The herald., 1898-10-31
EXPERT ELECTRICIANS
USE ALTERNATIVE CURRENT
IN TELEoRAPHY
4 REVOLUTION IS PROMISED
In Methods Now in Use Over Ocean
Cables-Working Capacity to
Be Increased
Associated Press Special Wire.

WASHINGTON, Oct. 30.--One point In
the annual report of General Greedy has es
capped public attention owing to its disasso
citation with the late war. 1t relates to the
discoveries of two young physicists, Prot. A
Y. CrehOre and Lieutenant Colonel George
y. Squier, volunteer signal officers, who
have lately pursued, under the direction OF
scientific Investigations that promise to work
a revolution in the methods of ocean tel
egraphy.
General Greedy expresses his belief that
these discoveries and inventions have as
sumed such form and phase as to be OF the
greatest value to the commercial world.
The discovery outlines the true scientile
wave system. The first experiments were
made at the artillery school, Fort Monroe,
Virginia, and We're discussed Theoretically
in 1897, under the title of Interchangeable,
new method of rapidly transmitting in,
formation by the alternating current. The
next step was the testing of this system on
long telegraph line, and for this purpose
Prof. Crehore and Colonel Squier visited
England, where they were afforded every
facility for experimental work over the gov
ernment telegraph lines, through the cour-
tesy of the postmaster general and the dis
tinguished electrician, Chief Engineer
Preece.
The experiments, the report sets forth,
proved conclusively the superiority of a
the typical form of which is a simple Sine
wave, as compared with the system now ex'
clusively used throughout the world in code
telegraphy Under the Sine wave system
words were sent and received over a line
HOO miles long at a rate OF over 1000 words
per minute.
Under this new system the speed of the
Whaafstppe commercial recaivpr waS IN
creased as much as threefold when operated
under identically the system Of the old code
telegraphy The superiority of the Sine
wave having been decided by experimental
apparatus, the next step is to construct
transmitters for actual commercial condi.
tions. Two special apparatuses were de-
vised, one for operating land lines and the
other for the transmission of messages over
long cables. The cable transmitter was
completed and land instruments well adj
vanced when the late war interrupted prog
ress, which has only lately been renewed by
direction of General Greely.
The first practical tests of the cable trans
courtesy of George Clapperton and other
officials of the Commercial Cable company
of New York. The experiments were made
over the cable between New York city and
Canso, which had length of S27 knots, and
electrical resistance of 1900 ohms, and an
electric distributing capacity OF 23l micr'
fards. These tests were made between
September 25 and October l6, 1896.
The change from existing telegraph meth
ods consists in the substitution for the pres
ent appliance of a transmitter sending
smooth waves, such as are obtained in al
ternating currents working, without making
any other changes whatever in the elements
of the present system. The conditions in
the transmission of messages over long ca
bles are distinctly and widely different from
those on aerial lines. The necessity Of in
creased speed over ocean cables, the report
continues, while not generally appreciated
is strikingly obvious when examined from
spanning the Atlantic costs several million
dollars, the value of any discovery that will
increase the working power. Of the cables is
at once apparent. General Greely says. he
has no hesitancy in expressing his opinion
that the Sine wave system, which also ad-
mits of easy duplexing. will, within year
or two, increase very materially the work
ing capacity of every cable to which it is
applied.