From Alexandria the course of trade with the East seems to have at first passed to Arsinoe, the present Suez, but the difficulties and dangers of the navigation of the northern extremity of the Red Sea, led to the formation by Ptolemy Philadelphus, on its western shores, of the harbour of Myos Hormus, as well as the more important roadstead of Berenice, whereby direct communication with the outer ocean was greatly facilitated, and due advantage could be taken of the prevailing winds within the Straits. Goods were conveyed by the Nile to Coptos, and were thence transported over land by caravans to Myos Hormus, or Berenice. To render these routes more easy and endurable during many days’ march through torrid deserts, Philadelphus sought out the needful springs, and established caravanserais at these necessary halting places. Pliny[228] and the Itinerary of Antonine[229] give a list of them; and it is worthy of record, that Belzoni recognized traces of many of these routes when he visited that country.[230] [Sidenote: Time of the departure of the fleets.] From both Myos Hormus and Berenice the fleets appear to have sailed in the month of September for Arabia, as well as for various ports on the coast of Africa; and in July for India. These periods, from the course of the prevailing winds, were the best adapted for proceeding upon such voyages. In the first instance, clearing, as we may presume they would do, the Straits in the month of November, they would probably fall in with a wind during that month which would carry them down the coast of Africa, and enable them to return with equal facility in the course of the following months of May and June. By sailing in July from Berenice, or Myos Hormus, they would reach Bab-el-Mandeb before the 1st of September, and would thus have a fair wind for nearly three months. Thence they could easily reach the shores of Malabar, even by adhering to an almost strictly coasting route, in the forty days, in which, as we learn from Pliny, that portion of the voyage was usually performed.[231] [Sidenote: Residence of the merchants, and course of trade from Alexandria to the East.] The merchants who carried on these important trades, both under the Ptolemies and the Romans, resided chiefly, if not altogether, at Alexandria; and though the Ptolemies, for their own interest, were willing to extend, as far as possible, mercantile privileges, the law of Egypt still required (as in the case of Naucratis) the employment of an Alexandrian factor for the transaction of the merchant’s business: a custom which in a great measure accounts for the immense wealth of Alexandria.