166 REPORT— 1873. 



numerous salt lakes and salt marshes, there can be no question that the northern 

 basin of the Caspian formerly extended over the whole plain of the Volga below 

 Saratov ; and no other cause can be assigned for its contraction, than the excess of 

 evaporation over the ret\irn of water hy rain and rivers. 



But such a reduction in the volume of water as must have taken place in order 

 to produce this lowering of level would have shown itself, it might be supposed, 

 in an increase of its salinity ; whereas the fact is that the proportion of salt (which 

 varies in different parts of the basin, and also at different seasons) is on the average 

 only about owe fourth of that which is found in oceanic water, and does not much 

 exceed one half of the proportion contained in the water of the Euxine. This 

 reduction, however, is fully explained by the observations of Von Baer, who traces 

 it to the number of shallow lagoons by which the basin is surrounded, every one 

 of which is a sort of natural " salt pan " for the evaporation of the water and the 

 deposit of its saline matter in the solid form. This process may be well studied in 

 the neighboui'hood of Novo-Petrosk on the eastern coast, where what was 

 formerly a bay is now divided into a large number of basins, presenting every 

 degree of saline concentration. One of these still occasionally receives water from 

 the sea, and has deposited on its banks only a very thin layer of salt. A second, 

 likewise full of water, has its bottom hidden by a thick crust of rose-coloured 

 crystals like a pavement of marble. A third exhibits a compact mass of salt, in 

 which are pools of water whose surface is more than a yard below the level of the 

 sea. And a fomlh has lost all its water by evaporation, and the stratum of salt 

 left behind is now covered by sand. A similar concentration is taking place in the 

 arm of the sea termed Karasu (Black Water), which nms southwards from the 

 nOrth-east angle of the Caspian ; for, notwithstanding the proximity of the mouths 

 of the great rivers, the proportion of salt there rises so gi-eatly above that of the 

 ocean, that animal life, elsewhere extremely abimdant, is almost or altogether 

 suppressed. 



This process goes on upon the greatest scale, however, in the Ivaraboghaz — 

 a shallow diverticulum from the eastern part of the middle basin, which is pro- 

 bably a " survival " of the former communication between the Caspian and the Sea 

 of Aral. This vast gulf communicates with the sea by a narrow mouth, which is 

 not more than about 150 yards wide and 5 feet deep ; and through this channel 

 a current is always running inwards with an average speed of three miles an hour. 

 This current is accelerated by westerly and retarded by easterly winds; but it 

 never flows with less rapidity than a mile and a half per hour. The navigators of 

 the Caspian, and the l\irLoman nomads who wander on its shores, struck with the 

 constant and unswerving course of this current, have supposed that its waters pass 

 down into a subterranean abyss (Karaboghaz, black gulf), through which they 

 reach either the Persian Gulf or the Black Sea. For this hypothesis, however, 

 there is not the least foundation. The basin, being exposed to every wind and to 

 most intense summer heat, is subject to the loss of an enormous quantity of water 

 by evaporation ; and as there is very little direct return by streams, the deficit can 

 only be supplied by a flow from the Caspian. The small depth of the bar seems to 

 prevent the return of a coimter-cm-rent of denser water, none such having been 

 detected, although the careful investigations made by Von Baer would have shown 

 its presence if it really existed. And thus there is a progressively increasing con- 

 centration of the water witliin the basin of the Karaboghaz ; so that seals v/hich 

 used to frequent it are no longer found there, and its borders are entirely destitute 

 of vegetation. Layers of salt are being deposited on the mud at the bottom ; and 

 the sounding-line, when scarcely out of the water, is covered with saline crystals. 

 Taking the lowest estimates of the degree of saltness of the Caspian water, the 

 width and depth of the channel, and the speed of the cm-rent, Von Baer has shown 

 that the Karaboghaz alone daily receives from the Caspian the enormous quantity 

 of three hundred and fifty thousand tons of salt. If such an elevation were to take 

 place of the surface of the bar as should separate the Karaboghaz from the basin 

 of the Caspian, it would quickly diminish in extent, its banks would be converted 

 into immense fields of salt, and the sheet of water which might remain would be 

 either converted into a shallow lake, like Lake Elton, which is 2C0 miles from 

 the present northern border of the Caspian — or a salt marsh, like those which 



