tube C, with a mouthpiece c. When the ap-
paratus is to be used, the user speaks accord-
ing to a predetermined code or in such other
manner as may be agreed upon into the 5mouth--
piece c. The sonorous waves propagated
through the tube and passing through the
central aperture of the cap A² impinge upon
the diaphragm a, producing a corresponding
vibration thereof, whereby if the adjustments
10have been correctly made a very rapid serïes
of makes and breaks or successive contacts
will take place between the diaphragm and
the tip b², corresponding in frequency to the
waves originating them. These makes and
15breaks produce impulses or variations of cur-
rent in the primary circuit 1 2, the connec-
tions of the circuit being clearly shown in
Figs. 3 and 4. In Fig. 3 the terminal wire 2
from the local battery m is connected to the
20spindle B at its lower end or head, while the
primary wire 1 passes direct to the winding
and thence ton connection with the diaphragm.
In Fig. 4 the primary wire 1 passes through
the coil to the diaphragm, and wire 2 is 25con-
nected to the tipb² of the spindle. Obviously
in either case the effect of makes and breaks
will be to cause pulsations of current in the
primary winding corresponding very closely
to the tones of the speech or sounds which
30caused them. It is of course impossible to
get any adjustment short of a perfect contact
that will give all of the overtones and will
render the articulation perfect; but, on the
other hand, in order to obtain the discharge
35effects, to which I shall presently allude, I
find it is better to have positive breaks than
mere changes in resistance in the circuit. It
goes without saying that I can adjust the con-
tacts so as to produce constant contacts and
40variable pressure, which are the requisites for
perfect microphonic working; but for practi-
cal purposes I find it is better to produce the
impulses in the manner I have described.
Referring now to Fig. 5, I will describe the
45connections of my apparatus to produce an
operative system. As Fig. 6 shows the same
parts in more detail reference may also be had
thereto from the detail connections. In these
figures F is a Ruhmkorff or other high-power
50induction-coil adjusted to produce a spark of
some length- say from one-quarter inch up-
ward. The primary winding f of this coil is
connected in a circuit 15 16, containing the
main battery M and the phonetic interrupter
55A. The secondary winding of the coil F.
which is marked f’, is connected by wires 7
and 8 to the terminals 21 and 20 for the radiat-
ing bodies or wires, which may be the usual or
any special desired form of aerial conductor,
60with or without earth on one side. Adapted
to be bridged across this circuit 7 8 by the clos-
ing of the switch S’ on its contact s’ is a pair
of sparking terminals 12, the bridge-wires
being marked 9 10. A condenser G’ of suit-
able capacity is also connected across the 65sec-
ondary circuit by means of wires 13 and 14.
The primary circuit 15 16. passes from the
Ruhmkorff coil to the primary terminals of
the induction coil D in the phonetic inter-
rupter. The secondary winding d’ is 70connect-
ed in a local circuit 19, which contains a tele-
phone-receiver T. and the primary circuit con-
tains a lamp E, which may serve for both send-
ing and receiving messages. A condenser G
of suitable capacity is also bridged across the75
primary circuit.
The operation of the system thus described
is as follows: For transmitting Hertz waves
corresponding to sonorous vibrations the
switch S’ is closed, the switch S is opened, and80
the operator proceeds to produce sounds in
the desired manner into the mouthpiece e of
the phonetic interrupter. A succession of im-
pulses is thus produced in the primary circuit
of the coil F, whose effect is increased by the85
presence of the condenser G, which takes up
the extra current, assists in the rapid demag-
netization of the core of the induction-coil,
and also prevents sparking between the dia-
phragm and the tip-terminal. These impulses90
in the primary, which are very rapid, with
proper adjustment reaching between five hun-
dred and nine hundred per second, produce
very high potential impulses in the secondary.
To produce oscillations of light by means of95
the interrupter in the sending-station, I use
the natural human voice, preferably because
the flickerings produced corresponding in
form and frequency to the initial sounds and
being property retranslated through the100
agency of suitable apparatus at the receiving--
station enable the original sounds to be recog-
nized more or less perfectly, and while many
words or tones can be recognized for their
intrinsic value, as well as for any arbitrary105
code value that may be assigned to them apart
from this, a sufficient number of distinctive
words can be selected to make a complete and
very efficient code.
Obviously as a substitute for the human110
voice other sources of sonorous vibrations
may be employed. Thus to produce elec-
trical oscillations by means of the same in-
terrupter I may use at the sending-station a
source of sound consisting of a musical in-
strument115 similar to a small organ, having a
set of reeds or pipes with controlling devices
and one or more acoustic tubes connected to
the mouthpiece of the interrupter-tube. The
diaphragm of the interrupter being thus120
strongly vibrated causes oscillations of light
or electricity which may be received after
transmission by means of any suitable sensi-
tive device. In addition to this method of
transmitting by means of electric or luminous125
waves, as I have said, certain of the features
