In Italy the purely warlike ship had become so obsolete that, in the opinion of some authorities, it was not till about the middle of the ninth century that these began to be built, at any rate as regards that great maritime power, Venice. She had been too concerned with the production and exchange of wealth to centre her attention on any species of ship other than those which would carry freights. But so many defeats had she endured at the hands of the Saracens and pirates that ships specially suitable for combat had, from the year 841, to be built. The Saracens hailed from Arabia, and it is notable that at that time the Arabian sailors who used to sail across the Indian Ocean were far and away the most scientific navigators in the whole world, many of their Arabic terms still surviving in nautical terminology to this day. Indeed, the modern mariner who relies so much on nautical instruments scarcely realises how much he owes to these early seamen. Just as the Cilicians and others had in olden times harassed the shores of the Mediterranean, so now the Saracens made frequent incursions into Sardinia, Corsica, Sicily, as well as intercepting the ships of the Adriatic. Let us remember that both in the north and south of Europe the sailing seasons for century after century were limited to that period which is roughly indicated between the months of April and the end of September. Therefore the pirate knew that if he confined his attentions to that period and within certain sea-areas, he would be able to encompass practically the whole of the world’s sea-borne trade. These sailing periods were no arbitrary arrangement: they were part of the maritime legislation, and only the most daring and, at the same time, most lawless merchant skippers ventured forth in the off-season. Realising that the mariner had in any lengthy voyage to contend not merely with bad weather but probably with pirates, the merchant pilots were instructed to know how to avoid them. For instance, their main object should be to make the merchant ship as little conspicuous on the horizon as possible. Thus, after getting clear of the land, the white sail should be lowered and a black one hoisted instead. They were warned that it was especially risky to change sail at break of day when the rising sun might make this action easily observable. A man was to be sent aloft to scan the sea, looking for these rovers and keep a good look out. That black sail was called the “wolf,” because it had the colour and cunning of such an animal. At night, too, similar precautions were employed against any danger of piratical attack, strict silence being absolutely enforced, so that the boatswain was not even allowed to use his whistle, nor the ship’s bell to be sounded. Every one knows how easily a sound carries on the sea, especially by night, so the utmost care was to be exercised lest a pirate hovering about might have the rich merchant ship’s presence betrayed to her avaricious ears.