IMPROVEMENTS IN THE MUSICAL INSTRUMENT KNOWN AS THE PYROPHONE, TOGETHER WITH THE APPLICATIONS OF THE SAME
Year: 1874

page_text: LETTERS PATENT to Alexander Melville Olark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN THE MUSICAL INSTRUMENT KNOWN AS THE PYROPHONE,
TOGETHER WITH THE APPLICATIONS OF THE SAME."-A communication
from abroad by Georges Eugène Frédéric Kastner, of Paris, France.
Sealed the 30th April 1875, and dated the 11th November 1874.
PROVISIONAL SPECIFICATION left by the said Alexander Melville
Clark at the Office of the Commissioners of Patents, with his
Petition, on the 11th November 1874.
I, ALEXANDER MELVILLE CLARK, of 53, Ohancery Lane, in the County
of Middlesex, Patent Agent, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE MUSICAL INSTRUMENT KNOWN AS THE
PYROPHONE, TOGETHER WITH THE APPLICATIONS OF THE SAME," to be as
follows:-
-
-
This Invention relates to improvements in a musical instrument known
as the pyrophone, in which musical sounds are produced by the vibration
of flames of pure hydrogen gas within glass or other tubes.

page_text: ..
It is well known that if a flame of pure hydrogen gas be introduced
within a glass or other tube, and if it be so placed as to be capable of
vibrating, there is formed around this flame, that is to say, throughout
the whole of its enveloping surface an atmosphere of hydrogen gas,
which in uniting with the oxygen of the air in the tube burns in small ||
portions, each composed of two parts of hydrogen to one of oxygen, the
combustion of this mixture of gases producing a series of slight explo-
sions or detonations. Thus, if the number of these detonations be equal
to the number of vibrations necessary to produce a sound in the tube, all
the acoustic conditions requisite to produce a musical tone are fulfilled.
This sound may be caused to cease either by increasing or reducing the
height of the flame, and consequently increasing or diminishing its
enveloping surface so as to make the number of detonations no longer
correspond with the number of vibrations necessary to produce a musical
sound in the tube; or by placing the flame at such a height in the tube
as to prevent the vibration of the enveloping film in consequence of the
insufficient supply of air.
Another mode, which is that employed in the pyrophone, consists in
the use of a double burner producing two flames, the sum of whose
detonations is equal to the number of vibrations necessary for producing:
a musical sound in the tube. The two branches of the burner are
jointed, so that they may be made to approach or recede from one
another by means of a key and suitable mechanism, as in a piano.
When no sound is to be produced the two branches and consequently
the two flames are brought together or nearly so, whereby there is an
interference of the two flames, and the sound ceases, but.by separating
the flames their vibration will be re-established, and the sound will be
produced in the glass or porcelain tube by which they are enclosed. A
series of tubes each containing two flames, arranged as above described,
and operated by means of a suitable keyboard, constitutes the musical &
instrument known by the name of the pyrophone.
The present Invention relates to improvements in this instrument,
and consists, 1st, in an improved arrangement of the burners whereby
they are adapted for burning ordinary illuminating gas instead of pure
hydrogen gas, as before. There is however this difficulty in employing a
common gas, which it is known is a bicarburet of hydrogen more or less
pure, as the oxygen of the air combines with the carbon contained in
the gas instead of with the hydrogen, and the detonations above men-

page_text: tioned are no longer produced. The greater the flame the more carbon
it contains, but it has been found that if the size of the flame be
diminished the proportion of carbon contained diminishes also, but to a
greater extent. Thus if a given flame contains 10 of carbon, a flame half
the size will contain but 3 or 2, of carbon, and a flame one-fourth the
size ¼ or ¼ of carbon, and so on. Now the first improvement consists
in employing 6, 7, 8, 9, 10, or a greater or less number of branches or
nipples, each furnishing a very small flame, the aggregate number of
the detonations of all these flames being equal to the number of vibrations
of the air contained in the tube requisite to produce a singing sound
therein. The cessation of the sound is caused both by bringing the
whole of the small flames together or by two's and two's, and the sound
is produced on the separation of each of the flames.
The burners may be arranged and constructed in various ways, some
3 examples of which are illustrated in the accompanying Drawing.
Figure 1 shows on an enlarged scale a central vertical section on line
1-2, Figure 2, of a burner composed of a number of branches, which
are disposed around a disc, and capable of being made to approach or
recede from a common centre.
) Figure 2 is a plan of the burner. a, gas inlet pipe surmounted by a
supporting disc 6; c, branch tubes in any suitable number pivoted at d
around disc 6, and each terminating in a small nipple; f, flexible coup-
lings connecting branch pipes c with the supply pipe ate; g, springs
attached to disc b, and serving to make the nipples at which the flames
5 emerge converge towards the centre when no sound is to be produced;
h are cords attached one to each branch c, and passing round a guide
pulley and connected to a sliding collar on pipe a. This collar is
connected by suitable mechanism with one of the keys of a keyboard, so
that on pressing down the key the slider will be drawn down, the
branch tubes oscillated, as shown in dotted lines, and the circle of nipples
expanded, so that the latter being thus isolated from one another the
desired sound will be produced.
Figure 3 shows in perspective a burner composed of two concentrio
rings j, l, with nipples k, m, and Figure 4 shows a plan of same. x, o,
5 gas supply pipes to rings j,l. The rings j, l, are brought to the same
level when the circles of nipples k, m, are to be approached together to
effect the cessation of sound, and brought to different levels, as shown in

