Evening star., 1923-02-04
Nv COMMANDER STAMFORD c.
HOOPER, L. s. y.


VIII American scientists discover
the cause of earthquakes and disas-
trous tidal waves and triumph over
them as they have already triumphed
over such plaques as malaria fever,
for example
If they do. radio will possibly have
contributed, at least indirectly. in
this accomplishment.
Investigations along this line have
recently been made by the Carnegie
Institute of Washington. acting IN
conjunction with the Navy. and util-
izing the Navy's recently perfected
sound wave system, which system is
closely related to radio.
The science of sound waves may
he said to be the first cousin of the
science of radio.
Ns is generally Well known. tn,
ether waves of radio telegraphy and
l'adio-te telephony. including radiophone
broadcasting. or today are not per-
"ept'blc- to our senses. but are made
50 by these radio waves creating
sound waves in turn.
Sound Waves Propagated.
Thus We do not actually hear the
radio waves in the telephone heaG
pieces or loud speakers used to ma @
the incoming waves audible to our
sense of hearing. but on the contrary
we hear sound waves as set up by the
diaphragmS of these instruments as
y result of the incoming radio waves,
these sound waves reproducing the
equivalent of the ether or ra dio waves
ON the other hand. in the Navy $
newly developed system of sound
waves the sound waves themSell eS
are propagated through water or 9TH
er media by utilizing instruments to
ia IL 6,stl. Il f,f
radio. and detecting the sounds. o"
their echoes. by employing sound re
cejNcrS or hydrophoncs.
Thus. while the functioning OF ra
III" for most practical purposes * dc
pendent upon sound waN eS, til" .'tn,-
rioning o: the sound system i; de
pendent only on sound waves, which
travel at the comparatively slow r:t'
of speed of approximately t.tt9 feet
per second. and entirely Independent
Of ether or radio waves, which travel
with such rapidity as to encomDa IS
the globe seven times in aprroX,-
matcly one second of time.
L. =. Navy Apparatus.
However, the services of radio op-
orators who are competent in recei,
ing incoming radio signals are desir
able if not necessary for best results
in sound work.
As is well known. earthquakes oo-
cur more or less frequently at points
situated along our 'aciti. selhoard.
the extremely destructive san Fran
cisco earthquake and resulting ire
being case in point.
At the request of the Carnegie In
stitutc of Washington. a survey was
held along our Pacific coast from
Point Descano. Mex. to San Francisco,
Calf, extending from the 100-fathom
curve to the floor of the Pacific
ocean. utilizing the Navys recently
developed sonic apparatus described
in my articles of July >. 1922, and
November II. 1922. installed on the
/, dcstroyers Hull and Cory.
The scientists of the Carnegie In
stitute desired to obtain data for the
construction of an accurate contour
map of the Pacific continental shelf
an aid in the institutes research
in locating the faults likely to cause
earthquakes in this area, and the
Navy desired to check up on the
Soundings previously made within
his area by the old. laborious and
Extremely slow and costly methods
used in the past. in the interests of
safety of navigation in these waters.
Covers Huge Area.
That the proposed Investigations
constituted a project of some magni-
tude will be apparent when it is
realized that the area under consid
GRAFTON comprises about $4,000 square
miles.
To undertake a project Of this ma