IMPROVEMENTS IN REGULATING DIGITORUMS,' PIANOS, HARMONIUMS, &C
Year: 1880

page_text: LETTERS PATENT to Thomas Story Horn and William Wilson Horn, of Elgin
Road, Croydon, in the County of Surrey, for an Invention of "IMPROVEMENTS
IN REGULATING DIGITORUMS,' PIANOS, HARMONIUMS, &C."
PROVISIONAL SPECIFICATION left by the said Thomas Story Horn and
William Wilson Horn at the Office of the Commissioners of Patents on the
21st February 1880.
THOMAS STORY HORN and WILLIAM WILSON HORN, of Elgin Road, Croydon,
Surrey. "IMPROVEMENTS IN REGULATING DIGITORUMS, PIANOS, HARMONIUMS,
&c."
The object of this Invention is to strengthen and develope the muscles of the
fingers of pianoforte players and others. The Invention is employed in the con-
struction of keyboard instruments, such as pianos, organs, harmoniums, &c., and also,
for the convenience of those persons who require a separate and cheaper instrument,
in the manufacture of our "improved regulating digitorums."
Our improved regulating digitorum may be briefly described as a case containing
a keyboard, on or underneath which are sliding springs, whereby with one and the
same instrument several degrees of resisting power are obtained, varying from a very
light to a very heavy touch. Another main feature of our Invention consists in an
arrangement for regulating the depth of touch of the keys by means of a key rail,
which is pressed on the top or above the keys. The case of our improved regulating
digitorum is made of wood or other suitable material, and its breadth depends on
the number of keys or notes required, which may be from a single note to the full
compass of a piano; each key has a groove underneath for the spring to travel in.
Adapting our Invention to a piano, these grooves are either on the top or under-
neath the keys. At the front of each key is the usual guide-pin, but we dispense
with the ordinary piano centre-pin, and in all our keyboards for improved regu-
lating digitorums, pianos, harmoniums, organs, &c., we cause each key to work on a
cross metal or wooden bridge above, attached to and forming part of a rail called
the centre rail, which extends across the keyboard from side to side, each key
working on a separate bridge, and the bridges being fixed to or forming part of the
centre rail. Sliding in a groove or grooves at the bottom of the case is a rail called
the spring rail, to which metal springs are attached. The spring rail is moved by

