POCKET DIGITORIUM
Year: 1884

page_text: PROVISIONAL SPECIFICATION.
I ERNEST WINTER of 14 Bolton Road, St. John's Wood, London N.W. in the
County of Middlesex Teacher of Music do hereby declare the nature of the said
Invention for A POCKET DIGITORIUM to be as follows:-
The object of this invention is to carry a small dumb Piano in the pocket, thus
enabling the possessor to practice finger exercises whilst travelling or otherwise.
The size of the "Pocket Piano" is about 91/2 inches long by 21/, inches wide and
1 inch high. It folds up and being enclosed in a light case may be carried about
like a pocket book, and be used at any time and any where. In appearance it is
like a section of the keyboard of an ordinary Piano, while the action of the keys
themselves is caused by steel springs.

page_text: I, ERNEST WINTER, of 14, Bolton Rd. St. John's Wood, London N.W. in the
county of Middlesex, Teacher of Music do hereby declare the nature of the said
invention for A POCKET DIGITORIUM and in what. manner the same is to be
performed, to be particularly described and ascertained in and by the following
statemen
The present Digitorium differs in principle as well as in details, from any with
which the public are acquainted. The chief distinguishing feature is its small size,
the entire octave measuring only 71/4 inches in length, 2%, in width and 3/4 inch
in height. The white key is 25 inches long and the black one 1½ inch.
This reduction in size is produced to a great extent by a peculiar construction of
the white and black keys, to be described later on.
In outward appearance it resembles a pocket-book, and is therefore extremely
portable. To musicians, and others it ought to be invaluable, enabling them to
practice mechanical exercises at any time and in every place. During the hours
usually lost in travelling, much may thus be acquired, in the way of flexibility and
strength of touch.
The drawings accompanying this are 6 in number viz:
I. The instrument open.
II.
Do.. shut.
III A white and a black key with springs and fittings.
IV Rod with springs attached.*
V Mode of folding a two-octave Pocket Digitorium.
Fig. I. The case of the apparatus is made either of wood or metal, or of a
combination of them, and is covered with leather, or any other suitable material.
Attached to the extreme end of each white key (B) is a strip of leather (L), the
other end of which is fixed to the bottom of the case.
Fig. II When closed, the lid (C) presses down the black keys exactly to the
level of the white ones. The lid is fastened in front by means of a clasp, or
button, and thus prevented from springing open.
Fig. III The top of each white key (B) varies in thickness from the narrow end
at the back part of the box, where it is 1 inch thick, to the front part, thus
allowing of the possibility of the front edge on which the finger is placed being
pressed down to the bottom of the case by means of the strip of leather, which can
be compressed for the time being, and springs back into its place, when the finger
is removed. The keys are hinged to the underneath rod (R) by means of metal
supports (Z). The back part of each black key is even with the white ones, but
at the other end is formed a somewhat slanting projection, raising the key to
the height of an ordinary black key on a Pianoforte. To avoid however, the
necessity for a larger and higher case, the lid pushes down this projection to
the level of the white keys. This projection compels the student to strike the 4
black key in the proper place, and necessitates a good position of the hand.
Fig. IV. Each key rests on a spring (S) which is carried by the metal Rod (R),
which itself is fastened to metal supports (Z) connected with the bottom of the case.
These springs or wires render the action of the keys similar to that of a
Pianoforte. They are made of varying degrees of strength to suit the touch of the
student.
Fig. V. The two-octave Pocket-Digitorium consists of two distinct one-octave
instruments, connected by means of a hinge, and kept in a steady position, when
.

page_text: open by means of a catch on either side. As one end of each case must neces-
sarily be exposed, the lid is provided with a flap (F), which completely closes the
instrument.
Having now particularly described and ascertained the nature of my invention
and in what manner the same is to be performed, I declare that what I claim for
my invention is
In a pocket digitorium, the notes mounted on a rod and pressed up by springs,
the front ends of the white notes (B) being connected by strips of leather to the
case, while the black notes are bevelled in front and have projections (A) by which
they are actuated, all arranged and fitted in a case or folded up substantially as
described and illustrated.