IMPROVEMENTS IN PIANOFORTES
Year: 1872

page_text: LETTERS PATENT to Henry Lockhart Gleig, of Guernsey, one of the
Channel Islands, Major, late of the Bengal Staff Corps, for the
Invention of "IMPROVEMENTS IN PIANOFORTES."
Invention of " IMPROVEMENTS IN PIANOFORTES."
Scaled the 22nd October 1872, and dated the 15th June 1872.
PROVISIONAL SPECIFICATION left by the said Henry Lockhart Gleig
at the Office of the Commissioners of Patents, with his Petition, on
the 15th June 1872.
I, HENRY LOCKHART GLEIG, of Guernsey, one of the Channel Islands,
Major, late of the Bengal Staff Corps, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN PIANOFORTES," to be as follows:-
My Invention has reference to upright pianofortes generally and to
such horizontal or grand pianofortes as have the downward struck action,
and has for its object the production of an increased power of tone in
such instruments by extending the sounding board beyond the striking
point throughout the whole width of the instrument, in the manner and
by the means herein-after stated.
In the Provisional Specification No. 3150 (1870) there is indicated a
former Invention of mine for a mode of effecting such extension of the
sounding board, and my present Invention consists in improved means
of accomplishing this object.

page_text: In my former Invention thus referred to the sounding board was
extending by diminishing the depth or width of the wrest pin block and
fixing to it one end or portion of a metal plate with a bridge cast on or
fitted to it, the opposite end or portion of the same plate being fixed to
the bracing by means of metal supports passed through apertures formed
in the sounding board and secured to the bracing, thereby leaving the
portion of the said plate between its fixing to the block and the said
supports (under or behind which the extended part of the sounding board
passed) without an adequate backing to prevent vibration.
Now my present Invention consists in giving to the said plate
increased solidity or power of resisting vibration by suitably backing up
that part of the plate which descends clear of the wrest pin block. And
this backing up of the plate is or may be effected by means of a series
of screw bolts screwed up through plates fixed between the bracings
until the said bolts are brought in contact with the said plate behind
or under which the sounding board is extended, the said bolts passing
through apertures formed in the sounding board without touching it,
and pressing against the back of the plate with a sufficient pressure
prevent its taking up the vibration to which it would otherwise be liable.
The said screw bolts arc so arranged as to follow as nearly as possible
the curve of the bridge on the said plate and block.
to
By the means above described the said plate is rendered quite solid
and all tendency to produce a hollowness of tone by its vibration is
obviated; also the stiffness of the block and its power to resist the effect
of tension is increased. Or similar results may be obtained by the use
of an entire cast metal frame, thereby dispensing with the supports of
the plate on the bracings. The requisite backing up of the said plate
may be otherwise effected if preferred so long as it does not interfere
with the duc action of the sounding board.
And my Invention has for its object in the second place the application
to the sounding board of an arrangement by means of which in the
event of the board sinking the normal pressure of the strings on the
belly bridge may be restored and the tone of the instrument brought
back. For this purpose there is fixed between the belly bridge and the
string plate a down bearing bridge by means of screws and a piece of
wood fixed to the sounding board, and following the curve of the belly
bridge. By means of the said screws and down bearing bridge the
requisite pressure on the belly bridge can be regulated and the tone
thereby restored.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Lockhart Gleig in the Great Seal Patent
Office on the 13th December 1872.
TO ALL TO WHOM THÉSE PRESENTS SHALL COME, I, HENRY
LOCKHART GLEIG, of Guernsey, one of the Channel Islands, Major, late
of the Bengal Staff Corps, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of June, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Henry Lockhart Gleig, Her special
licence that I, the said Henry Lockhart Gleig, my executors, adminis-
trators, and assigns, or such others as I, the said Henry Lockhart
Gleig, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
during the term therein expressed, 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
"IMPROVEMENTS IN PIANOFORTES," upon the condition (amongst others)
that I, the said Henry Lockhart Gleig, my exccutors or administrators,
by an instrument in writing under my, or their, or one of their hands
and seals, 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 Henry Lockhart Gleig, do hereby
declare the nature of my 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 Drawings here-
unto annexed, and to the letters and figures marked thereon (that is
to say):
My Invention of "Improvements in Pianofortes" has reference to
upright pianofortes generally, and to such horizontal or grand piano-
fortes as have the downward struck action, and has for its object
the production of an increased power of tone in such instruments by

page_text: extending the sounding board beyond the striking point throughout
the whole width of the instrument in the manner and by the means
herein-after stated.
In the Provisional Specification No. 3150 (One thousand eight hundred
and seventy) there is indicated a former Invention of mine for a mode
of effecting such extension of the sounding board, and my present
Invention consists in improved means of accomplishing this object.
In my former Invention thus referred to the sounding board was
extended by diminishing the depth or width of the wrest pin block and
fixing to it one end or portion of a metal plate with a bridge cast on or
fitted to it, the opposite end or portion of the same plate being fixed to
the bracing by means of metal supports passed through apertures formed
in the sounding board and secured to the bracing, thereby leaving the
portion of the said plate between its fixing to the block and the said
supports (under or behind which the extended part of the sounding
board passed) without an adequate backing to prevent vibration.
Now my present Invention consists in giving to the said plate
increased solidity or power of resisting vibration by suitably backing up
that part of the plate which descends clear of the wrest pin block. And
this backing up of the plate is or may be effected by means of a series
of screw bolts screwed up through plates fixed between the bracings
until the said bolts are brought in contact with the said plate behind
or under which the sounding board is extended, the said bolts passing
through apertures formed in the sounding board without touching it,
and pressing against the back of the plate with a sufficient pressure to
prevent its taking up the vibration to which it would otherwise be liable.
The said screw bolts are so arranged as to follow as nearly as possible
the curve of the bridge on the said plate and block. By the means
above described the said plate is rendered quite solid and all tendency
to produce a hollowness of tone by its vibration is obviated; also the
stiffness of the block and its power to resist the effect of tension is in-
creased. The strength of the whole frame is also increased by the mode
of fixing the string plate herein-after described. Or similar results as
to the backing up of the plate may be obtained by the use of an entire
cast metal frame, thereby dispensing with the supports of the plate on
the bracings. The requisite backing up of the said plate may be other-
wise effected if preferred so long as it does not interfere with the due
action of the sounding board.

