MINERALS

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washed from the Himalayas, or from the old rock formations
 of Central India, and is scattered amongst recent
deposits or in river beds.
Geographically, the old geological formations of Central
and Southern India are cut off from the elevated regions
that lie to the north and west by the broad alluvial basin
of the Indo-Gangetic plain, which is fringed on the far
side by a series of recent deposits forming the foot-hills of
the higher ranges of older formation. Amongst these the
Siwaliks are the best known, and they are the most interesting
 because of the amount of palaeozoic remains which
they contain ; but they are not in themselves the seat or
origin of any great mineral wealth. The Siwaliks usually
occur as minor ranges flanking main watersheds, parted
by a broad valley from the lower spurs of the mountains
which they overlie geologically, and in this form they are
zasily accessible and readily recognised.
Looking southward from the Himalayan station of
Mussoorie across the chequered blue and yellow expanse
of the valley of Dehra (usually called Dehra Dun) the
Siwaliks appear as a serrated ridge, thickly clad with pines,
which may be traced distinctly as far as the eye can reach
eastwards and westwards against the faint blue of the
distant plains some thousand of feet below them. Very
different indeed is the same formation when viewed from
the summit of the Takht-i-Suliman Mountain on the trans-Indus
 frontier, nearly opposite the station of Dera Ismail
Khan.

Looking eastwards, here, towards the Indus, there is a
wonderful geological panorama spread outward. There is
no vegetation except such as scantily clothes the summit
of the magnificent pile of coral limestone rocks on which
one stands, just a scattered sprinkling of weird and wintry
junipers clustering round the peak of Kaisargarh which
towers over the surrounding cliffs at a height of 11,300
feet above sea-level. On the terraces at the foot of the
Kaisargarh peak, lying between it and the eastern ridge of
the mountain (but parted therefrom by the terrific precipices
of a gulley which splits its northern end and drops sheer to