The Hawaiian star. [volume] (Honolulu [Oahu]) 1893-1912, 1902-04-10
THE EARTH


Been successfully sent.
one of the most interesting inventions
brought to light by the recent develop
ment of the principle of telegraphing
without wires is am apparatus devised .
by ANel Orling, a Swede, and j n. /
Armstrong, am Englishman, and known .
as the Armorl system of wireless tele- /
graphy.
In this system the earth IS the con-
ductor and the currents are of low pO- I
teutial Messages have been sent /.
twenty miles at pressures of eight, and
even of only four, volts. No masts are F..
employed, as in the Marconi system, |
and It is not necessary to elevate the /
transmitting and receiving instru- !
ments.
The key of success of the new sys-
tenn is a novel form of receiver, called .
an electro-capillary relay which is
said to be much more sensitive than
any preceding form of electric receiver. /
1t takes the place of the coherer used
i'm the aerial system of wireless tele-
graphy, and is based upon the infu-
ence of electric currents upon the capil-
larry attraction of mercury
A glass tube, bent in the form of a
siphon and drawn to a fine point is
filled with mercury, the large end of
| the tube being Immersed in vessel
of mercury while the fine point dips
into a basin of calculated water. Just
underneath the point of the tube is
placed one end of a delicate balance
| the other end of which Is close to
Morse machine or other Geographic
instrument. At the top of the bent
tube the positive wire of an electric
| circuit is connected with the mercury,
while the negative wire connects with
/ the acidulated water. When current
! enters the tube containing the mercury,
4 it increases the capillary attraction of
| the latter so that more of the liquid
metal is drawn into the tube and a
minute drop, varying with the strength
| of the current, IS forced from the point
/ of the tube and falls upon tic arm of
! the balance which, being depressed
throws the opposite arm into contact
with the Geographic instrument, thus
completing the circuit.
So delicate has this apparatus proved
that currents too faint to be recorded
| by the most sensitive galvanometers
actuate it successfully.
| In applying the apparatus for tele-
| graphy two iron stakes are driven IN
the ground, about a foot and half
deep and twelve feet apart, and con-
nected respectively to the poles Of the
, instrument, which is furnished with a
| small battery. A Morse key and tele-
phone receiver are attached. At the
| opposite end of the line, which may
be twenty miles away, a similar appar-
atus is set up. The Morse signals are
heard in the telephone with perfect dis
| tinctness, the current passing through
the earth.
This system has recently been applied
to control and guide, in very surpris-
ing manner, the motions of a subma-
rine boat When a submarine boat is
steered by it's own helmsman, the lat
ter is compelled to use more or less un-
satisfactory devices for obtaining views
of the surface of the water above him,
in order to judge what direction should
be taken. But, in this new system Of
steering, the people who occupy the
boat trust themselves entirely to the
guidance of the commander of the yes
sci from which they have been dis
patched. BY simply rotating a Wheel
which sends electric waves into the
water, he can turn the submarine boat
to right or left, and cause it to sink
deeper or rise to the surface. All this
is effected through the influence Of the
electric impulses upon the synchroniz-
ed electric apparatus carried i'm the
submerged boat, which apparatus in
turn, governs the steering-gear with
out any interference by the boats
. crew.
At the same time, and by similar
means, the commander of the warship
can exchange wireless messages with
the men in the submarine boat, in
e. structing them what to do at any par
ticular moment, so that the discharge
of torpedo, for instance can be ac-
curately timed.
Experience is said to have proved
that the electric waves are more per-
fectly conveyed through the water than
through air. The submarine boat may
be driven by any form Of motor that
can actuate a screw, as the electric
control over its movements is inde-
pendent of the motive power.
The transmitting apparatus on the
Warship exercising the control consists
of a small wheel resembling a steer
ing wheel, connected with the Armorl
electric instruments and in communi-
cation with the water through wires
which act like the iron stakes employ
ed when the ArmOrl system is used to
send wireless messages through the
ground. The turning of this wheel
transmits to the water electric oscilIa-
tons with which the apparatus in the
q submarine boat is synchrOnzed. As
the waves reach the boat beneath the
water, the metallic hull of the vessel
acts as a receiving instrument, the bow
and the stern becoming respectively
positive and a negative pole, and the
relay apparatus transmits the impulse
to the steering-gear.
Small torpedoes, resembling the
Whitehead torpedo, are also guided IN
a similar manner the impulses being
T. in this case, transmitted to the pro
y pellers that drive the torpedoes.-Cos'
Z mopolitan Magazine.