Oar

As they lean back, towards the vessel's bow, the blade of their oars pivots in the oarlock, and the end in the water moves towards the stern, providing forward thrust.

It is common for an oar propelled vessel to also have the option to be powered by sail, both in antiquity (for instance the galley) and more recently.

Wooden oars, with canoe-shaped pottery, dating from 5000–4500 BC have been discovered in a Hemudu culture site at Yuyao, Zhejiang, in modern China.

[1][2] In 1999, an oar measuring 63.4 cm (2 ft) in length, dating from 4000 BC, was unearthed in Ishikawa Prefecture, Japan.

Oars usually have a handle about 150mm long, which may be a material sleeve or alternatively an ovoid shape carved to fit the hands.

The oar is fixed in the oarlock, the rower pulls on the handle, and the blade moves in the opposite direction to propel the boat.

According to Callixenus, as cited by Athenaeus, in the great ship of Ptolemy the oars of the upper tier were over 50 feet (15 m) in length with handles leaded so as to equalize the weight inboard and outboard.

The sport of competitive rowing has developed a tradition of using an oar as a memento of significant race wins.

A 'trophy oar' is not presented at the end of the race as a more familiar precious metal cup might be, but rather given by the club, school or university that the winning crew or rower represented.

The most common format has the coat of arms or crest of the club or school positioned in the centre, with the crew names and the race details arranged around this.

The members of the Family Regalecidae, elongated deep-sea fishes, are called oarfish because their body shape is similar to that of an oar.

[7] The hawksbill turtle's genus of Eretmochelys is derived from the Greek root eretmo, which roughly translates to oar.