CERTAIN IMPROVEMENTS IN PIANOFORTES
Year: 1835

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PIERRE
FREDERICK FISCHER, of Great Marlborough Street, in the County of Middlesex,
Merchant, send greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Thirteenth day of May, in the fifth year of His
reign, did, for Himself, His heirs and successors, give and grant unto me,
the said Pierre Frederick Fischer, His especial licence, full power, sole
privilege and authority, that I, the said Pierre Frederick Fischer, my exors,
admiors, and assigns, or such others as I, the said Pierre Frederick Fischer,
my exors, adors, 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, the Invention of "CERTAIN
IMPROVEMENTS IN PIANOFORTES," communicated to me by a certain Foreigner
residing abroad; in which said Letters Patent, is contained a proviso that I,
the said Pierre Frederick Fischer, shall cause a particular description of the
nature of the said Invention, and in what manner the same is to be performed,
to be inrolled in His said Majesty's High Court of Chancery 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
Pierre Frederick Fischer, do hereby declare that the nature of the said

page_text: The Invention consists of improvements on pianofortes without strings, in
which the sound is produced by different kinds. The same letters indicate tho
same objects in each Figure.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a section. A, key of the key-board; A, A, key pin, avoiding
the friction of the key; B, lever bearing thrce centres, No. 1, 2, and 3, and
at its extremity a hook C, which catches the lever D, bearing the escapement
E, which raises the lower parts of the hammer T, and operates as usually. The
key A has at its extremity a screw with a leather button F, the object of which
is to regulate the height of the key-board. Immediately by the side of it is
another screw button G, which, in raising the lever, makes it revolve on the
centre I, and lowers the opposite side bearing the damper J. This lever H is
screwed on under the moveable piece of wood K. At each extremity of this
piece of wood is a hole, into which an iron pin B, B, enters, marked on the
plan, and having a winding spring, which constantly holds the piece of wood
raised while it lowers the piece of wood by means of the bar U, which communi-
cates with the pedals, produces the forte without causing the lever H to leave
the button. L, a rail of iron, or of any other suitablo material, to which
sounding springs are fixed; one of them, M, described in the plan, enters
with one end into the spring rail L, and is pressed by the pressing screws 0, 0.
At its center is reserved a branch, which receives the stroke of the hammer N;
this branch bears a piece of metal or of wood, which may also be of leather,
as it is explained below. The damper J serves to take away the sound, as in
other pianofortes. To this metal rail L the vertical board O is adapted, which
passes on another board P, formed of four pieces, which unite at the lower end
in one point in the form of a funnel. Q, another vertical board, adapted to
the second iron rail marked on the plan; this rail has also sounding springs.
Figure 2, A, key of the key-board; B, lever bearing the check C, which
strikes under the lower part of the hammer D to make it act; E, check,
keeps it back; F, leather button, which strikes under the hook G to make it
escape; the screw H serves to regulate the escapement; I, copper pin, which
raises the lever damper J; K, a moveable piece to produce the forte.
Figure 3 is a plan representing the key-board as well as the metal rails
L, R, and the manner in which the different plates and springs are fixed.
These springs S, S, S, V, C, C, Y, Z, indicated in the plan, are made of
different forms, and of all sorts of metal, as steel, iron, copper, and brass, silver

