Besides Petra and Palmyra, the cities of Sardes, Babylon, Gerrha, Damascus, and Susa were all peculiarly well situated for carrying on a large inland commerce; and these places, with Thebes and Memphis, were as famous in their day as great commercial entrepôts, as London, Liverpool, Glasgow, New York, Marseilles, or Hamburg are in our own time. At the period to which we now refer, Arabia, including Asia Minor, and the northern portion of Africa, may be said to have been divided into four great caravan routes, with numerous tributaries. The first embraced the traffic between Egypt and Palestine; the second extended from the coast of Syria, including the trade of Phœnicia with Babylon and Assyria, through the plains of Mesopotamia to the north, and along the shores of the Red Sea to the south; the third traversed Asia Minor to the north; and the fourth route lay through Africa, with Thebes as its centre, and the Nile and ports of the Red Sea as its outlets. [Sidenote: Eastern.] But Arabia, of all countries, was the most frequented by caravans. From Petra, where vast numbers of travellers met, an important and lucrative trade was carried on with Yemen and the fertile districts of the south, especially with that portion of the great peninsula which lies between the Persian and Arabian Gulfs, where it is washed by the Indian Ocean. In a commercial point of view, Yemen was one of the most important countries through which the caravans passed; not merely on account of its own productions, but from being at a very early period a depôt of Indian as well as of Ethiopian merchandise, and the principal mart in those days for spices, perfumes, and especially frankincense. [Sidenote: Southern.] That branch of the caravan trade between Palestine and Egypt, mentioned in the Mosaic records, is also noticed by Herodotus, who states that the transport of Egyptian and Assyrian wares was the first business carried on by the Phœnicians.[205] Tyre also sent large quantities of wine into Egypt, receiving in exchange the “fine cotton and embroidered work” of which Ezekiel speaks.[206] In somewhat later times, Babylon became one of the principal places to which the Phœnicians directed their attention, and traces are still to be seen of the cities which marked alike the course and the extent of this inland traffic. [Sidenote: Northern.] In considering the account in Ezekiel, we have already noticed the trade between Tyre and the nations on the Black Sea such as “Tubal and Meshech”: where a portion of the trade was probably by caravans, especially that from “Togarmah” (Armenia), whence the Tyrians obtained “horses of noble and common breeds, and mules for their wares.” The same is probably true of the vessels of copper imported thence into Tyre, the same range of mountains (the Taurus) affording at present similar productions. [Sidenote: The character, size, and discipline of the caravans.]