page_text: Figure 3, by means of a key and intermediate mechanism, before ex-
plained, when the sound is to be produced.
Instead of having nipples around the rings they may be simply tubes
or a continuous slit in the top side of the rings.
These improved composite burners may be applied to chandeliers,
gaseliers, stage footlights, and in gas lighting apparatus generally, by
substituting the same for the ordinary burners, or they may be used in
combination therewith, whereby both light and sound may be produced.
In the case of gaseliers, which are usually placed in the centre of a
ceiling, the improved acoustic burners may be manipulated from a :
keyboard in an adjoining room having electrical connections with said
burners.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Melville Clark in the Great Seal Patent
Office on the 10th May 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of November, 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,
administrators, and assigns, or such others as I, the said Alexander
Melville Olark, 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 THE MUSICAL INSTRUMENT KNOWN AS THE PYROPHONE,
TOGETHER WITH THE APPLICATIONS OF THE SAME," a communication to me

page_text: from abroad by Georges Eugène Frédéric Kastner, 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 Olark, 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 a musical instrument
known as the pyrophone, in which musical sounds are produced by the
vibration of flames of pure hydrogen gas within glass or other tubes.
It is well known that if a flame of pure hydrogen gas be introduced
within a glass or other tube, and if it be so placed as to be capable of
vibrating, there is formed around this flame, that is to say, upon the
whole of its enveloping surface an atmosphere of hydrogen gas, which in
uniting with the oxygen of the air in the tube burns in small portions,
each composed of two volumes of hydrogen to one of oxygen, the com-
bustion of this mixture of gases producing a series of slight explosions
or detonations. If such a gaseous mixture exploding in small portions
at a time be introduced at a point situate at a distance from the bottom
of the tube equal to about one-third of the whole length of the tube,
and if the number of these detonations be equal to the number of
vibrations necessary to produce a sound in the tube, all the acoustic
conditions requisite to produce a musical tone are fulfilled. This sound
may be caused to cease in several ways, 1st, by either increasing or
reducing the height of the flame and consequently increasing or
diminishing its enveloping surface so as to make the number of deto-
nations no longer correspond with the number of vibrations necessary to
produce a musical sound in the tube; or, 2ndly, by placing the flame at
such a height in the tube as to prevent the vibration of the enveloping
film.

page_text: Thus if a flame of given size contains 10 of carbon; for example, a
flame half the size will not contain 5 but only 3 or 3½, a flame one-
fourth the size or ¼ only of carbon and so on.
I therefore propose.
to employ burners having a number of nipples, each giving a very small
flame containing very little or no carbon, but in order to obtain the
requisite amount of vibrating surface, that is to say, a number of deto-
nations equal to the number of vibrations requisite to produce a musical
tone in the tube I have devised the improved construction of burner
which I will now describe:-The first improvement therefor consists in
employing six, seven, eight, nine, ten, or a greater or less number of
branches or nipples, each furnishing a very small flame, the aggregate
number of the detonations of all these flames being equal to the number
of vibrations of the air contained in the tube requisite to produce a
singing sound therein. I have by this means rendered the use of illu-
minating gas practically available in the pyrophone, and I more par-
ticularly claim this arrangement of burner composed of a number of
small nipples grouped together as described. The cessation of the
sound is caused either by bringing the whole of these small flames
together or by two's and two's only, and the sound is reproduced on the
separation of the flames.
The burners may be arranged and constructed in various ways; for
instance the burner may be composed of a number of separate and equi-
distant branches jointed around a disc terminating in separate nipples
which are moved away from or towards a common centre to produce or
stop the sound as required. Or the burner may be formed of two con-
centric tubular rings both furnished with the same number of nipples,
the one ring being smaller than the other in order that it may be intro-
duced within it, so that when the two rings of nipples are in the same
horizontal plane the flames of the one will be brought close to those of
the other to stop the sound which is reproduced immediately the rings
are separated.
According to another arrangement of burner two rings are employed
like those just described, but having holes or a continuous slit in their

