IMPROVEMENTS IN THE MANUFACTURE OF LAMPS
Year: 1856

page_text: LETTERS PATENT to François Donny, Professor of Chemistry, of the City
of Ghent, in the Kingdom of Belgium, for the Invention of "IMPROVEMENTS
IN THE MANUFACTURE OF LAMPS."
Sealed the 29th May 1857, and dated the 18th December 1856.
PROVISIONAL SPECIFICATION left by the said François Donny at
the Office of the Commissioners of Patents, with his Petition, on the
18th December 1856.
I, FRANÇOIS DONNY, Professor of Chemistry, of the City of Ghent, in the
Kingdom of Belgium, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE MANUFACTURE OF LAMPS," to be as follows:-
My Invention of improvements in the manufacture of lamps relates to a
novel construction of lamp for illuminating purposes, such lamps being
intended to burn certain oils and essences which are sold at a low price, and
which have not hitherto been successfully applied to that purpose, as when
introduced into any of the ordinary lamps they either produce a considerable
amount of smoke, or cause a deposit of a crust of solid unconsumed matter,
upon various parts of the lamp. The oil which will probably be found most
advantageous for consumption in my lamp is heavy coal tar oil (dead oil):
In order to prevent this oil from smoking when consumed in the lamp,
I introduce into the interior of the flame a jet of air by means of a pipe,

page_text: through which the air is forced by means of bellows or any other suitablo
apparatus. The quantity of air supplied must be regulated by means of a
cock, according to the size of the lamp and the development of the flame.
In order to obtain regular combustion and prevent the deposit of solid
matter, I employ a peculiar construction of burner; in which the combustion
of the oil is obtained without the employment of a wick, the oil to be con-
sumed being contained in a small circular or annular vessel, through the
centro of which passes a pipe for supplying a blast of air to the flame. The oil
is supplied to this vessel from underneath by a pipe, situate at the side of
the air pipe, and supplied by-means of a reservoir situate above at the same
level, or by any other suitable means. An annular space is provided round
the outside of the oil vessel for the reception of any oil which may overflow,
this waste oil being conveyed away through a pipe below to any suitable
receptacle. The flame is prevented from touching the sides of the oil vessel by
means of a ring of wire gauze, placed over or adapted to the burner of the
lamp. It is desirable to surround the flame with a short metal chimney or
deflector, in order to prevent the external currents of air from acting
injuriously on the flame, and the better to concentrate the products of com-
bustion.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said François Donny in the Great Seal Patent Office on tho
18th June 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, 'I, FRANÇOIS
DONNY, Professor of Chemistry, of the City of Ghent, in the Kingdom of
Belgium, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighteenth day of December, in the year of our Lord
One thousand eight hundred and fifty-six, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, giver and grant unto me, the said
François Donny, Her special license that I, the said François: Donny, my
executors, administrators, and assigns, or such others: as I, the said François
Donny, my executors, administrators, and assigns, should at any timo. 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 MANU-

page_text: FACTURE OF LAMPS," upon the condition (amongst others) that I, the said
François Donny, by an instrument in writing under my hand and seal, should
particlilarly 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 François Donny, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawing hereunto annexed, and to
the letters and figures marked thereon (that is to say):-
My Invention of improvements in the manufacture of lamps relates to a
novel construction of lamp for illuminating purposes, such lamps being
intended to burn certain oils and essences which are sold at a low price, and
which have not bitherto been successfully applied to that purpose, as when
introduced into any of the ordinary lamps they either produce a considerable
amount of smoke, or cause a deposit of a crust of solid unconsumed matter
upon various parts of the lamp.
The oil which will probably be found most advantageous for consumption
in my lamp is heavy coal tar oil (dead oil). I will thereforo take it as an
example in the following description of my improvements in the manufacture
of lamps.
The lamp wbich I am now about to describe thereforo fulfils two conditions,
viz-first, it allows of the consumption of heavy coal tar oil without tho
production of smoke; second, the functions of this lamp are not influenced
by the impurities which may be produced by the oil in burning; also, the
flame, whatever may be the developement given to it, produces a regular
light, that is to say, that after ten or twelve hours combustion the light will
have lost none of its intensity, and that during all that time the lamp will
not require any cleaning.
These results are obtained by constructing the lamp in the following
manner: In order to prevent the oil from smoking when consumed in the
lamp, I introduce into the interior of the flame a jet of air by means of a
pipe, through which the air is forced by a bellows or any other suitable
apparatus. The quantity of air supplied to the burner may be regulated by
a cock, and the quantity must depend upon the size of the lamp and the
developement of the flame. If too much air be supplied to the flame the
combustion will be too intense, and the flame will lose much of its illuminating
property and be more suitable for heating purposes. If, on the other hand,

