POR1 recently described the interesting discovery of a “solar lake” on the shores of the Gulf of Aqaba, Red Sea, 20 km south of Elat. Such a solar lake is characterized by a very sharp increase of salinity, and, consequently, of density with depth, with the result that a layer of high static stability is produced near the bottom. The high static stability of the layer prevents the formation of turbulence or at least reduces the level of turbulence, thus eliminating, fully or partly, an effective agency for heat conduction. It is therefore expected that much of the solar radiation absorbed in the stable layer will be “trapped” there and may become an energy source. As Por points out: “Solar lakes … have a considerable future in relation to desalination plants and low energy turbines in areas in which both energy resources and fresh water are scarce.” (As far as I know, it was Dr R. Bloch, Negev Institute of Arid Zone Research, Beersheba, Israel, who first recognized the potentialities of solar lakes for the exploitation of solar energy.)