Evening star., 1928-11-23
NEW SEA DEVICES
4. RECEIVE APPROVAL
Coast and Geodetic Survey
Director Describes "Echo-
Sounding" Process.

Echo sounding through water and
radio acoustic sound ranging were given
public presentation and official in
dorsement" today by Col. E. Lester
Jones, director of the Coast and Geo
detic Survey, in his annual report TO
the Secretary of Commerce, describing
their use In coastal waters.
These n1arvels of modern science, il
was explained, enable ships to measure
and locate ocean depths with the aid
of electro mechanical devices which
send out impulses through the water to
the ocean floor. and also to points on
shore.
Col. Jones also declared that despite
an increase of 400 per cent in eight
years in the volume of survey work ac-
complished, the survey expects further
to broaden its activities in the East and
along the Atlantic Coast. The increase
will be made possible by addition to
the survey fleet of one new ship, now
under construction. and also through
development of under water commune
cation devices. The Atlantic Coast fleet
next year will consist of four instead
Of three ships.
Resuryey Needed.
"There is need for completing a re-
survey of those Atlantic and Gulf
Coast waters constantly traversed by
coastwise shipping" declared Col Jones.
Present charts of the area are con-
structed largely from surveys made 60
to 80 years ago, based on the require
mentS of comparatively small sailing
ships. Such charts are partly made
Quate for modern deep-draft steamers.
In addition. on this comparatively shall
low coast natural changes would have
made the best of surveys of that age
TO some extent obsolete"
Discussing personnel questions, Col
Jones declared the WEIGH act was
"step in the right direction" but that
'other and more liberal legislation
should follow"
Higher pay for civil service person.
mel, he said, is simply the logical solu-
ton to the problem of increased eff
cheney in the conduct of Government
business"
A comprehensive. tide and current sur
vey of Chesapeake Bay was in progress
at the close of the fiscal year, the report
states.
Development Described.
Reporting that eight of the surveys
13 ships are now equipped with echo
sounding apparatus known as the faith
Ometer, Col. Jones described this de-
velopn1ent as follows:
Echo sounding depends on the fact
that if a sound is produced under water,
an echo will return from the bottom.
BY measuring the time interval required
for sound to travel from the huh of
ship to the ocean floor and return to
the ship, and multiplying by one-half
the velocity of sound in water, the
depth of the water is determined
Sound travels much easier and faster
in water than in air. A sound made at
the bottom of a ship will travel to the
bottom of the ocean and back through a
thousand fathoms; or a depth of more
than mile of water, in two and one
half seconds, the velocity of sound in
water being about 4,800 feet per second.
by the use of the echo sounding ap-
paratus, more than twice as much area
per day can be surveyed than would be
possible by any other known means.
Soundings can be taken in any depths,
from few fathoms under the keel to
$500 fathons Q6,800 feet). or more,
while the vessel is going ahead at full
speed"