IMPROVEMENTS IN PIANOFORTES, AND OTHER KEYED MUSICAL INSTRUMENTS
Year: 1876

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields, in the
County of Middlesex, Gentleman, for the Invention of "IMPROVEMENTS IN
PIANOFORTES, AND OTHER KEYED MUSICAL INSTRUMENTS." A communication
from abroad by Edward Zachariae, of Vienna, in the Empire of Austria.
Sealed the 23rd March 1877, and dated the 11th October 1876.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at the
Office of the Commissioners of Patents on the 11th October 1876.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. " IMPROVEMENTS IN PIANOFORTES AND OTHER KEYED MUSICAL IN-
STRUMENTS." A communication from abroad by Edward Zachariae, of Vienna, in
the Empire of Austria.
This Invention relates to resonant devices intended especially for pianofortes, but
which in a modified form are also applicable to other keyed musical instruments, such
for example as harmoniums, and it consists in the use of peculiar sounding cells or
cellular boxes arranged within the instrument, and of devices for bringing these
sounding cells or boxes into contact with the ordinary sound board, in order to
induce their resonant action.
It also consists in the use of similar cellular sounding boxes as stages or platforms
for keyed musical instruments. These sounding cells are preferably of a longitudinal
prismatic form and provided with an aperture or apertures for the passage of the
air. They may be arranged above or below the strings and sound board; or they
may be arranged below the legs of the instrument, and then form a stage or plat-
form for the same.
It is generally preferable to construct the sounding boxes with partitions, so as to
form cells of different length producing different determined tones.
Single cells constructed on the same principle may be fixed in the small free
spaces at the sides of the frame of the piano and between the cross beams beneath
the sound board, thus utilising all the small spaces into which an entire sounding
box could not be arranged.
When these cellular boxes and single cells are arranged within the case of the
musical instrument they are made to communicate or are brought into contact with
the ordinary sound board by means of arrangements which may be called induction
bars or induction wings, and which are so arranged as to touch the sound board
[Price Gdl

page_text: with one end and the resonant cells or boxes with the other end, thus enabling
them to transmit the vibrations of the sound board to the said resonant cells or
boxes.
It is generally preferable to construct these induction arrangements so that they
can yield to pressure, without however being so clastic as to absorb the vibrations
proceeding from the sound board. A suitable construction for attaining this object
consists of two flaps hinged like a pair of wings to a rod or strip of wood, and
connected together by spiral springs.
For the purpose of modulating at will the resonant action of the lower sounding
box or of the sounding platform flaps may be arranged in front of and behind the
lower sounding box, and these flaps may be connected with pedals, thus enabling
the spaces in front of and behind the said sounding box to be more or less opened
or closed, thereby more or less preventing the sounds from passing down out of the
case of the musical instrument.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Henry Johnson in the Great Seal Patent Office on the 7th
April 1877.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN PIANOFORTES AND OTHER KEYED MUSICAL IN-
STRUMENTS." A communication from abroad by Edward Zachariae, of Vienna, in
the Empire of Austria.
The said Invention has for its object improving the sound of pianofortes, har-
moniums, and similar keyed instruments, and consists in arranging sounding cells
or cellular boxes within the instrument, also of devices which may be used for
conveying the vibrations of the ordinary sounding board to such sounding cells, and
further in the use of similar cellular sounding boxes arranged below the instrument.
And in order that the said Invention may be perfectly understood I shall now
proceed more particularly to describe the same, and for that purpose shall refer to
the accompanying Drawings, which illustrate the Invention as applied to a grand
piano, to an upright piano, and to a harmonium; it will be evident however that
the said Invention is applicable to all other forms of pianos, and also to other keyed
musical instruments.
Figure 1 (Sheet 1) of the Drawings represents a plan with the top board assumed
to have been removed of a cellular sounding box constructed according to the said
Invention, and to be arranged in this case above the strings and between the sides
of a grand piano.
Figure 2 represents a transverse section of a piano provided with the cellular
sounding boxes arranged above and below the strings and below the legs of the
instrument; Figure 3 is a section of a portion of the same taken along the line 1-2,
(Figure 2).
Figure 4 is a sectional perspective view drawn to an enlarged scale illustrating
the arrangement which may be used for communicating the vibrations of the
ordinary sounding board in a direct manner to a sounding box, or of one sounding
box to another sounding box.
Figure 5 is a perspective view shewing a multiple cell.
Figures 6 and 7 indicate the manner in which the said Invention may be adapted
to a harmonium.
Figures 8 and 9 are perspective views shewing modified forms of sounding boxes.
Figure 10 is a similar view, showing a sounding box on legs, which may be
placed beneath the instrument, and which extends up to the bottom of the same.
Figure 11 is a perspective view of a piano placed on a large cellular sounding box
forming a platform or stage for the instrument.
Figures 12, 13, and 14, on Sheet 2 of the Drawings, illustrate the manner in

