Sigsbee Sounding Machine - invented by Charles D. Sigsbee and modified from
Thomson Sounding Machine. Basic design of ocean sounding instruments stayed the
same for the next 50 years. Here the sounding machine is used to set a
Pillsbury current meter at a known depth. In: "The Gulf Stream", by John
Elliott Pillsbury, 1891. Call Number GC296.G9 P54 1891.