page_text: plated, &c., and all mixtures of metals, according to the quality of tone desired
to be obtained, and which a little practice will teach a competent workman.
These springs are partly fixed in the rail by means of holes pierced across and
stopped by a compression screw; the tuning is to be effected by withdrawing
more or less the springs from the rail, and also by the union pieces k, k, fixed
at the other end, which also serve to soften the tone.
The screw I
I have also adapted to this instrument a mechanism to sustain the tone, and
the effect of which is produced by the grooved or fluted cylinder H, H, marked
on the section, and which is put in motion by a rolling cylinder. Figure 4 is
an explanation of the mechanism. A, key of the key-board; B, button which
raises the lever C, on which the button D is fixed, bearing the escapement E,
which, in removing the hammer, strikes the leather button F on the piece of
wood G, which lets it pass, and the check H keeps it back.
passes through the lower part of the hammer J, and rises the damper lever K.
The screw L has a winding spring, which serves to damp the tone. The hinge
piece serves to produce the forte. Figure 5, the lever A, fixed on the
key B, has a stem, on which the escapement C is placed, which in rising
removes the hammer and strikes against the screw D. This mechanism is of
double check: one E placed at the escapement keeps the hammer back when on
the point of passing through; the other F is placed at the stem, and touches
the damping lever G, which in its turn touches the button. H is screwed into
the lower part of the hammer I, and keeps it back from the strings.
Figure 6, A, key of the key-board; B, stem fixed at its extremities in a
lever C to raise the escapement D; the cheek O is placed in the lever C to
keep the hammer back. The damping lever G is raised by the screw F, which
is screwed into the lower part of the hammer E. R, hinge piece which
produces the forte. I, another kind of dampers placed underneath the strings.
Figure 7 shows the mechanism equally applicable to grand horizontal
pianofortes. A, key of the key-board; B, lever, which has a stem C, at the
extremity of which a friction roller D is fixed; this stem raises the escape-
ment E, which in its turn makes the hammer strike; the stem C, in making
an opposite movement to that of the lever E, falls in a notch, which makes
the escapement act, and by the counteraction the check G is brought on the
lower part of the hammer H; I, lever of dampers.
Figure 8, I, lever in which the stem J is fixed and pressed by the screw K;
this stem bears the escapement L, and, in raising it by the button M placed on
the key, makes the hammer fall, and by the screw O, which touches the piece
P, makes it act; the check Q turns them, and keeps the hammer back.
Figure 9, A, lever; B, escapement; C, stem, fixed by the screw D, and

page_text: supporting the check E; a second check F, fixed to the escapement, makes
an opposite movement to the other to stop the hammer; the same instant
when the latter strikes the string, the damper lever II is raised by the
escapement A.
Figure 10, A, key of the key-board; B, lever; D, D, screw to regulate the
escapement C; O, screw, which serves to let it escape; I, check, which keeps
it back; G, winding spring, which raises the hammer; H, screw fixed in the
lower part of the hammer I to regulate it; V, screw fixed on the key, which
has a leather button M, which serves to raise the two levers L, K, to make
the dampers act, which are placed underneath the strings; N, other dampers
placed under the bar of the hammer P, which is put in motion by the pin G.
Figure 11, section of the mechanism striking from behind. A, key of
the key board; B, balance; C, screw stem, which serves to regulate the
escapement by the stem D, which strikes under the lever E which bears
the escapement F, which strikes under the joint of the hammer G to
make it act as it is already explained; H, winding spring which serves to
raise the hammer R; I, a screw with a button to act on the escape-
ment; J, hammer check; K, screw stem, likewise placed in the key of the
key-board, raising the lever L, which bears the stem M passing through
the rail N, and touching at its end the damper which stops the vibra-
tion of the string O; P, hinge piece, which serves to produce the forte; Q,
framing and stays of the-instrument. In this construction the case is stronger
than that of other pianofortes, which are broken through by the key-board; and
the mechanism, Figures 12 and 13, indicating the means to make the touch of
the key-boards light or hard. To produce this alteration of the key-board, the
button A is raised, which raises the part B on its centre C, and by which the
button of the spring D rests on the key, which was placed behind its centre F,
renders it harder to the touch; in lowering the button A by the spring E before
the balance the contrary effect is produced. Several other means can be made
use of to obtain the same object, and in this case, instead of springs, weights
may be employed, as Figure II describes it. The same result can also be
obtained in strengthening the springs employed in the mechanism of the
pianoforte by various proceedings. The different new mechanisms indicated
by the Figures 4, 8, and 9, have the advantage to produce by themselves the
effect of making the touch either hard or light, which takes place in pushing
back or drawing out the key-board, which is moveable, namely, in approaching
more or less to the centre of the lever. The button placed on the key-board
becomes, for the same reason, easier the further it is removed; it makes a
rotation from right to left; and when the key-board makes the damper lever

