AN ARRANGEMENT OF SEMI- AUTOMATIC APPARATUS FOR TRANSMITTING TELEGRAPHIC MESSAGES WITH THE MORSE SYSTEM
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Henry Gardner at the Office of the
Commissioners of Patents on the 27th July 1877. A communication from
abroad by M. le Comte Emile Siccardi, of Turin, Italy.
$
HENRY GARDNER, of the Firm of Robertson, Brooman, and Company, of 166, .
Fleet Street, in the City of London, Patent Agents. 'AN ARRANGEMENT OF SEMI-
AUTOMATIC APPARATUS FOR TRANSMITTING TELEGRAPHIC MESSAGES WITH THE
MORSE SYSTEM." A communication from abroad by M. le Comte Emile Siccardi,
of Turin, Italy.
It is well known that in the Morse system signals are formed by the combination
of points or dots, and dashes, lines, or strokes. The communicator for these signals
consists of an oscillatory lever, upon the head of which the operator leans or presses
to close the circuit and pass the current into the receiver. The time during which
the lever is kept lowered is short, or relatively long, according as it is desired to
produce points or lines at the opposite station.
This operation demands of the workman to whom it is entrusted great skill and
practice from the marvellous rapidity with which he has to work, combined with
certainty of results. These conditions are not always attained, and the result is
confused, or illegible despatches. The object of this Invention is to do away with
these inconveniences.
The Invention consists essentially in the employment of two contiguous finger
boards or keys, one for points or dots, and the other for dashes, strokes, or lines.
These finger boards are for this purpose joined by two vertical rods to a double-
branched interruptor lever, the lowering of which must determine the contact which
closes the circuit. The ends of the two branches upon which the rods of the keys
act are furnished with distinct appendages so combined that the oscillation of the
interruptor lever is effected differently, according as it is desired, to produce a short or
a long contact. By this arrangement the operator has not to trouble himself about
the duration of the contact to be furnished; it is sufficient for him to lower one or
the other of the keys, according as he wishes to send lines or points. Such is the
principle of the semi-automatic communicator, the arrangement, action, and
advantages of which will be fully understood by reference to the annexed
Drawings.

page_text: The apparatus is represented in side elevation, Figure 1, and in plan, Figure 2.
A is a wooden base or pedestal supporting the column B, also of wood, upon which
are fixed the three metallic supports, C, D, E, communicating with the three bars,
1, 2, 3, by conducting wires which pass through the interior of the column B.
Upon the same pedestal is also fixed the bronze support F; upon this latter are
movable, upon a horizontal axis, the two finger boards or keys, of strong wood
G, G', one only of which is represented in the side view, Figure 1. These two
keys are surmounted by two vertical metallic rods H, H', which carry at th eupper
ends two bronze wheels I, I', moveable round a steel axis.
L is a piece screwed in the column B, by means of which can be fastened and
stretched, more or less, the two helical springs M, M', destined to bring back the
two keys G, G¹, to their original position.
N is a metallic lever screwing into two branches b, b', and moveable upon the
support C. At the front end of the branch ba steel triangle t is fixed; the branch
6' supports at the same point a steel ratchet moveable upon the carriage x, which
may be caused to advance or recede at will.
S is a conducting wire having for object to establish direct communication between
the lever N and the support D, which is itself in communication by means of the
wire passing through the interior of the column B with the bar No. 1, which
represents the line.
The lever N carries at its extremity O a platinum plate, and at the point O¹¹ a
point or centre, also of platinum, in order to ensure the contacts which must be
established between the lever N and alternately between the screw U and the little
lever k.
D is a metallic support upon which is fixed the screw U, having by an interior
wire communication with the bar No. 2, which establishes contact with the local
receiver.
k is a little metallic lever kept constantly raised by the action of a bossage fixed
under it. This little lever is in communication with the bar No. 3, which repre-
sents the pile.
Action of the Apparatus.-The alphabet being composed of lines and dots at a
distance established between them; when it is desired to print a line the key
opposite the branch bis lowered; this being naturally pressed upon the triangle t,
forces the lever N by this movement to leave the screw t, t, with which it is in
constant contact while in a state of repose, and to encounter the little lever k with
which it establishes a strong contact during the entire course of the key itself.
But as it is known that it is only the duration of the contact which can form a
dash, it will be easily understood that it would be impossible in this manner, by
going ever so quickly, to print a point instead of a dash.
Scarcely has the finger of the operator left the key before the latter, brought
back to its original position by the helical spring M', again puts itself in contact
with the screw n, thus re-establishing the communication of the line with the
local receiver.
When it is desired to print a dot the key opposite the branch b' is lowered; this
in its descent meets the ratchet x, which is only moveable in a direction opposite
to this course, the return movement establishing thus a very rapid contact between
the lever N and the little lever k. By removing the finger the key returns, but by
reason of the movability of the ratchet x it only rises in its return, leaving thus
immovable the lever N, which had already re-established its contact with the screw
u immediately after its downward passage upon the ratchet x.
As will be easily understood any one adopting this new communicator will derive
the following very important advantages
1. The impossibility of faults arising from the formation of the signs, since by
this mechanical system the dots and dashes are invariable, while with the present
arrangement the formation of the signs is entirely dependent upon the attention
and skill of the operator.
2. The work being with this new arrangement necessarily divided between the

