370 EUSSIA IN EUEOPE. 



south, and representing tlie extremities of radii diverging from a common centre, 

 which would seem to have been in the raiddlo of the Ponto- Caspian isthmus. 

 This disposition can be explained only by a rapid lowering of the waters eastwards, 

 caused doubtless by the separation of the Caspian from the Euxine basin. When 

 the rupture of the Bosphorus caused the " divide " to emerge, the Caspian, at that 

 time twice its present size, was suddenly deprived of a portion of the waters that 

 had hitherto flowed to the common Ponto-Caspian basin. Hence the contributions 

 of the Volga and its other influents no longer sufficing to repair the losses caused 

 by evaporation, it was doubtless soon reduced to half its former size, and the sudden 

 subsidence produced by erosion those narrow lagoons still dotted over the Volga 

 delta and adjacent coast lands. 



The Caspian Sea. 



The modifications of outline caused by the alluvia of the Volga, of the Terek, and 

 of its other affluents are consequently insignificant compared with the vast changes in 

 remote times jDroduced in the form of the Caspian basin. The appearance of the 

 uncovered lands, the shells embedded in the soil, and the marine animals still 

 living in its waters leave no doubt as to the former extension of this inland sea. 

 There can no longer be any doubt that it formerly communicated either simulta- 

 neously or at different epochs both with the Euxine and Arctic Ocean. Hence, 

 although now completely land-locked, it may be regarded as geologically forming 

 portion of a vast strait flowing between the continents of Europe and Asia. 



The parting line betsveen the two seas is clearly indicated bv nature itself. 

 The river Kalaus, rising in the chalk beds at the northern foot of the Caucasus 

 about midway between the two seas, flows first northwards towards the depression 

 left by the old Ponto-Caspian strait, here ramifying into numerous branches, some 

 of which are lost in the sands, while others trend eastwards to the Kuma and 

 Caspian, But during the spring and autumn floods a portion of its surplus waters 

 finds its way westw^ards to Lake Manich, and thence from tarn to tarn to the Mediter- 

 ranean basin. Thus the two main branches of the Kalaus, known as the East 

 and Yt^est Manich, form a temporary channel between the two seas, intermittently 

 replacing the old strait. 



The question arises whether it might not be possible to restore the communi- 

 cation in such a way as to allow of large vessels passing uninterruptedly from 

 Gibraltar to Asterabad, or even by the old bed of the Oxus to the foot of the 

 Central Asiatic highlands. In any case it seems no longer possible to cut a 

 canal across the Ponto-Caspian isthmus free of locks, so that to connect the Sea of 

 Azov with the Caspian would be a far more gigantic undertaking than the 

 piercing of the Isthmus of Suez, Avith incomparably less commercial prospects. 

 The water-parting being some 80 or 86 feet above the level of the Sea of Azov, and 

 consequently about 170 feet above that of the Caspian, the cuttings for a canal no 

 more than 10 feet deep would be amongst the deepest ever executed, amounting to 

 at least 130 feet for a distance of over 30 miles. But a canal with locks adapted to 



