IMPROVEMENTS IN LAMPS
Year: 1874

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
“IMPROVEMENTS IN LAMPS."-A communication from abroad by Emile
Granier, Paris, France.
Sealed the 12th March 1875, and dated the 14th September 1874.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 14th September 1874.
:
I, ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN LAMPS," to be as follows
This Invention relates to improvements in lamps for burning mineral,
vegetable,.
, or animal oils. I make the burner cylindrical and of small
diameter in order that it shall not cast any shadow, it being also arranged
in such manner as to obtain the most perfect combustion from
inflammable liquids usually emitting smoke, and a disagreeable -odour
like petroleum of schist oils,

page_text: In the accompanying Drawing, A, Figure 1, is a metallic cap to which
air is admitted around its base B only. The cap A is fitted to slide on
the wick tube at C, in order that it may be adjusted in position to
regulate the admission of air at B as well as in regard to the flame, it
also enables it to be readily removed for the purpose of cleaning and
trimming the wick.
For some kinds of oils I may provide the burner with one or more
rows of holes or openings i for supplying air around the wick, and it
may be also at point V for increasing the air supply at the base of the
cap.
In the arrangement, Figure 2, which shows a section of a lamp, I
obtain still better results by perforating the whole surface of the cap as
at D except the top d, by which means a steady colorless flame is pro-
duced without smell and giving but little heat. This which
cap
bc
made either of perforated sheet metal or of wire gauze is of less
diameter than when unperforated as in Figure 1.
may
In some cases I apply at the top of the central air passage B of the
burner D a perforated or gauze cone L, or it may be of cylindrical or
inverted conical form according to the form of flame I desire to produce.
The cap may be made of platinum for the purpose of increasing the
brilliancy of the flame. With this cap D a pure colorless flame may be
obtained, without producing any smoke from liquids hitherto possessing
this objectionable quality.
A further advantage is that any kind of glass chimneys, whether of
cylindrical, conical, or other form, or a globe only, may be used to shelter
the flame. It is however preferable to use a glass chimney E having
one or more rows of holes at f, and contracted in diameter from P to Q,
while there may be a second row of holes fabove the flame, and the
chimney be further reduced in diameter from K to M. In this manner
a perfect combustion of the gases is ensured at same time that a more
intense flame is obtained without any increase in the consumption of
oil. As this burner is supplied with a sufficient amount of air for com-
bustion by the lateral openings, the air inlet B, Figure 1, which is
indispensable in the former case may be dispensed with, thereby enabling
the cap to be made of small diameter and of a form adapted for fixing
either to the wick tube or gallery G; Y is the body of the lamp; A,
tube enclosing the wick C; B, central wick tube for supplying air which

page_text: may be admitted either at B¹ or at the bottom of the lamp; H, rack for
adjusting wick; X, openings for admitting air around base of cap D; Z,
attachment to cap D to wick tube.
In Figure 3 the chimney is shown as supported either by a wire gauze
or perforated metal casing A, wherebý a much larger quantity of air
may be supplied to the flame.
The orifice of the cap may be made either larger, smaller, or of the
same diameter as that of the wick, according to the form of flame
desired.
Figures 4, 5, and 6, show several modification; Figure 4, as applied
to a flat wick, while Figure 5 shows two flat wicks with provision for a
current of air between them, a perforated cone and cap enclosing the
parts; Figure 6 shows the same construction of cap as applied to a.
tubular wick.
In order to obtain a flame of greater brilliancy I may apply a ring or
cap of platinum above the cap D; or I may make this perforated cone or
tube L of this metal with a similar object; and further, to obtain more
perfect combustion I may make the cap of the form shown in Figure 7
with internal tubes or passages, as shown, in which tubes the air entering
at A becomes superheated before impinging on the.
The same effect may be obtained by a spiral tube such as that shown
in Figure 8.
Also to obtain a more uniform as well as a more abundant feed and a
greater concentration of the gases around the wick, more especially in the
case of heavy oils, I surround the central wick C, Figure 9, with ą
second stationary wick T, contained in a tube 8, descending to the bottom
of the oil holder, through holes U in the bottom of which tube the oil is
supplied to the wicks.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourteenth day of September, in the year of
our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alexander Melville Clark, Her special
licence that I, the said Alexander Melville Clark, my executors, adminis-
trators, and assigns, or such others as I, the said Alexander Melville
Clark, 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," a communication to me from abroad by Emile
Granier, of Paris, France, upon the condition (amongst others) that I,
the said Alexander Melville Clark, 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 Alexander Melville Clark, 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 Sheet of Drawings
hereunto annexed and to the letters and figures marked thereon (that
is to say) :-
This Invention relates to improvements in lamps for burning mineral
vegetable, or animal oils.
The ordinary carcel or moderator lamp which has a straight tubular
burner composed of two concentric tubes of considerable height with
an annular space between them for the passage of the wick, gives no
cast shadow and therefore produces a light radiating in every direction
down to and around the foot of the lamp.
I have endeavoured in the lamp of this Invention to secure the same
advantages by making the burner straight and of the smallest possible
diameter, at the same time providing it with all the improvements

