The recent development of a diving bell, designed to carry a gravimeter and observer, enables the geophysicist to make correct gravity observations on a river, lake or ocean floor. The bell, for which patents have been applied, is designed to operate in depths of water as great as 250 feet. It has been used with good results at depths ranging from 8 to 70 feet. Data taken from adjacent land and sea areas have been contoured and the smoothness of the resulting contours indicates that the underwater gravity readings are entirely reliable. Structural features of the diving bell and related equipment are described and plates showing exterior and interior views of the bell are given.