Evening star., 1928-11-28
.ME|NESz PROBES
RIFFS IN SEA BED
Evidence of Earthquake Be.
tween Americas Seen
by Scientist.
BY the Associated Press.

BY the Associated Press.
Evidence of a great earthquake, pro-
ducing stresses in the earths crust be-
tween North and South America, has
been brought here by DR., F. A. Vening
Meinesz, world famous Dutch geo.
desist, after a two-month cruise with
the Navy scientific expedition aboard
the United States submarine Sal.
With this evidence, much of it hither-
to unknown to science, comes q sug-
gestion that the two continents are
pressing, imperceptibly, but with meal
culable force, toward each other, 1t
discloses clearly, DR.. Meinesz says, that
the same kind of stresses which, in
past geologic ages piled up mountains
and left deep scars on the continents
until equilibrium was reached, are still
exerting their awe-inspiring power be-
meath the oceans.
The most striking discovery of the
expedition was the existence OF a great
rift in the earth's crust extending
through the 4,700 fathom Mares deep,
north of Porto Rico, westward to q
point north of the eastern end OF Cuba,
Similar unstable conditions were dis
covered, to the scientists surprise, In
the extensive so-called Sigshee deep, IN
the southwestern part OF the Gull OF
at all, but merely the deepest part OF
the gulf, reaching down 1900 fathoms,
or more than two sea miles. Like
stresses also were found between Cuba
and Jamaica, In the Bartlett deep
which goes down 1850 fathoms.
Uses Delicate Apparatus.
The existence of these stresses was
discovered by measuring variations
from normal in the force OF gravity
in the ocean bed with a complicated
delicate apparatus devised by DR..
Meinesz to make such determinations
possible at sea. This device makes
use of the we'll established knowledge
that the pull of gravity can be meas
ured by its effect on swinging pendu-
lum, Instead of single pendulum
which can be employed effectively on
land, the Meinesz apparatus includes
three, swinging in different directions,
permitting accurate observations when
the pitching and rolling of the SUBJ
marine in which 1t Is mounted has been
sufficiently modified by submergence to
a depth of rs or 80 feet. A sonic depth
finder also was used throughout the
trip.
The expeditions cruise covered 1000
miles along the continental shelf from
Norfolk to Key West, thence across the
Sigshee deep to Galveston, Tex, over
the Mississippi delta back to Key West
along both sides of the ridge OF islands
represented by Cuba, Haiti and Porto
Rico, and back to course which took
the
continental shelf.
Submerges 40 Times.
| In all, the submarine was submerged
40 times for gravity measurements, five
being made within 10 hours in the Bart
| lett deep. In addition to DR.. Meinesz
| the scientific work was carried out by
DR.. Fred E, Wright of Carnegie Institu-
| ton of Washington and Elmer B. Col
Inns of the photographic office OF the
Navy, The Navy furnished, besides the
Sal, two eagle boats for tenders, with
Capt, r. l.. Nash in command ano
Lieut.. James J., Fisher In charge OF the
| submarine,
The expedition was expected to re-
| turn to Washington today, but having
! encountered exceptionally rough weather
on the return trip and seeing chance
to navigate the Potomac yesterday
| Lieut.. Fisher brought his submarine to
/ the Navy Yard late yesterday, The
data gathered were promptly turned over
| to the Coast and Geodetic Survey, fol
more accurate computation of the re-
suits than was possible during the
! cruise.
| These results are expected to be oi
| great value to various Government
agencies and to contribute eventually
toward the development of means OF
forecasting earthquakes and similar
disturbances. They represent the first
participation by any government ex-
cept that of the Netherlands in what
scientists and naval authorities hope
will become a worldwide survey ot
gravity variations beneath the oceans
which are essential to thorough
knowledge of the form and forces III
i tlan artlalc nfllst