GEEENLAND SNOW AND ICE. 269 



the earlier g-laciation. Here at the time the later scratches were made the 

 ice could not bend downward so sharply as the small change in direction of 

 sloiDe. In other words, the ice traveled 3 feet horizontally, held up by its 

 cohesion, before it would bend downward 3 inches. On the other hand, 

 the earlier scratches changed instantly with the slope, and they themselves 

 were a deflection from the general glaciation of the region in which they 

 are found, and probably were not made at the time of greater thickness of 

 ice. All over Maine the earlier scratches bend sharply (in vertical planes) 

 around curves and some pretty sharp angles. Such facts prove that 

 deductions drawn from the behavior of thin glaciers do not in all respects 

 apply to thick ones. And 5^et if a thin glacier can not at once bend its 

 course downward under the force of gravity, it is evident that the same 

 causes, but operating under different circumstances, will limit the jDOwer of 

 even a great ice-sheet to flow down into cavities and glaciate them. The 

 ice, as shown elsewhere, must have been less than 200 feet thick at the 

 time of the formation of the Waldoboro moraine. The pressin-e on its bed 

 (neglecting the weight of moraine stufip) was less than 6 atmospheres. If 

 the thickness of the ice over Maine was only half a mile, the pressure at the 

 base was at least 84 atmospheres. Under this enormous pressure the 

 power of the ice to flow down into hollows was very great, but not unlim- 

 ited. Here and there a small portion of that ancient surface was protected 

 by a curve of the rock. 



GREENLAND SNOW AND ICE. 



The only region sufficiently explored to enable us to identify its con- 

 dition with that of northern New England in the time of the ice-sheet is 

 Greenland. Most of what we know of the condition of the interior is dxie 

 to the labors of the Danish geologists, of Torell, Nordenskjold, and Hoist 

 of Sweden, of Lieut R. E. Peary of the United States Navy, and others. 



The principal facts relative to the ice and snow of Greenland likely to 

 be of use to us in the interpretation of the facts as exhibited in Maine are 

 the following: 



The eastern coast is bordered by much shore ice. Near the southern 

 extremity the country is mountainous, and numerous glaciers occupy the 

 interior, but none reach the sea. Going north the inland ice descends lower 

 and the principal fiords serve as the outlet of glaciers, which- come down 



