IMPROVEMENTS IN LAMPS FOR BURNING PETROLEUM AND OTHER MINERAL OILS"
Year: 1873

page_text: LETTERS PATENT to John Thomas, of Cumberland Street, Barnsbury,
in the County of Middlesex, Lamp Manufacturer, and Amos
Piggott, of Westfield, Retford, in the County of Nottingham,
Signal Inspector, for the Invention of "IMPROVEMENTS IN LAMPS FOR
BURNING PETROLEUM AND OTHER MINERAL OILS"
PROVISIONAL SPECIFICATION left by the said John Thomas and
Amos Piggott at the Office of the Commissioners of Patents, with
their Petition, on the 14th June 1873.
We, JOHN THOMAS, of Cumberland Street, Barnsbury, in the County
of Middlesex, Lamp Manufacturer, and AMOS PIGGOTT, of Westfield,
Retford, in the County of Nottingham, Signal Inspector, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN LAMPS FOR
BURNING PETROLEUM AND OTHER MINERAL OILS," to be as follows:-
This Invention consists in certain improvements in the construction
of lamps for burning petroleum and other mineral oils, and whereby the

page_text: necessity for a glass chimney is dispensed with, and the liability to failure
in burning is avoided.
This Invention is especially applicable to the construction of lamps to
be employed as railway and marine "signal lamps."
The lamp is provided with an ordinary reservoir for the oil, and above
which is placed a table or platform supported so as to allow a free
current of air to pass between the same and the reservoir. The table or
platform is pierced in the centre to allow the burner screw to pass freely
through the same, a small space being left between the burner and the
table or platform for the double purpose of admitting air to the flame,
and of insulating the table or platform from the burner so as to prevent
the heat being communicated from the former to the latter, and thence
to the oil.
Above the table and surrounding the flame is placed a case formed
partly of metal and partly of glass, and constructed of any suitable shape.
Such case is supported on three or more points, and fits loosely over the
top of the table or platform, a space being thereby left between the
same for the purpose of admitting air, and also to insulate the case so as
to prevent the heat being conducted therefrom too freely to the table or
platform, and thence to the oil reservoir.
In the sides of the case are fixed suitable glasses or lenses to allow of
the passage of light from the burner, and at the bottom of the case is
fixed a metallic cap or dome such as is ordinarily used in lamps for
burning mineral oils. In the bottom of the case is a row of small
apertures in close proximity to the lower part of the glasses for the
purpose of admitting a current of air, and to cause the same to pass over
the inner surface of the glasses, thereby preserving the same free from
moisture. Upon the upper portion of the case is placed a cover or top
supported upon three or more points, a space being left between the
same and the case for the purpose of allowing a current of air to pass
through, and also to prevent the heat of the chimney passing down to
the case and thence to the oil reservoir. In and upon the said cover is
fixed an upright cone or taper tube, from the top of which and extending
downwards to within a short distance of the flame is fixed a metal
chimney for the purpose of carrying off the heat and products of com-
bustion, and above the top of the chimney but raised considerably above
the same is placed a cap for the purpose of preventing any downward

page_text: draught being projected upon the flame. The chimney is fixed as before
mentioned for the purpose of preventing the conduction of its heat too
readily to the cover and case. On the exterior of the cone or taper tube
and springing from the same is placed a tubular case to act as a pro-
tector to the top or exit end of the chimney. The top of the tubular
case is closed, but at the upper part of the sides thereof are a number of
small perforations for the purpose of regulating the escape of the heated
air, and to prevent the wind or draught from blowing too freely upon the
chimney.
On the outside of the last mentioned case is a wind guard to give
additional protection to the chimney, and upon the top of the lamp is a
metal dome or shield for the purpose of preventing the light from being
affected by the wind, and also of causing it to burn steadily.
The lamp so constructed as herein-before mentioned may be placed
within a case or lantern furnished with the necessary coloured lenses for
the purposes of signalling.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Thomas and Amos Piggott in the Great
Seal Patent Office on the 12th December 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
THOMAS, of Cumberland Street, Barnsbury, in the County of Middlesex,
Lamp Manufacturer, and AMOS PIGGOTT, of Westfield, Retford, in the
County of Nottingham, Signal Inspector, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourteenth day of June, in the year of
our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said John Thomas and Amos Piggott,
Her special licence that we, the said John Thomas and Amos
Piggott, our executors, administrators, and assigns, or such others as
we, the said John Thomas and Amos Piggott, our executors, ad-
ministrators, 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,