page_text: means of a screw at the back or in front of large improved regulating digitorums,
pianos, harmoniums, &c., and this screw is turned by a key; in smaller and cheaper
improved regulating digitorums the spring rail is moved by means of a thumbscrew
or other projection underneath the case. The key aforesaid being applied to a screw
or screws on the key rail, which extends across the keyboard and is fixed to each
side by means of a metal hinge, raises or lowers the keys or notes of the instrument,
thus affording a variation in the depth of touch. In the smaller and cheaper
improved regulating digitorums, in which we dispense with a key, the keyrail is
raised or lowered by two or more thumbscrews. When it is required to make the
improved regulating digitorum a musical instrument we insert reeds or vibrators
underneath the keyboard.
By means of our improvements in regulating digitorums, pianos, harmoniums,
&c., great facility of fingering and perfect execution may be obtained. The performer
begins to practise with resisting notes equivalent to the lightest piano touch, and as
the spring rail is moved from time to time the muscles of the fingers become so
admirably developed as to enable him to practise with a resisting power equivalent
to a heavy weight. The result is, the performer is in a position to render piano
and forte with the greatest facility without using pedals. The muscles of the fingers
are further developed by increasing the depth of touch. In order to show the
progress made we insert an index, on which a pointer travels as the springs are
moved.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Thomas Story Horn and William Wilson Horn in the Great Seal
Patent Office on the 20th August 1880.
THOMAS STORY HORN and WILLIAM WILSON HORN, of Elgin Road, Croydon,
in the County of Surrey. "IMPROVEMENTS IN REGULATING DIGITORUMS,' PIANOS,
HARMONIUMS, &C."
The object of this Invention is to strengthen and develope, or to restore and
increase, the power of the muscles of the fingers of pianoforte players and others.
The Invention is employed by us in the construction of keyboard instruments, such
as pianos, organs, and harmoniums, and also (for the convenience of those persons
who require a separate and cheaper instrument) in the manufacture of our improved
regulating digitorums.
Our improved regulating digitorum may be briefly described as a case made of
wood or other suitable material enclosing a keyboard, on or underneath which are
sliding or travelling springs, which on being moved to and fro in the manner
hereinafter described cause the resistance of the keys to vary from a very light to a
very heavy touch. We accomplish this in the following manner :-At the front of
each key is the usual guide pin, but we dispense with the ordinary centre pin, and
in all our keyboards make each key work on a bridge by means of a clamp, the
said clamp being screwed to the key, and the said bridge being attached to a rail
called the centre rail which extends across the instrument from side to side. The
aforesaid clamp and bridge form a fulcrum, which is placed in the centre of long
keys and at the end of short keys, as shown in Fig. 7 and Fig. 4. This mechanical
movement is applicable to pianos, organs, and harmoniums, independent of tho
sliding springs, which when pressure is desired travel each in a groove underneath
the short keys, or either on the top of the key behind the fulcrum or underneath in
front of the fulcrum in the long keys. The said springs are attached to a rail called
the spring rail, which is propelled by means of a screw, or simply by means of a
slide having a projection at the bottom of the instrument. In some of our digito-
rums, and also in pianos, organs, and harmoniums, we use the screw, which is turned
by means of a key. In other digitorums where it is not required we employ a
thumbscrew underneath the instrument to draw the spring rail to and fro; and to
prevent the springs running back, by practice with a heavy pressure, it is merely
necessary to tighten the thumbscrow aforesaid. The spring rail travels in a slide
or slides, according to the size of the instrument. In a small instrument, i.c., an
instrument of very small compass, we find one slide is sufficient; in larger instru-
ments more than one slide is required. Attached to the spring rail or the slide is a
pointer which shows on an index the progress made. The regulating of the depth
of touch of the digitorum keyboard is another main feature in our Invention. For
this purpose we construct a rail across the keys on the top called the key rail, which
is attached to each side of the instrument by means of a hinge. As this key rail is
raised or depressed the keys rise and fall from one eighth of an inch to seven eighths
of an inch, or more if required; and in order to keep the said key rail in any
position desired a metal rod which is fixed to the bottom of the instrument passes
up each side through the front part of the hinges of the key rail, and by means of
nuts the said rail is raised or depressed. A spiral spring under each hinge takes off
the pressure of the key rail. In larger instruments, above two octaves, we make
use of a stay or flat rod, which passes between the keys and is necessary, in addition
to the side rods, to keep the keys level. Each stay aforesaid has a nut like the side
rods described, which nut may be turned by hand or by the key used for the screw
attached to the spring rail. In the cheapest of our improved regulating digitorums
we regulate the pressure or resistance only, if required. When it is desired to make
our dumb instruments musical we add reeds or vibrators beneath the keyboard at

page_text: the front of the instrument, worked by means of a crank connecting the key and
the pallet.
Fig. 10 is the bridge previously described; Fig. 10, section of same.
Fig. 11 is the clamp; Fig. 114, section. Fig. 1 is a section of broad key used in
small digitorums where there are no sharps; E is the centre rail to which the bridge
F is attached; G is the clamp screwed to the key A, B, to keep it in position; the
dotted line H represents the groove in which the spring moves. Fig. 2 is a plan of
the same key. Fig. 3 is a front section showing the groove in the key. Fig. 4 is
a digitorum natural key used in instruments where sharps are employed; it is
consequently narrower and longer than the preceding key. Fig. 6 is a front section
showing the groove cut to receive the bridge. Fig. 7 is a piano koy with fulcrum
in the centre; the centre rail E is attached by each end to the side of the instru-
inent, and requires metal supports in the centro passing between the keys.
Figs. 8&9 represent the spring described as attached to the spring rail and working
in a groove in each key for the purpose of varying the resistance.
Having thus particularly described the nature of our said Invention, we claim,—
1st. The mechanical movement or fulcrum for keyboard instruments, as defined.
2nd. The means of regulating the resistance of the keys.
3rd. The means of regulating the depth of touch.
4th. The index.
5th. The musical digitorum previously described.
6th. The general arrangement of improvements in regulating digitorums, pianos,
harmoniums, &c., substantially in the manner and for the purpose herein-before set
forth and described.
In witness whereof, we, the said Thomas Story Horn and William Wilson
Horn, have hereunto set our hands and seals, this Twentieth day of August,
in the year of our Lord One thousand eight hundred and eighty.