Ab urbe condita

Titus Livius (Livy)

Livy. History of Rome, Volumes 1-2. Roberts, Canon, Rev, translator. London, New York: J. M. Dent and Sons; E. P. Dutton and Co., 1912.

They accordingly packed up their goods and removed to Rome.

They had got as far as the Janiculum when a hovering eagle swooped gently down and took off his cap as he was sitting by his wife's side in the carriage, then circling round the vehicle with loud cries, as though commissioned by heaven for this service, replaced it carefully upon his head and soared away. It is said that Tanaquil, who, like most Etruscans, was expert in interpreting celestial prodigies, was delighted at the omen.