As indicated before, the Romans took great care of and interest in their own empire but they did not show much interest in reaching out beyond its borders, preferring instead to leave that to middlemen. Greeks, especially, were left to deal with peoples to the east. Sometime in the early part of the first century A.D., for example, a Greek merchant of whom nothing is known except his name, Hippalus, is said to have become familiar with the lands bordering the Arabian Sea and also with the seasons’ prevailing winds of that area. One summer he put his knowledge to the test and sailed quite easily from the tip of the Arabian Peninsula to the mouth of the Indus River; then in the winter, when the wind direction changed, he returned from India to Arabia. After several such voyages, word of this strategy spread and helped to increase trade between the Roman Empire and India.
Hippalus and his achievement are known only from another anonymous Greek’s work, the Periplus Maris Erythraei, or “Sailing around the Erythraean Sea,” a navigator’s guide to the coasts of the lands that border the Arabian Sea and Indian Ocean—Africa, Arabia, and India. Dated to somewhere between A.D. 50 and 90, it is a remarkable document, detailing not only the natural features of the coasts but also the main ports and trading stations and their exports and imports. It was clearly a guide for merchants, but it also included a great deal of basic geographical information, as exemplified by this description of the extremely strong tidal flow of the Mahi River along the west central coast of India:
So great indeed is the violence with which the sea comes in at the new moon, especially during the nightly flow of the tide, that, while at the commencement of its advance, when the sea is calm, a sound like the shouting of an army far away reaches the ears of those who dwell about the estuary, and shortly afterwards the sea itself with a rushing noise comes sweeping over the shallows.
This Periplus, however, is notable for another feature. Although the author of the coastal guide seems to have firsthand knowledge only down to about 500 miles northwest of the tip of the Indian peninsula, he mentions reports of points much farther on—not only along the eastern coast of India but even eastward to what was most likely the peninsula of Malay, and still farther. He reports a distant land where “there is a great inland city called Thina, from which raw silk and silk yarn and silk cloth are brought overland.” Although scholars cannot agree on exactly what city he was referring to, they tend to agree that the people producing the silk were Chinese, thus making this one of the earliest references to the Chinese in Western accounts.
Silk itself was by no means an unknown product in the West at this time—late first century A.D.—at least in Rome. In the first century B.C., Roman historians reported, silk was used to make awnings for Julius Caesar’s ceremonies and for Cleopatra’s dresses. Clearly, though, it was a luxury reserved for the most powerful. Just as clearly, even the Romans who knew about silk remained uncertain about its source as they obtained it through middlemen at the fringes of their empire. It would not be long, though, before Rome would deal directly with China and Asia and discover a continent with its own distinguished history and attainments in the field of exploration.