destabilize or capsize them. The Byzantine navy, the largest Mediterranean war fleet throughout most of the Early Middle Ages, employed crescent formations with the flagship in the center and the heavier ships at the horns of the formation, in order to turn the enemy's flanks. Similar tactics are believed to have been employed by the Arab fleets they frequently fought from the 7th century onward. The Byzantines were the first to employ Greek fire, a highly effective incendiary liquid, as a naval weapon. It could be fired through a metal tube, or siphon, mounted in the bows, similar to a modern flame thrower. Greek fire was similar to napalm and was a key to several major Byzantine victories. By 835, the weapon had spread to the Arabs, who equipped harraqas, "fireships", with it. The initial stages in naval battles was an exchanges of missiles, ranging from combustible projectiles to arrows, caltrops, and javelins. The aim was not to sink ships, but to deplete the ranks of the enemy crews before the boarding commenced, which decided the outcome. Once the enemy strength was judged to have been reduced sufficiently, the fleets closed in, the ships grappled each other, and the marines and upper bank oarsmen boarded the enemy vessel and engaged in hand-to-hand combat. Byzantine dromons had pavesades, racks along the railings, on which marines could hang their shields, providing protection to the deck crew. Larger ships also had wooden castles on either side between the masts, which allowed archers to shoot from an elevated firing position. Later medieval navies continued to use similar tactics, with the line abreast formation as standard. As galleys were intended to be fought from the bows, and were at their weakest along the sides, especially in the middle. The crescent formation employed by the Byzantines continued to be used throughout the Middle Ages. It would allow the wings of the fleet to crash their bows straight into the sides of the enemy ships at the edge of the formation. Roger of Lauria (c. 1245–1305) was a successful medieval naval tactician who fought for the Aragon navy against French Angevin fleets in the War of the Sicilian Vespers. At the Battle of Malta in July 1283, he lured out Angevin galleys that were beached stern-first by openly challenging them. Attacking them in a strong defensive position head-on would have been very dangerous since it offered good