psum~ occurs in large quantities in association with the rock-salt of
the Salt Range, but the local demand is small. There are also beds of
potash and magnesian salts in the same area, but their value and
quantity have not been thoroughly proved.

[Illustration: January-February.]

[Illustration: March to May.]

_Normal Rainfall._

I. N.W.F. Province. II. Kashmir.
III. Panjab E. and N. IV. Panjab S.W.

Fig. 16. Rainfall of different Seasons.

[Illustration: June to September.]

[Illustration: October to December.]

_Normal Rainfall._

I. N.W.F. Province II. Kashmir.
III. Panjab E. and N. IV. Panjab S.W.

Fig. 16 (_cont._). Rainfall of different Seasons.

CHAPTER V

CLIMATE

~Types of Climate.~--The climate of the Panjab plains is determined by
their distance from the sea and the existence of formidable mountain
barriers to the north and west. The factor of elevation makes the
climate of the Himalayan tracts very different from that of the plains.
Still more striking is the contrast between the Indian Himalayan climate
and the Central Asian Trans-Himalayan climate of Spiti, Lahul, and
Ladakh.

~Zones.~--A broad division into six zones may be recognised:

A 1. Trans-Himalayan.
B 2. Himalayan.
C. Plains 3. North Western.
4. Submontane.
5. Central and South Eastern.
6. South Western.

~Trans-Himalayan Climate.~--Spiti, Lahul, and Ladakh are outside the
meteorological influences which affect the rest of the Indian Empire.
The lofty ranges of the Himalaya interpose an almost insurmountable
barrier between them and the clouds of the monsoon. The rainfall is
extraordinarily small, and, considering the elevation of the inhabited
parts, 10,000 to 14,000 feet, the snowfall there is not heavy. The air
is intensely dry and clear, and the daily and seasonal range of
temperature is extreme. Leh, the capital of Ladakh (11,500 feet), has an
average rainfall (including snow) of about 3 inches. The mean
temperature is 43 deg. Fahr., varying from 19 deg. in January to 64 deg. in July.
But these figures give no idea of the rigours of the severe but healthy
climate. The daily range is from 25 to 30 degrees, or double what we are
accustomed to in England. Once 17 deg. below zero was recorded. In the rare
dry clear atmosphere the power of the solar rays is extraordinary.
"Rocks exposed to the sun may be too hot to l