The sun. [volume] (New York [N.Y.]) 1833-1916, 1914-07-05
The Herald Square Theatre to-day
SOUND WAVES MAY ELIMINATE PERIL OF FOG AT SEA

It's aid sound originating twenty miles
away can be heard as II It's source were
but two or three miles distant
Between our ears Is a stretch OF about
eight inches. When we hear a sound
on one side we instinctIvely turn and
face II squarely. II both ears are equally
acute the nose points directly at the
source Of sound when each ear hears
that sound alike The sense OF direc-
ton lies in the ear and the distance be-
tween the ears Is the base line from
which we do our audible surveying. The
converging lines starting at equal angles
from each ear meet at the point Of dis
turbance OF the air. This base line In
pretty short and therefore any defect In
one ear is apt to impair the sense Of
direction when unaided by the ego. Tho
longer tho base line the more accurately
the angles Of the two converging sides
Of the isosceles triangle can be deter
mined.
How does Mr.. Ries extend this base
line so as to overcome the limitations
imposed by mans physical makeup? In
brief. he would put pair of mechanical
ears upon every seagoing ship and the
base limo would be as long a. tho ship
Ia broad.
TOT MS puSo llno Mr.. ftioa uses .
hollow rod or pipe hung athwartship
upon the foremost like signal yard
and mounted well up In the air, say
at point above the lookout's crows
nest. This spreader or signal yard IL
to he SO installed that It can be rotated
freely In a horizontal plano. Now for
tho mechanical ears.
At each end OF tho spreader he
A. nj An -
these are pivoted so that they, too, may
be moved horizontally turning uni
formly and simultaneously from directly
ahead inward toward the apex Of an
imaginary isosceles triangle. The length
wise axes of the megaphones lie on the
two lines of the imaginary triangle
built upon the base line OF the spreader
and meet at the distant source Of sound.
Sound waves just like beams of light
are reflected from suitable surfaces. II
you throw your voice toward a defect
Ing surface. standing forty-nve degrees
from that surface. the echo will be
thrown of at forty-five degrees and
away from you. You will not hear the
echo. II you stand squarely in front Of
the resounding surface the echo will
come back to you Just as would base
ball thrown similarly against a con-
fronting wall.
Mr.. Ries aims first to pick up a warm
ing sound. the whistle of a faraway
ship, the echo OF the ship own fog
horn. the booming Of the surf, the bell
or blast OF an automatic buoy. To do
this the spreader OF the detector Is
swung about it's horizontal axis slowly
from side to side hunting for a sound.
When sound is caught by either re-
ceiver that fact gives the general d.
rection of the source. and then the
spreader IL swung until tho audible
signal comes with equal cIearness
through both receivers.
| Even then. however. the tone Of the
faraway whistle or the detected echo
may not be exactly In focus: It may be
mufiied or indistinct. Now by moving
! the megaphones slowly inward at an
angle their axes can be brought d.
rectly in limo with the advancing sound
/ waves and at once this fact Is noted
| by the lookout through the SHARPNESS
/ Of the received signal. In hunting for
the cause OF the sound In this manner
the lookout 10 automatically fixing Its
| Cnaflnaad ma Rnuef.n.sk No.