Physical geography. By Mary Somerville ...

CHAP. XX. ASIATIC LAKES. 261
salt consumed in Russia. Its water yields 29 13 per cent. of saline
matter, and from this circumstance is more buoyant than any that
is known.1
The Lake of Aral, which is shallow, is 117 feet higher than the
Caspian, and has an area of 23,300 square miles; it has its name
from the number of small islands at its southern end, Aral signifying " island" in the Tartar language. Neither the Caspian nor the
Lake of Aral have any outlets, though they receive large rivers;
they are salt, and, in common with all the lakes in Persia, they are
decreasing in extent, and becoming more salt, the quantity of water
supplied by tributaries being less than that lost by evaporation.
Most of the rivers that are tributary to the Lake of Aral are diminished by canals, that carry off water for irrigation; for that reason
a very small portion of the waters of the Oxus reaches the lake.
Besides, the Russian rivers yield less water than formerly from the
progress of cultivation. The small mountain-lake, Sir-i-Kol, in the
high table-land of Pamer, from whence the Oxus flows, is 15,630
feet above the sea; consequently there is a difference of level between
it and the Dead Sea of nearly 17,000 feet.
The small number of lakes in the Himalaya is one of the peculiarities of these mountains. The Lake of Wuler, in the valley of
Cashmere, is the only one of any magnitude; it is but 10 miles in
The water of the Dead Sea contains 26-41 per cent. of saline ingredients, one of which is chloride of magnesium. The water of Lake Eltonsk
contains a small quantity of chloride of calcium.
[An analysis of the water of the Dead Sea, by James C. Booth and Alexander Muckle of Philadelphia, is given in Lieut. Lynch's official report of
the United States' Expedition to the Dead Sea and River Jordan. It is as
follows:
Specific gravity at 60~ F....................... 1-22742
Chloride of magnesium................................. 145-8971
calcium................................................ 31-0746'" sodium................................................ 78-5537
cc potassium............................................ 6 5860
Bromide of potassium................................ 1.3741
Sulphate of lime.................................................. 0-7012
264-1867
W ater..................................................... 7358133
1000
Total amount of solid matter found by experiment......267'000
The great specific gravity of this water does not indicate saturation,
because it is still capable of holding much chloride of sodium, and of course
still more chloride of magnesium in solution. Crystals of chloride of
sodium were found at a depth of 116 fathoms, which shows " that the water
of the Dead Sea is very unequally charged with its constituents, and that
no safe inference can be drawn from an analysis of surface water, and still
less of any specimen" from an unknown depth.O- O.cial Reporlt.]