IMPROVEMENTS IN APPARATUS FOR RECORDING MUSICAL NOTES
Year: 1881

page_text: LETTERS PATENT to James Wallis, of 135, Euston Road, in the County of
Middlesex, for an Invention of
" IMPROVEMENTS IN APPARATUS FOR
RECORDING MUSICAL NOTES." A communication from abroad by Joseph
Föhr, of Stuttgart, Germany.
PROVISIONAL SPECIFICATION left by the said James Wallis at the Office
of the Commissioners of Patents on the 28th December 1881.
JAMES WALLIS of 135 Euston Road, in the County of Middlesex. "IMPROVE-
MENTS IN APPARATUS FOR RECORDING MUSICAL NOTES." A communication
from abroad by Joseph Föhr of Stuttgart, Germany.
This Invention relates to apparatus for automatically recording the notes played
on pianos or similar instruments, so as to enable the player to reproduce the same
tune any time after it has been once played.
The apparatus, which may be called an electro-chemical piano-telegraph, consists
of the following principal parts viz.: The key board mechanism, the ruling and
writing apparatus with its driving mechanism, a contact apparatus for marking
intervals of time, an apparatus for preparing the strip of paper with a solution of
chemicals, and a galvanic battery.
The key board mechanism is placed over the rear portion of the keys and
consists chiefly of a series of vertical rods or pins one for every key and following
the motion of the latter, thereby closing an electric circuit whenever a key is
depressed. Every pin has at its lower end a disc resting on the corresponding key,
and at its upper end a conical head, which comes in contact with a metallic contact
plate when the key is depressed, the downward motion being effected by means of
a spiral spring. For guiding the contact pins and connecting the same with a
battery, a wooden rail runs along the key board, provided with as many vertical
perforations as there are contact pins and having at top and bottom a metallic
strip connected with one pole of a galvanic battery. From every contact plate of
which there is one for every contact pin, & conducting wire leads to the left hand
extremity of the key board, where the wires are united to form one cable which
n

page_text: leads to the writing apparatus. In the latter the wires pass first through an
insulating bar to the opposite side of which they are secured by means of screws.
A second insulating bar is laid along the first one and provided with conical
perforations the axes of which are in straight lines with the said fixing screws.
Each of the said conical perforations contains a spiral spring which presses on the
head of the screw. In order to diminish the number of conducting wires the
corresponding contact plates of the first and second octave, as well as those of the
last and last but one octave are respectively connected with each other by a wire.
The distance of the contact plates from the key board may be regulated by means
The ruling and writing apparatus is placed at the left side of the
piano and constructed as follows: The travelling sheet of paper passes over a
roller opposite a series of marking pencils and in contact with a second roller
provided with a series of ringshaped projections which come in contact with the
paper thereby producing the necessary lines while a third roller is placed over the
second one and provides the latter with colour.
of set screws.
The rollers are set in motion by a clockwork, the speed of which can be
regulated.
If the lines are produced by an electric current acting on the chemically prepared
paper the third or coloring roller may be omitted. The full lines and the dotted
lines appear in two different colours. The series of marking pencils is composed
of iron or steelpins corresponding to the lower (white) keys, and of copper or brass
pins corresponding to the upper (black) keys. The other end of the marking
pencils rests on the narrow upper face of vertical metal plates, insulated against
each other, but connected with two shafts. From the lower end of every metal
plate a fine insulated conducting-wire-leads-to-and-through-a-bar and is attached
to the opposite face of the latter by a screw, the head of which projects into one
of the conical perforations of the above described insulating bar, and is thereby
connected with the corresponding conducting wire from the keyboard mechanism.
The guide roller against which the marking pencils are pressed is connected with
the negative pole of the battery.
The intervals of time are marked at the upper and lower margin of the strip of
paper, by means of a special contact mechanism worked by a pedal which serves
to open and close an electric circuit. Between the paper roller from which the
travelling paper is unwound and the marking apparatus a glass or porcelain vessel
is inserted, which contains a sponge impregnated with a chemical solution. Above
the sponge is placed a roller which serves to press the paper against the sponge, and
is supported by movable bearings, so that it can be approached to or removed from
the sponge, the latter when the writing apparatus is out of action. The source
of electricity is preferably a Leclanché battery placed under the marking
apparatus.
In playing the instrument every key which is depressed produces on the
travelling paper a line, the length of which corresponds to the length during which
the key is held down, thereby reproducing the notes which have been played in
such a manner that they can be subsequently transcribed into ordinary writing by
shifting along the strip a short plate on which are marked the names of the notes
which correspond to the different lines.

