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INDIA

As the monsoon currents sweep up from the southwest
 towards India, it is clearly the configuration of the
western coast that will in the first instance influence the
amount of local rainfall in the interior, for any cause
which tends to cool the condensed vapours will precipitate
he rain. If we look at a map of Western India we
shall see that from Karachi to the Narbada River, north of
which the Vindhya chain extends its terminal spurs towards
he sea, there is no obstruction to the north-eastward
sweep of the monsoon offered by elevated land or mountains.
 Along the valley of the Indus, and across the hot
sands of Rajputana and Sind, the rain-bearing currents
sass onward with no cooling medium to arrest their
progress and precipitate the moisture with which they are
charged, until they reach the Punjab and United Provinces,
and finally burst against the outer Himalayan ranges in
a watery deluge. The hills of Baluchistan stand almost
on the edge of the area influenced by the monsoon, which
loses much of its force in the northern part of the Arabian
Sea, and is hardly perceptible on the coasts of Western
Makran. Karachi and lower Sind, with the skirts of the
Baluch mountains, feel its influence, but the rainfall generally
 in Sind and Rajputana is small compared to that in
‘he sub-Himalayan regions. On the southern spurs of
the mountains between Kashmir and Nepal the average
monsoon rainfall is about 8o inches.
South of the Narbada the line of the Western Ghats,
which represents the western edge of the elevated plateau
of Central India, faces the ocean at a distance of some
40 or 5o miles from the coast. Here the monsoon currents
 are compelled to rise into the cooler atmospheric
strata in order to pass the barrier of hills, with the result
that they lose the greater part of their moisture before
‘hey reach the Central Provinces or Madras. Thus the
rainfall on the Ghats averages 120 inches, whilst a few
miles only beyond the highest ranges of the Ghats it may
fall to 20 or 30 inches.
But the most remarkable effect is produced at the
1ead of the Bay of Bengal. Here the gathering masses