Good afternoon, Daniel! A xebec is not a galley; oars were used rarely—only during maneuvers. Consequently, xebecs were not built with dedicated rowing benches, as these would have been useless most of the time and would have caused significant obstruction.
The rowers worked standing up, with one men to an oar on small merchant vessels, and sometimes two men if the ship was large and heavily armed.
I have come across at least one image of a Mediterranean xebec from that era showing rowers standing at their oars. It is interesting that the stern platform has been removed from the ship.
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During maneuvers on xebecs, the rowers faced the bow of the ship. Interestingly, the rowers on the pilot boat towing the xebec also face forward so they can see where to maneuver. The vessel is likely heading toward a cargo berth with a particularly complex navigable channel.
The image shows a single rower at each oar. For two people, the oars featured special handles, as shown in the picture below.
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