The components of a commercial fisherman's setline were measured in fathoms.
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The rope called a groundline, used to form the main line of a setline, was usually provided in bundles of 300 fathoms.
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Especially in Pacific coast fisheries the setline was composed of units called skates, each consisting of several hundred fathoms of groundline, with gangions and hooks attached.
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Trawl: a long fishing line with many shorter lines and hooks attached to it (usually suspended between buoys)