to some extent
tranquilized.
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page_text: The lower edge of my globes or tubes may be turned outwardly as
in ordinary globes, and as shewn by Figures 14 and 16, and may be
supported by galleries fitted with binding screws as in galleries now in
general use.
Having thus fully described the said Invention as communicated to 5
me by my foreign correspondent, I wish it understood that I do not
claim the gas pipe A, the burner holders B or F, the burner C, nor the
gallery D, D, but I claim the improvements in the construction of
draught tubes or burners as herein set forth.
In witness whereof, I, the said William Robert Lake, have herc- 1
unto set my hand and seal, this Second day of November, in the
year of our Lord One thousand eight hundred and seventy-one.
Witness,
EDWARD C. JACKSON.
W. ROBT, LAKE. (L.S.)