Evening star., 1924-01-05
RADIO WAVES PIERCE
80 FEET UNDER RIVER
Test in Hudson Tube to Prove Of
Enormous Benefit to Miners,
r. Said.
PROGRAM COMES IN CLEAR
Portable Sets for Use Under
Ground Demonstrated.
ny the Associated Press.

ny the Associated Press.
NEW YORK, January 5.-Huddled
In a dripping tunnel ninety feet be-
low the surface of the Hudson river
and 1,60o feet from an exit. a group
OF transit officials, electrical experts,
sand hogs and newspaper men to-
day tuned in on radio concerts broad
cast from Pittsburgh and half do1en
nearer stations. The experiment
was conducted at the farthest end
of the uncompIeted Jersey Manhat-
tan tube Of the dual vehicular tunnel
by. technicians of the Radio Corpora
tion of America, the Westinghouse
Electric Manufacturing Company and
the New York. New Jersey Bridge
and Tunnel commission.
The radio programs were heard dis
tinctly. both by ear phone and loud
speaker. The fact that the ether
vibrations carried into the tunnel
penetrating thirty feet of water. six
y feet of earth and several inche
or steel demonstrated. said those in
Charge of the experiment that the
radio could be used as life line of
communication by entombed miners
or deep sea divers.
This c"nvinces us that the future
VIII enable our divers and caisson
I3nreriled when the telephone lines
they communicate with are swept
away to carry small portable radio
. transmitting and receiving sets which
VIII make them independent of all
otner means of communication" said
NJ. VI. Frohlich. secretary of the New
Aork state bridge and tunnel COM
mission, who Instituted today's tests.
Demonstrates Small OUTFIT.
u. Y. Allen. radio technician for the
Westinghouse Company. predicted
the experiments demonstrated the
rraGticability of miniature radio o
outht that already had been designed
Tor the protection of the miner.
The telephone is now the deep
mime workers only means of COM
municating with those above ground
said Allen. IF there's an explosion
telephone lines usually are disabled
also. The entombed miner is unable
10 tell his reScuers where he Is, what
has happened, what gas hazards there
may be, what has been the fate Of
his companions, or to direct those
burrowfng to his aid.
The radio should take most Of tho
hsphazard out of mine rescue work"
Today's test-called the first sue
cessfu underground reception of
fadlo, although several unsuccessful
amateur experiments have been re-
ported from Pennsylvania coal mines
was condcted with standard stock
apparatus. The programs heard were
the regular afternoon concerts of
nroadcasting stations here and in
Pittsburgh.
Comes In Clearly.
The Pittsburgh music came clearly
and with normal intensity over the
head phones. but less distinctly from,
the loud speaker. The local concerts,
however, came so loudly over the
ampliher that they were heard 200
Feet away at the steel lock" which
maintains high pressure inside the
tube, and in which sand hogs" suf-
ferlng the bends" are gradually
brought under normal pressures
Strangely enough, the 6rst number
moked up was lecture on "Sa afety
solo, with violin, which came so dis
tinctly over the loud speaker that
editors several miles distant heard it
over telephones connected with the
tunnel head.
Technicians present differed as to
how the radio registered within the
tunnel. Some believed the waves of
energy penetrated the steel walls.
after having permeated the everything
ninety feet OF water and mud. Others
believed that the energy waves,
rapidly circling the thirty-foot di-
ameter cast-steel jacket which forms
the tunnel, made of it a gigantic
'multiwfre COIL" setting UP a high
frequency current which Induced a
similar current inside the tunnel. and
which in turn induced a reaction in
the radio receiving apparatus identi-
cal with the reaction experienced in
HEARD RADIO TN GAVE