ON THE GEOLOGICAL AGENCY OF THE WINDS. 229 



tlirougli Florence in Italy, another from the month of the Amazon 

 through Aleppo m Holy Land (Plate VII.), would, after passing 

 the tropic of Cancer, mark upon the surface of the earth the route 

 of these winds ; this is that "lee country" (§ 200) which, if such 

 be the system of atmospherical chculation, ought to be scantily 

 supplied with rains. Now the hyetographic map of Europe, in 

 Johnston's beautiful Physical Atlas^ places the region of least 

 precipitation between these two lines (Plate VIL). 



639. It would seem that Nature, as if to reclaim this "lee" 

 land from the desert, had stationed by the way-side of these winds 

 a succession of inland seas, to serve them as relays for supplying 

 them with moisture. There is the Mediterranean, with its arms, 

 the Caspian Sea, and the Sea of Aral, all of which are situated 

 exactly in this direction, as though these sheets of water were de- 

 signed, in the grand system of aqueous arrangements, to supply 

 with fresh vapor, winds that had already left rain enough behind 

 them to make an Amazon and an Oronoco of. 



640. Now that there has been such an elevation of land out of 

 the water, we infer from the fact that the Andes were once cov- 

 ered by the sea, for their tops are now crowned with the remains 

 of marine animals. When they and their continent were sub- 

 merged — admitting that Europe in general outline was then as it 

 now is — it can not be supposed, if the circulation of vapor were 

 then such as it is supposed now to be, that the climates of that 

 part of the Old World which is under the lee of those mountains 

 were then as scantily supplied with moisture as they now are. 

 When the sea covered South America, the winds had nearly all 

 the waters which now make the Amazon to bring away with them, 

 and to distribute among the countries situated along the route 

 (Plate VII.) ascribed to them. 



641. If ever the Caspian Sea exposed a larger surface for evap- 

 oration than it now does — and no doubt it did ; if the precipita- 

 tion in that valley ever exceeded the evaporation from it, as it 

 does in all valleys drained into the open sea, then there must have 

 been a change of hygrometrical conditions there. And admitting 

 the vapor-springs for that valley to be situated in the direction 

 supposed, the rising up of a continent from the bottom of the sea. 



