The six galleasses represented a new type, a link between the oared ships of the past and the sailing fleets of the immediate future. They were heavy three-masted ships, with rounded bows, and their upper works built with an inward curve, so that the width across the bulwarks amidships was less than that of the gundeck below. The frames of warships were built on these lines till after Nelson's days. This "tumble home" of the sides, as it was called, was adopted to bring the weight of the broadside guns nearer the centre line of the ship, and so lessen the leverage and strain on her framework. The guns had first been fired over the bulwarks, but at a very early date port-holes were adopted for them. The galleass had a high forecastle and poop, each with its battery of guns, pointing ahead, astern, and on each side. Other guns were mounted on the broadsides in the waist of the ship; and to command the main-deck, in case an enemy's boarders got possession of it, lighter guns were mounted on swivels at the back of the forecastle and on the forepart of the poop. Compared to the low, crowded galley, the galleass was a roomy and much more seaworthy ship. She was generally a slow sailer, but in order to enable her to make some progress, even in calms or against a head wind, and so work with a fleet of galleys, she had a rowers' deck, under her main or gundeck, and on each side twelve or fifteen oars of enormous length, each worked by several men. She had the drawbacks of most compromises. She could not sail as well as the frigate, and her speed with the oar was much less than that of the galley. But the gain was that she could be used as a floating battery, carrying many more guns than the few pieces mounted in the galley's bows. The galleass's guns were high above the water, and the galleys dreaded their plunging fire. Each of Don Juan's six galleasses carried some thirty guns of various calibres, and to defend their high sides against an attack by boarders, their fighting-men were chiefly arquebusiers. In order to fuse the triple fleet of the Allies into one armada, and to avoid the risk of international jealousies, Don Juan proceeded to form his galleys into five squadrons, each made up of ships selected from the three fleets, so that none of these divisions could claim to act only for Rome, or Spain, or Venice. The organization of the Christian armada may be thus summed up in tabular form:--