Figure 21. Silvertown Company sounder, a device very similar to the Belknap-Sigsbee sounder with one important difference. This sounder had a uniqueballast release method which involved a knife cutting the line holding theballast upon beginning of
4/4/2019 2:12:20 PM
Photographer: Y. Berard
Credit: Oceanographic Museum of Monaco
Subject: Oceanography
Subject: Historical instruments