the fall of the Græco-Bactrian kingdom the Greeks had to deal with both Sakas and Parthians. It would seem that the latter were alternately friends and foes. This intercourse possibly accounts for the Parthian characteristics found on the early Saka coins of India.[37] The Sakas were driven towards the Pamirs and the Tien-shan. One branch of them fled to Zungaria, while the majority remained in Hexapolis and intermixed with the Uīghūrs, who had been for a long period masters of that country. A third branch turned their steps towards the upper valleys of the Yarkand Darya. Some of these fugitives established themselves in the little Iranian States of Serikūl and Shugnān, where appreciable traces of their language still survive.[38] Others crossed the Karakorum, and invaded the north-east of India. At this epoch the Chinese obtained a glimpse of the position of Western Asia through the medium of prisoners taken from the Hiung-nu. From them they learned that the Yué-Chi had suffered defeat at the hands of the Huns, and been compelled to migrate far from their ancient abode. They had, however, become very powerful in Bactria and Transoxiana, and had conquered Ta-hia (Khorāsān), establishing themselves finally there in spite of the Parthian resistance. The Emperor Wu-ti eagerly desired an alliance with the Yué-Chi against their common enemy the Hiung-nu. With this view he sent his general Chang-Kien on an embassy to the prince, accompanied by a suite of a hundred attendants. The envoy, however, had the misfortune to fall into the hands of the Huns while traversing their territory, and escaped only after a ten years’ imprisonment. On joining the Yué-Chi, he found them employed in driving the Sakas out of Soghdiana. He accompanied them on a victorious expedition, and then returned to China, with two followers, sole survivors of his cortege. The emperor expressed his appreciation of the intelligence brought by Chang-Kien regarding Central Asian events, by elevating him to an important post. These events led to the establishment of direct commercial intercourse between China and the West, which, however, the Huns did their utmost to interrupt. A collation of the Chinese annals, the classic authors, and the coins which have come down to us, would render it tolerably certain that the Greeks lost their hold on Soghdiana in B.C. 163; that a little later they were deprived of Bactria by the Sakas, and of Margiana by the Parthians. From this period their dominion was limited to the southern slopes of the Indian Caucasus. That the Græco-Bactrian Empire had attained a high degree of natural civilisation, and, indeed, of artistic culture, is evidenced by the purity of design and the excellence of workmanship displayed by the later coins.