MINERALS

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over the Malakand, and some of it finds its way westward
to Kandahar.
The Salt range of the Punjab, which extends across
the Indus at Kalabagh, is another inexhaustible source of
salt-supply. It is the “oldest known deposit of salt in the
world. As it underlies beds containing silurian fossils, it
belongs to a period not younger than Silurian 3" so that
it is older than the Kohat salt. The salt is here worked
from mines which are relics of Sikh industry in earlier
years, when the original workings were pushed forward
 with a reckless disregard for safety. The Punjab
Salt range mines have been so repeatedly described that
no further account of them is necessary here; but the
enormous advantage of the systematic mining introduced
under English supervision over the erratic methods adopted
by the Sikh workmen of past days is well illustrated by
what remains of the salt mines elsewhere.
In Kishm (an island on the Persian coast) the interior
of a mountain side has literally been scooped out, until
the unsupported upper layers forming the roof of the
mine crashed inwards and stopped further working. The
result is very curious. The interior of the mine is a large
dome-shaped cavity about as large as St. Paul's, in the
centre of which the débris from the roof is piled in a
ragged heap. The light of the sky breaks in where the
mountain side has fallen through at the apex of the roof,
and lights up the striated bands of salt, coloured in tints
of delicate salmon, yellow, and green, or deep maroon
(differing in this from the colouring of the Kohat salt,
which occurs in layers of black and deep rose colour),
with a weird and chequered lustre. The central pile of
débris is capped by a gigantic pillar of salt, and all around
are twisted columns, pendant from the roof or growing
from the floor, sometimes continuous, sometimes broken.
These are the stalactites and stalagmites formed by
deliquescent salt. Behind them, arranged, as it were,
round the base of the walls supporting the dome, are side
chapels hidden behind veils of the most delicate salt
tracerv that ever imitated Brussels lace ; and leading out-