'Gazetteer of Arabia Vol. I' [‎192] (207/1050)

192 'ARAB
Thqsea tidea affect the level of the Shatt-al-'Arab throughout its entire length raising
.and lowering it by 6 to 9 feet in the neighbourhood of Basrah and by about 4 feet at Qurnah
village, and they are stronger than the current of the river. Sea water, however, does not
reach further than about 20 miles above Fao. The temperature of the Shatt-al-'Arab
stream is sometimes as much as 16° Fahrenheit higher than that of the Karan which en
ters it near Muhammareh.
Tributaries. —Tributaries of the Shatt-al-'Arab deserving of mention are two only,—
the Suwaib or Shwaiyib and the Karan, of these the latter is by far the more important.
The Suwaib, which enters the Shatt-al-'Arab from its left bank about 3| miles below
Qarnah village, comes from the direction of Hawlzeh and consists of the mingled waters,
so far as not expended in irrigation, of the Karkheh river from ' Arabistan and of the Jaha.
lah canal which taps the Tigris at 'Amarah.
The Karan, the only really navigable river in all Persia, joins the Shatt-al-'Arab, also
from the left bank, at a point about 22 miles by the course of the stream below Basrah.
The Karun is described in a separate article.
Island. —Above Basrah the river now contains no island worthy of note; between
Basrah and Muhammareh, on the contrary, the islands of'Ajairawlyah, Tawailah, Sham-
shamiyah and Umm-al-Khasasif, which are separately described under their own names,
form a continuous chain reaching nearly the whole way and below Muhammareh, also there
are several islands, namely Bahriyah, Gat'ah, Haji Salbuq or Muhilleh, Ziyadiyah and
Dawasir ; these form the subject of separate articles. Comparison of the most recent charts
with those of Colonel Chesney's expedition shows that the islands of the Shatt-al- 'Arab
are somewhat unstable, or, in other words, that the main channel of the river is not
constant.
In 1836 'Ajairawlyah included part of the present Tawailah; the rest of Tawailah
had not then been formed ; Shamshamiyah did not exist; Umm-al-Khasasif was smaller
than at present and belonged to the left instead of to the right bank ; Haji Salbuq on
the contrary belonged to the Arabian and not to the Persian side; and Ziyadiyah was
still a part of the mainland.
Navigation. —The Shatt-al-'Arab is in most respects a fine example of a navigable
river. It froms as it were a spacious vestibule to 'Iraq while the Tigris and
Euphrates resemble long but narrow corridors in the interior. An impressive though
common spectacle on the Shatt-al-'Arab is that of a tall ocean steamer ascending or
descending the river with swiftness and confidence.
The great blemish of the river as a waterway is the undredged and unlighted bar, 12
miles in breadth, which obstructs the entrance. The passage over the bar is marked
by a line of 5 buoys belonging to the British India Steam Navigation Company of which
the positions are occasionally changed; at the present time the buoys* extend from
about 6 to about 15 miles from Fao, the innermost or Bar Buoy alone being situated
within territorial waters at a distance approximately of 1'7 (nautical) miles from the
Persian and 2-8 (nautical) miles from the Arab shore. Steamers can cross the bar
daily with a draft of 18, and at spring tides (or once a fortnight) with draft of 21 feet;
but in both cases the combination of daylight and high tide must be awaited, a necessity
which is liable to cause a delay of as much as 14 hours. Moreover, the soundings Measurements of the depth of a body of water. on the
bar do not depend on the tide alone but are liable to be considerably reduced by a wind
from the north, and the position and depth of the channel are variable. The bar itself
■consists of soft mud, stiffer on the Persian than on the Arab side: a powerful steamer
may sometimes plough through even when the water is less than her draught, but she
will list to one side when inequalities of bottom are encountered and will not steer: in
this way a turbine steamer of the British India Company has been known to force
her way out on an actual draft of 16 feet when there were only 13 feet of water on the
bar. Any vessel which can pass the bar can also ascend to Basrah without difficulty,
the intermediate soundings Measurements of the depth of a body of water. being commonly 24 feet or more and tho worst places
not difficult.
In winter the night tides are the higher and vessels unable to cross on the day tide
can do so on the night tide, but pilots are reluctant to take a vessel of more than 18
foot draught over the bar at night.