In an earlier communication in this Journal the writer reported on a Bathythermograph for obtaining continuous records of temperature against depth in the first 150 meters of the ocean (Spilhaus 1937). While further development of this preliminary instrument revealed it to be rather critical to vibration, the results obtained with it, some of which were reported in the paper cited above, were sufficient to indicate the desirability of further studies and development along these lines. Abrupt changes in the vertical temperature distribution with very small changes in horizontal distance together with extremely complex temperature structure in the vertical were observed in the surface layers....