A gubernaculum in classical references describes a ship's rudder or steering oar. Gubernaculum, like cornucopia, is really a Latin word. The English word government is related to it. The Old English word governail and the Scots word gouernaill are both derived from it.
The ancient rudder's different parts were distinguished by the following names: ansa, the handle; clavus, the shaft; pinna, the blade. The famous ship Tessarakonteres or Forty is said to have had four rudders. In the Bible, Paul's ship, which was shipwrecked on Malta, had its rudders (plural) cut loose.
Various gods such as Tritons and Venus have been shown with a gubernaculum. It is most associated with Fortuna since, along with the cornucopia, it is an item that she is often depicted as holding. The corresponding Greek god Tyche is also regularly shown with a gubernaculum. There are abundant depictions of Fortuna holding the gubernaculum on coins, in paintings, on altars and statues or statuettes.
Fortuna is depicted on around 1000 different Roman coins usually holding a gubernaculum.
A sandstone statuette of Fortuna, the Roman god of luck, fate, fortune was found at Castlecary and can now be found at the Hunterian Museum in Glasgow, Scotland.
In mythology the rudder, which the goddess can steer, represents control of the changeable fortunes of life. Plato used the metaphor of turning the Ship of State with a rudder. In the Biblical book of James, the author compares the tongue with a ship's rudder which, though physically small, makes great boasts.