CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF PIANOPORTES
Year: 1845

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
HATTERSLEY, of Regent Street, Westminster, Pianoforte Manufacturer; 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 Seventh day of April, in the eighth year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said
William Hattersley, Her especial license, full power, sole privilege and autho-
rity, that I, the said William Hattersley, my executors, administrators, and
assigns, and such others as I, the said William Hattersley, my executors,
administrators, 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 men-
tioned, should and lawfully might make, use, exercise, and vend, within
England, Wales, the Town of Berwick-upon-Tweed, and in all Her Majesty's
Colonies and Plantations abroad, and in the Islands of Jersey, Guernsey,
Alderney, Sark, and Man, my Invention of "CERTAIN IMPROVEMENTS IN
THE CONSTRUCTION OF PIANOPORTES;" in which said Letters Patent is contained
a proviso obliging me, the said William Hattersley, by an instrument in
writing under my hand and seal, particularly to describe and ascertain the
nature of my said Invention, and in what manner the same is to be per-
formed, and to cause the same to be inrolled in Her 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 more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, 1, the said
William Hattersley, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, is particularly described
and ascertained in and by the following description thereof, reference being
had to the Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say) :-
My improvements in the construction of pianofortes consist in a peculiar
method of strengthening the framing which carries the strings by the appli-
cation of metallic elastic trusses. By this novel construction I am enabled
to overcome the difficulty which has been so generally felt by pianoforte
makers, viz, the bending of the framing consequent upon the contraction of
the strings. To prevent this bending of the frame, which is exceedingly
detrimental to the tone of the instrument, and which frequently starts the
joints of the casing, it has been found necessary to increase the strength
of the wood bracings to a degree sufficient to resist the pull of the strings;
but, as the substance and tension of the strings of pianofortes have latterly
been considerably increased, the difficulty of keeping the framing to its
original shape has proportionably augmented.
In order that my Invention may be clearly understood, I have shewn in the
accompanying Drawings several modifications of my plan of strengthening the
framing which carries the strings of a pianoforte, which modifications are
made to adapt the principle of the Invention to the different kinds of upright
or horizontal instruments now manufactured, whether the bracing be
perpendicular or oblique to its framing.
Fig. 1 is a sectional elevation of a cottage pianoforte with my improve-
ments applied thereto, and Fig. 2, is a back view of the same. A, A, is
the ordinary framing, which is strengthened; B, B, B, are the braces, and
C, C, (Fig. 1, represents the position of the strings and the mode of attaching
them to the top and bottom bars of the framing A, A. It will now be
perceived, that if the strings contract they will draw with them the top and
bottom bars of the framing, and the vertical braces B will be brought more or
less into the form of a hollow bow or arch. The continued pull of the wires
(generally increased by tuning) has a tendency to increase this bow or arch:
therefore, to counteract this tendency of the bracing to bend, I propose to
apply metal rods D, D, which pass over two transverse bars E, E, and enter
the top and bottom rails of the framing A, A, as represented in the Drawing.
One end of each of these rods is furnished with a boss or head, and the other
is tapped to receive a nut. F is an angle plate extending along the face and
bottom of the lower rail of the framing, and G is a plate extending along the

page_text: upper edge of the top rail of the framing, as shewn more fully in the horizontal
top view at Fig. 3. These plates are to receive the strain of the rods D when
they are screwed up to their proper tension by means of the nuts d. The
whole, thus constructed, forms an elastic truss power, the force of which is
exerted in counteraction of the pull of the strings. If it should happen to be
necessary to increase this counteracting force, it will only be requisite to turn
the nuts d.
I have not thought it necessary to shew my improvements adapted to a
cabinet pianoforte, as the construction is precisely similar to that just ex-
plained. It will be obvious, that instead of a nut and screw to tighten the
rods, a wedge driven through a mortice hole in the end of the rod (see the
detached view, Fig. 4) will have the same effect.
The mode of adapting my Invention to a "grand pianoforte will be seen
by referring to Figures 5, 6, 7, and 8, Fig. 5 being a plan of the under side
of the framing which carries the strings, and Fig. 6 a vertical section taken in
the line (y, z,) of Fig. 5. Fig. 7 is also a vertical section, taken transversely
through what is called the well hole of the instrument in the line (W, X,) of
Fig. 5, shewing the belly rail H, II. Fig. 8 is a horizontal view of the front
part of the instrument, taken on the upper side, shewing the wrest block I, I,
and the well hole with the top arches e, e, e, which connect the wrest block to
the belly rail and rods D. These parts are more clearly seen in the enlarged
sectional Figure 9, which is taken vertically through the front part of the
instrument, and is also seen in Fig. 6. Fig. 10 represents one of the top
arches e detached. Figs. 11 are two views of the under arches which connect
the under part of the wrest block with the belly rail and rods D, as shewn in
Fig. 9, in the manner and upon the principle before described.
Figures 12, 13, 14, and 15, shew the adaptation of my improved elastic
trusses to square pianofortes, or others in which the braces are placed
diagonally.
Having now described my improvements in pianofortes, and the modes of
dapting them to various kinds of instruments, I desire it to be understood that
I do not intend to claim any other feature of novelty in the construction of
ianofortes except the adaptation of metallic trusses, in the manner above
escribed, for the purpose of affording strength and an adjustable tension to
he frame or bracing and strings of such kinds of musical instruments.
In witness whereof, I, the said William Hattersley, have hereunto set
my hand and seal, this Seventh day of October, in the year of our
Lord One thousand eight hundred and forty-five.
WILLIAM (L.s.) HATTERSLEY.

page_text: AND BE IT REMEMBERED, that on the same Seventh day of October,
in the year above mentioned, the aforesaid William Hattersley came before
our Lady, the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained, in form above written.
And also the Specification aforesaid was stamped according to the tenor of
the Statute in that case made and provided.