page_text: Figure 1 shows on an enlarged scale a central vertical section on
line 1-2, Figure 2, of a burner composed of a number of branches,
which are disposed around a disc, and capable of being made to approach
or recede from a common centre.
Figure 2 is a plan of the burner. a, gas inlet pipe surmounted by a |
supporting disc b. c, branch tubes, in any suitable number, pivoted at d
by ears received in notches around disc b, and each terminating in a
small nipple. f, flexible coupling connecting branch pipe c with the
supply pipe at e. g, springs attached to disc b, and serving to make the
nipples at which the flames emerge converge towards the centre when
no sound is to be produced. h are cords attached one to each branch c
and passing round a guide pulley i, and connected to a sliding collar r
on pipe a. This collar is connected by suitable mechanism with one of
the keys of a keyboard, so that on pressing down the key the slide r
will be drawn down, the branch tubes oscillated, as shown in dotted lines,
and the circle of nipples expanded, and on the latter being thus separated
from one another the desired sound will be produced.
Instead of actuating the tubes by means of cords h and springs g, as
described, they may be controlled by the arrangement illustrated in
central vertical section in Figure 3, in which 1 is a collar fitted to slide :
upon the upper solid extension of tube a, and rigidly connected to
slider by tie rods 2, 2. The collar 1 has a groove around it at 3 to
receive the extremities of arms 4 on the pipes c. Thus by simply
drawing down the slider the arms 4 will be depressed, and the branch
tubes brought together as indicated, while by sliding said collar upwards:
the reverse action will take place.
I may also dispose within the glass tube a diaphragm, placed a few
inches below the branch pipes, to serve as a damper to prevent the pro-
longation of the sound, more particularly in the large pipes. By opening
and closing this diaphragm or damper more or less the intensity of the
sound may be varied. This device is illustrated in central vertical
section, Figure 3, taken on line 3-4, Figure 4, which is a plan of same;
Figure 5 shows a view taken at right angles to Figure 3. In these
three Figures the damper is shown in the closed position, while in
Figure 6 it is shown open. 5, 5, are two semicircular flaps to form the
damper, each hinged at 6 in plates 7 mounted on tube a. 8, 8, are two

page_text: tappets fixed on rods 2, and operating the damper in the following
manner :-When slider is drawn down to bring the flames together and
stop the sound, as before explained, the tappets 8, 8, are caused to bear
on the tail ends 9, 9, of flaps 5, and raise the latter to the position shown
5 in Figures 3 and 4, thereby stopping the sound in the pipe. On the
reverse movement of the slider the flaps 5 are released, and fall into the
position shown in Figure 6.
Figure 7 shows in perspective a burner composed of two concentric
tubular rings j, l, with nipples k, m, and Figure 8 shows a plan of
) same. 2, 0, gas supply pipes to rings j, l. The rings j, l, are raised one
above the other, as shown in Figure 7, to produce the sound, and are
brought to the same level so as to unite the flames from the two circles
of nipples k, m, and stop the sound, these movements being effected
by means of a finger key and intermediate mechanism, as before
explained.
The Invention also consists in the application of these multiple
burners to chandeliers, gaseliers, stage footlights, and in gas lighting
apparatus generally, so as to constitute a musical instrument or pyro-
phone in the form of a chandelier, gaselier, footlights, or other gas
lighting apparatus. To this end I may either substitute for the ordinary
burners the multiple burners and tubes above described, or the two kinds
may be employed in combination, whereby both illuminating and
musical effects are produced.
In the case of gaseliers, which are usually placed in the centre of
a ceiling, the improved acoustic burners may be manipulated from a
keyboard in an adjoining room having electrical connections with said
burners.
Having described the nature of the Invention and the manner of per-
forming 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 use, as described, of a compound burner consisting of any
number of single burners or nipples emitting small flames, which flames
may be separated or conjoined to produce or stop the sound as desired,
whereby ordinary illuminating gas, or any combustible gas other than
pure hydrogen, may be employed in the musical instrument known as
the pyrophone, all substantially as shown and described.

page_text: 2ndly. The employment of these burners, arranged and applied as
above described, in gaseliers or chandeliers, stage footlights, and other
gas lighting apparatus, as and for the purpose specified.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Tenth day of May, in {
the year of our Lord One thousand eight hundred and seventy-
five.