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easterly direction from tire earth/ s rotation, are always blowing 
towards the equator ; whilst there is a regularity of climatic 
phenomena unknown beyond the tropics, where many and 
varied changes occur. 
The northern hemisphere, containing much more land than 
the southern, is subject, on account of deflected ocean currents 
and “ thermal ” changes, resulting from the varying radiations 
of the land and sea, to greater perturbation of the conditions 
that determine the formation and distribution of aerial mois- 
ture, and other meteorological phenomena ; and it is to one 
of the most remarkable of these, the monsoons of the Indian 
Ocean, that the climate and varying seasons of India owe 
much of their peculiar character. 
Monsoons. 
The great producers and distributors of rain in India, then, 
are the monsoons or periodic seasonal winds. The term is of 
Arabic origin, from “ Mausim/’ a season, and is applied 
to the great air- current that blows for one half of the year 
northwards, carrying the moisture taken up from a vast extent 
of the Indian Ocean, extending from Africa to Malacca ; whilst 
for the other half of the year it blows from the opposite direc- 
tion. The north-east monsoon corresponds to the north-east 
trade, and would be constant were it not for the counteracting 
influences which disturb the atmospheric equilibrium. Mon- 
soons are not peculiar to India, but occur in other regions 
where there are similar distributions of land and water. The 
Indian monsoons are caused in the following manuer : — About 
the commencement of April, when the whole surface of the 
continent of India becomes hotter than the sea, the rarified 
air rises, and is replaced by the comparatively cooler cur- 
rents drawn in from, and laden with moisture taken up by 
evaporation from, the Indian Ocean. This is the south-west 
monsoon, which, rising to higher regions, or, being intercepted 
by the mountain ranges, condenses its moisture in rain on the 
Western Ghats and on the coast of Aracan. Following a 
north-eastern course, it gradually loses its influence and its 
rain, as it approaches the northern limits of the continent. 
About October the winds are variable ; there is a reversal 
of the current, which begins to blow southwards for the most 
part as a dry wind, till on the Coromandel coast it brings 
moisture from the Bay of Bengal, which falls as rain on the 
coast of the Carnatic and on the Eastern Ghats ; whilst some 
parts of the South of India receive a certain amount of rain 
with each monsoon. 
