In the midst of summer, when the river is at its highest level and overflows the banks for miles, it is no pleasure excursion to steer ungainly boats between banks of sand and silt without pilots. On the second day a strong southerly storm arose, and the dangerous waves in the whirlpools of the current capsized many vessels and damaged others. Alexander made for the bank to look for fishermen who might act as pilots, and under their guidance he continued his voyage. The river became wider and wider, and the fresh salt breeze from the ocean became ever more perceptible; but the wind increased, for the south-west monsoon was at its height. The grey turbid water rose in higher billows and made rowing difficult, for the oars either did not touch the water or dipped too deeply into it. It was the flood tide running up from the sea which impeded their progress, but the ebb and flow of the sea was new to them. Eventually Alexander sought the shelter of a creek, and the vessels were dragged ashore. Then came the ebb, and the water fell as though it were sucked out into the sea. The boats were left high and dry, and many of them sank deep in the mud. Astonished and bewildered, Alexander and his men could get neither forward nor backward. They had just made preparations to get the ships afloat, when the tide returned and lifted them. Now they went farther down-stream and came in contact with the raging surf of the monsoon, which advances in light-green foam-crowned waves far into the mouth and changes the colour of the river water. The collision of the Indus current with the rising tide fills the fairway with whirlpools and eddies, which are exceedingly dangerous even for the best of vessels of the present day. Several ships were lost, some being thrown up on the banks, while others dashed together and went to pieces. After they had taken note of the regular rise and fall of the tide, they could avoid danger, and the fleet arrived safely at an island where shelter could be obtained by the shore and where fresh water was abundant. From here the foaming, roaring surf at the very mouth of the Indus could be seen, and above the rolling breakers appeared the level horizon of the ocean. With the best of the vessels Alexander went out to ascertain whether the surf could be passed through without danger and the open sea be reached. The trial proved successful, and another island was found, begirt on all sides by open sea. The ships then returned in the dusk to the larger island, where a solemn sacrifice was made to Ammon to celebrate the first sight of the sea and of the margin of the inhabited world towards the south.