CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF PIANOFORTES
Year: 1841

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
STEWARD, of Wolverhampton, in the County of Stafford, Esquire, send
greeting.
WHEREAS Her present most Excellent Majesty, Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Seventh day of July, in the fifth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said John
Steward, Her especial licence, full power, sole privilege and authority, that
I, the said John Steward, my exors, admors and assigns, or such others as I,
the said John Steward, my exors, admors, 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 "CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF PIANOFORTES;"
in which said Letters Patent there is contained a proviso that I, the said John
Steward, shall cause a particular description of the nature of my said In-
vention, and in what manner the same is to be performed, to be inrolled in
Her 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
John Steward, do hereby declare the nature of my said Invention, and the
manner in which the same is to be performed, are fully described and ascer-

page_text: tained 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)-
These Improvements consist-
First, in applying a complete metal framing to bear the strain of the strings
of piano fortes.
Secondly, of a mode of constructing and of applying sound boards of piano
fortes.
Thirdly, of Improvements in applying the bridges of piano fortes.
Fourthly, of a mode of stringing piano fortes.
And fifthly, of a mode of applying the action to upright piano fortes, by
causing the action to proceed downwards from the keys when the strings are
suitably arranged for that purpose.
The frame of the instrument, as shown in the Drawings, is made partly of
cast iron, and partly of wrought iron, or other suitable metal might be used,
but I believe iron to be cheapest and best. The frame is divided into compart-
ments, for the reception of the sound boards, there being in the instrument
shown three sound boards in the same piano forte; but this may be varied;
and the sound boards are connected with the frame of the instrument only
at intervals.
DESCRIPTION OF THE UPRIGHT FRAME AS SHEWN IN THE DRAWINGS A.
(1), the left or bass side supporter, of cast iron; (2), the right or treble side
supporter, of cast iron; (3), the transverse top supporter; (4), the transverse
bottom supporter; (5), the partition supporters; (6), the stud bar; (7), the
screw bar (8), the tension bar; (9), the handles; (10), the partition bar
brackets (11), the square openings for the blocks by which the sound boards
are connected with the frame; (12), the screws for the screw blocks; (13),
the nuts of the upper transverse supporter; (14), the nuts of the bottom
tranverse supporter; (15); the nuts of the screw bar; (16), the nuts of the
stud bar; (17), the shoulder of the stud bar; (18), the studs of the stud bar;
(19), the pins of the stud bar; (20), the screw holes of the screw bar; (21),
the brackets to support the action frame; (22), the partitions for the sound
boards; (23), the stud bar screw of the transverse top supporter; (24), the
stud bar screw of the partition supporter. The left or bass side supporter (1)
of the frame is six feet high (which may be varied according to the length
of string required), and is formed of two iron rails connected together from
front to back, each rail being one inch thick and one inch and a half wide,
and branching out at the bottom, forming two scroll feet, fitted with castors.

page_text: The right or treble side supporter (2) corresponds with the left, except that
it differs in height, being only three feet eight inches. On the outside of these
supporters are placed the handles (9). The transverse supporters (3) and
(4) are two in number; one at the upper part of the frame, and a similar one
at the bottom, each being formed of two rails connected together. Each
supporter is four inches wide and one inch thick. These supporters are
firmly fixed into the bass and treble side frames or supporters (1), (2), by
means of tenons with screws thereon, passing through the side frames (1), (2),
and are affixed by screw nuts. In the top supporter are three square
openings (11), three inches in diameter, for the reception of the blocks of
the sounding boards, to be described hereafter. In the rail at the back part
of these openings the screws for securing the blocks of the sounding boards
are applied. The lower transverse supporter (4), situated at the bottom of the
frame, corresponds exactly with the upper one, with the exception of having.
six openings for the reception of the lower blocks and screws of the sound
boards. The partition supporters (5) are placed between the two side sup-
porters, corresponding with the transverse supporters in width and strength of
iron. These supporters are fixed into the upper and lower transverse sup-
porters by tenons firmly rivetted. At the edge of each front rail is a bracket
(10) for the support of the tension bar. These partition supporters divide
the frame into three compartments (22) for the sounding boards. The stud
bar (6) extends obliquely from the top of the left or bass side supporter (1), to
be attached to the right or treble side supporter (2), fifteen inches from the
bottom of the lower transverse supporter, both ends of which are fixed by a
strong tenon, one inch by one inch and a half, with a screw and a nut on the
other side. This bar is three inches and a half wide, and one inch and a
half thick. The front surface of this bar is bevilled; and on the upper edge
are placed the studs (18) for the attachment of the wires or strings, and on.
the lower edge are fixed the small pins (19). Where the stud bar crosses the
upper transverse supporter it is made firm by means of a screw (23); it is
likewise attached at the front edge of the right partition supporter (24), and
derives additional strength from the brackets (17), half an inch wide, resting
on the upper transverse supporter.
SECTION OF THE SCREW BAR AND TENSION BAR AS SHEWN IN FIGURE 1.
a, screw bar; b, screws of the screw bar; c, nuts of the screws; d, hooks,
for the attachment of loops; e, loop wires; f, loop hook for the attachment of
the string; g, the tension bar; h, polished surface of tension bar; i i represents
one of the tenons of the tension bar; j, groove into which the screw bar is