page_text: and vend, within the United Kingdom of Great Britain and Ireland,
the Channel Islands, and Isle of Man, an Invention for " IMPROVE-
MENTS IN LAMPS FOR BURNING PETROLEUM AND OTHER MINERAL OILS," upon
the
condition (amongst others) that we, the said John Thomas and Amos
Piggott, our executors or administrators, by an instrument in writing
under our, 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 we, the said John Thomas and Amos Piggott,
do hereby declare the nature of our said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, reference being had to the
Drawings hereunto annexed, and to the figures and letters marked
thereon, that is to say:
-
Our said Invention consists in certain improvements in the con-
struction of lamps for burning petroleum and other mineral oils, and
whereby the necessity for a glass chimney is dispensed with, and the
liability to failure in burning is avoided.
Our said Invention is especially applicable to the construction of
lamps to be employed as railway and marine "signal lamps."
The lamp is provided with an ordinary reservoir for the oil, and above
which is placed a table or platform supported so as to allow a free
current of air to pass between the same and the reservoir. The table or
platform is pierced with an aperture in the centre thereof to allow the
burner to pass freely through the same, a small space being left between
the burner and the table or platform for the double purpose of admitting
air to the flame and of insulating the table or platform from the burner
so as to prevent the heat being communicated from the former to the
latter, and thence to the oil.
'
A case formed partly of metal and partly of glass and of any suitable
shape is placed over the last mentioned table or platform and supported
on the upper part thereof by three or more points, a space being thereby
left between the same for the purpose of admitting air, and also to
insulate the case so as to prevent the heat being conducted therefrom too
freely to the table or platform and thence to the oil reservoir,

page_text: In the sides of the case are fixed suitable glasses or lenses to allow of
the passage of light from the burner, and at the bottom of the case is
fixed a metallic cap or dome, such as is ordinarily used in lamps for
burning mineral oils. In the bottom of the case is a row of small
apertures in close proximity to the lower part of the glasses for the
purpose of admitting a current of air, and to cause the same to pass over
the inner surface of the glasses, thereby preserving the same free from
the effects of the condensation of aqueous moisture. Upon the upper
portion of the case is placed a cover or top supported upon three or more
points, a space being left between the same and the case for the purpose
of allowing a current of air to pass through, and also to prevent the heat
of the chimney passing down to the case and thence to the oil reservoir.
In and upon the said cover is fixed an upright cone or tapered tube,
from the top of which and extending downwards to within a short
distance from the flame is fixed a metal chimney for the purpose of
carrying off the heat and products of combustion, and above the top of
the chimney, but raised considerably above the same is placed a cap for
the purpose of preventing any downward draught being projected upon
the flame. The chimney is fixed as before mentioned for the purpose of
preventing the conduction of its heat too readily to the cover and case.
On the exterior of the cone or tapered tube and springing from the same
is placed a tubular case to act as a protector to the top or exit end of the
chimney. The top of the tubular case is closed, but at the upper part of
the sides thereof are a number of small perforations for the purpose of
regulating the escape of the heated air, and to prevent the wind or
draught from blowing down the chimney.
On the outside of the last mentioned case is a wind guard to give
additional protection to the chimney, and upon the top of the lamp is a
metal dome or shield for the purpose of preventing the light from being
affected by the wind, and also of causing it to burn steadily.
In order to prevent the conduction of heat the several points of
contact between the respective parts of the lamp are as far as practicable
made by means of suitable non-conducting materials.
The lamp so constructed as herein-before mentioned may be placed
within a case or lantern furnished with the necessary colored lenses for
the purpose of signalling.
We will now refer to the accompanying Drawings from which the
nature of our said Invention will be more clearly understood.

page_text: Figure 1 is a vertical sectional view of the lamp shewing the details of
construction.
Figure 2 is a plan of the table or platform, and Figure 3 is an
external elevation of the lamp. The same letters of reference indicate
similar parts in the several Figures.
A is the reservoir or cistern; B, the body of the burner; b, the burner
tube; C is the table or platform; c, the feeder screw; D, the metal and
glass case; d, the bottom of the case; d, the cap or dome of the burner;
E is the top or cover of the case; F, the chimney; f, the cap over the
same; G is the cone for supporting the chimney; H, the outer cone or
tubular case; h, the perforations for the escape of the products of com-
bustion; h, air space for preventing smoke and keeping the lamp cool;
I is the wind guard; K, the top shield or cover.
Having thus described and ascertained the nature of our said Invention,
and in what manner the same is to be performed, we would observe in 1
conclusion that what we consider novel and original and therefore claim
as constituting the Invention secured to us by the said herein-before in
part recited Letters Patent are,-
First. The admission of a regulated supply of air within the case of
the lamp above the flame for the purpose of preventing smoke, and 2
keeping the lamp cool by the means and in the manner substantially
herein-before set forth.
And, secondly. The combination of parts and mechanism sub-
stantially as and for the purposes herein-before described and set
forth.
In witness whereof, I, the said John Thomas, on behalf of
myself and the said Amos Piggott, have hereunto set my hand
and seal, this Twelfth day of December in the year of our
Lord One thousand eight hundred and seventy-three.
T THOMAS
herein-before set forth.
And, secondly. The combination of parts and mechanism sub-
stantially as and for the purposes herein-before described and set
forth.
In witness whereof, I, the said John Thomas, on behalf of
myself and the said Amos Piggott, have hereunto set my hand
and seal, this Twelfth day of December in the year of our
Lord One thousand eight hundred and seventy-three.
J. THOMAS
TRYERS