IMPROVEMENTS IN SPIRIT LAMPS
Year: 1845

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY ROBERTS, of Norfolk Villa, Finchley Road, Saint John's Wood, in the
County of Middlesex, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-ninth day of July, in the ninth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
John Henry Roberts; my exors, aduiors, and assigns, Her especial licence,
full power, sole privilege and authority, that I, the said John Henry Roberts,
my exors, admiors, and assigns, or such others as I, the said John Henry
Roberts, my exors, adññors, or assigns, should at any time agree with, and no
others, from time to time and at all times during the term of years therein
expressed, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, my Invention of
IMPROVEMENTS IN SPIRIT LAMPS;" in which said Letters Patent is contained
a proviso that I, the said John Henry Roberts, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, to be inrolled in Her said Majesty's High Court of Chan-
cery within six calendar months next and immediately after the date of the
said in part recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Henry Roberts, do hereby declare that the nature of my said Invention.

page_text: and the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, reference being
had to the Drawings hereunto annexed, and to the figures and letters marked
thereon, that is to say :-
My Invention consists,-
First, of the combination of three particulars of mechanical construction in
the same lamp.
And secondly, my Invention consists of the combination of two particulars
of mechanical construction in the same lamp.
And in order that my Invention may be most fully understood and readily
carried into effect, I will proceed to describe the means pursued by me.
The first part of my Invention relates to a peculiar combination of three
particulars of construction in the same lamp for burning spirit. First, that
the lamp shall be an Argand lamp, with an internal current of air deflected
by a button against the interior of the flame; second, that the lamp shall have
currents of air interior of a cone or deflecting instrument, so arranged as to
deflect the air (rising up within it) against the exterior of the flame below
the button, or at a point intermediate of the button, and slightly below the
top of the wick tube; and thirdly, that the lamp shall be so arranged that
there shall be currents of air introduced into the interior of the chimney and
exterior of the cone or deflecting instrument. And I would wish at the
outset to state, in respect to this part of my Invention, that I make no claim
to either or any two of the above particulars of arrangement; this part of my
Invention having for its object the combination of the three particulars as
herein described, so as to obtain a greatly improved lamp for burning spirit.
And in order that the manner of carrying this part of my Invention into
effect may be fully understood by a workman, I will proceed to describe the
Drawings, in the various Figures of which the same letters are used to indicate
the same parts.
DESCRIPTION OF THE DRAWINGS.
Figure 1 represents a section of the upper part of a table lamp made
according to the first part of my Invention, the whole of the parts being
shewn; Figure 2 shews another section; and Figure 3 a plan of the lamp,
the gallery chimney, the upper part of the outer wick tube, and the wick
holder being removed. The other Figures shew various of the parts separately.
a is the glass or other suitable vessel for holding the spirit to be burned; b is
the internal tube by which the internal current of air is obtained to the flame;
c is the button placed on the stem c¹, such stem being supported on the bar c

page_text: fixed in the upper part of the tube b; and thus the internal current of air
coming up the tube b is deflected against the interior of the flame; and at a
point above that at which the air is deflected against the exterior of the flame,
by the cone or instrument used to deflect the air to or against the exterior of
the flame; d is the cone, which I prefer to use for deflecting the air against
the exterior of the flame; and I prefer it to be so arranged as to deflect the
air at a point between the top of the wick tube e, and the button c; and for
the lamp shewn, the position of the upper part of the deflector in respect of
the button (with chimney as drawn) is the best for obtaining the fullest result;
but, in order that the lamp may in this respect be capable of adjustment to
meet any slight difference of construction or circumstances, I have shewn the
parts made with screws, so as slightly to vary the relation of the parts from
those shown. f is the gallery, which is so constructed that currents of air
may enter within and pass up through the deflector or cone d; and the air
passing into the cone or deflector will be deflected against the flame at a
point below the button, which is important in this arrangement or combina-
tion of parts; and the gallery is also so constructed that currents of air will
pass up between the chimney and the outer part or surface of the cone, as
indicated by arrows; and after many experiments I have found that these two
currents, and the interior current in the tube b, should be adjusted in respect
to each other, in order to obtain the fullest effect; and that any considerable
alteration from what the Drawing shows, either of increase or decrease, in
respect to the three separate currents of air (on which this lamp depends),
materially injures the beneficial results obtained by the arrangement or com-
bination of the three particulars of mechanical construction herein pointed
out; and for this reason I would call attention to the relation which exists
between the size of the tube b and the two separate circles of holes in the
gallery of the lamp, because they shew as nearly as may be the exact repre-
sentation of a lamp which burns with the fullest effect; the circle of holes
f having thirty-two holes drilled with a drill of one tenth of an inch in
diameter, the circle of holes f having thirty-two holes drilled with a drill of
one twelfth of, an inch diameter. And I am thus particular in giving these
details, because I have found by experiment that much of the beneficial effect
of the combination herein described depends on the relation the three sources
of air have to each other, the air from each such source acting to produce its
particular end; and these three sources are: first, the air passing through the
tube b; second, the air passing through the holes f¹ into the cone or deflector ;
and third, the air passing through the holes f² into the chimney. And as I
am not able to give an exact rule for calculating such currents of air when