page_text: placed; represents the tenon at the end of the screw bar, fixed at each of
thefends by their passing into the sile supporters (1) and (2) of the frame:;
l, square holes for the screws to move in.. The. screw bar is:fixed immediately
before the tension bar, in an oblique manner, with the lower back angle
resting in a groove in the tension bar, and secured at each end. by 'tenons that
pass through the side supporters of the frame (1) and (2), fixed by the screw
nuts! The screw bar is three inches and a half deep, one inch and a half
wide, and four feet long, and is perforated with one hundred and seventy
square holes; forming seven octaves. Each hole is a quarter of an inch in
diameter, passing direct through the bar, and are arranged in two rows, an
upper and a lower row, and each hole is a quarter of an inch from the other.
The holes are for the reception of the screws: I resort to one of three modes
of making this bar. First, by using a solid piece of iron, drilled through the
substance. The holes, at first being round, are made a quarter of an inch
square. Or procure three pieces of wrought iron, all of equal length and
depth, as before; but different in thickness, two pieces being a quarter of an inch
thick for the outside pieces, and the other or middle portion-one. inch-thick.
These bars are made perfectly smooth by planing or otherwise. The middle
bar is then marked out on each side, and grooved out at equal distances, each
groove describing three sides of a square. The two outside pieces of iron are
then fixed by means of screws, which will complete this bar, with the requisite
square. holes therein. Or I use two pieces of iron of the size of the two
outside pieces just described, marked out in spaces a quarter of an inch from
each other. On those marks are screwed brass or tin grooves, three and a half
inches deep, corresponding with the depth of the bar. These grooves are
stamped out of tin plates or formed in brass, and are all inade of the same
size, so that when screwed on 'the bars at equal distances they represent
square holes a quarter of an inch in diameter. The other outside bar is
arranged in the same manner, each having eighty-five brass or tin grooves,
and when both are fastened together by means of a piece of iron at either end,
forming tenons to be fastened on the side supporters, as is shown at Figure 2,
the two bars are joined together, a as is shewn at Figure 3. The tin or brass
grooves range alternately so that they do not come opposite each other,
leaving a space between the two bars. This space is filled up with melted tin
or other suitable metal, but tin appears best for the purpose, which firmly
adheres to the sides of the bars and to the tin or brass grooves, the metal
being suitably prepared, as is well understood, for causing the tin to adhere.
Before the melted tin is poured into the intermediate space, the tin or
brass. grooves s should be fitted with square pieces of wood, to prevent the

