IMPROVEMENTS IN THE MEANS OF AND APPARATUS FOR DEVELOPING OR EXTENDING THE POWERUND OF PIANOFORTES OR OTHER SIMILAR KEYED INSTRUMENTS
Year: 1867

page_text: LETTERS PATENT to Robert William Pearse, of Lewisham Road, Green-
wich, in the County of Kent, for the Invention of "IMPROVEMENTS IN
THE MEANS OF AND APPARATUS FOR DEVELOPING OR EXTENDING THE POWER
Sealed the 15th May 1868, and dated the 16th November 1867.
PROVISIONAL SPECIFICATION left by the said Robert William Pearse
at the Office of the Commissioners of Patents, with his Petition, on
the 16th November 1867.
I, ROBERT WILLIAM PEARSE, of Lewisham Road, Greenwich, in the County
of Kent, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN THE MEANS OF AND APPARATUS FOR DEVELOPING OR EXTENDING THE POWER
OR SOUND OF PIANOFORTES OR OTHER SIMILAR KEYED INSTRUMENTS," to be as
follows:-
This Invention relates to certain improvements in the means of and
apparatus for developing or extending the power or sound of pianofortes,
harmoniums, organs, and other similar keyed instruments, whereby the tone
of the instrument is considerably strengthened, and the effect of a carpeted
room which it is well known deadens the sound or vibration is completely
counteracted.
The apparatus consists of a hollow case of wood or other material made of
the width of the pianoforte or other instrument, so that the feet of the instru-
ment may rest or stand on the margin or border. The case is made somewhat

page_text: on the principle of the violin, and stands on four blocks of ebonite, vulcanite,
or other non-conducting material, and is at an elevation of about an inch
and a half from the floor. The top or upper surface of the case is of a convex
form and perforated with six or other number of holes, and between each hole
on the internal side of the case a sounding post is fixed.
By the application of this apparatus to the feet of pianofortes or other similar
keyed instrument it is evident that the resonance or vibration of musical sounds
will be materially increased, and the tone of the instrument thoroughly
developed. The apparatus is also serviceable on a stage or in a concert room
acting as a perfect insulator of sound between the instrument and the floor,
and thus causing the entire power of sound to be given out instead of its
being partially absorbed by the conduction afforded by the contact of the feet
of the instrument with the carpet or floor.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Robert William Pearse in the Great Seal Patent Office on
the 16th May 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ROBERT
WILLIAM PEARSE, of Lewisham Road, Greenwich, in the County of Kent, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixteenth day of November, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Robert William Pearse, Her special licence that I, the said Robert
William Pearse, my executors, administrators, and assigns, or such others as
I, the said Robert William Pearse, 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 "IMPROVE-
MENTS IN THE MEANS OF AND APPARATUS FOR DEVELOPING OR EXTENDING THE POWER
OR SOUND OF PIANOFORTES OR OTHER SIMILAR KEYED INSTRUMENTS," upon the con-
dition (amongst others) that I, the said Robert William Pearse, my executors 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

page_text: 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 Robert William Pearse, 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 :-
My Invention relates to certain improvements in the means of and apparatus
for developing or extending the power or sound of pianofortes, harmoniums,
organs, and other similar keyed instruments, whereby the tone of the instrument
is considerably strengthened, and the effect of a carpeted room which it is well
known deadens the sound or vibration is completely counteracted.
The apparatus consists of a hollow case of wood or other material made
about the width and depth or length of the pianoforte or other instrument so
that the feet or castors of the instrument may rest or stand on the margin or
border. The case is made somewhat on the principle of the violin, and stands
on four blocks of ebonite, vulcanite, or other non-conducting material, and
is at an elevation of about an inch and a half from the floor. The top or upper
surface of the case is of a convex form and perforated with holes or apertures,
and between each hole or aperture on the internal side of the case a sounding
post is fixed.
By the application of this apparatus to the feet of pianofortes or other similar
keyed instruments it is evident that the resonance or vibration of musical
sounds will be materially increased and the tone of the instrument thoroughly
developed. The apparatus is also serviceable on a stage or in a concert room
acting as a perfect insulator of sound between the instrument and the floor,
and thus causing the entire power of sound to be developed instead of its being
partially absorbed by the conduction afforded by the contact of the feet of the
instrument with the carpet or floor.
For grand pianofortes the insulating apparatus is made of a corresponding
shape to admit of the reception of the feet or castors.
In order that my said Invention may be completely understood, I annex
the accompanying Drawings which will illustrate the best methods with which
I am acquainted for carrying out the principles of the Invention.
Fig. 1 shews a plan view of the insulator suitable for a cottage pianoforte,
and Fig. 2 an under plan view.
a, a, represents the top plate of the foundation or base of the apparatus,
which is hollow throughout except at the sides and at the positions of the
supports or stays and the sounding posts. In Fig. 1, 6 represents the bridge
belly or sounding board, which is set in dovetails cut in the top fixed plate a

