Figure 14. W. F. Ewald’s and K. Grein’s photometer. Left: view of the apparatus. Right (from top to bottom): messenger container; removable photographic plates; removable filters. This instrument was designed by Wolfgang F. Ewald with the aid of Klaus Green. It was first tested off Capri and put to the definitive tests off Monaco in up to 500 meters.
Photo Category: Oceanography - Historical instruments