Their first attempt was made from the port of Otranto, where, after a preparation of two years, they had collected a fleet of one hundred and fifty vessels, and thirty thousand men, including one thousand five hundred Norman knights. But this expedition proved a calamitous failure. The Normans were no longer the experienced or adventurous mariners, who had explored unknown oceans, from Greenland to Africa; hence, in a great storm they encountered at the mouth of the Adriatic, many of their ships were shattered, while others were dashed on shore and became hopeless wrecks. Besides, a new, and a naval, enemy had arisen in the Venetians, who, at the solicitations and promises of the Byzantine court, were ready enough to aid in the overthrow of the hated Normans, and, with a view of tempting commercial advantages for themselves, to assist in defending the capital of the East. And so it befell, that what the storm had spared of the Norman fleet, the Venetians and Greek fire destroyed; add to which, the Greek populations, sallying from their towns along the southern shores of Italy, carried slaughter and dismay to the tents of the chiefs of the Norman invaders. But three years afterwards, their indefatigable duke (Robert Guiscard) resumed the design of his eastern conquests; preferring, on this occasion, as the season was far advanced, the harbour of Brundusium to the open road of Otranto for the assembling of his fleet of one hundred and twenty vessels. However, in the interval Alexius, the emperor, had assiduously laboured to restore the naval forces of the empire, obtaining at the same time, at an exorbitant price, the aid from the republic of Venice of thirty-six transports, fourteen galleys, and nine galiots, or ships of unusual strength and magnitude. The goods and merchandise of the rivals of the Venetians at Amalfi were taxed to raise the required sum; and by granting special privileges, such as the licence or monopoly of trade in the port of Constantinople, with the gift of many shops and houses, Alexius propitiated the good will of the Venetian merchants. But this expedition was so far successful, that the Normans captured and destroyed many of the vessels of the combined fleets; it failed, however, to take Constantinople, against which the Normans relinquished any attempts worthy of notice after the death in the following year of their prince, Guiscard. [Sidenote: Rise of Venice.] [Sidenote: A.D. 452.]