is a ventilator, which, set in action by the motion of the train,
forces a rapid current of air through the wet network of fibres. Thereby
the air is cooled some eighteen or twenty degrees, and it is pleasant to
sit partly undressed in the draught.

Look a moment at the map. South of the Himalayas the Indian peninsula
forms an inverted triangle, the apex of which juts out into the Indian
Ocean like a tooth, but the northern part, at the base, is broad. Here
flow the three large rivers of India, the Indus, the Ganges, and the
Bramaputra. The last mentioned waters the plains of Assam at the eastern
angle of the triangle. On the banks of the Ganges stands a swarm of
famous large towns, some of which we shall visit when we return from
Tibet. The Ganges and Bramaputra have a delta in common, through which
their waters pass by innumerable arms out into the Bay of Bengal.

At the western angle of the triangle the Indus streams down to the
Arabian Sea. The sources of the Indus and Bramaputra lie close to each
other, up in Tibet, and the Himalayas are set like an immense jewel
between the glistening silver threads of the two rivers. On the west the
Indus cuts through a valley as much as 10,000 feet deep, and on the east
the Bramaputra makes its way down to the lowlands through a deep-cut
cleft not less wild and awesome.

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, defea