page_text: .
SECTION OF THE TENSION. BAR AS, SHEWN IN FIGURE 4.
m, groove in which the screw bar is fixed; 'n, polished surface, describing
the segment of a circle, where the loops pass round and move in drawing
the wires 'up to pitch; (o) upper portion of the bar. ". The tension bar is placed
at the bottom part of the frame in front, extending from side to side, and' is
firmly fixed at the two ends by.tenons. This bar is three inches deep, one
inch wide at the top part, gradually becoming thicker at the lower part, where
it encreases to one inch and a half. The lower part describes the segment of a
circle, which is polished for the purpose of facilitating the notion of the loop's
on that surface when drawing up the strings. The screws of the screw bar. are
one hundred and seventy in number (seven octaves); and are placed in the
holes of the screw bar, each screw serving for a single wire. or string:
They are three inches and three quarters long, and three sixteenths of an inch
in diameter, the worm of the screw continuing nearly all its length, the lower
end being made square to prevent each screw from turning in its movements
up its hole in the screw bar. On the screw is fixed a nut, on which 'nut the
tuning key is applied, to draw up the wires for the purpose of tuning. The
partitions marked (22) are for the reception of the sound.. boards, which, as
before stated, are three in number. The first or treble compartiment is sixteen
inches wide, the second or tenor compartment' is seventeen inches wide, and
the third or bass compartiment is eighteen inches wide.
square
I will now describe the construction of sound' boards. The sound boards of
each instrument are three in number (or may be arranged in one or more,
provided the same principle of construction be retained, but the number just
described appear to be the best suited). The sound boards together consist of
twenty-one bars and forty-two sound posts or supporters, peculiarly, con-
structed, and arranged in the order which I will now describe. The sound
boards I denominate as follows:-First, the treble sound board, adapted to the
smallest partition of the iron franie; second, the tenor sound board, occupying
the middle compartment of the iron frame, a size larger than the former; and,
thirdly, the bass sound board, being considerably larger than either of the
others, and fitted in the largest compartment of the said frame. The treble
sound board is constructed in the following manner :-A Swiss deal board,
previously glued down the middle; is planed smooth and finely sand-papered
to the thickness of three sixteenth of an inch all over,i. three feet :long; and
fifteen inches and a half' wide, on the: internal surface of which seven bars, a.

page_text: are placed at equal distances from each other, the first or upper bar being
seven inches long, three eighths of an inch wide, and five eighths of an inch
deep, on the centre of the said bar, gradually becoming thinner as it approaches
the termination on either side, forming a swell in the middle, with a ridge, as is
shewn in Figure 2. The last bar of the said sound board is nine inches long,
half an inch wide, and six eighths of an inch deep in the centre, and is
modelled precisely as the former bar, progressively increasing from the first to
the last. The whole of the bars are sprung on the sound board three eighths
of an inch at either extremity, and are firmly fixed by means of glue and
pressure, producing a rotundity on the outer surface of the said board some-
thing like the belly of a violoncello. Between cach of the bars the wood of
the sound board is thinned to one half its thickness, or rather scooped out,
having the thinnest part midway between each bar, which degree of thickness
is also carried round the extreme points of the said bars a, so that each bar,
by these means, forms a distinct centre of sympathy. The scooping or hol-
lowing out requires to be done in a regular manner, gradually becoming
thicker from the centre between each bar up to the part of the sound board
on which the said bars a are placed. A wood frame, a¹, fitted to the treble
compartment of the iron frame, is now made, with two side parts, a top and a
bottom, with a block a fixed above in the centre of the top rail, and two
others as on the bottom of the frame, which blocks are fixed by means of screws
passing through the back of the iron frame, and they are thus kept perfectly
immoveable, and at the same time the frame of the sound board is of a size
to prevent the sides thereof coming into contact with the partition bars of iron.
The wood frame is made of white deal or pine, one inch and a half thick, and
four inches in depth from the front edge to the back, and veneered on the out-
side with fancy wood. The front edge of the frame is thinned to a quarter of
an inch, for the purpose of fixing the sound board thereon with glue; and on
the sides of the said frame are placed two sound holes, near to the sound
board, for the transniission of the sound arising from the sound board. On
the back edges of the said frame is fixed the back by means of glue, which is
made of hair wood, or any other wood suitable to the purpose, a quarter of an
inch thick all over its surface, and perforated with sound holes for the depar-
ture of the sound. To the extreme end of each bar a, before described as
fixed with glue, a round sound post or supporter y, three quarters of an inch
long, and three sixteenth of an inch in diameter, in a small countersink, one
sixteenth of an inch deep, thus forming two lines of sound posts, seven above
and seven below, which require to be made with great care, and of the finest-
grained white deal, well smoothed with sand paper. The opposite ends of the

