Supersonic Sounding Instruments and Methods

A brief history of the development of echo sounders is given. The distinguishing features of various basic types of sounders are discussed, together with the elements of echo sounder operation: The inherent limitations of echo sounding are pointed out with certain supporting data to enable some of the limitations to be determined on a quantitative basis. The use of echo sounders over firm sand bottoms and over soft mud bottoms is discussed, and factual data are introduced to show the “ average” error to be expected in repeated soundings of the same profile. A comparison is made between sound1ngs of a selected profile as obtained by echo sounders and by lead line, and the comparative results from the two methods are given in considerable detail.