Lateen sail

A lateen (from French latine, meaning "Latin") or latin-rig is a triangular sail set on a long yard mounted at an angle on the mast, and running in a fore-and-aft direction.

Dating back to Roman navigation, the lateen became the favourite sail of the Age of Discovery, mainly because it allows a boat to tack "against the wind." It is common in the Mediterranean, the upper Nile River, and the northwestern parts of the Indian Ocean, where it is the standard rig for feluccas and dhows. The lateen is used today in a slightly different form on small recreational boats like the Sailfish and Sunfish, but is still used as a working rig by coastal fishermen in the Mediterranean.

The earliest fore-and-aft rig was the spritsail, appearing in the 2nd century BC in the Aegean Sea on small Greek craft. One theory is that the lateen sail originated during the early Roman empire in the Mediterranean Sea. It evolved out of the dominant square rig by setting the sails more fore-and-aft – along the line of the keel – rather than athwartship, while tailoring the luff and leech. The theory of Roman origin for lateen was begun with Lynn White and followed by Lionel Casson but was contested by John M. Hobson. John M. Hobson offered many evidences to prove that the theory of Roman origin is wrong

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