CHAP. I I I . ] TH E KARUN AND FLOODING OF TH E EUPHRATES. 61
The modern town of Basrah is built on both sides of a
creek, or canal, and in its present decayed state, as compared
with former times, it still contains about 6000 houses, which
commence nearly at the edge of the main stream, and on its
right bank. Below the city this majestic river sweeps a
little more to the eastward; its width is about 700 yards ;
its ordinary depth 30 feet; and it forms three large islands
between this place and the small town of Mohammarah; ^ that
is; within a distance of 22^ miles by water, or 20^ miles direct,
S. 70° E. Here the Karun enters it, after a long course from
the Koh-i-zerd, through Shuster, Ahwaz, and other places.1
After this great accession to its waters, the Shatt el Arab
inclines a little more towards the south; during the remainder
of its course it passes many large villages, and almost continuous
belts of date-groves; and at length it reaches the sea,
which, at the bar, is 40 miles from Mohammarah. Between
this last place and the sea its average width is 1200 yards,
and its ordinary depth 30 feet.
The permanent flooding of the Euphrates is caused by the
melting of the snow in the mountains along the upper part
of its course. This takes place about the beginning of March,
and it increases gradually up to the time of barley harvest,
or about the last days in May, when it is usually at its
greatest height. At Port William the depth was found to
be increased by 13* feet; but, lower down, this varied, as may
be supposed, in different places, according to the width of the
stream. The river continues high, and its course very rapid,
for 30 or 40 days; but afterwards there is a daily decrease,
which becomes very small and regular towards the autumn.
From the middle of September to the middle of October
the river is at the lowest; and it even seems to be perfectly
stationary, until the rains commence, towards the end of
October, when there is a perceptible but variable increase,
which continues till the frost checks it in December, and
causes it again to fall. From this time until the beginning
of March it is subject to slight alternations, of decrease and
increase. The reader will find these variations placed before
1 See Chapter VIII. on Khuzistdn.