In an effort to economically empower the Roman state and return to her the former glory, Roman emperor Vespasian (9-79) introduced a tax on everything that came to his mind.
Among many things, the citizens of Rome had to pay tax even for using public urinals.
When Vespasian's son Titus objected his father's decision on this kind of tax, considering it unworthy for any man, Vespasian grabbed a handful of coins, brought them under his son’s nose and uttered the famous phrase: "No olet" ("They don’t stink!")
In remembrance of this tax, public toilets in France are even today called "Vespasiennes”.
