Wauwatosa news. [volume] (Wauwatosa, Wis.) 1900-1948, 1903-09-26
WIRELESS NOT SECRET.
Marconi's Method Like Telegraph Sig
naling-Hertzian Waves Vary
in Length.

The claim TO perfect secrecy of wireless
messages suffered another shock last
week during the yacht races. when the
Marconi and the De Forest wireless mes
sages were interefered with by some
scientific Hooligan'' as Prof. Fleming
would call him. The scientific world is
still chuckling over the clever work Of
Neville Maskelyn in upsetting Prof
FlemIngs claim that tuned messages
could not be intercepted or interfered
with, and the trick was justified on ac-
count of MIR. Maskeiyn's motive and the
fact that he did not maliciOusly interfere
with Prof. Jennings lecture. Mr..
Maskelyn's unknown imitator in this
country, however, went to Il spiteful ex-
IRENE Ill entirely interrupting with floods
OF profanity and obscenity the news for
which the public was eagerly waiting.
The perpetrator of such cowardly deed
should be vigorously prosecuted, the act
beng similar to that of seyering tele-
graph or telephone wires. The difficulty
OF experimenting such yandals will al
ways be great, and for this reason the
question of safeguarding wireless mes
sages should receive renewed attention.
The fact that tuning of system has failed
TO accomplish all that was required of it
Is confirmed by the statement of the De
Forest company, that prior TO the races
an understanding was entered into with
the Marconi company whereby their res
spective systems should not be worked
simultaneously to interfere with each
other. The character of the telegraphie
signals received on these two systems is
very different. In one system the dots
and dashes are short and sharp; in the
other they are of much longer duration.
and we are informed that it is possible
for two operators to receive on one re-
celyer messages sent simultaneously from
Marconi and a De Forest transmitter,
provided one operator devotcs his entire
attention to the Marconigram while the
other pays strict attention 10 the De For
est message. Now if, with systems so
different IN character, it was thought best
to make arrangements for nou-interfer-
ence, how much more necessary would it
have been to prevent interference in sys-
tens using approximately the same
length of telegraphic signal.
Wireless telegraphy is essentially SINH
lar to photographic signaling. AS the
Hertzian waves are invisible, there is
used in wireless telegraphy an electric
receiver which Lord Kelvin has APPLY
called the electric eye" To carry out
our comparison, all efforts so far have
been made to cause the light flashed out
to have such "A wave length or color as
the electric eve" is best adapted to re-
ceive. The failure of this attempt is due
to the fact that the electric eye"
does does with varying efficiency
receive Hertzian waves of greatly
varying lengths, the difference in efti-
cheney being too slight for practical de-
lection. One thing seems to have been
forgotten-the EYE" as now arranged is
capable of receiving waves from every
point of the compass, and similarly, the
transmitting station spreads out its
waves to all parts of the horizon. Why
would not practical solution of the diff
tculty be the use of a lens for focusing
the rays directly on the electric eye"
and Furthermore, Of providing electric
spectacles' as someone has called them,
for the electric eyes" themselves? 1t is
well known that Hertzian waves can be
readily focused by the use of lens made
of pitch, and such an arrangement would
cause the electric eye" to see most plain
~ those rays sent from one particular
direction, while all outside sources of
Hertzian waves would affect it to a COM
paratiyely small degree. If necessary.
these rays might be screened off by a
screen of wire or plate metal.-Scientifc
American.