page_text: too small a quantity of air be supplied, a portion of the carbon will escape.
unconsumed and the flame will become fuliginous.
In order to obtain regular combustion and avoid the formation of deposits,
on the lamp, I effect the combustion of the oil in a burner of a peculiar.
construction, and of which I will now proceed to describe the three essential
parts, viz: first, that in which the oil is set on fire; second, that part intended
for the elimination of those parts of the oil which, by reason of their impurity
or their composition, escape combustion, and run off under the form of a thick
black liquid; thirdly, that part intended to prevent the formation upon the.
burner of the lamp of deposits of lamp-black, similar to those which may
bo observed round the wick of a candle which has been suffered to burn
for a considerable time without snuffing.
Fig. 1 in the accompanying Drawing is a sectional view of the burner.
part of my improved lamp, in which the oil is burned without the intervention
of a wick, the oil being supplied to an annular chamber a, through the
centre of which the air to support combustion is supplied from below through
a pipe b, the oil being also supplied from below. through another pipe c, either.
by means of a reservoir above or by any other suitable means.
Purified oils of coal tar, oils such as benzole, camphine, or rectified naphtha,
will burn perfectly well by means of this simple arrangement; but when it
is required to employ therein. the oil known as heavy coal tar oil, or dead
oil, two inconveniences present themselves, viz:-first, the most imparo parts
of this oil will rise by a kind of capillary attraction over the sides of the
chamber or oil vessel, and will drip over, as shewn in the sectional view,
Fig. 2, by which means the outside of the oil vessel will be liable to catch
fire, which would considerably derange the operation of the lamp; secondly,
the flame of heavy tar oil being very fuliginous will quickly deposit at the
edges of the oil vessel a layer of lamp-black, which by its rapid accumulation
causes a serious inconvenience, as shown at Fig. 3.
The first of these inconveniences is prevented by making round the oil
vessel, where combustion takes place, a circular concentric compartment, as
shewn at d, d, Fig. 4, so as to provide an empty annular space between the
oil vessel and the outer wall of the compartment. The oil which runs over.
by capillary attraction will flow over into this annular space, and passing
through a pipe e will escape into a receptacle below.
The second inconvenience may be obviated by preventing the luminous
part of the flame from touching the outer sides of the oil vessel. This I
effect by adapting a ring of wire gauze g (shewn detached at Fig. 5) to the
outer circumference of the lamp, as shewn in Fig. 6. I also apply a small

page_text: metallic chimney cone or deflector h to the flame of the lamp, as shewn
at Fig. 6, in order to protect it from the action of currents of air.
The advantages obtained by this improved construction of lamp are the
production of a cheap light; a burner giving a light equal to twelve wax
candles will burn less than a gill of coal tar oil per hour, and as this oil is
exceedingly cheap the cost of burning it will amount to less than a farthing
per hour. Another advantage is the production of a very brilliant light with
a single burner, as it may be made to equal that of one hundred wax candles,
or even more.
Although my improved construction of lamp may be employed for many
purposes, it will be found most advantageous to employ it in works in which
steam engines or other motive power is in use, by means of which the lamp
may be easily supplied with a continuous current of air.
Having now described my Invention of "Improvements in the Manufacture
of Lamps," and the means of carrying the same into effect, I claim, as the
Invention secured to me by Letters Patent as aforesaid, the mode herein
described of arranging and constructing the various parts of lamps for burning
hydrocarbons, or heavy oils, or any mere modification of the same.
In witness whereof, I, the said François Donny, have hereunto set my
hand and seal, the Sixteenth day of June, in the year of our Lord
One thousand eight hundred and fifty-seven.