But the people of Alexandria having become insolent in their prosperity, HADRIAN was led to encourage the route through Palmyra, which was the most direct road to India. Even in the 2nd century A.D. the trade between Rome and India through Palmyra must have been considerable, for it drew the attention of the Chinese. Their annals speak of it as carried on principally by sea; they mention Roman merchants in relations of commerce with and visiting Burmah, Tonquin, and Cochin China, and they have preserved the memory of an embassy from the Roman emperor, which in the year A.D. 166 was received by the Chinese sovereign. Arab or native vessels appear to have brought the produce of India up the Persian Gulf to the mouth of the Euphrates. At Teredon they discharged their cargoes, and the merchandise was then carried to Vologesia by camels; at this place the merchants of Palmyra took it up and it was here exchanged for the produce of Europe. Even as late as the 5th century, ships from India and China are mentioned lying at Hira on the Euphrates, a little to the south of Babylon. Through the influence of this trade Palmyra grew rapidly into wealth and power until the widow of GALBERIUS threw off her allegiance to Rome. This led to the destruction of the city by AURELIAN, A.D. 275, which put an end to the Roman trade with India through the Persian Gulf. The Alexandrian trade with India fell off about the same time, and the barbarians occupied Coptos, the port of embarkation for India, about A.D. 279.