Evening star., 1902-01-02
WIRELESS TEtEGRAPHY
WILLIS MOORE COMMENTS ON TINE
MARCONI EXPERIMENTS.
Diherence Between Signal. and Mes
snses-Some of the Difficulties
Yet to Re Overcome

MI Willis S. Moore. chief of the weather
bureau. In speaking of wireless telegrapbv
today said:
heartily join in applauding Marconi's
success In transmitting signals across the
Atlantic ocean. In this connection how
ever, l must say that there is a great dr.
terence between the sending of a signal
ana The sending of a message and lam
OF the opinion that a great deal must Vet
De done before messages can be success
fuliy transmitted across the Atlantic. IL
VIII lirst be necessary for the Marconi sys-
teln' or any other system, to put into sue
eessfuily daily working order stations oper-
ating over distances of 800 miles or more
So far neither Marconi nor any one els.
mas constructed apparatus even for work,
ing over short distances that has not grave
elements of defect and unreliability. / am
enthusiastic In believing that the time will
come when wireless messages will no se,,t
over considerable distances but our peo-
PIE nave already anticipated all Of The de-
Nelopments that will probably result from
experiments Tor many years to come 1
learn that Mr.. Marconi himself has been
very careful not to say that he had sent a
message, but only that he believed he had
nave sent signals over long distances even
on land, where it was impossible to make
our Instruments transmit letters in CO.
herent sequence.
some D1mcultfes to BE Overcome.
Let us look at some of the difficulties yet
| to be overcome before transoceanic mes
sages can be sent and received. First,.the
kite must be dispensed with, because itswin
only fly when there is wind Second,s the
balloon must be discarded, because it will
not rise in a captive condition to any great
altitude, as the wind on the cord and bal
loon drives 1t away at a low angle; aud IL
some stable means of elevating the reeeiv-
ing wire to a great height is devised or il
apparatus is perfected that does NOT re-
quire receiving wire of great elevation
the almost insurmountable difficulty OF in
terference remains, and messages could NOT
De transmitted unless some company CON
trolied the ocean and had the power TO
prohibit any transmitter from emitting
etheric waves between the Europeanesand
American shores, for it is a well-kffoNn
tact that two Instruments cannot SUCCESS
tully operate within the same magnetic
Held. The field that We are now consider
ing Is one bounded by two great continents
1t VIII be impossible for any company TO
control the ocean and to exclude other
systems from transmitting signals and
therefore, interfering with messages in
tended to cross the ocean. Hence after
the dlfhculties of elevating the transmitting
and receiving wires have been overcome ir
VIII be necessary to perfect a system of Sc
iective telegraphy, whereby messages can
De differentiated and only the receiver thar
1t is desired shall receive the message he
come responsive to the waves of ether he
lore the messages can be sent across the
Atlantic with sufficient reliability TO have
commercial value. All this will require
much experimenting.
System of Selective TeIcSraphy.
III system of selective telegraphy cam
not be perfected, so that one system Will
not interfere with, and render useless. an
other system and thereby deprive COM
merce of the use of recent discoveries I'm
wireless telegraphy. 1t may become neces-
sary, on account of the value of these dis
coNer1es to marine interests. for our gov
ernment to take exclusive control of all
systems of etheric space telegraphy and TO
establlsh stations along our extensive coast
lines at such distances and i'm such relation
the one to the other that they shall not
interfere. Even then there will be occa-
sional difficulty I'm communicating with the
mainland whenever two ships in close proN-
unity are attempting to transmit messages
at the same time or whenever two adjacent
ships are attempting to receive messages
from two different transmitters. Mr. Mar
conf has already performed wonderful
service, but do not believe that he Will
claim that the difficulties herein referred
to have been overcome, or that they are
likely to be overcome in the Immediate
future