Tronage

from The Collaborative International Dictionary of English v.0.48

Tronage \Tron"age\, n. [From {Trone} a steelyard.]
   A toll or duty paid for weighing wool; also, the act of
   weighing wool. [Obs.] --Nares.
   [1913 Webster]

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

TRONAGE, Eng. law. A customary duty or toll for weighing wool, so called 
because it was weighed by a common trona, or beam. Fleta, lib. 2, c. 12.

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