page_text: two keys, it consequently happens that the required distances between the signs
which form a letter (and without which it would be impossible to read the message)
are established and perfectly regular after very short practice.
3. The time necesary for the study of this apparatus being much shorter than
for that of the present single key, it can also be adapted with great advantage for
the service of railways, where the operators are generally men who by reason of
performing several kinds of work cannot of necessity be skilful telegraph officials.
The advantage will be felt both by the new employés who have to be taught and
by those who have had long experience in telegraphy.
4. The speed of the transmission cannot but be remarkably increased, because
having the dots determined with reference to the dashes, these latter may be much
shorter without in the least injuring the clearness of the message, and also because
the time at present employed to repeat defective messages will be saved.
5. Lastly, the working of the new key is much less fatiguing than the present
Morse communicator, since the arm of the operator has no longer any movement
to make nor force to exert.
By an arrangement about to be described, and the Drawings of which are repre-
sented, the present communicator may furnish in an unfailing manner the discharge
direct to the earth after each line current. It can therefore be applied with great
advantage to long aerial lines, to ground cables, and underground cables, and to the
submarine cables, which not having a great length, permit the employment of
ordinary Morse machines.
It will be seen by the following description that this communicator might also
render important services upon long submarine cables where the Morse alphabet is
only composed of dots, either for the use of the galvanometer mirror, or for that of
the siphon recorder of Mr. Thomson.
The following is a description of the parts relating to the direct discharge of the
line to the earth for long aerial lines, and for short cables.
The lever N, which indicates the line as previously stated (1 & 2), carries
at the side of branch b¹, destined to print the dash, a platinum rod m, movable
upon a spring, and forming part of the metallic piece d, which is itself isolated
from the lever N, and giving communication with the earth by means of the
spring S. Now as the rod t carries fixed to its upper end a cylinder r', half
metal and half glass (Figure 6), each time the "dash" key is lowered the cylinder
encounters the metallic piece m on its isolating side, passes over it, and returning,
encounters it again, but on its metallic side; and before the contact is re-established
with the receiver, it is evident that the discharge of the current will take place
direct to earth since the rod t forms part of the line.
The same result may be obtained, but by a different arrangement, for the key
which prints the dots. The branch b of the lever N carries screwed to its front end
an elastic plate of steel u, Figure 5. This plate is also isolated from the lever N,
but in communication with the earth by the helical spring S. But as the "dash"
key carries also screwed to its upper end a metallic piece r, Figure 6, this establishes
a contact of the line with the earth as soon as the point has been printed, and
before contact with the receiver can be re-established. It is evident that the same
arrangement may serve for the discharge of submarine cables to the earth, and one
could even (either for the discharge of submarine cables or for long aerial lines)
arrange that each emission of the current should take place between two discharges
to the earth. For this purpose it would be sufficient to arrange the communications
with this apparatus in such manner that the discharges to the earth should take
place by the contact of the lever N with the little lever k at the point o¹ (see
Figure 1), and the sending of the currents upon the line by arranging below the
two keys G, G¹, (Figure 2), metallic pieces in such manner that this sending of
currents takes place by lowering one key or the other, and directly by themselves,
which will result very easily from the manner in which the two keys are arranged.
These two keys in the state of repose will establish contact with the receiver.

page_text: In order to have the discharge of the line direct, to the earth before and after each
sign sent, it will be sufficient to substitute for the movable ratchetex, Figure 1, and
the piece or inclined plane which must print the dash, two stops fixed in such
manner that the two keys will, in their going and coming movements, be compelled
to pass over them, establishing contact between the lever N and the little lever k 5
(Fig. 1), that is to say, between the line and the earth.