Schlagintweit, Hermann von; Schlagintweit, Adolf; Schlagintweit, Robert von: Results of a scientific mission to India and High Asia: undertaken between the years MDCCCLIV and MDCCCLVIII, by order of the court of directors of the hon. East India Company (Band 4): Meteorology of India: an analysis of the physical conditions of India, the Himálaya, western Tibet, and Turkistan (Leipzig, 1866)

GROUP L, EASTERN INDIA:
ASSAM AND THE KHASSIA HILLS.

1. ASSAM.

Barpetah.
Dibrugarh
Goalpara.
Gohatti.

Mangaldai,
Naugong.

Golaghat
Lakhimpiir.

Naziruaghat.

Sibsagar.

Tezpur.

Assam, by geographical position, is situated next to the northern limit of the tropical
region. Though in other parts of India the same and even higher latitudes still show,
with scarcely any modification, the full character of a tropical climate, we find in
Assam, in reference to the Indian seasons and the monsuns, a remarkably cool winter
without a corresponding excessive temperature in summer, and, what is more im-
portant still, a marked alteration in the ordinary direction of the wind, which, how-
ever, does not exclude a very great amount of rain.

The most prevalent winds in Assam are those blowing down the valley in a
north-easterly direction; this is another proof, as I shall have occasion to detail when
examining the winds, that Assam in winter as well as in summer is cooler than the
delta below it; whilst in the Panjab, exceedingly cool as it is in winter, the very heat
of its summer months causes an inversion in the direction of the winds.

For Assam the vicinity of the Himalaya and partly also of the Khassia and
Naga Hills may have a slight influence on cooling the temperature and so favouring
the direction of the wind towards the hotter region of the delta of Bengal; but for
the cold season at least the north-easterly winds have a much more general cause.
They are here the most northern limit of the periodical winds tending to restore the
equilibrium of temperature and pressure between the tropical seas and the continent