AN IMPROVEMENT IN PIANOFORTES
Year: 1860

page_text: LETTERS PATENT to William Edward Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Civil Engineer, for
the Invention of "AN IMPROVEMENT IN PIANOFORTES."-A communication
from abroad by Spencer Bartholomew Driggs, of New York, in the
United States of America.
Sealed the 27th September 1860, and dated the 17th April 1860.
PROVISIONAL SPECIFICATION left by the said William Edward Newton
at the Office of the Commissioners of Patents, with his Petition, on the
17th April 1860.
I, WILLIAM EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane,
in the County of Middlesex, Civil Engineer, do hereby declare the nature of
the said Invention for "AN IMPROVEMENTS IN PIANOFORTES," to be as follows:-
This Invention of an improvement in pianofortes consists in what is termed a
graduated sound-board and bridge, that is to say, in so arranging and applying
the sound-board and strings and so constructing and applying the bridge or
bridges of a pianoforte, that the depth of bridge at the bearing points of the
several strings and the distances of the several strings from the board are in
proportion, or nearly so, to the lengths of the vibrating portions of the strings.
The pianoforte has its external form substantially like that in which grand
pianofortes are ordinarily constructed, but has its strings and tuning block

page_text: sustained in place by means of an iron frame, which may or may not be
independent of the sides of the case. The case is composed of a strong bottom
frame, and a mere shell of wood, whose bottom is made very thin to constituto
an extra sound board. The iron string frame is supported by means of
blocks at each side of its front end, and posts at its rear end. The Invention
is however applicable to pianofortes of ordinary construction as well as to
those constructed as above specified.
The improved or graduated sound-board is intended to be used instead
of the sound-board commonly employed, and two graduated bridges are made
to rest on the sound-board and support the strings, the longer bridge supports
the lower tier of strings, and the shorter but deeper bridge supports the
heavier strings of the lower notes, and which strings constitute an upper tier.
The sound board is made parallel or as nearly so as practicable or convenient
to the length of the strings, so that every portion of each string may be as
nearly as possible at the same distance from it, but its peculiarity, which
entitles it to be termed a graduated sound-board, consists in its being
arranged with a gradual descent from the side or end which is under the
shortest string to the side or end which is under the longest string. This
descent may be straight or with a curvature that will bear a proper relation
to the horizontal curvature of the bridges to obtain a depth of bridge at the
bearing point of every string, and a distance between every string and the
sound-board in proportion, or very nearly so, to the length of the vibrating
portion of the string, and to the diameter of the circle described by it in its
vibrations. The bridges for the purposes of the present Invention being for
the most part of greater depth than the bridges ordinarily employed, are
built up of several pieces in some convenient manner, and they should be
lightened so as not to interfere too much with the vibration of the sound-board
by having transverse openings cut in them.
The strings are arranged in two tiers, one tier being arranged obliquely in
one direction to the hammer line, and the longer strings of the lower tier
are arranged obliquely to the hammer line in the opposite direction, the
back end of the longest of the last-mentioned strings coming near to the side
of the string frame. This arrangement allows the greatest length of string
and the greatest distance between the strings, and at the same time admits
of all the strings being brought at equal distances a part in a horizontal
direction throughout the whole scale.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Edward Newton in the Great Seal Patent Office
on the 16th October 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
EDWARD NEWTON, of the Office for Patents, 66, Chancery Lane, in the County
of Middlesex, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventeenth day of April, in the year of our
Lord One thousand eight hundred and sixty, in the twenty-third year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me
the said William Edward Newton, Her special licenso that I, the said
William Edward Newton, my executors, administrators, and assigns, or
such others as I, the said William Edward Newton, my executors, adminis-
trators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein ex-
pressed, 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 "AN IMPROVEMENT IN PIANOFORTES," being
a communication from abroad, upon the condition (amongst others) that
I, the said William Edward Newton, by an instrument in writing under
my hand and seal, 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 William Edward Newton, 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 Drawing hereunto annexed,
and to the letters and figures marked thereon (that is to say): :-
This Invention of an improvement in pianofortes consists in what is termed
a graduated sound-board and bridge (that is to say) in so arranging and
applying the sound-board and strings and so constructing and applying tho
bridge or bridges of a pianoforte, that the depth of bridge at the bearing
points of the several strings, and the distances of the several strings from
the board are in proportion or nearly so to the lengths of the vibrating portions
of the strings.
In the accompanying Drawing, Fig. 1 exhibits a longitudinal vertical
section of a grand pianoforte; Fig. 2 is a transverse vertical section of the.