page_text: said posts are fixed into a rail z, of white deal, two inches deep, and one inch
thick, which passes, obliquely across in the line of the termination of bars
before described, extending from one side of the wood frame to the other, into
which it is dovetailed and secured by glue. The tenor and bass sound boards,
and their respective bars, are constructed precisely in the same manner as the
above, but proportionately and regularly encreasing in size in the following
order-The sound board of the tenor is one twenty-fourth of an inch thicker
than the treble. The sound board of the bass is one twenty-fourth of an inch
thicker than the tenor. The first sound bar a of the tenor is nine inches
and a half long, three eighths wide, and three quarters deep. The last sound
bar of the tenor is eleven inches and a half long, three eighths and one twenty-
fourth wide, and seven eighths deep. The first sound bar of the bass, is twelve
inches long, three eighths and one sixteenth wide, and seven eighths and one
sixteenth deep; and the last sound bar of the bass is fourteen inches long, half
an inch wide, and one inch deep. The whole of these bars, from first to the
last, may be varied from two to three inches longer than the above description,
keeping in view the appropriate and respective proportions, as before described.
The sound posts of all the sound boards, from the treble to the bass, vary from
three quarters of an inch long to one inch, and from a quarter of an inch to
three eighths in diameter, the strongest and longest being fixed to the bass
sound board. At the upper part of each sound board are formed two sound
holes for the exit of sound, to answer the same purpose as those described in
the backs and sides of the wood frame. I would remark, that in place of the
posts y on the ends of the bars a being affixed to rails, I sometimes affix
them to the centres of a series of similar bars x, which are about half the
lengths of those affixed to the sound bards, such second series of bars being
affixed to two short sounding boards, about an inch longer than the second
series of bars a, and then I apply posts or supports y to each under the
secondary sound boards, opposite each. end of the second series of bars x, which
posts or supports are affixed to rails y, and in such manner that there will be
four rows of posts or supports, and consequently four rails y. By this arrange-
ment it will be understood that the bars x, which are affixed to the sound
board, will be each supported by two further bars a and four posts. And I
would remark, that whatever be the number of sound boards used in the same
instrument, the mode of using sound bars a with posts or supports at their
ends, is to be observed, the size and strength of the bars and posts or supports
encreasing from the treble to the bass, as above explained; and the sound
board or boards are to be affixed to a frame, and such frame securely fixed at
intervals in the metal frame of the instrument; and although I have stated

page_text: there to be twenty-one bars a used in a complete sounding board for a piano-
forte, I do not confine myself to that number, provided the manner of. their
use with posts at their ends be retained.
な
I will now describe the mode of applying the bridge, which is made of
beech, four feet long, half an inch wide at the beginning of the treble part,
gradually widening to the bass extremity, where it is three quarters of an
inch, and one inch deep. The bridge is arched out, so as to form twenty-one
butments, each butment resting on the 'sound board, the said butment cor-
responding with the thickness of the middle of the bar which is placed inime
diately underneath. On the top of the bridge, which is perfectly straight, are
placed the pins to form the lower frets of the wires or strings, as heretofore
practised. I sometimes make the bridge of several parts, each part in length
equal, to include two or three abutments, which come nearly close together,
but their ends do not touch; but the lengths may be varied. . :
The mode of stringing consists in hanging the wires on small studs fixed
on the upper edge of the stud bar, from whence the wires are carried to the
pins at the lower edge of the said bar, forming the upper frets of the strings';
they then pass downwards to the bridge, on which they rest in the usual
manner, forming angles between the respective pins placed therein; and after
passing below the bridge they are hooked upon the loops, constructed in the
following manner:-The loops are ten inches in length, and formed of No. 22
steel wire twisted double, with an eye at one end and a hook at the other,
the former being attached to a screw of the screw bar, as before described,
and after passing on the surface of the tension bar, the other end has a strong
steel or wrought-iron wire hook, to which a string is attached. The tuning
key is then placed on the nut of the screw, as before described, and the wire
is thus gradually drawn up, the tuning key being applied underneath the
mechanism of the action, instead of above, according to the usual custom 'of
tuning.
I will now describe the nature of the action, which differs from that usually
employed in upright pianofortes, by being placed" underneath the keys, the
hammers striking the wires or strings in two distinct lines, as is indicated by
red dots on the strings; the first or treble line describing a segment of a circle,
and the second or bass line passes in an oblique direction. The first or treble
line of hammers begins at the highest treble wires or strings, and "proceeds
gradually upwards underneath the lower edge of the stud bar to the centre
of the scale. The second or bass line of striking begins at the usual distance
from the fret placed on the bridge, and is then progressively carried up in an
oblique direction to the last note of the bass. And in order to complete this

