concave mirror 14, made, preferably, of metal.
Inside of this barrel is an insulated support
15, and upon this support is mounted a crown--
shaped bunch of wires 16 18, having one 5ex-
tremity contracted to support a selenium cell
21, the ends of the crown terminating in
points or antennæ 17 19, bent over radially
and at right angles to the axis of the tube.
The members 10 and C are fully described in
10my prior application referred to.
A Crookes tube 20 and a hollow hermetic-
ally-sealed vacuum-cell 21 of glass, having no
pneumatic communication with each other,
are provided and are placed within the wires
15in such manner that the wires form cages par-
tially surrounding them. The hermetically--
sealed glass cell is of hemispherical shape and
is used for holding a selenium plate, as de-
scribed in my other application. The selenium
20cell is shown here, because it may be used for
telegraphing by flickerings of light in con-
nection with the lamp 20, which has an action
on the selenium plates of the receiving and of
the sending stations.
25The wire 23 is connected with the bunches
of wires 16 and 18 and is also connected with
44 alone for sending and with 46 alone for re-
ceiving. The switch 38 is open in sending,
but closed in receiving. The wires 46 and 25
30and the members 55, 58, 56, and 60 are pro-
vided with suitable resistance. Electrical con-
nections 24 25 are provided for the Crookes
tube in the usual manner. The Crookes tube
is excited in the usual manner by means of a
35sparking apparatus D, which consists of a bat-
tery 30, a Ruhmkorff coil 31, connected thereto
and controlled by a switch 32, a condenser 33,
and a pair of polished knobs 34, and a ground--
wire 35, provided with a switch 36, is used for
40throwing the polished knobs as exciter out of
use when desired and of grounding the wires
as a protection against lightning or against
accidents. The wire 22 is connected with the
wire 37, which is provided with a 45grounding--
switch 38, which must be closed in receiving,
as stated. The switch 32 may sometimes be
substituted for the key 41—that is, when the
secondary connections of coils 43 and 31 co--
act to augment the potential difference 50be-
tween the ends of the secondaries of coil 31.
Then 44 being out of action connects only with
the antennæ through 23, and 24 connects withı
23, 22 with 25, and at its other extremity 22
connects only with 37. 37 connects with 38
55and this with 45 through the ground. In this
case the switch 36 connects with 34, where the
oscillating discharges are produced, and the
conventional interruptions are made by the
key 32. For sending by flickerings of light I
60may use the same arrangement, the switch 36
being in a neutral position, as also the ter-
minals 34. For receiving by flickerings of
light I use the same devices described in my
previous applications referred to.
65A signaling device proper is shown at F and consists of a local battery 39, a switch 40, a Morse key 41, a condenser 42, and a Ruhmkorff coil 43, provided with polished knobs 44 of the usual pattern. From one of these knobs a wire 45 leads to the ground, and another wire,70 46, leads to the crown of wires 16 18. This crown of wires may vary indefinitely in form, and it is used inside of the member C only when working with waves of short length, and then only if it is desired to use the light from75 18 or C.
The coherer is shown at 50. It is connect-
ed with a local battery 51, provided with a
switch 52, the same being adapted to engage
the contacts 53 54. The decoherer is shown80
immediately at the left of the coherer and con-
sists of an electromagnet 55, provided with an
armature 56 of the pattern generally used in
coherers, said armature being adapted to tap
the tube of the coherer 50. The decoherer is85
connected, through wire 57, with the wire 25,
and 57 may connect with 53, 59, and 54 by
means of the switch 52. The contact 58,
which is adapted to engage the armature 56,
is connected with the wire 25'. The wire 5990
is for the purpose of establishing communica-
tion between the battery 51 and the bell 60.
A Morse recording apparatus of the usual pattern and provided with all of the auxiliaries accompanying such apparatus is shown at 6195 and is controlled by a switch 62, connected when closed to contact 54 of switch 52. From the contact 53 a wire 63 leads to the primary 64 of an induction-coil, and from this primary a wire 65 leads to the sonorous receiver 66.100 This receiver is shown more particularly in Fig. 4.
Binding-screws 67 are mounted upon the
frame of the receiver, the screw at the left--
hand side being insulated, as shown. A 105dia-
phragm 68, protected by a disk 70 of insu-
lated material, is mounted directly across the
frame, and over it is a layer of comminuted
carbon 69 in loose form. This carbon is en-
gaged by the carbon button 69ª, upon which110
is mounted an insulating-jacket 70ª. A spring--
tongue 71 normally presses the diaphragm 68
gently against the comminuted carbon, and a
somewhat similar spring 72 presses the button
69ª downward. A funnel-shaped member 73115
is provided with perforations or holes 74, ar-
ranged in concentric rings. These holes or
perforations are for the purpose of emitting
phonetic signals. A diaphragm 75, of iron,
is mounted across the frame, and binding--
screws120 76 and 78 are connected with the mag-
net 77.
The operation of my apparatus when used with short-length reflected waves and with light-waves is as follows:125
The switch 36 is connected to wire 35 and
the switch 32 is closed, as shown in Fig. 1,
thereby exciting the Crookes tube and caus-
ing the same to emit cathode-rays in the usual
manner. The signal-key 41 is now disposed130
