The daily star-mirror. (Moscow, Idaho) 1911-1939, 1919-05-10
War INVENTIONS
COMING TO LIGHT
Many Interesting Achievements
Are Now Being Made
Public.
SEAL OF SILENCE BROKEN
System Of Sending and Receiving
Wireless Telephone Messaoss At
Same Time and 4 Barrape Re
celver Among Novelties.

New York.-As the seal placed upo1
the activities of Americas inventor,
by the war Is broken, news Of many In
teresting achievements unknown to tn,
public during the conflict are bsinl
brought to light. A system Of sendinl
and receiving wireless telephone met
sages at the same time, as Ii done II
wire lines; q "barrage receiver" which
shuts out the sound Of all wireless VI
bration except those which the opera'
tor wishes to hear, and 4 system Of
rapid and accurate photography Of
wireless message became known to the
public for the first time recently, al
though government naval stations have
been experimenting with them Tor
some time.
Engineers Of the General Electric
company at Schenectady are responsi-
Bile for each Of the inventions. Ernst
f. w. Alexanderson, consulting en-
gineer Of the company, told Of the de-
velopment Of the barrage receiver and
wireless telephony Ideas at meeting
of the Institute of Radio Engineers at
% West Thirty-ninth street recently.
@. A. Hoxie of Schenectady, another
General Electric company engineer. u
the inventor Of the wireless photo
graphic apparatus.
Sending and Receiving.
Doctor Alexanderson told the engi-
neers that obviously some system of
simultaneous sending and receiving
would have to be invented before wire
less telephony would ever become COM
mercially practicable. Switching from
one apparatus to another to send and
receive would be annoying and delay.
ing. For instance, the user Of the telo-
phone on this side of the Atlantic says:
"Hello" into the mouthpiece. Then
he has to switch to another apparatus
to catch the answer from Europe. And
perhaps his friend overseas Is doing
the same thing, and the attempt 1t
conversation develops into sert Of
game. There was also
the problem Of bringing the wireless
telephone to the home of the user. II
one has to travel to Washington or
New Brunswick to use the wireless tel
ephone 1t is scarcely a saver Of time
or money.
Doctor Alexanderson has devised .
system of separate sending and re-
ceiving antennae, the sending and re-
,eiving stations interconnected by q
wire line and further connected to the
exchange Of the local telephone syo-
.em, SO that all Mrs. Jones has to do
when she wants to find out what Mr..
Jones is doing in Paris tonight is t.
20 to her telephone and ask, not for
oh operator, but for the wireless op-
orator. he will connect her with Mr..
Zones.
The Barrase Receiver.
The invention Of the barrage re-
eiver came about as a result of the
onfusiOn into which the wireless ma
hinery was thrown during the war.
through her powerful stations at Nam
en- and elsewhere Germany was mali
iously flooding the atmosphere with
wireless noise" SO that communica-
ions between France and England
nd America became very difficult.
was completely drowning out
he voice of Americas allies The In
erallied conference in February, 1918,
ought way out Of the difficulty, and
ppeals for a solution were brought to
'octor Alexanderson by Lieutenant
aternot Of the French mission in this
ountry. The solution, which was
1opted by the French and American
overnments after It's first demonstra-
on was called the "barrage receiver"
scause the word ''barrage" has the
iginal meaning Of stoppage proven
on. The barrage receiver success
llyl shut out the vibrations sent out
ON Germany with the object Of de-
roying the allied intercommunica-
on. It's principle can be compared
that of an instrument which, II ap-
led to the ear, would silence the
lrieking of steam whistle ten yards
way, while enabling the listener to
ar perfectly the spoken word hun
ed yards of Aside from its war
ne use the barrage receiver has ex-
nsive possibilities for peacetime de-
lopment. Through It's use the num-
r of communications that may be
rried on without disturbing each
her may be multiplied greatly.