The sun. [volume] (New York [N.Y.]) 1916-1920, 1919-03-23

of other questions were asked and an
swered.
More experimental stations were es-
tablished-one on the Mohawk River
near Schenectady and another on the
Erie Canal.
Meanwhile in tho guarded labora-
tories experimentation still continued
"Progreee" was the one word which
emanateC rom behind the closed doors
always progress.
At last, twelve weeks after expert
mentation had begun. the engineers
had perfected an instrument which
they believed would meet all demands.
A new device for detecting subma-
rines-a development Of the American
mind and one Of this countrys great
est contributions to the war had re-
suited from their labor.
From Ear to Ear.
ciple Of sound wave transmission
through the water, and depends for
its direction getting quality on the
peculiar, and heretofore little under
stood. faculty OF the human ear to
detect the direction Of sound by the
shifting OF sound from one ear to the
other.
4 So important was this human eQua-
ton in the proper use Of the instru-
ment that one Of the first things done
was to establish a school fors sub
marine listeners at the Nahant station.
which was attended by score Of
IL Go nd or,Ik Cto Oh
men. Among the first students was a
group of French sailors.
The listening device was first de-
signed to be hung overheard amid
ships below the water line. The OBJ
server was stationed on deck. Later
the instrument was fastened to the
hull OF the vessel and the observer
took his position within the hold, the
connections leading through the side
Of the ship.
1t soon was discovered that the rock
ing Of the boat in heavy weather seri-
ously affected the range OF the device.
ships side interfered at times with the
operators observations. but these OBJ
stacles were later overcome.
During the experiments II was found
necessary to stop the engines in order
that accurate observations could be
taken. The stopping OF the engines
led to the elimination of extraneous
sounds and edded considerably to the
effective range OF the instrument.
For heavy weather conditions a tow
ing device. or trailer. was invented
which dragged the listener through the
water astern.
The engineers were now ready to
test the practicability of the device
under fire." and further experiments
were carried out under conditions as
nearly as possible approaching those
in European waters.
The navy submarine station at New
London despatched a fotilla of under
water craft and a squadron OF sub
marine chasers to Boston waters The
chasers were equipped at Nahant with
submarine detectors and practice be-
gan in real earnest.
Tho First Demonstra ton.
In spite Of It all, initial experiments
proved slow Of entirely satisfactory
developments until the fall of 1917,
when It was decided to go out to sea
off Cape Cod for more thoroughgoing
tests.
The sea was clear of craft as far as
the eye could see-yet tho~N orator
with his ear to the detector distinctly
heard a vessel approaching-nearer
nearer-nearer. The Captain from the
bridge eagerly scanned tho horizon
with the ships glasses-nothing In
sight.
Send man sloft with powerful
glasses" he commanded. 1.-THE de-
tector has picked up a craft three
points on our starboard bow"
The sailor returned. Nothing in
sight. SIR"
Ill go alott myself. That boat
sounds as If IL wore very near. Why,
we can hear her engines as clearly as
II she were alongside"
Puzzled, the Captain returned from
the masthead after a disappointing
vision of a calm and perfectly clear
| sea
"How's she coming7" shouted the
First Lieutenant down the hatchway
Heading straight for US, sir Sound
getting louder every minute"
There was nothing to do but wait.
The Captain pulled out his watch
and sat down. Fifteen minutes-half
an hour-an hour-ticked on.
ship ahoy!" came from the mast
head.
"Where away?-
"Two points on the starboard bow
sir. Looks like she was heading this
! The vessel had been detected by
sound waves travelling through the
water. her course and speed had been
accurately charted and her exact POSI-
ton within ono point OF the COMPASS