page_text: which the said Invention may be adapted to an upright piano, Figures 12 and 13
being elevations of opposite sides, and Figure 14 a section taken along the lines 3-4,
Figures 12 and 13.
The same letters denote similar parts in all the corresponding Figures.
As shown in Figures 1 and 2 the cellular boxes are divided by longitudinal
partitions g, g, g, and g³, and cross partitions l, into cells a, a, a, a³, each of which
may be provided with one aperture or two opposite apertures, f, f¹, ƒ², ƒ³. By
suitably varying the dimensions of these cells and their apertures, as shown, different
tones may be produced. For transmitting to the cellular boxes the vibrations
proceeding from the sounding board n apparatus may be used which may be
designated "inductors," and which are illustrated by Figures 2, 3, and 4. These
"inductors" are composed of a pair of wings b, or b¹, or 62, attached to small boards
t, or t, or t², by strips u of cloth, leather, or any other suitable flexible material, and
held together by spiral springs v, v, a wedge s being employed for the purpose of
preventing the wings b, 61, 62, from being drawn too closely together. The small
boards t, t, t, are glued to the bottom or top board, as the case may be, of the
sounding boxes in accordance with their positions either above or below the sounding
board n, so that the opened ends of the wings are turned towards the sounding
board.
Figures 2 and 3 show three sets of cellular sounding boxes arranged within the
instrument; one of them (the upper sounding box) is situate above the strings,
another (the lower sounding box) is situate at the bottom of the instrument, and
between both in the free spaces at the sides of the instrument and between the cross
beams there are fixed other smaller sounding boxes, thus utilizing all the spare
room. The wings of the inductors of the upper sounding box may be connected
to the bridge m of the sounding board by means of a strip h fixed to the same, as
shown in Figures 2 and 3; the same Figures illustrate also the manner in which
the inductors b¹ and be may be fixed to the sounding boxes. The free ends of the
wings 6 are in contact with the sounding board n, and the free ends of the wings b₁
are in contact with the bottom boards of the sounding boxes a², a². By this con-
struction the contact between the sounding box and the inductors is made perfect,
and while the wings b, b1, b2, yield to the pressure of the sounding box when the
apparatus is being fitted together their construction is not so elastic as to absorb the
vibrations evolved from the ordinary sounding board n, but they convey such
vibrations to the sounding box. These cells are made of different lengths, so as
to produce different determined tones. Although the use of the inductors is
generally preferred they may be dispensed with if found more convenient to do so.
The sounding box arranged beneath the legs y of the piano may be enclosed in a
case having openings fat the top and sides, as better shown in Figure 11.
Figure 5 shows an arrangement of multiple cell to be placed at some suitable
point within the instrument for resounding the higher and highest notes. It consists
of a number of cells of diminishing size arranged together like the reeds of a pan
flute.
Figures 6 and 7 are respectively a front and an end view showing the manner in
which this Invention may adapted to a harmonium; G, H, J, K, L, are five large
sounding boxes of different heights and the square-shaped cells M which have
different cross-sectional areas are multiple cells like those shown in Figure 5. The
whole may be fastened to a frame N and surrounded or covered by a casing O.
Figures 8 and 9 illustrate modifications in the construction of the sounding boxes,
a portion of the board at the end being represented as broken away, in order to
show the partitions F, F¹. According to these modifications in lieu of each cell
being provided with an aperture made in the top or bottom of the box or in both,
the boards E, E¹, are fixed in such a manner across the longitudinal partitions F, F¹,
as to form cells of different length corresponding to as many different tones.
If desired a sounding box may be arranged on legs so as to stand beneath the
bottom of an instrument, between the legs of the same. A form of sounding

page_text: box suitable for this purpose is shown in Figure 10, the same being mounted on
legs y¹.
Figure 11 illustrates a grand piano constructed according to one modification of
the said Invention, and shows the top sounding box A arranged inside the piano, so
as to leave free spaces C and D in front and behind and a sounding platform B
arranged beneath the legs y of the piano.
Figures 12, 13, and 14, (Sheet 2,) illustrate the manner in which the said Investion
may be applied to an upright piano; Figure 12 shows five multiple cells R, R¹, R², R³, R4,
inserted in the frame P and between the cross beams Q, Q, Q, and Figure 13 shows
three large sounding boxes S, S1, S2, secured inside the frame P¹, which is to be
placed at the back of the instrument, the combination being shewn clearly in the
sectional view, Figure 14.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion, that what I consider to be novel and original,
and therefore claim as the Invention secured to me by the berein-before in part
recited Letters Patent is, the construction of apparatus for improving the sound of
pianofortes, harmoniums, and similar keyed musical instruments, substantially as
herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my Specification
set my hand and seal, the Sixth day of April, One thousand eight hundred
and seventy-seven.
J. HENRY JOHNSON. (L.S.)