Digital Library Search
![Figure 42 ship4244.jpg Figure 42](/sites/default/files/styles/max_1300x1300/https/s3.amazonaws.com/s3-east-testmedia-noaa.woc.noaa.gov/dam/Photos/legacy/pl23_ship4244.jpg?itok=r0yZmr6H)
Description
Figure 42. Hopfgartner and Arzberger sounder, devised by Lieutenant Franz vonHopfgartner of the Austrian Merchant Marine and Moriz Arzberger, a civil engineer, this apparatus used the same principle as aneroid barometers which utilizedthe pressure difference between a wall, isolated or not, and the exterior medium. It was tested in 1876 in the Gulf of Trieste in depths up to 17 meters. (Image credit: Oceanographic Museum of Monaco | Y. Berard)