CLIMATE

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long-ago centuries, but enough can be gathered to show
that great changes have taken place. Islands have certainly
 disappeared, and harbours or ports have as certainly
been filled up. The Indus delta has advanced seawards
to such an extent as to leave the ancient ports of
medieval days 30 to 40 miles inland. Old channels
forming navigable “mouths” have disappeared even in
historic times, and new ones have opened out, the great
river itself having shifted 50 or 60 miles westward from
its original course, which once terminated in the Rann of
Kach. Within quite modern days the coast immediately
contiguous to Karachi has shallowed from the results of
dredging the Karachi channel, whilst monsoon influences
are apparent in the gradual increase of sand encroachment.
 Northward of Cape Monze, in the north-east bend
of the Arabian Sea (marked by Sonmiani Bay), the land
has here and there gained on the sea, the classical harbour
of Morontobara being now but an inland depression, and
the fishing village of Sonmiani, which once stood on the
edge of the bay, is already separated from the sea at low
water by a mile or more of mud flats.
The sea has swallowed up many an island which
must have once existed near the coast, and distributed
the debris along the foreshore. A small island off the
coast at Gwattar Bay was in the course of a single
year (1890) split into two, and 6 fathoms of water
were found in the channel that parted the divisions.
Probably that island has now disappeared altogether.
Many a bay on the Makran coast north of the Arabian
Sea has silted up into sandy scrub-covered flats during the
last twenty-five centuries ; the general impression formed
by a comparison with ancient records being that, on the
whole, the land has gained on the sea. Possibly the set
or drift of the south-west monsoon may have some
connection with the formation of the “bar,” which is a
prevailing feature of the entrance to nearly all the harbours
 and bays of the coast of Makran or of India. The
existence of this obstacle to free navigation renders some
otherwise good harbours, with deep soundings and