Lissa (Seven Weeks' War).
The only naval action between ironclads in European waters, fought July 20, 1866, between the Austrian fleet of 7 armoured ships and some obsolete wooden vessels, under Admiral Tegethoff, and the Italian fleet of 10 armour-clads, under Admiral Persano. Tegethoff attacked in wedge formation, with his flagship as the apex, and broke the line of the Italian fleet, which was steaming, line ahead, across his bows. He rammed and sank the Italian flagship, and the rest of the action was a melée in which the Italians were defeated and driven off, with a loss of 3 ships and over 1,000 men. This defeat forced the Italians to raise the siege of Lissa.