before the Geographical Society, May 27,1867. 23 
titudes in the surrounding region, and that the levels of the 
Sea of Aral and the sist are also different, and are sepa- 
rated by the great plateau of Ust-Urt. As it is impossible to 
explain the existence of the much deeper cavity of the Dead 
Sea except by a greater sinking of the earth’s crust, so is such 
a shai onion precisely what geologists would ex to see 
realized as a natural and compensating result of the corres- 
nding upheaval of the adjacent lofty mountains of Asia. 
This being the conclusion at which geologists have arrived, 
let us see if it be interfered with by any reliable histori ical 
records, As to the knowledge possessed by Alexander, or his 
contemporaries, it really does not touch the sgag of the 
relative courses of the Oxus and Jaxartes toward their mouths, 
For Alexander crossed the Oxus at about 400 miles ahve: its 
mouth, and the most western point at which the great con- 
queror "reached the Jaxartes was Cyropolis, where he passed it 
to defeat the Scythians ; and that spot is about — 
from the Aral Sea. eeeceungeg neither Alexander nor his 
nerals could know anything of the real course of elthée 3 river 
for great distances above their mouths. Scholars and compar- 
ative geographers doubt, indeed, if any weight can be attached 
to the unanimous statement of the Greeks, ‘hat both the Oxus 
and Jaxartes flowed into the Caspian, by mouths some 300 
miles apart,* when they see how equally unanimous were the 
ing the Caspian to be but a gulf of the Northern Ocean! 
we see how persistently the followers of Alexander 
confounded the Jaxartes itself with the Tanais, and fancied 
that they had doubled back upon the rear of Europe. 
“The expedition of Alexander,” says Humboldt, “far from 
extending or rectifying the geography of the Caspian Sea, 
te Papa the Tanais with J ek and ne oe with 
e Paropamisus or Hindu Kush. t is through a 
si i sn re great Macedo- 
graphical hor of a Caspian Sea. > Further on, he says, “ Some 
traces of the Sea of Aral, described as a oreat basin to the 
east of the Ural or Jaike River, are indeed found in Menan- 
der, the Byzantine historiographer; but it is only with the 
series of Arabian geographers, at the head of whom, in the 
tenth century, we must place El-Istachry, that we first obtain 
a certain knowledge of the topography of the countries.”§ 
elus, ‘both quoted by Stra Sira 
¢ ‘Asie Centrale,’ org 14, ¢ Ibid., p. 153. § Ibid, p 156. 
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