Figure 56. Pecoul logging sounder, invented in 1849 by Master Mariner Adolphe Pecoul of Marseille. This device was used to measure measure depths while a vessel was underway or to be used as a speed logging device. It was tested in 1850. In spite of favorable reports from numerous ship captain, it was rejected by the Ministry of the Marine and Colonies.
Photo Category: Oceanography - Historical instruments