page_text: the diameters of the burners are varied, I have in the Drawings shewn a lamp
of a smaller size, which has a burner of as small a size as I believe will
generally be required for spirit lamps; Figure 4 being a section of the lamp
complete; Figure 5 a section with the button, the upper part of the wick
tube, the wick holder, and the gallery and parts connected therewith removed;
and Figure 6 is a plan of the same. The other Figures shew several of the
parts separately. This lamp is constructed according to the first part of my
Invention, and therefore the description above given will apply to this lamp,
the same letters of reference being used to the corresponding parts; but as
the interior tube b is less in diameter, so also are the circles of holes f¹, ƒ³,
capable of supplying less air; and the Drawing shows the circle of holes f
to contain twenty-four holes drilled with a drill of one tenth of an inch in
diameter, the circle of holes f" having twenty-four holes of one fourteenth of
an inch diameter. I have shewn the height of glass chimneys which I prefer;
and it should be stated that a higher chimney requires more air admitted at
ff, and a shorter chimney requires less air; and it is important that the air
at f¹, f, should be admitted through small holes in place of through long slits.
From these two lamps, which are of sizes which will be those commonly and
generally required, a workman will readily make lamps of other diameters of
burners according to this part of my Invention, if desired. Although I have
been particular in shewing how the two sources of air f¹, f, are obtained
through the gallery, I do not confine myself to the exact details, so long as the
requisite two sets of currents of air for the exterior of the flame be obtained.
I will now describe the second part of my Invention, a lamp made accord-
ing to which is shewn by the Drawings; Figure 7 being a section of the lamp
complete, and Figure 8 shews some of the parts separately, and all of the
parts are marked with the same letters of reference as those before used; and
therefore, in describing this second part of my Invention, it will only be
necessary to call attention to the two 'particulars of construction, on the com-
bination of which in the same lamp the novelty of this part of my Invention
depends. This lamp has only two sources of supply for air to the burner.
First, through the tube b, and secondly, through the holes f¹ into the cone or
deflector. And this part of the Invention consists in confining the quantity of
air passing through f¹ to such a quantity of air as will produce the fullest
effect when combined with an internal supply of air at 6; and I would at
once state that lamps for burning spirit have before been made wherein only
two sources for the supply of air (one deflected on to the interior and the
other deflected on to the exterior of the flame) were employed; and therefore
I do not claim that mechanical arrangement and combination generally; and

page_text: it is only when the dimensions of the source for the passage of air to be
deflected against the exterior of the flame are reduced, as herein mentioned,
(so as to introduce only so much air at a point below the button and above
the wick tube as will produce the peculiarly beneficial effects obtained in
lamps made according to this part of my Invention) that I make any claim
to invention. After many experiments I have discovered that the quantity of
air heretofore admitted under the cone or deflector, in cases when the same
has been deflected at a point between the button and the wick tubes) has
been far too great; and I have discovered that with the size of the tube b
shown, that an admission of air into the cone equal to that of fifty-six holes,
each of the tenth of an inch diameter, produces a change of flame like the
lamps herein-before described, and a very advantageous result is obtained over
all other spirit lamps, excepting that first above explained. And I have
further, by experiment, discovered, that if the quantity of air at f' be greatly
increased or greatly decreased from the quantity above given, the effect is
materially reduced, and the maximum of air which can with any practical
advantage be allowed to pass to the exterior of the flame (produced by the
size of burner tube shewn) is that which would pass through seventy-eight
holes of the size above mentioned, and it requires great care to obtain a
changed flame in a spirit lamp with the size of burner tube shown, when so
large an extent of opening (as seventy-eight holes, each of the one tenth of
an inch diameter,) is used; and therefore I confine this part of my Invention
to such a restriction of the supply of air to the interior of the cone (in
respect to the interior supply of air at b), that it shall not be greater than the
area of seventy-eight holes of the size above mentioned is to the interior of
the tube 6 which is shown, and that such air shall be deflected on to the flame
at a point intermediate of the button and the top of the wick tube; and
although the size of the holes may be varied, yet it is necessary that the air
should be admitted through numerous small holes in place of through long
slits; and it should be stated that I have found that, if the quantity of air
be considerably increased above the fifty-six holes above mentioned, then the
length of the chimney shewn will require to be decreased. It will be desirable
to state that the wicks I use are woven with a weft of silk similar to what
have heretofore been used in France and also in England; and I purchase
them of Mr. Moore, of No. 4, St. James Street, Clerkenwell.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that I make no claim to the
separate parts shewn and described, nor do I confine myself to the shapes of
the various parts; but what I claim is,―

page_text: First, the combining the three particulars of mechanical construction in
the same lamp suitable for burning spirit, as above described; and,
Secondly, I claim the combining the two. particulars of mechanical con-
struction in the same lamp suitable for burning spirit, as herein described.
In witness whereof, I, the said John Henry Roberts, have hereunto set
my hand and seal, this Twenty-ninth day of January, in the year of
our Lord One thousand eight hundred and forty-six.
JOHN HENRY (L.s.) ROBERTS.