page_text: This apparatus is illustrated by the accompanying Drawings, and composed of
The keyboard-mechanism is placed over the keys upon the outer visible portion
of the piano and constructed as follows:-
To one side of a Liron 1 (Fig. 3) is fixed a wooden rod 2 projecting over
the bottom flange of the iron. Over and under this wooden rod are situated
metallic rails 3 and 4 which, together with the wooden bar, are perforated over
every key a, so as to form a series of vertical holes. (Instead of the wooden bar
and metallic rails a ☐ iron bar may be used). Through every one of the said
vertical perforations passes a metallic pin 5 carrying at its lower end a round
wooden disc 6 lined with a disc of thin felt 7, which rests on the key a of the
piano.
The upper end of the pin is split and provided with a screw-thread into which
enters a conical metallic head S, with its point turned downward. Immediately
under these heads the pins pass through round openings in horizontal metal-
plates 9, which are screwed on a second wooden bar 10 situated at the top of the
1 iron and projecting backward. Between the wooden disc 6 and the lower
metallic rail 4 the metallic pins are surrounded by helical springs 11, which tend
to expand so as to push the pin downward and to draw the conical heads into the
apertures of the metallic plates, following the motion of the piano-keys. Between
the upper wooden bar 10 and the bottom-flange of the 1 iron is left a hollow space
12 turned towards the back of the piano.
While the two rails 3 and 4 (or the ☐ iron) at the front of the key mechanism,
and consequently also the metallic pins and bends passing through these rails (or
the iron) are connected with the positive pole of the galvanic battery b, an
insulated conducting wire 13 leads froin every horizontal metal plate 9 into the
hollow 12 through which all conducting wires are led to the left hand extremity
of the key-board, where these wires are united into a bundle 14 of 50 to 75
centimetres length (Figs. 1 and 2). The individual wires of this bundle pass then
separately through a short insulating bar 15 and are fixed at its opposite side to
small screws with heads 16. With this insulating bar is connected a second
horizontal bar 17 of the same length and provided with perforations in a line
with the screw heads of the first bar. These perforations contain helical springs 18
against which press the screw heads when the two bars are united. On the
opposite or free side of the second bar 17 the diameter of the perforations is

page_text: somewhat smaller than on the side turned towards the key-board, in order to
prevent the springs from falling out.
For regulating the distance of the key-board mechanism from the keys and the
distance of the contact-heads from the contact-plates, two vertical set screws 19 are
provided at each end of the key-board.
In order to reduce the number of conducting wires leading from the key-board
mechanism to the writing apparatus, the corresponding (equally-nained) contact
plates of the first and second octave as well as those of the last and last but one
octave are respectively coupled together by a conducting wire.
II. WRITING AND RULING APPARATUS. (FIGS. 1 AND 2).
The writing and ruling apparatus mounted on a separate table c at the left of
the piano, is constructed as follows:-
With a clock-work or driving mechanism d (Fig. 2) whose speed can be regulated,
is connected a roller 20 (about 12.5 centimetres long and 3 centimetres diameter)
turning from the left to the right and carrying a counter-roller 21. This counter
roller is provided with fine parallel projections 22 forming partly continuous and
partly broken lines and corresponding to the system of notes. These lines produce
impressions on the endless strip of paper passing between the two rollers. The
raised portions of this ruling roller are coloured by a cloth-roller 23 which is
situated above it and impregnated with colouring matter. The continuous
(ordinary) note-lines appear in black, the broken (auxiliary) lines in light-blue colour.
The cloth-roller 23 may be omitted, if the lines are produced by electric.currents-
-acting-on-the-chemically prepared paper. In this case the ruling roller must have
insulated axle bearings and be connected with the positive pole of the battery by a
special conduit.
On the roller 20 rest marking pencils 24 (61 in number) placed parallel with
each other about 1 millimetres apart. These pencils consist of brass plates
armed at the thin end with platinum pins. The pins corresponding to the (white)
lower keys are somewhat flat-pointed, while the pins corresponding to the (black)
upper keys are almost sharp-pointed, so that the signs for the full notes appear as
broad lines, while the signs for the half notes appear as fine lines.
The thick end of each marking pencil rests with a semicylindrical groove on the
correspondingly shaped top side of a small metal plate 25 placed in a row with its
neighbours and insulated from the same. A rod of insulating material 20 placed
over the marking pencil serves to maintain a constant connection between the
marking pencil and its metallic base. Vertically over this rod is placed another
rod 27 to which are secured curved springs 28 of metal wire, which lie in recesses
of a guide-bar serving also to fix the position of the marking pencils towards the
ruling roller, and press the marking pencils down upon the paper. The rod holding
the press springs has at its side a horizontal arm 29 acted upon by a vertical screw
spindle by which the pressure of the marking pencils upon the paper can be
regulated at will.
From the lower end of every metal plate an insulated fine conducting
wire 30 leads to a bar 31, on the outer side of which (the side turned towards
the piano) the conducting wires are fixed by small metallic screws with pro-
jecting heads 32. These heads fit into the apertures of the insulating bar 17 at
the end of the conducting wires of the key-board mechanism, which apertures are
filled with helical springs as already described. The circuit or electric connection
is established by uniting the insulating bar 17 belonging to the key board
mechanism with the rod 31 belonging to the marking apparatus by means of two
hooks 33 (or by means of bolts and nuts). The roller 20 on which rest the
marking pencils, is connected with the negative pole 34 of the battery.
The clock-work or driving mechanisin which moves the driving roller 20 may
be driven in any suitable and known way by weights, springs, electricity or other
power.

