Greene County herald. (Leakesville, Miss.) 1898-current, 1899-07-20
WIRELESS TELEGRAPHY.
WORK OF MARCONPS SYSTEM LITTLE
SHORT OF MIRACULOUS.

IeleBrdpQlnB WIN facility from the
South Foreland lighthouse on the
English coast to Boulogne-sur-Mor in
France without the use of connecting
wires, together with the favorable
reports of commissions appointed by
foreign governments to investigate
the matter Of wireless telegraphy in
general, and the receipt by Mr.. Mar
conf of various government orders for
the manufacture Of his nechanisms,
obviously to be used in warfare, has
attracted the attention Of the world.
To those unyersed in the physical
conceptions of science, it appears
little short of miraculous that by
touching a lever in one place a
sounder may be affected in another
thirty-two miles away without the
use Of any material medium.
Wireless telegraphy, which is today
acknowledged a success for moderate
distances, with the practical certainty
of its application to yer-increasing
distances i'll the future, is due, not so
much to the inventor, Marconi, as to
careful Xperimentation at the hands
of the patient investigators who pre-
coded him. Marconi has discovered
no new law and no new fact. His
work has been merely that of an in
genious mechanician in the careful
application of facts and laws already
well known. The Maconi system of
telegraphy through space depends
primarily on the work of Hertz, who
proved some ten years ago in series
of researches, which are now classic,
the existence Of electrical wave in
free space, the identity Of electricity
with light, and who made it a tenet
of modern science that the universe
is not a universe of emptiness, but
'plenum. His work, as well as the
wireless telegraphy based on it, is ex-
plicable only on the assumption that
between the particles of all material
bodies, and throughout all space to
the furthest star to be seen with the
mightiest telescope, there exists me-
dium whose most marked characteris-
ties are tenuitv and almost infinite
elasticity. This medium is the ether
of the physicist. Wave motions may
be set up in this medium with ease,
their effect depending solely upon
their length. The X-rays of Roentgen
form probably the shortest of the
series; and, in their order of length,
come the actinic waves, which affect the
camera light waves, waves of radiant
heat, then q vast unexpiored space,
and, finally, the long, electrical waves
which affect the Marconi receiver.
DR.. Hertz succeeded in setting up
these electrical waves by means of
rapidly oscillating electric spark from
an induction coil. They vary in length
from a few inches to many feet, travel
at the rate of 16G, 600 miles a second,
and vary in intensity inyersely as the
square of the distance. That is at
twice the distance they are one-fourth
as intense, at five times the distance
one-twenty-ffth as intense, aud SO on,
rapidly decreasing as the distance in
,reases.
The Marconi transmitter is simply
a Hertzian oscillator for the pIopaga-
lion of these waves, consisting OF a
medium sized induction coil with the
spark passing between two perfect
spheres of polished brass half i'm
nersed in oil.
The electrical waves in ether, caused
by this rapidly intermittent spark,
start ont with a frequency OF some
two billion a second in series Of con-
centric, ever widening spheres of un-
dulation, travelling with the speed Of
light in all directions and straight
through the ordinary forms of matter
with but little opposition. Into the
primary circuit OF the induction coil
is introduced common Geographic
circuit breaker, by which the sparks
may be made to come in the order of
telegraphic signals.
The Marconi receiver depends for
its efficiency on the discovery Of Bran
ly, that when these electrical waves
strike pinch of metallic filing such
filings become conductor. The CO.
herer, the essential part of the Mar
conf receiver, consists of a small glass
vacuum tube, into each end of which
runs brass rod tipped with silver.
The ends of these rods are separated
by a distance of about ne-sixteenth
of an inch, and into this tiny space is
placed pinch of metallic filings, pre-
ferably nickel, with trace of silver.
The coherer is in circuit with one bat
terry cell and a sensitive relay, the
current of the cell being interrupted
by the filings. This relay is, in turn,
in circuit with larger local battery
and a telegraphic sounder. From
each end of the coherer there runs a
copper wire, one into the earth to in
tercept the waves travelling through
the ground, and the other high up in
the air to catch the waves that travel
there. These waves run along the
wires and across the pinch of filings,
which then become conductor When
the filings become in this way a con-
ductor the current from the single
cell is allowed to travel through the
relay and the relay in turn lets loose
the local circuit, which makes the
soundor click.
The matter is somewhat complicat-