page_text: rise, the whole bone stem I, I, advances on the grooved cylinder, which gives
it a continued motion, and sustains the tone as long as the key is kept down.
The 兽 cylinder is lifted by means of a pedal, which is moved by the
foot. The instrument, as it is drawn, represents a pianoforte with two strings,
but in order to encrease the power of tone I put in it double springs facing
one another. This instrument transposes at pleasure several keys higher or
lower. The different new mechanisms, indicated on the Drawing No. 2, may
be indifferently employed for these instruments as well as for the pianofortes
described by Figures 2 and 3, in which the tone is produced partly by springs
and partly by strings.
Explanation of these Figures and of their various mechanisms :---Drawing
No. 2, Figure 1, circular or hexagon pianofortes. A, half sphere of copper,
similar to a kettle drum, on which board B is placed by a border of parchment
introduced between the two thicknesses of the board. This parchment board
is drawn up and tightened by the screw C on the half sphere in like manner
as a kettle drum; the whole is fixed underneath the case by iron screws.
D, rail of cast iron, to which the strings F are fixed. On this very rail rests
the frame of the key-board E, which is moveable, and re-enters into the case
whenever the pianoforte is to be shut. Explanation of the mechanism :-F,
the key of the key-board; G, the escapement, the height of which is kept and
regulated by the lever H, and which is removed by the screw I; K, the
spring to remove the escapement; L, check which keeps the hammer back;
M, winding spring to raise it again; N, screw to regulate the spring; 0,
damper; P, pedal for fortes.
Figure 2 is a plan shewing the strings F fixed to the rail D; G, pins ;
II, bridge crossed by bars, sounding spring put on an iron rail communicating
with the sounding board; its destination is to replace the bass strings, which
in this part are too short to have the necessary vibration.
I make
Figure 3 represents the plan of a vertical pianoforte, which is very low, and
which, nevertheless, descends to the lowest bass note. This advantage is obtained
by the use of springs instead of strings in the lower bass octaves.
also pianofortes of this kind with nothing but strings; but then in order to
encrease the length of the bass strings, and to take advantage of the whole
extent of the sounding board, I place them diagonally in this part, they then
pass under the other strings and behind the sounding board, as it will be seen on
the Drawing. A, rail of the points; B, rail of pins to which the strings D
are fixed; G, bridge; E, new bars placed on the board instead of being
underneath as it has been done hitherto; F, sounding spring replacing the bass

page_text: strings. Note, the bars or boards, which hitherto have always been placed, in
the inside of pianofortes, under the sounding board, are in these placed above; on
this account they oppose a far greater resistence and cannot give way, for the
more the bridge is burdened the less the bars are subject to yield. Frequent
efforts have been made to replace the leather used for covering the hammers
by various stuffs, but the common fabrication of these stuffs render them almost
unfit for this use, because these stuffs are of an even or equal thickness, whilst
a gradual declivity is requisite. I believe I have attained the object, and at
the same time added to the equality and quality of the tone, by felt composed
of my Invention, which consists in felting on a stuff of very fine wool, and of
giving it, by felting, the gradual thickness necessary for this use. All my
pianofortes are supported by elastic steam rollers of my Invention, the object
of which is to maintain a constant straightness of the instrument, see the
Drawing, Fig. 14.
In witness whereof, I, the said Pierre Frederick Fischer, have here-
unto set my hand and seal, this Thirteenth day of November, in the
year of our Lord One thousand eight hundred and thirty-five.
PIERRE FREDERICK (L.S.) FISCHER.
PIERRE FREDERICK (L.S.) FISCHER.
AND BE IT REMEMBERED, that on the Thirteenth day of November, in
the year of our Lord 1835, the aforesaid Pierre Frederick Fischer came before
our said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Inrolled the Thirteenth day of November, in the year of our Lord One