Chancourtois.Abich.Serda.Thorp.
Sodium chloride938.000810.67953.835938.837
Sodium
,,
carbonate
861.000543.84714.426773.110
Sodium
,,
sulphate
333.000258.68266.527369.095
Potassium sulphate55.00054.0697.65573.819
Magnesium carbonate55.00040.7157.308not determined
Magnesium
,,
sulphate
...22.67...
not
,,
determined
,,
Calcium carbonate......4.692...
Calcium
,,
sulphate
......5.928...
Calcium
,,
phosphate
......0.319...
Strontium sulphate......0.111...
Iron carbonate......0.488...
Manganese carbonate......0.360...
Ammonium chloride......1.699...
Silica18.0003.587.2847.53
Alumina0.3471.01
Nitrates.........0.05
Percentage of solids insolution22.6%17.34%21.10%22.48%

The specific gravity of the water was determined by Chancourtois as 1.0188, and by Abich as 1.0189, both at 19° C. As Abich points out, the water of Lake Van is nearly identical in composition with that of some of the soda-lakes at the south-eastern foot of Ararat, in the Araxes plain. In some of these the chloride, in others the carbonate, and in others again the sulphate of sodium is the predominating constituent. Probably the composition of the waters of Lake Van vary somewhat in different parts of the lake; Abich’s sample was certainly less saline than those of the other analysts.

The following analyses of the extraordinarily saline waters of Lake Urmi are appended for contrast rather than for comparison with those of Lake Van.

LAKE URMI.

Quantities of solids in solution estimated in parts per 100,000 parts of water.

Abich.[4] Günther and Manley.[5]
Chlorine12,686.88,536
Sulphates929.03631.2
Soda10,106.46,814
Potash...140.2
Magnesia1,099.3626.6
Lime37.770.6
Traces of bromidesTraces of barium.
...No traces either of bromine or iodine.

In this case Abich’s sample was a stronger solution than Günther’s, the percentage of solid salts being 22.28 and 14.89 respectively. Yet the relative proportion of the various salts is very similar, as shown by the following comparison of percentages:—

Abich.Günther and Manley.
Sodium chloride86.3786.203
Magnesium chloride6.946.816
Magnesium
,,
sulphate
6.084.150
Calcium chloride0.27...
Calcium
,,
sulphate
0.341.151
Potassium sulphate...1.741
100.00100.061