page_text: III. CONTACT APPARATUS FOR MARKING INTERVALS OF TIME.
A special contact-apparatus (Fig. 4) placed under the piano, consists of a desk
shaped wooden piece 35 with a metallic contact-plate and a metallic spring blade 36.
When acted upon by the feet, it serves to mark the intervals of time on the upper
and lower border of the paper band by means of points produced by two additional
marking pencils 37 provided for this purpose (also by electro-chemical action.)
IV. APPLIANCE FOR PREPARING THE PAPER-BAND WITH THE CHEMICAL SOLUTION
DURING THE OPERATION OF THE APPARATUS.
Between the roll of paper from which the travelling band is drawn, and the
writing and ruling apparatus, is fixed a rectangular trough 3S of glass or porcelain.
This trough serves as a receptacle for a sponge 39 saturated with a chemical solution
(ferrocyanide of potassium). Over the sponge is placed a roller 40 which presses
with its weight on the sponge, while in front of the glass trough (in the direction
of the motion of the paper) is secured a small roller 41 projecting over the surface
of the sponge.
ceases.
When the apparatus is at rest, the loading-roller 40 may be removed from the
sponge by means of a lever 42. A few revolutions of the ruling roller suffice for
lifting the paper-band away from the sponge, after which the reception of colour
This arrangement enables one to supply dry paper to the writing and
ruling apparatus when at rest. If no sponge is used, the paper-band is conducted
over a wooden roller surrounded with fine woven tissue, which roller dips into the
chemical solution. A roller lying on the paper serves to ensure its constant contact
with the colouring roller.
V. BATTERY.
A galvanic battery (preferably Leclanche's system) is placed in a box under the
table which supports the writing and ruling apparatus.
The apparatus operates as follows:-
From the positive pole of the battery a conducting wire leads to the two metal-
rails 3 and 4 of the key-board mechanisin (or to the ☐ iron) and by means of these
rails to the contact pins 5 which rest vertically on the piano-keys.
If the keys are depressed the pins descend likewise so as to cause their conical
heads 8 to fall into the apertures of the metal-plates 9, against which they are
pressed by the action of the helical springs 11. By this contact the clectric current
finds its way through the conducting wires 13 connected with the metal plates 9 to
the helical springs 18 which establish the connection between the key-board
mechanism and the writing apparatus, from there it flows to the horizontal bar
which forms a pivot for the marking pencils, subsequently through the marking
pencils 24, the moist paper and the driving roller 20 to the negative pole 34 of the
battery. Those marking pencils which close a circuit in consequence of the
depression of their piano-key produce blue marks on the paper. According to the
length of time during which the keys are depressed, the marks produced are
shorter or longer, thus indicating the duration of the respective notes.
To facilitate the transcription of the recorded signs-that is the shorter or
longer lines produced by the marking pencils-into ordinary writing or music sheets,
a pattern sheet g (Fig. 5) is mounted in a desk shaped wooden frame or plate, and
the record-sheet slowly drawn away under the pattern-sheet.

page_text: 2. The contact device 35, 36, and 37 for marking intervals of time by means of
a pedal.
3. The apparatus for preparing the paper-band or record-sheet.
The whole substantially as described and illustrated by the Drawings.
In witness whereof I the said James Wallis have hereunto set my hand and i
seal this Twenty seventh day of June A. D. 1882.
JAMES WALLIS. (L.S.)