Velocity of Sound in Sea Water

Abstract

Velocity of sound in sea water at - 0.3\ifmmode^\circ\else\textdegree\fi{}C. over a distance of about 15,500 meters through the waters of Block Island Sound, New York, was found to be 1,453 meters/second, by determining the time for the sound wave produced by the explosion of a bomb to travel to each of five hydrophones anchored at widely separated points, and the distance travelled in each case. The time of detonation was transmitted by radio, and the times of arrival of the wave by cables from the hydrophones to a string galvanometer whose deflections were photographically recorded, together with timing lines at intervals of 1/100 second. The distances were determined by triangulation from two bases on shore. The depth varied from 18 to over 50 meters. The results from the five independent determinations for each of four bombs all lie within \ifmmode\pm\else\textpm\fi{} 0.2 per cent. of the average, indicating that the sound wave had a uniform velocity. It is expected that further studies will enable the effect of variations of temperature, depth, salinity and density on the velocity to be determined.