IMPROVEMENTS IN THE ACTION OF PIANOFORTES
Year: 1859

page_text: LETTERS PATENT to Charles Jackson, of Store Street, Bedford Square, in
the County of Middlesex, Pianoforte Manufacturer, for the Invention of
"IMPROVEMENTS IN THE ACTION OF PIANOFORTES."
Sealed the 26th July 1859, and dated the 11th February 1859.
PROVISIONAL SPECIFICATION left by the said Charles Jackson at the
Office of the Commissioners of Patents, with his Petition, on the 11th
February 1859.
I, CHARLES JACKSON, of Store Street, Bedford Square, in the County of
Middlesex, Pianoforte Manufacturer, do hereby declare the nature of the
Invention for "IMPROVEMENTS IN THE ACTION OF PIANOFORTES," to be as
follows:-
This Invention has for its object improvements in the action of pianofortes.
In order to obtain the escapement of the fly or hopper, I fix to the front of it
at right angles, or nearly so, a straight projecting piece, the end of which
comes underneath a stop carried by a stem fixed in the block on which the
fly or hopper is mounted; this stop is adjustable by a screw, and by means of
it the fly or hopper can be arranged to escape at the proper time from the
hammer or other instrument on which it acts. Below the projection from the
fly or hopper I sometimes place another adjustable stop, also mounted on the
block carrying the hopper; this second stop is employed in substitution
of the rail ordinarily used, to prevent the flys or hoppers from falling farther
from the hammers or instruments on which they act than is necessary. This
arrangement is applicable to grand, square, and upright pianos.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Jackson in the Great Seal Patent Office on the
11th August 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
JACKSON, of Store Street, Bedford Square, in the County of Middlesex,
Pianoforte Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of February, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Charles Jackson, Her special licence that I, the said. Charles Jackson,
my executors, administrators, and assigns; or such others as 1, the said Charles
Jackson, 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 THE ACTION OF PIANOFORTES," upon the condition (amongst others) that I,
the said Charles Jackson, 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 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 Charles Jackson, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say :-
.
This Invention has for its object improvements in the action of pianofortes.
In order to obtain the escapement of the fly or hopper, I fix to the front of it,
at right angles or nearly so, a straight projecting piece, the end of which comes
underneath a stop, carried by a stem fixed in the block on which the fly or
hopper is mounted; this stop is adjustable by a screw, and by means of it the
fly or hopper can be arranged to escape at the proper time from the hammer
or other instrument on which it acts. Below the projection from the fly or
hopper, I sometimes place another adjustable stop, also mounted on the block
carrying the hopper; this second stop is employed in substitution of the rail
ordinarily used to prevent the flys or hoppers from falling farther from the

page_text: hammers or instruments on which they act than is necessary. This arrange-
ment is applicable to grand, square, and upright pianofortes.
And, in order that my said Invention may be most fully understood, and
readily carried into effect, I will proceed to describe the Drawing hereunto
annexed.
DESCRIPTION OF THE DRAWING.
The Drawing shows a side view of a fly or hopper, with the parts connected
with it arranged according to my Invention. a is the fly or hopper jointed in
the usual manner to a block b, which is ordinarily carried by the key lever; c
is a projection fixed to the front of the fly or hopper; the end of this projection
comes underneath the stop d on the stem e fixed in the block b, and the
projection c is pressed up towards this stop by the spring f, which bears on the
fly or hopper and forces it towards the hammer or other part on which it may
be arranged to act; g is a stop to prevent the fly or hopper moving too far
from the hammers or other instruments when the escape takes place; the
stop g is mounted on the same stem as the stop f, and is capable of being
adjusted in its position in the same manner as this stop. The stops f of the
flys or hoppers are employed in place of the rail ordinarily used to limit the
motion of the flys or hoppers, and which projects all across the instrument in
front of the flys or hoppers; by employing stops the flys or hoppers may be
separately adjusted, which cannot be done when a rail is used, and all
difficulties arising from the warping of the rail are avoided.
In witness whereof, I, the said Charles Jackson, have hereunto set
my hand and seal, this Eleventh day of August, in the year of our
Lord One thousand eight hundred and fifty-nine.
CHARLES JACKSON. (L.S.)