page_text: same, and Fig. 3 a plan of the interior of the same.
reference indicate corresponding parts in the several Figures.
Similar letters of
The pianoforte has its external form substantially like that in which
grand pianofortes are ordinarily constructed, but has its strings c, c, and d, d,
and tuning block D sustained in place by means of an iron frame B, which
nay or may not be independent of the sides of the case. The case is composed
of a strong bottom frame A, and a mere shell of wood whose bottom C is
made very thin to constitute an extra sound-board. The iron string frame B
is supported by means of blocks at each side of its front end and posts a, a,
at its rear end. The Invention is however applicable to pianofortes of
ordinary construction as well as to those constructed as above specified.
The improved or graduated sound-board E is intended to be used instead
of the sound-board commonly employed, F and G are two graduated bridges
resting on the sound-board E and supporting the strings, the longer bridge F
supports the lower tier of strings c, c, and the shorter but deeper bridge G
supports the heavier strings d, d, of the lower notes, and which strings
constitute an upper tier. The sound-board is made parallel or nearly so as
practicable or convenient to the length of the strings so that every portion of
cach string may be as nearly as possible at the same distance from it, but its'
peculiarity which entitles it to be termed a graduated sound-board consists in
its being arranged with a gradual descent from the side or end which is
under the shortest string, to the side or end which is under the longest string,
as is shown in the transverse section Fig. 2. This descent may be straight
or with a curvature that will bear a proper relation to the horizontal curvature'
of the bridges F, G, to obtain a depth of bridge at the bearing point, of every
string, and a distance between every string and the sound-board in proportion or
very nearly so, to the length of the vibrating portion of the string, and to the
diameter of the circle described by it in its vibrations. The proper depth
of bridge and distance between the string and sound-board is found by
experiment to be about one-cighth of the length of the vibrating portion of the
string; but this will vary somewhat according as the thickness of the string is in
proportion to its length, a thicker string requiring a less depth of bridge and
distance from sound-board. The bridges F and G being for the most part
of greater depth than the bridges ordinarily employed, are built up of several
pieces in some convenient manner, such for instance as is represented in
Fig. 1 and indicated by f, f, g, h; but I do not confine myself to this construction
and they should be lightened (so as not to interfere too much with the vibration
of the sound-board) by having transverse openings i, i, cut in them, such
openings being of the elliptical form represented, or of upright arched form

page_text: leaving the bridge supported on the board by a number of narrow piers.
By graduating the sound-board and bridges as described (that is to say)
making the distances between the strings and sound-board and the depth of
bridge in proportion to the length of the strings and their circles of vibration,
a perfectly free and unchecked vibration is permitted to every string and a
purity of tone is obtained throughout the whole scale, which cannot be
approached in an instrument where the sound-board is at the same distanco
from every string as in the pianofortes heretofore constructed.
The arrangement of the two tiers of strings is best shewn in the plan view of
Fig. 8. The upper strings d, d, are all arranged obliquely in one direction to
the hammer line x, x, and the longer strings of the lower tier are arranged
obliquely to the hammer line in the opposite direction, the back end of the
longest of the last-mentioned strings coming near to the side of the string
frame B. This arrangement allows the greatest length of string and the
greatest distance between the strings, and at the same time admits of all the
strings being brought at equal distances apart in a horizontal direction through-
out the whole scale. An opening k, k, is provided in the string plate B, for
the bridge G to pass through. It may be observed in Fig. 3, that the longest
of the strings c, c, is longer than the shortest of the strings d, d, but tho
latter are covered or loaded strings.
Having now described the Invention of an improvement in pianofortes,
that has been communicated to me by my foreign correspondent, and having
explained the manner of carrying the same into effect, I claim as the Invention
secured to me by Letters Patent as aforesaid, the mode herein set forth of
constructing pianofortes and of so arranging and applying the sound-board
in relation to the strings, and constructing the bridge or bridges that the
depths of the bridge or bridges at the bearing points of the strings and the
distances of the several strings from the board are in proportion or nearly so to
the length of string as herein described.
In witness whereof, I, the said William Edward Newton have hereunto
set my hand and seal, the Thirteenth day of October, in the year
of our Lord One thousand eight hundred and sixty.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
W. E. NEWTON. (L.S.)