page_text: perforated with two scrolls and an aperture c, c, c, the sounding posts supporting
the bridge and fixed beneath it, and above the base of the foundation are shewn in
dotted lines at d, d, and e, e, are the cross bars intervening between the sounding
bridge and internal surface of the base; the dotted lines f. f, shew the square
insulating spaces divided off from the sounding board by partitions 9, g; and
within these and on the under surface of the top plate of the apparatus, beyond
the limit of the sounding bridge the castors are attached (see Fig. 2 shewing
the under plan view) by means of the intervention of a sheet of india.rubber,
vulcanite, ebonite, or other non-conducting material which is placed under the
top plate, and the castor is then screwed thereon and to the top plate. By
the intervention of the insulating material, the sound or vibration of the
instrument is maintained and prevented from conduction to the floor of the
apartment. The dotted lines g¹, g¹, Fig. 1, shew further supports between
the upper and lower plates of the apparatus, these divisional pieces also
serve materially to assist in the increase of the vibratory power of the
insulator.
Fig. 3 shews an insulator made on the same principle but suitable for a
grand pianoforte; a, a, shew the base or foundation; b, the sounding bridge;
and c, c, c, the scrolls and circular aperture. The sounding posts are shewn
at d, d, and the divisions or supports for the insulating spaces for the castors
or bearings are shewn at f, f. The semicircular or oval recess cut out in the
apparatus is to allow room for working the pedals. Instead of applying the
non-conducting material between the castor and the base plate, several pieces or
layers of insulating substance may be fastened under the apparatus so as to
form a sufficient thickness to raise it above and free from the floor without
the application of castors. Or the entire area of the apparatus may be covered
with the said insulating substances, thus also dispensing with castors or other
supports. The pianoforte or other instrument may be placed on the apparatus
with or without the aid of guides or stays for the castors, and may be made a
fixture to the instrument by brackets or other equivalent means, or tramways, or
guiding grooves may be attached to the apparatus for securing the castors of
the piano in position. The entire apparatus may be made of metal, or the
bridge may be of metal and the foundation of wood, or vice versa.
Having now described the nature of my said Invention, and the manner in
which the same is to be performed, I would remark in conclusion that ] do
not limit myself to the precise details and configuration of parts I have
expressed and shewn, as the same may be varied or modified without departing
from the principles on which the Invention is founded; but what I claim and
desire to be secured to me by the herein in part recited Letters Patent is, the

page_text: construction of the apparatus consisting of a hollow foundation or base and
sounding board or bridge and the other accessories, such as the partitions,
sounding posts, and insulated castors or other insulated supports applicable to
pianofortes or other similar keyed instruments for the purpose of developing or
extending their power or sound, substantially as herein specified and shewn.
In witness whereof, I, the said Robert William Pearse, have hereunto
set my hand and seal, this Fifteenth day of May, in the year of our
Lord One thousand eight hundred and sixty-eight.
Witness,
ALEX. C. M. PRINCE,
Office for Patents,
4, Trafalgar Square,
Charing Cross.
ROBT. W. PEARSE. (L.B.)