The Indus has several tributaries. In foaming waterfalls and roaring rapids they rush down from the mountains to meet their lord. The largest of them is called the Sutlej, and the lowlands through which it flows are called the Punjab, a Persian word signifying "five waters." The Indus has thirteen mouths scattered along 150 miles of coast, and the whole river is 2000 miles long, or somewhat longer than the Danube. In the month of July, 325 years before the birth of Christ, Aristotle's pupil, Alexander, King of Macedonia, floated down the Indus with a fleet of newly built ships and reached Pattala, where the arms of the delta diverge. He found the town deserted, for the inhabitants had fled inland, so he sent light troops after them to tell them that they might return in peace to their homes. A fortress was erected at the town, and several wharves on the river bank. He turned over great schemes in his mind. Had he not at twenty years of age taken over the government of the little country of Macedonia, and subdued the people of Thrace, Illyria, and Greece? Had he not led his troops over the Hellespont, defeated the Persians, and conquered the countries of Asia Minor, Lycia, Cappadocia, and Phrygia, where with a blow of his sword he had severed the Gordian knot, a token of supremacy over Asia? At Issus, on the rectangular bay facing Cyprus, he had inflicted a crushing defeat on the great King of Persia, Darius Codomannus, who with the united forces of his kingdom had come to meet him. At Damascus he captured all the Persian war funds, and afterwards took the famous commercial towns of the Phoenicians, Tyre and Sidon. Palestine fell, and Jerusalem with the holy places. On the coast of Egypt he founded Alexandria, which now, after a lapse of 2240 years, is still a flourishing city. He marched through the Libyan desert to the oasis of Zeus Ammon, where the priests, after the old Pharaonic custom, consecrated him "Son of Ammon." He passed eastwards into Asia, crossed the Euphrates, defeated Darius again at the Tigris, and reduced proud Babylon and Shushan, where 150 years previously King Ahasuerus, who reigned "from India even unto Ethiopia over an hundred and seven and twenty provinces," made a feast for his lords and "shewed the riches of his glorious kingdom and the honour of his excellent majesty." Then he advanced to Persepolis and set on fire the palace of the Great King to show that the old empire had passed away. Pursuing Darius through Ispahan and Hamadan, he afterwards turned aside into Bactria, the present Russian Central Asia, and marched northwards to the Syr-darya and the land of the Scythians. Thence, with an army of more than a hundred thousand men, he proceeded southwards and conquered the Punjab and subdued all the people living west of the Indus.