New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1900-09-16
TTRELESS TELEGRAPHY.

Several achievements in Hertz wave teleg
raphy have recently been reported which appre-
ciably improve the scientific and commercial
status of that art Perhaps the most important
of these is the extended practical test given to
the Marconi system in South Africa by the
British army and navy. During the early part
of the late war no use was made of wireless
telegraphy, owing TO the prejudceS or cOnServ-
atsm of General Butler and other high officers.
But when General Lord Roberts took command
a more progressive policy was adopted. Ten
sets of instruments were procured and retained
in service In this manner headquarters were
kept in constant communication with detach-
ments of the army. some of which were fifty
and sixty miles away. By the same agency the
British Admiral al Delagoa Bay was enabled to
send messages eighty and even hundred miles.
1t is recognized that the interposition of hills
between stations on land sensbly diminisheS
the range of a transmitter of a given capacity.
Official tests which have recently been pre-
scribed by the British Admiralty for new inStru-
ments ordered for the navy require that the
latter shall be operated successfully between
Portland and Portsmouth HarbOr, which are
sixty five miles apart. But intervening obstruC-
tons make this interval equivalent TO eighty
five miles at sea, in Mr. Marconi's opinion, and
to ninety miles in the opinion of the Admiralty.
In spite Of the Limitation referred TO, however,
It has now been demonstrated for the first time
that military campaigning does not offer any
insurmountable obstacle 10 the use of wireless
telcgraphy.
incidentally 1t is worthy of note that the
range OF the transmtter at Delagoa Bay was
something like twenty miles greater than that of
the apparatus used by Marconi experimentalIy
early in the summer OF 1899 with the British
Channel Squadron and four or five times greater
than that OF certain Instruments which have
lately been tried at British torpedo station.
These latter, devised by a Captain Jackson,
might possibly have been adopted if they had
worked better, and thus the payment of royal
ties TO MarCOni would have been avoided But
the order just given for thirty-two full sets OF
the young Italians instruments is an official ac-
acknowledgement Of their conspicuous superiority
Marconi has Of late been industriously trying
To secure that secrecy of communication which
was hoped for as one of the great advantages
Of the new system. Hitherto it has been pos
slble for an enemy, If provided with a Hertz
wave receiver and stationed within range of
the transmtter to pick up a message not in
tended for him. But The Scientific American"
is authority for the statement that the idea of
tuning transmitter and receiver to the same
pitch, or number of waves a second has been
worked out practically, and that only n coherer
which has been synchronized with the spark
coil will respond to the vibrations emitted by
the latter. This Is highly desirable In war and
it is TO be hoped that the announcement is
correct.
In the mean time wireless telegraphy Is serv-
ing, and promising to serve, purely peaceful in
terests to an increased degree. A number of
ocean liners and Channel boats are equipped
with MarcOni instruments In order to announce
their approach to the coast. Lghtships employ
the same means to report wrecks and summon
aid from life saving stations on shore and only
few days ago London newspaper described
a successful test of automatic device for
warning vessels in n fog of the proximity of
dangerous rocks. A transmitter capable of
sending out waves for seven miles was operated
by clockwOrk and made to repeat the word
"Fastnet at intervals Of three minutes A shin
on which there n Marconi receiver and
which came within range of the signal would
learn OF its peril in ample time to save itself
AS yet this particular invention has not been
officially installed at any lighthouse; but such
action is almost sure to come. because the pene-
trating power Of the Hertz waves In n fog "a
vastly greater than that of either an electric
light or the sound of the best steam foghorn in
the world