page_text: sounding board, which is perforated as shewn in Fig. 2, in order to
admit of the standards D, D, passing freely through it as required. This
sounding board is extended upwards beyond the striking point the whole
width of the instrument, and is fixed at its upper end to the bottom part
of the wrest pin block B, as shewn in Fig. 1; and it is this extension of
the sounding board which requires the wrest pin block B to be diminished
in depth, and thereby causes the plate C to be liable to vibration in that
portion of it which descends below the wrest pin block, unless it is
backed up sufficiently to resist the same. This backing up of the
plate is effected under my present Invention by means of a series of
bolts, one of which is shewn at G, in Fig. 1. These bolts are screwed
up through plates H fixed between the bracings A, such plates being
fixed by means of screws as shewn to pieces of wood I, I, fastened to the
bracings with the grain endwise, and the said bolts G are screwed
through the plates H so as to press against the back of the plate O with
sufficient pressure to prevent its vibration, the said bolts also passing
freely through apertures formed in the sounding board.
The bolts G are arranged so as to correspond (or nearly so) with the
line of curvature of the bridge E at the back of the same, and they are
only required to be fixed so as to back up the plate C in that portion
of its length in which the plate C is unsupported by the wrest pin block.
This backing up of the plate, as is shewn at Fig. 3, is only required
to be done in four of the spaces between the bracings, that is to say,
behind the line of curvature of the bridge E which runs on the suspended
or unbacked part of the plate C.
By means of the said backing up of the plate C the tone of the instru-
ment is increased in brightness and clearness, and the rigidity and
strength of the plate with the vibratory action of the sounding board are
also increased.
The fitting and supporting of the plate C in the manner described
adds greatly to the firmness of the wrest pin block, and its capability of
resistance to any tendency to be pulled over.
The same effect may be produced by applying a cast or wrought-iron
frame to the front of the instrument, but I prefer the above-described
mode of accomplishing the object to the use of such frame, as it avoids
the defect of forming any break in the action or mechanism.
It is to be understood that the essential feature in this part of
my Invention is that of giving adequate stiffness and rigidity to the

page_text: suspended or unbacked part of the plate which carries the tenor and
treble bridge.
In combination with the above described mode of giving rigidity to
the plate and wrest pin block I dispense with what is usually termed
the bent side which generally carries the string plate in the tenor and
treble part of the instrument and into the rebate of which the sounding
board is fitted. In lieu thereof I fix one continuous metal string plate K
by means of strong metal shoes or standards L, L, which are let in and
screwed to the bracings A, and pass through the sounding board in a
similar manner to the standards D, D. The string plate is laid on the
shoes or standards L, L, and a bolt M. is passed through the string plate
and cach standard, and screwed up or tightened at the back of the
bracing. By this arrangement the excessive length of string from the
belly bridge to the bent side is avoided, and the distance between the
points of tension of the string being reduced the framing is less liable
to yield to the strain brought upon it; also by the mode described of
arranging and fixing the string plate the strain is distributed so that
each bracing is capable of taking its proportionate share of resistance
thereto. The string plate so fixed is an additional source of strength to
the whole frame of the instrument by forming a complete tic to the
bracings; and, further, by this arrangement the sounding board can be
extended below the belly bridge without impediment.
The said arrangement which has been described with reference to
upright pianofortes is applicable also to such horizontal or grand
pianofortes as have the downward struck action, the plate in such
cases being backed as required vertically instead of horizontally, as
described.
In Figures 1 and 2 is also represented the means by which the tone
of all kinds of pianofortes may be restored after it has become impaired
by the sinking of the sounding board, to which all instruments are
liable. N is a thin piece of hard wood fastened to the sounding board,
and following the shape of the curve of the belly bridge O. This piece
of wood is by preference fitted as near to the bridge as convenient, and
about half way between the string plate K and the bridge. An ordinary
metal or wood pressure bridge P, similar to those used on the block
bridge, is then applied between every two notes as may be necessary,
and this bridge P is then screwed down into the slip of hard wood N,
thereby drawing up the sounding board, and enabling the string on the

page_text: belly bridge to receive an amount of down bearing or pressure sufficient
to restore the tone to the instrument. By this means a different degree
of pressure can be applied to the different parts of the instrument as
may be required.
Having thus described the nature of the said Invention, and in what
manner the same is to be performed, I hereby declare that what I claim
as of my Invention is,—
First. The production of an increased vibratory and sustained effect
in the tone of the instrument by the method described of extending the
sounding board in combination with the special construction and backing
up of the plate, as described.
Secondly. The increased strengthening of the frame of the instrument
by the method described of arranging and fixing the string plate in
combination with the extension of the sounding board and backing up
of the plate in the manner described.
And lastly. The rostoration of the tone to pianofortes by fixing to
the sounding board a second bridge, and applying thereto a down
bearing or pressure bridge, and drawing up the sounding board, as
described.
In witness whereof, I, the said Henry Lockhart Gleig, have here-
unto set my hand and seal, the Thirteenth day of December, in
the year of our Lord One thousand eight hundred and seventy-
two.
Witness,
WILLIAM SPENCE,
8, Quality Court,
Chancery Lane.
H. L. GLEIG. (L.S.)