Titus complained of the tax which Vespasian had imposed on the contents of the city urinals. Vespasian handed… — Suetonius

Titus complained of the tax which Vespasian had imposed on the contents of the city urinals. Vespasian handed him a coin which had been part of the first day's proceeds: "Does it smell bad?" he asked. And when Titus said "No" he went on: "Yet it comes from urine."

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