Suetonius, Life of Vespasian:
“Vespasian possessed an abundant store of wit, though it was of a scurrilous and dirty sort, and he made little effort to refrain from obscene language. Yet, some of his finest raillery survives, among which is this story. One day, Vespasian was admonished by a Certain Mestrius Florus that he should say plaustra and not plostra. The next day, Vespasian greeted Florus as Flaurus. He was once overcome by a certain woman who claimed to be dying of love for him. When he had given her four hundred sesterces for sleeping with him, the accountant asked how he would like the sum entered in the books. Vespasian responded, ‘For making love so zealously with the emperor.'”
erat enim dicacitatis plurimae, etsi scurrilis et sordidae, ut ne praetextatis quidem verbis abstineret. Et tamen nonnulla eius facetissima exstant, in quibus et haec. Mestrium Florum consularem, admonitus ab eo plaustra potius quam plostra dicenda, postero die Flaurum salutavit. Expugnatus autem a quadam, quasi amore suo deperiret, cum perductae pro concubitu sestertia quadringenta donasset, admonente dispensatore, quem ad modum summam rationibus vellet inferri, “Vespasiano,” inquit, “adamato”.