page_text: necessary to ensure the perfect combustion of liquids, which in general
produce a smoky flame and a disagreeable odour, which can with
difficulty be avoided, such for example as petroleum and schist oils.
In the accompanying Drawing Figure 1 is a vertical section of an
arrangement of lamp with which good results have been obtained; A is
a metallic cap to which air is admitted around its base B only. This
cap A is fitted to slide on the wick tube at O in order that it may be
adjusted to increase or diminish the admission of air at B, as well as to
regulate its height in regard to the flame, and also to enable it to be
readily removed for the purpose of trimming the wick and cleaning the
burner.
For some kinds of liquid fuel I may provide the cap with one or more
rows of holes or openings i, for admitting air in a lateral direction
around the wick, and sometimes with one or more rows of holes at point
V, also for increasing the air supply at the base of the cap. ·
In the arrangement, Figure 2, which shows a section of a complete
lamp, I obtain still better results by perforating the whole of the cap as
at D except the top d, by which means a steady colorless flame is pro-
duced without smell and radiating but little heat. This cap which may
be made either of perforated sheet metal or of wire cloth is of less
diameter than when unperforated, as in Figure 1.
In some cases I apply at the top of the inner wick tube which forms
a central air passage, a perforated metal or wire cloth tube L of
cylindrical or conical form, or it may be slightly enlarged or flared
towards the flame, according to the form of flame I desire to produce.
This tube or cone may be made of platinum for the purpose of increasing
the brilliancy of the flame. The use of the interstitial or perforated cap
D enables a pure colorless Hame to be obtained without any smoke from
liquids which otherwise would produce a fuliginous flame, and it has the
further advantage of enabling any kind of glass chimney whether of
cylindrical, conical, or other form, such as that used with the moderator
lamp or a globe only to be used to shelter the flame. It is however
preferable to use a glass chimney E having one or more rows of holes f,
and contracted in diameter from P upwards to the top, or to Q only,
where there may be a second row of holes f,f, above the flame, and the
chimney may be further reduced in diameter from K to M. In this
manner a perfect combustion of the gas is ensured at the same time that

page_text: a more intense flame is obtained without any increase in the con-
sumption of oil. As the interstitial or perforated burner, Figure 2, is
supplied with a sufficient amount of air for combustion by the lateral
openings, the air inlet B, Figure 1, which is indispensable in the former
case may be dispensed with, thereby enabling the cap to be made of
small diameter, and of a form adapted for fixing either to the wick tube
or gallery G. In Figure 2 Y is the body of the lamp; A, outer wick
tube; B, inner wick tube giving passage to an inner current of air
which may be admitted either at B¹ or at the bottom of the lamp by
carrying the tube down low enough; C, wick; D, perforated cap; d,
unperforated part of the same; E, chimney, f, holes in the chimney just
below the shoulder P; ƒ, f, similar holes just below the second shoulder
K; G, chimney gallery; H, rack for adjusting the wick; i, platinum
ring serving to increase the brilliancy of the flame; L, perforated metal
or wire cloth tube straight, conical, or flared to divide the air in the
interior of the flame; M, contracted top of the chimney; X, openings
admitting air around base of cap D; Z, attachment of cap D to wick
tube.
In Figure 3 the chimney is shown as supported either by a wire gauze
or perforated metal casing A, whereby a much larger quantity of air
may be supplied to the flame.
The orifice of the cap may be made either larger, smaller, or of the
same diameter as that of the wick, according to the form of flame desired,
and the cap may be applied to various forms of wick, as shown in Figures
4, 5, and 6; Figure 4 shows it as applied to a flat wick, while Figure 5
shows two flat wicks with provision for a current of air between them, a
perforated cone and cap enclosing the parts; Figure 6 shows the same
construction of cap as applied to a round wick.
In order to obtain a more perfect combustion I may make the cap of
the form shown in Figure 7 with internal tubes or passages, as shown, in
which tubes the air entering at A become superheated before impinging
on the flame.
"
The same effect may be obtained by a spiral tube such as that shown
in Figure 8.
Also to obtain a more uniform as well as a more abundant feed and a

page_text: the case of heavy oils, I surround the central or combustion wick C,
Figure 9, with a second or alimentary wick I, contained in a tube S,
descending to the bottom of the oil holder, through holes U in the
bottom of which tube the oil is supplied to the wicks.
Having described the nature of the Invention, and the manner of
performing the same, I declare that what I claim as the Invention to
be protected by the herein-before in part recited Letters Patent is,-.
1st. The means of obtaining and regulating an air inlet at the base of
an unperforated cap whose diameter is but slightly greater than that of
the wick, and also the providing a lateral inlet for air in the said cap
opposite the base of the flame, substantially as herein shown and
described.
2ndly. The use and application of the perforated or interstitial cap
provided with lateral apertures. below, around, and above the base of the
flame, substantially as herein set forth.
•
3rdly. The construction and use of a chimney with successive con-
tractions and apertures for the admission of the external air near or
above the summit of the flame, substantially as herein described and
illustrated in the Drawings.
4thly. Constructing the caps, tubes, or rings, herein specified as
improvements in lamps, wholly or partially of platinum, as specified.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Eleventh day of March,
in the year of our Lord One thousand eight hundred and
seventy-five.
A. M. OLARK. (L.S:)