The news & observer. [volume] (Raleigh, N.C.) 1894-current, 1899-05-12
ITS FIELD OF UTILITY
SIGNALLING BETWEEN SHIPS
AND LIGHT HOUSES.
WHAT THE NEW METHOD GREATLY NE D,
Some Power that Shall Prevent Messages Ra-
dating firm the Transmtter. Secrecy
Of Transm' ssion May or Nay
No, be Secured

Washington, May 1.-Gcneral Greedy
today made the first authoritative state
mcnt as to the progress making i'll the
development of wireless telegraphy under
the auspices of the United States Signal
Corps.
The important conclusion is reached
by General Greedy that the wireless sys-
TEN is not likely to supplant the ordinary
method of telegraphic communication.
The results SO far obtained have been
uncertain.
General GreeIys statement is as fol-
loS
''Sincc the announcement OF the tests
in space telcgraphy by Senor Marcolli
two years ago, the subject has been
under consideration by the signal corps
of the army. and recently experiments
have been begun with the object of
thoroughly testing the value of this
means of communication for military ana
other governmental purposes.
.Srecial apparatus has been designed
and constructed for these tests whhch
have already shown sufficient promise
to warrant further and systematic
trials.
I'm view of the great public interest
and in order To facilitate experiments
by other scientists in the United states,
il is deemed proper to put forth this
statement of the operations to the pres
ent time.
"rransmitter-In the experiments
thus far several forms of tranSmitters
for the generation of the HertZian waves
have been used. and much promise has
been realized from the use of IL large
alternating current coil I'M Oil as Il gene
rator instead of the ordinary Rhumkorff
coil employed by MarcCn. This coil is
energized by IA three quarter horse power
rotary transformer furnishing one hun
dred and twenty-five volts ALTERNATING
potential. and this arrangement makes
IL very powerful and efficient source o.:
Hertzan radiation.
"Receiver-The form of receiver used
has been substantially the Brankey ''co-
hered" discovered in 1891. and the sig
mails transmitted are recorded upon re-
ceving tape.
"The transmitter has been mounted
IIon the elevation of the State. War
ard Navy building, utilizing the present
wooden hagpole as the vertical wire
for the transnitter. The receiver WAS
first Faced at the old naval observatory
grounds. about three quarters of Il mile
distant. and later moved to the signal
corps station at Fort Myer. Va.
During the experiments constant COM
munication by heliograph and flag be-
tween the transmitting and receiving
stations has been kept up by the trained
men of the regular signal corps. and this
has greatly facilitated the work of eX-
Eerimenting. Signals. letters and words
have been transmitted and received be-
tween these stations. but the great deh-
cacy and constant adjustment required
in the present receiver have made the
transmission of regular messages as yet
unreliable and uncertain. The presence
of large buildings and meSSes of iron
and metal. necessarily present in cities,
make such places undesirable for carry
ing on experiments of this character.
The distance over which signals may be
Transmitted by a given apparatus is a
function of the height of the vertical
wire used at either end. anl this has
naturally suggested the use of small gus
used for signal and other purposes in
the near future.
That there is IL field for usefulness
for space telegraphy is undoubtad. but
that it will supplant to IA material extent
the use of wire for ordinary commercial
Itelegraphy is not believed Its value
for connection between light houses and
light Ship, and the shore at points where
cables cannot now be permanently main-
tained. will be great.
"For signaling between ships ut sea
and to replace ordinary flag methods
in use between naval vessels. it should
prove invaluable. since no kind of wealth
er. neither fog. darkness. nor storm
avail to affect its use.
"The use of metal retiectolS 10 aug
ment and direct the radiation to particu-
lar points has already met with par
tial success and should he thoroughly i'll
vestigated. At present the radiation pro-
ceeds from the tranSmitter in all direc-
tions and the same message can he re-
ceived at any point within the proper
radius. at which Il receiver is placed.
satisfa ctory directing reflector and n re-
ceiver Of the proper electrical capacity
or. in other words. tuned to the vlbra-
tions of the particular transmitter. would
make Il great advance in space telegra-
ply and do much toward the extension
of it's field of practical usefulness.
While secrecy of transmission is