Figure 11. W. F. Ewald's photometer, messenger model, at the end of operation.Invented by Wolfgang F. Ewald about 1910 to fix some of the problems of theprevious model. First tested about 1910 off the coast of Scotland. Other tests were then made
4/4/2019 1:50:12 PM
Photographer: P. Roggero
Credit: Oceanographic Museum of Monaco
Subject: Oceanography
Subject: Historical instruments