AN IMPROVED PORTABLE PIANOFORTE DIGITORIUM
Year: 1874

page_text: LETTERS PATENT to William Mead, of Aston, Wallingford, in the
County of Berkshire, for the Invention of "AN IMPROVED PORTABLE
PIANOFORTE DIGITORIUM."
Sealed the 16th April 1875, and dated the 20th October 1874.
'PROVISIONAL SPECIFICATION left by the said William Mead at the
Office of the Commissioners of Patents, with his Petition, on the
20th October 1874.
I, WILLIAM MEAD, of Aston, Wallingford, in the County of Berkshire,
3 do hereby declare the nature of the said Invention for "AN IMPROVED
PORTABLE PIANOFORTE DIGITORIUM," to be as follows :—
This Invention has for its object the constructing an improved portable
pianoforte digitorium in such a manner that when played upon it will
emit musical sounds somewhat resembling those produced by a musical
hox.

page_text: The principle hitherto adopted of constructing the instrument known
as a digitorium, so that the pupil has been unable to elicit any musical
sounds therefrom is attended with considerable disadvantage, since it not
only renders the use thereof a very monotonous exercise, but also
entirely fails to develope any faculty in the ear to distinguish the various
notes by their individual sounds, and thereby the student is unable to
acquiro by means of the practice thereof, either delicacy of touch or a
varied expression by a skilful manipulation of the keyboard.
Now I propose to overcome these disadvantages in the following
way:-I make a keyboard similar to that of a pianoforte and of any
desired compass, say one, two, or three octaves, and under each of such
keys I place a small spiral spring, or it may be of any other suitable
shape to ensure such key returning to its normal position after it has
been depressed by the student's finger. About midway of such key, and
just beneath the ordinary orifices usually formed therein for the reception
of the pin which secures it in its proper place on the keyboard, I fasten
by means of a screw or otherwise a small metal hook which is left
sufficiently loose to ensure its playing easily up and down. To the
upper end of each key I affix a small wheel one-half of the circumference
of which is cogged, whilst the remaining half thereof is furnished with
small metal pins corresponding to those on the barrel of a musical box.
I secure such wheel to the upper end of the key by means of a metal
rod upon which the wheel revolves freely. Such metal rod extending
the entire length of the instrument, and thus both serving as an axis
whereon any desired number of wheels may revolve, and also to secure
the upper ends of all the keys of the instrument in their proper position.
This wheel is caused to revolve by means of the small metal hook before-
mentioned gearing into its cogged circumference as the performer on
the instrument depresses the keys, whilst the small metal pins on the
other portion of its circumference are caused by such revolution to come
in contact with the teeth of a metal comb similar to that used in the
construction of a musical box, whereby an agreeable and suitable sound
is produced, thereby enabling the performer to judge if he is playing
correctly, at the same time that it imparts an attractive interest to his
studies.

page_text: ordinary dimensions of the width and length thereof need not exceed,
say about 2 feet long by 13 inches broad.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Mead in the Great Seal Patent Office on
the 19th April 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
MEAD, of Aston, Wallingford, in the County of Berkshire, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twentieth day of October, in the year
of our Lord One thousand eight hundred and seventy-four, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Mead, Her special license
that I, the said William Mead, my executors, administrators, and
assigns, or such others as I, the said William Mead, 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 "AN IMPROVED PORTABLE
PIANOFORTE DIGITORIUM," upon the condition (amongst others) that I, the
said William Mead, 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.

page_text: .P
This Invention has for its object the constructing an improved
portable pianoforte digitorium in such a manner, that when played upon
it will emit musical sounds somewhat resembling those produced by a
musical box.
The principle hitherto adopted of constructing the instrument known
as a digitorium, so that the pupil has been unable to elicit any musical
sounds therefrom is attended with considerable disadvantage, since it
not only renders the use thereof a very monotonous exerciso, but also
entirely fails to develop any faculty in the ear to distinguish the various
notes by their individual sounds, and thereby the student is unable to
acquire by means of the practice thereof either delicacy of touch or a
varied expression by a skilful manipulation of the keyboard.
.
Now I propose to overcome these disadvantages in the following
way :-I make a keyboard similar to that of a pianoforte or harmonium
shewn at a, Figure 1, of the accompanying Drawing (a', Figure 1
shewing an ordinary pianoforte key, and a³, Figure 1, the felt washer
beneath the same, and a³, the metal pegs), and of any desired compass, say
two, three, or more octaves, and I either fix a small spring or elastic
band c, Figure 2, to the upper part of the key, and suspend it to a
wooden bar running the whole length of the instrument, as shewn on
the Drawing at 6, Figure 1; or I place under each of such keys a small
spiral spring, or it may be of any other suitable shape, either of which
plans is to ensure the key returning to its proper position after it has
been depressed by the finger. About midway on each key I place a
small piece of brass or other suitable metal of a longitudinal shape, and
having a slot formed therein, as shewn at d, Figure 2. This piece of
metal carries a hook, shewn at e, Figure 2; such hook may be made
either of solid metal or wire, the metal carriage sliding on a screw f,
Figure 2, fixed in the key. This hook is set to work on a small wheel
having cogs or pins, as shewn in the Drawing at g, Figure 2, and is
suspended and fixed between and in the centre of two other wheels,
shewn at h, h, Figure 1, the three wheels being carried on and revolving
in a metal bracket shewn in the Drawing at i, Figure 2, one of such metal
brackets being placed above and in the centre of each key on a flat iron
bar running through the instrument, as shewn at k, Figure 1, and
secured to such bar in their proper place by means of a screw, as shewn
at l. Figure 2.

page_text: The two outer wheels mentioned above are either made with cogs, as
shewn a g, Figure 2, or they may have pins fixed in their outer circum-
ference which act upon steel teeth shewn at m, Figure 1, formed either
separately or in a comb similar to that of a musical box and fixed to a
second iron or metal bar, shewn at n, Figure 1, in such a position as to
be opposite to such cogs or teeth. When the keys are depressed the
wheels are caused to revolve by means of the hook / gearing into the
cogged circumference of the centre wheel, and when so revolving the
metal teeth coming in contact with the cogs on the wheels emit a
musical sound from which the performer may know whether he is
playing correctly or not. The outer wheels h, h, may act on the teeth
either together or alternately, this depending on the cogs or pins being
set parallel, as shewn at h, h, Figure 1, or between one another. If
thought desirable a small spring may also be placed at the back of the
metal bracket in such a position as to press upon the hinder part of the
centre wheel in order to prevent any back action. This action may be
placed on the further end of the key; in that case the metal comb or
notes must be fastened to the board b, Figure 1, in front of the cogs on
the outer wheel.

page_text: box," substantially in the manner and for the purposes herein-before
set forth and described.
In witness whereof, I, the said William Mead, have hereunto set
my hand and seal, this Nineteenth day of April, in the year of
our Lord One thousand eight hundred and seventy-five.