Alexander's invasion was directed against Northern India, or the Panjab; in those days a populous and highly cultivated country; now the seat of the Seiks and Mahrattas; and then, as now, inhabited by warlike races. He crossed the Indus at Taxila (Attock,) passed the Hydaspes (Behut or Chelum,) and, availing himself of the quarrels between the Indian princes, defeated the king, Porus. He then proceeded across the Acesines (Jenaub) and Hydraotes (Rauvee). The eastern verge reached in this expedition was the river Hyphasis (Beyah;) here, having already proceeded half way to the Ganges, the conqueror was, by a mutiny in his army, compelled to retreat. His return was through the country of the Malli (Multan) as far as the Hydaspes, when the majority of his troops took ship, and were floated along that stream into the Acesines, and from thence into the Indus, which they followed down to its mouth. RENNEL, _Memoir of a Map of Hindostan_. London, 1793, (3d. edit.) and ST. CROIX, _Examen_, etc. (see p. 216.) furnish all the necessary historical and geographical explanations relative to the Persian and Indian campaigns of Alexander. 28. Although Alexander was obliged to give up the project of conquering India, yet the connection between Europe and the east, which has continued from that time, was the work of his hands. While the communication on land was secured by the establishment of various settlements, the communication by sea was opened by the voyage of his admiral, Nearchus, from the Indus to the Euphrates. In the mean time Alexander himself proceeded to Persis and Babylon, across the desert, and the unexplored provinces of Gedrosia and Carmania. Nearchus's voyage (our knowledge of which is derived from his own journal, preserved in Arrian's _Indica_) lasted from the beginning of October, 326, to the end of February, 325: nearly the same time was occupied in the almost incredible land march of the king. VINCENT, _The Voyage of Nearchus from the Indus to the Euphrates_. London, 1797, 4to. Exhibiting the most learned researches, and illustrated with excellent charts. 29. After the abandonment of India, the whole circuit of Alexander's conquests was precisely that of the former Persian empire; his later projects were probably directed against Arabia alone. However easy it had been to make these conquests, it was a more difficult task to retain them; for Macedonia, exhausted by continual levies of men, could not furnish efficient garrisons. Alexander removed this difficulty, by protecting the conquered from oppression; by showing proper respect to their religion; by leaving the civil government in the hands of the native rulers who had hitherto possessed it; and by confiding to Macedonians the command only of the garrisons left in the chief places, and in the newly established colonies. To alter as little as possible in the internal organization of countries was his fundamental principle.