EXACT SHAPE OF EARTH

Evening Star, Issue 20135, 27 March 1929, Page 6

EXACT SHAPE OF EARTH

SUBMARINE EXPEDITION PROBLEM FOR SCIENTISTS. Equipped with delicate instruments and having aboard eminent scientists skilled in their use ami operation, the. American submarine H2l has set out on a mission which is expected to solve the old question “ What is the shape of the earth?” In this submerged laboratory the picked groups of scientific observers will watch carefully over the functioning of an apparatus which photographs the timed swing of a pendulum which determines the force of gravity and records thereby the precise contour of the ocean’s floor. The personnel of the expedition indues the famous Dutch scientist, Dr F A. Veiling Meincsz. professor of geodesy of the University of Utrecht, as chief, with Dr Frederick E. Wright, of the Carnegie Institution of Washington, and Dr Elmer B. (,’ol--1 ins, principal scientist of the Naval. Hydrographic Office. In addition to the ingenious pendulum apparatus brought to this country by the Dutch scientist, the S2l is equipped with an improved sonic depth-finder and other instruments with which to record all observations made. Actual measurements of intensity or gravity to obtain outlines oi the earth have been made in a lew restricted ' tracts in continental aieas. and, 1 bough they have included only a I faction oi the earths surface, from those have been drawn onr idea, of the. size ot the earth. Until the development of Dr Moinesz's instruments, it has been impra-tic-ahle to obtain sneli measurements aft sea. Even Ids instruments cannot be used except on a submerged submarine. where, the minimum motion from the sea is experienced. Tim ordinary ocean swell _ caused, movements too great to bo eliminated, within (he capability to any pendulum, device- so far designed, hut in a. ship submerged below the influence, of wave action a, sufficiently steady platform is assured lor the snccesslnl operation of Dr Meinesz’s instrument. Thus the submarine is the solo agency known t) science for accomplishing the investigation essential for detei mining the contour of the earth under tho sea. Tins is a problem that has intrigued astronomers, geodesists, and other scientists since Eratosthenes, more than 2,000 years ago, employed as data, the gnomons of Alexamfria. and Syemi and the stadia betwen.Essential to the investigations is nob only the submarine’s power to submerge, but its ability to receive, turn* signals by radio and to take soundings af great depths by means of the. sonic depth-finder. Through the records of this instrument an •accurate profile ot the ocean bed may he made simultaneously with the measurement ot gravity 'of that area. . The region to he traversed is one of the most interesting of the earth from a. geophysical ami geological, standpoint. It is believed that the islands of the West Indies arc comparatively young, geologically speakiiie. The ocean waters surged over the places now occupied by these islands in the net-distant past. V haft caused those uplifts of the, islands and what caused the. great ocean deeps that lie among them ? These are prohUmis on M'iiirli avo bnvo boon nbl<? to speculate only, for we have not had the necessary fundamental data on which to build theories and to give logical explanations.