Gauger

from The Collaborative International Dictionary of English v.0.48

Gauger \Gau"ger\, n.
   One who gauges; an officer whose business it is to ascertain
   the contents of casks.
   [1913 Webster]

from Bouvier's Law Dictionary, Revised 6th Ed (1856)

GAUGER. An officer appointed to examine all tuns, pipes, hogsheads, barrels, 
and tierces of wine, oil, and other liquids, and to give them a mark of 
allowance, as containing lawful measure.

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