page_text: arrangement...I adopt a descending wire or other appropriate connection from
the end of each key, as is shown at Figure 2 of the Drawing, where one key
is shown with the necessary parts for giving inotion to the hammer; and the
only difference to be observed in respect to the other keys is, that the length
of the descending wire from the key will vary, according the position a par-
ticular hammer is required to strike its string. In constructing horizontal
pianos, the horizontal metal frame is constructed in a similar manner to the
one just described, except that it deviates in form as represented by the
Drawing B. It will be perceived that the same arrangement is carried out
to suit the same purposes, and the description above given to similar parts will
apply to this arrangement.
:
THE HORIZONTAL FRAME AS SHEWN IN DRAWING B.
(1) the left side supporter. (2) the right side supporter. (3) the upper
end supporters. (4) the partition supporters. (5) the stud bar: (6) the
screw bar. (7) the tension bar. (8) the square openings for the screw,
blocks. (9.) wood frame supporting the iron frame. (10) the legs.
(11) the
three partitions for the sound boards. I have not thought it necessary to
show any "action" to this piano forte, as those at present commonly in use
may be readily applied...
.::.2
Having thus described the nature of the various improvements, I would
remark, that although I have been exact in describing. every part, and the
various dimensions as practised by me, I do not .confine myself to. the. precise
details, so long as the peculiar character of either of my improvements be
retained.
In conclusion, I would shortly state that some of the. advantages derived
from the use of my improvements are, first, in the use of a complete metal
frame, which will be found better calculated than any kind of wood to sustain
the great degree of tension necessarily required, and the instrument so con-
structed will be found to stand well in tune, as the influence of varied tem
perature to which such piano fortes may be exposed will not. sensibly affect
the frame, whether in hot countries or otherwise; in addition to.which, great
durability is ensured. The peculiar construction of the sound boards of piano
fortes, and their being only attached to the frame at intervals; renders the
vibration free, and, being thus sustained, no obstacle can affect the wires
having their due influence on the sound boards, by which a greater degree
of purity and quantity of tone are obtained than can possibly be. produced
from the common arrangement of sound boards of piano fortes.The equality

page_text: of tone is also promoted by the foregoing arrangement, by increasing the
sphere of vibration and sympathy, which is carried in regular gradation from
the first sound bar a in the treble to the last in the bass. The arrangement
of the bridge being divided into butments, and in some cases into parts, and
each butment resting on the middle of each bar of the sound boards, the
vibration is not only extended above and below the bridge by the action of
the strings, but it is carried under each butment, when it is perfectly free to
yield its vibration, which is not the case where the bridge is fixed on the
sound board the whole of its length, as in the usual manner. The attachment
of the wires or strings, being fixed to the metal frame above and below, does
not interfere with the sound boards in any way to obstruct the freedom of
vibration, being perfectly independent of them, with the exception of resting
upon the bridge as they pass from fret to fret, thereby producing pressure
only where it is required to produce the necessary sympathy in the sound
boards; at the same time, by the secure and firm manner in which the wires
are fixed at either end, renders them immoveable when the instrument is
in tune, and by which arrangement the instrument can not only be tuned
with perfect simplicity, but in the highest possible degree of perfection, which
perfection it retains to an extraordinary length of time. The action striking
below is much more agreeable to the performer, removing all disagreeable
sound which might occur in the notion of the mechanism directly opposite
the face of the player, in the common manner. The instrument also being
open in the backs of the sound boards, the sound travels uninterruptedly, and
is heard at a greater distance.
I wish it to be understood, that I do not claim any of the mechanical parts
herein described when separately considered, and they may be varied so long
as my Invention or any of the parts thereof be retained. What I claim is,-
First, the mode of constructing piano fortes by applying metal frames in
substitution of wood, or wood combined with metal, as heretofore practised.
Secondly, I claim the mode of constructing sound boards of piano fortes
And I also
by applying sound bars & and posts y, as herein described.
claim the mode of applying sound boards on frames, and affixing such frames
at intervals to the iron frame which bears the strain of the strings, as above
described.
Thirdly, I claim the improved mode of applying bridges, as herein
described.
Fourthly, I claim the mode of stringing instruments as above described.
And, fifthly, I claim the mode of applying an action to upright piano fortes,
by causing the action to proceed downwards from the keys, when the