28 THE POLAR GLACIERS. 



making the beds of the garden of the world. These are no idle 

 or impossible fancies. Not only are they the results of rigorous 

 calculation, but they accord perfectly with the unmistakable 

 evidences which the ocean has left, all over our land, of its recent 

 w T ork and presence. 



The time-honored geologist, Sir Charles Lyell, lays great stress 

 on the quantity of land and the configuration of continents, as 

 chiefly efficacious in the great climatic changes. But it may be 

 pertinently asked, what becomes of his continents and configura- 

 tions when the seas of one pole advance to the other, as they 

 unquestionably do, as they cannot but do, every 10,500 years, 

 obedient to the transfer of vast ice- weights from one end of the 

 world to the other ? On all the mountains of New England 

 there are sea-lines at elevations of 2,000 and 3,000 feet, and Lyell 

 himself has recorded the facts. When the ocean was that deep 

 over Boston, there were no continents in the northern hemisphere. 

 Undoubtedly the height and direction of mountain -ranges, the 

 trending of sea-shores, and the course of the ocean currents, 

 have much to do with local climates. But instead of the relative 

 quantity or location of land and sea having any agency in pro- 

 ducing the glacial periods, it is these periods which produce the 

 land and the sea. 



So much for the causes and conditions which pertain to the 

 geography of the present and the future. When now we turn 

 back a few of the leaves which tell us of the past condition of 

 our planet, we immediately see that the same causes have been 

 at work in recent geological times on a much more extensive 

 scale in fact, that they have been the chief agents in composing 

 and modifying the present surface of the earth outside of the 

 tropics. Over all the northern portions of Europe, Asia and 

 North America, are found the unmistakable evidences of exten- 

 sive and recent ice-work. Bowlders of every size, some worn 

 and some angular, are scattered in immense quantities over all 

 the country, on the hills, on the plains, in places where the only 

 possible explanation is that they were lifted up, carried, and 

 dropped, just where they are found ; and the great iceberg was 

 the carrier. The face of the rock-beds, wherever brought to 



