Apparatus and procedures are described with which seismic reflections have been obtained from the ocean bottom and from deeper horizons. The area surveyed lies between Bermuda, the Greater Antilles, and the United States. All records obtained in an east‐west strip, 70 to 80 mi wide, extending from 61° W longitude south of Bermuda to 71° W longitude and thence southward as a strip 200 to 300 mi wide to about 23° N latitude, show a single prominent reflecting horizon at depths exceeding 500 ft below the bottom (assuming the seismic velocity in the bottom sediment to be equal to or greater than that of sea water). In this area the bathymetric data indicate that the bottom is either flat or relatively smooth. The records from other parts of the area are, with few exceptions, more complicated, correlating with bathymetric evidence of a rougher bottom there. A system is outlined for classifying reflection records obtained in deep water with suggested geologic significance of the various record t