Persia at her greatest maintained a considerable overland trade with India, and Indian tribute formed a large part of her revenues. All Afghanistan was Persian; all Baluchistan, and the Indian frontier to the Indus. The underlying Persian element is strong in all these regions still, the dominant language of the country, the speech of the people, whether Baluch or Pathan, is of Persian stock, whilst the polite tongue of Court officials, if not the Persian of Tehran or Shiraz, is at least an imitation of it. It is hardly strange that the Greek language should have absolutely disappeared. We have the statement of Seneca (referred to by Bellew in his _Inquiry_) that the Greek language was spoken in the Indus valley as late as the middle of the first century after Christ; "if indeed it did not continue to be the colloquial in some parts of the valley to a considerably later period." As this is nearly two centuries after the overthrow of Greek dominion in Afghanistan, it at least indicates that the Greek settlements established four centuries earlier must have continued to exist, and to be reinforced by Greek women (for children speak their mother's tongue) to a comparatively late period; and that the triumph of the Jat over the Greek did not by any means efface the influence of the Greek in India for centuries after it occurred. It is probable that when the importation of Greek women (who were often employed in the households of Indian chiefs and nobles at a time when Greek ladies married Indian Princes) ceased, then the Greek language ceased to exist also. The retinue and followers of Alexander's expedition took the women of the country to wife, and it is not, as is so often supposed, to the results of that expedition so much as to the long existence of Greek colonies and settlements that we must attribute the undoubted influence of Greek art on the early art of India. Thus we have a wide field before us for inquiry into the early history of ethnographical movement in Asia, as it affected the relation between Europe and Afghanistan. Afghanistan (which is a modern political development) has ever held the landward gates of India. We cannot understand India without a study of that wide hinterland (Afghan, Persian, and Baluch) through which the great restless human tide has ever been on the move: now a weeping nation of captives led by tear-sodden routes to a land of exile; now a band of merchants reaching forward to the land of golden promise; or perchance an army of pilgrims marching with their feet treading deep into narrow footways to the shrines of forgotten saints; or perchance an armed host seeking an uncertain fate; a ceaseless, waveless tide, as persistent, as enterprising, and infinitely more complicated in its developments than the process of modern emigration, albeit modern emigration may spread more widely.