Charts existed, but the knowledge of the capes and headlands, islands, bays and anchorages, was mostly carried in the pilot’s head.

The galley had evolved out of the Byzantine dromon, or ‘racer’, but for its ancestry one must go back to the days of the Phoenicians and of classical Greece and Rome. A large galley of the Venetian type might be as long as 180 feet, although the Rhodian galleys were usually shorter than this. The beam on such a galley would be only about nineteen feet and the depth of the hold eight feet. Even on an overall length of 180 feet the waterline length would probably be no more than 125 feet, for there was a very long overhang at the bow and a considerable one at the stern. She was a vessel designed for speed and mobility, not for carrying capacity or for weatherliness in anything other than the months of summer. She stepped two, and sometimes three, short masts on which were set triangular lateen sails. These had been known to the Romans and had then disappeared from the sea until brought back again by the Arabs who had preserved the usage of them in the Red Sea and in their monsoon trade with India. The lateen was, until the invention of the gaff rig centuries later, the most efficient sail for almost all purposes. It required little manpower to hoist and set, it was quite efficient for windward work while, with the two main lateens boomed out on opposing sides (‘goose-winged’), it provided a well-balanced sail area for downhill work. The other principal vessel to be found upon the sea at this time—and the one upon which the Knights preyed—was the ‘round ship’ or merchantman.

She, like the galley, could also trace her origins back to the Phoenicians whose merchantmen had been known to them as a ‘Gaulos’ or ‘Tub’ from their shape—something like a half walnut. These of course were designed for carrying capacity above all, and were dependent almost entirely upon sails for their motive power. Beamy, high-sided, and driven by squaresails or a combination of squaresails and lateens, they were better sea-boats than the galleys, but were cumbersome to handle and, unless flying with a fair breeze astern, were no match for the galleys. Half way between these two types of vessel came the galleass, a cargo-carrying ship mainly dependent upon sail but which also had oar-power and, at a later date, was capable of mounting a fair weight of guns. It was a combination of the round ship and the galleass, evolved into a thoroughly seaworthy vessel in northern waters by English, Danes and Dutch, that was ultimately to supersede all others. For the moment though, during the centuries that the Knights were in Rhodes, the galley was the most powerful ship upon the sea. Its design was so good that, even though somewhat discredited after the seventeenth century, the galley would still be active upon these tideless waters until the nineteenth century when the advent of steam as a propulsion power changed the face of all the seas and oceans.

Quite apart from the lead and line for determining depths when in pilotage waters, the galley masters and their navigators had portulans or pilotage books. Their principal navigational instrument was the compass. These were in common use by the fourteenth century, and references to the magnetic compass occur as early as the twelfth century. In view of the fact that the original establishment of the Hospital derived from the merchants of Amalfi it is interesting to note that it was often claimed that the compass itself had originated there. The fact is that the Amalfitans almost certainly learned about the compass during their trade with the East, and that it was known to the Arabs a long time before it became generally used by Europeans. It is possible, however, that it was the Amalfitans who first anchored the compass needle to a marked card so as to make compass reading considerably easier. Prior to this the early method of using the magnetised needle was to rub it on a lodestone, thus magnetising the metal, and then to pierce a reed or a thin sliver of wood with the needle and float it in a bowl of water, when the needle would turn and point to magnetic north. Such a system was of course of little use unless the weather was fair, for if the vessel was rolling or heeled to a wind it was almost impossible to keep the bowl sufficiently still. Quite apart from the compass, the pilots had their knowledge of the stars to guide them at night. Polaris the North Star had been used as a navigational aid since the days of Homer—and probably long before.

When the galleys were out in company, say four of them at a time, tactics were very similar to those adopted by the cavalry, the ships advancing in line abreast against the enemy. Quite often, however, the galleys went out in twos, and they then used tactics very similar to those of the hunting lion and lioness. Hearing that a merchantman was bound through a particular channel the fastest galley would endeavour to get behind her, leaving her ‘mate’ lurking behind a suitable point or headland. The galley would then drive the fleeting merchantman in the required direction. At the very moment when it might have seemed that she had the legs on her pursuer and was about to make good her escape, the merchantman would find her way barred by the second galley sliding out from concealment to bar her course.

At the last stages of the run-in, or when just about to board the enemy, the Knights had another trick up their sleeves. This was Greek fire, or ‘wild fire’ as it was sometimes called.