inishing. This is, of course, due to the excess of evaporation over
the amount of water supplied by its two feeders, the Amu-darya and the
Syr-darya, both of which are seriously drawn upon for irrigation in all
the oases they flow through. Old shore lines and other indications point
to the level of the lake having once been 50 ft. above the existing
level. Nevertheless the general desiccation is subject to temporary
fluctuations, which appear to correspond to the periods recently
suggested by Eduard Bruckner (b. 1862); for, whereas the lake diminished
and shrank during 1850-1880, since the latter year it has been rising
again. Islands which were formerly connected with the shore are now some
distance away from it and entirely surrounded by water. Moreover, on a
graduated level, put down in 1874, there was a permanent rise of nearly
4 ft. by 1901. The temperature at the bottom was found (1900-1902) by
Emil Berg to be 33.8 deg. Fahr., while that of the surface varied from
44.5 deg. to 80.5 deg. between May and September; the mean surface
temperature for July was 75 deg. The salinity of the water is much less
than that of the ocean, containing only 1.05% of salt, and the lake
freezes every year for a great distance from its shores. The opinion
that Lake Aral periodically disappeared, which was for a long time
countenanced by Western geographers, loses more and more probability now
that it is evident that at a relatively recent period the Caspian Sea
extended much farther eastward than it does now, and that Lake Aral
communicated with it through the Sary-kamysh depression. The present
writer is even inclined to think that, besides this southern
communication with the Caspian, Lake Aral may have been, even in
historical times, connected with the Mortvyi Kultuk (Tsarevich) Gulf of
the Caspian, discharging part of its water into that sea through a
depression of the Ust-Urt plateau, which is marked by a chain of lakes
(Chumyshty, Asmantai). In this case it might have been easily confounded
with a gulf of the Caspian (as by Jenkinson). That the level of Lake
Aral was much higher in post-Pliocene times is proved by the discovery
of shells of its characteristic species of _Pecten_ and _Mytilus_ in the
Kara-kum Desert, 33 m. south of the lake and at an altitude of 70 ft.
above its present level, and perhaps even up to 200 ft. (by Syevertsov).

The fish of Lake Aral belong to fresh-water species, and in some of its
rapid tributaries