The bale crosses the bridge if the pan reads twenty ounces exactly. The pieces in the drawer have no weight stamped on them: the excise man knew them by heart and has been dead two years.
Hang up whichever you like and read the steelyard. That alone is enough to work out what each one weighs.
The bylaw is plain: twenty ounces exactly and not a dram more. In the drawer lie five unmarked iron pieces, because the old excise man kept their weights in his head and told nobody. The steelyard does not lie: hang, read and write it down.
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