THE AEALO-CASPIAN BASIN. 127 



a brackish-water ami not a marine Fauna. We therefore perceive that 

 the separation of the region of tlie Pontns from that of the Aralo-Caspian 

 Sea could only have been effected by evaporation of the water, or diminu- 

 tion in tlie volume of the afliluents."* 



In regard to the positive diminution of the water-surface of Lake Aral 

 during the most recent historic times, the following quotation may be offered 

 from Humboldt's work, to which reference has alreaih' been made. He 

 says: "At the present time [aujourd'hui] Lake Aral, especially at its 

 northeastern end, is diminishing in size in an extraordinary manner. The 

 Bay of Sari-tchaghanak, for instance, extended, hardly eight years ago, to 

 the hill of Sariboulak, now twelve leagues distant from its present bank.'"t 



In regard to the some point Major Wood remarks as follows : '• The 

 sand dunes and tracts of hard clny occurring on the low shores of Lake Aral 

 point to the conclusion that extensive areas of country, which are now dry 

 land, were formerly covered by the water-spread of the lake. It has been 

 remarked that the mouth of the Syr-darya has become, in recent years, 

 fordable ; and that the depth of water between the island of Tokraak-Atta 

 and the north shore of Lake Aral has been diminished. It is also an estab- 

 lished fact that a minaret, which graybeards of the Kirghiz state was for- 

 merly situated on the edge of the eastern shore, is now at some hours' walk 

 distant from it ; and finally, since 1848, when it was a marshy swamp. Gulf 

 Abougir, at the southwest corner of the lake, has been entirely dried up, 

 and its bed is now under cultivation. There is no doubt that the cause of 

 this continuous shrinking in the area of Lake Aral is, that the evaporation 

 from its surface is in excess of the supply received by it from the Amu and 

 the S3r." t 



In describing the phenomena of the desiccation of the Aralo-Caspian Basin, 

 Humboldt gives no reason why evaporation should so steadily have been 

 getting the upper hands of precipitation. The object of this chapter being 

 simply to furnish evidence of the fact of a general desiccation, the di.><cu.*sion 

 of the causes of this extraordinary event is reserved for a succeeding chapter, 

 and the reader is now invited to pass on to the consideration of similar con- 

 ditions in an adjacent region. 



The importance, from the jioint of view of the present investigation, of the last paragraph induces the writer 

 to repeat it in the original : "Wir sehen demnach, dass die Trennung des Pontisehen vom Aralo-Kaspischen 

 Gebiete lediglieh diirch Verdunstung des Wassers oder Abnahmc der ZuflUsse veranlasst sein konnte." 



t 1. c., p. 271. 



t Journal of the Royal Geographical Society, Vol. XLV. p. 403. 



