demand in the East, skirted the Arabian and Persian coasts, taking advantage B.C. — of such prominent head-lands as enabled them to steer direct without following the windings of the shore, and thus reached the Indian coast near the mouths of the Indus. How far they afterwards proceeded south is not known; but as there was no obstacle in the way, and some of the most prized products of the country lay in that direction, it is to be presumed that, instead of confining themselves to a few isolated spots, they formed a general acquaintance with the whole sea-bord. To secure the command of tliis lucrative trade, the Egyptian kings maintained a large fleet at sea, which, while it kept down piracy, deterred other nations from entering into competition with them. The nation which could have done so with most effect was Persia, which possessed the obvious and very im})ortant advantage of a far shorter sea passage. From the Persian Gulf they could have reached India in about half the time which the Egyptians must have taken. The Persians, however, had long an aversion to maritime enter- Tiie Persians prise — an aversion so great, that they are said to have erected barriers across the maritime Tigris and Euphrates for the purpose of rendering it impossible. Be this as it may, it seems established that the Indian produce which they obtained for their own use, or the supply of adjacent countries, came mostly overland by the caravans. Another cause of the supineness of the Persians in regard to mari- time intercom'se with India, may be found in the erroneous ideas generally entertained respecting the proper limits of the Caspian Sea on the north, and its relative position to the Black Sea. The Caspian was somewhat unaccount- ably imagined to be a branch of the great Northern Ocean, and it was believed that by means of it a channel of communication might be opened up with Europe, which might thus be made to receive the products of India by a far Krrorein shorter route than the Indian Ocean, and consequently at a far cheaper rate than they could be furnished by the Egyptians. Ideas of this kind seem to have weighed particularly with some of Alexander's successors in the East. Seleucus Nicator, the first and one of the ablest of them, is even said to have contemplated a canal which would have joined the Caspian and Black Seas, and thereby secured a monopoly of European and Indian traffic.
After the Romans conquered Egypt and converted it into a province, in B.C. 30, the channels of traffic with the East continued unchanged, while its amount was enormously increased both by land and sea. By the latter, in particular, the traffic received an impulse unfelt before, when a navigator of the name of Hippalus conceived the idea of cutting off" nearly a half of the voyage between HippaUis the. Red Sea and India, by abandoning the timid track ])ursued along the rlnugoof iutervenins: shores, and steering boldlv far out of sioht of land through the very middle of the ocean. The plan seems so natural, and the considerations which suggested it so obvious, that one finds some difficulty in recognizing Hippalus as the inventor, or in giving him much credit for the invention. He
