The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1902-01-16
WIRELESS TELEGRAPHY.

- farthest and with least resistance IL
those directions where it finds the bes
- conductors for it. Some substances ar
better conductors than others. Glass
and rubber are non-conductors, SOCIAL
ed. as you may see by looking at tn'
= rubber covering of wires on the stree
lie car system, or the glass insulators on
y telegraph pole. Metals. such as iron
| steel and copper, are first-class con
ductors, and that is why wire is USED
. for telegraph and telephone and cleo
= trio light purposes. Water and the
= earth are conductors of electricity. and
SO Is the atmosphere. When Benjamin
Franklin, by his famous experiment
with the kite, proved that lightning is
I nothing but electricity, he also proved
n that the atmosphere is a conductor, for
g q bolt of lightning may travel many
miles before striking the earth Mere
space. finally, is a conductor of cleo
tricity. as you can prove by passing a
, current through a vacuum.
II AS soon as one comprehends that
electrical waves can move in space
without the conventional wire conduc-
tors. IL is evident that the question OF
teIeeraphy with wires or without wires
, must depend largely upon the trans
hitting and receiving apparatus wires
hitherto have been used because, with
| the apparatus available for sending
and receiving electric currents, they
/ have afforded the best results; indeed.
for considerable distances they afford
ed the only results that could be de-
| pended upon. Even with wire as a con-
] ductor, far more delicate receiving in
| struments have to be used on an At
| lantic cable than on a circuit between
| Springfield and Buffalo. Now Marconi
| is by no means the first one to expert
ment with wireless biography. Many
| men have been working at the prob
| lem for years. And essentially their
| problem has been to perfect apparatus
at one end which would generate cleo
trio waves strong enough to travel long
distances, with mere space as the con-
ductor, and apparatus at the other end
sensitive enough to receive and record
those waves.
The transmitting and receiving ap
paratus thus far developed is compli- !
Gated, and one needs some technical |
knowledge to understand 1t. You will !
reach much about Hertzian waves In
this connection. HertZian waves are
waves of electricity. Hertz was a Ger
man professor, who died in 1894. He
was the first man to prove by expert
ment that whenever in any circuit
electromagnetic changes are brought
about, as when an induction coil is in
action. the disturbances are transmit
ted in all directions, bringing about
similar changes in neighboring conduc-
tors. His great work was to show that
these disturbances are transmitted by
means of vibrations OF the luminifer
Gus ether (Which is assumed by physic-
lists to fill all space), and also to show
the character, and measure the velocity !
those "
rapher, therefore, first generates Hertz
ian waves of electricity into space.
Cen Greedy, head of the United States
army signal service, in describing the
transmitter used by the signal corps
in experiments, over two years ago, re-
ported that he used a coil in oil, EN- 4
ergized by q three-quarter horse-pow
er rotary transformer, furnishing 125 I
volts alternating potential, an ar
rangement making "a very powerful
and efficient source of Hertzian radia-
ton" Marconi used at that time a
Ruhmkorff coil. According to present
the Hertzian waves are
transmitted by the generator through
a wire to the top of high pole, and
that is where the jumping-off place is.
From the top of the pole, the Hertz 4
ian waves are radiated off into space.
About one-ffth of a horsepower is
necessary to send them sixty miles at
sea, and a 1000-rnile range, it is said.
ought not to require much more than
3k horsepower. provided the energy
can be utilized. To send the waves {
across the Atlantic, the problem of L
transmission is a question of propell- (
ing force. The Hertzian waves follow /
the curvature of the earth. I
Marconi improved the receiving ap-
paratus by discovering, or inventing. Z
what is known as the "decoherer 4
which consists of a ball working on 9
an arm attached to the armature of an
electro magnet in the circuit of the
"coherer,' or receiver. But that aside
Enough has been said to show that this
apparatus, both sending and receiving,
is highly technical, and difficult to be
in detail by one who is no
or has never witnessed ex-
periments in wireless telegraphy. Suf-
flee it to say that when Marconi, the
other day, in Newfoundland, received
the wireless message from the coast of
England, he flew a kite in the air, and
from the kite was suspended a wire
connecting with his receiving instru-
ment- The Hertzian waves had passed
over the ocean from the tall pole on
the England coast, and had struck the
wire on the kite in Newfoundland, The
electric vibrations were thus transmit
ted to Marconi's delicately adjusted re-
ceiver. and read by him exactly as :
they mad been sent across 1900 miles of :
ocean.
Marconi's system uses the atnnos-
phere as conductor. Nicola Tesla, il
is understood, is experimenting on a
system that uses the earth as conduc-
tor. 1t seems safe to predict that sci
ence will completely master the field
II wireless communication through
ong distances before many years have
passed. Evidently the experimenters :
are only in the infancy OF the art. I
Buddhists in Japan.