402 



A JOURNEY IN BRAZIL. 



merged. To this I can only answer that, in the State 

 of Maine, I have followed, compass in hand, the same 

 set of furrows, running from north to south in one un- 

 varying line, over a surface of one hundred and thirty 

 miles, from the Katahdin Iron Range to the sea-shore.* 

 These furrows follow all the inequalities of the country, 

 • ascending ranges of hills varying from twelve to fifteen 

 hundred feet in height, and descending into the inter- 

 vening valleys only two or three hundred feet above the 

 sea, or sometimes even on a level with it. I take it to 

 be impossible that a floating mass of ice should travel 

 onward in one rectilinear direction, turning neither to 

 the right nor to the left, for such a distance. Equally 

 impossible would it be for a detached mass of ice, swim- 

 ming on the surface of the water, or even with its base 

 sunk considerably below it, to furrow in a straight line the 

 summits and sides of the hills, and the bottoms of the inter- 

 vening valleys. It would be carried over the inequalities of 

 the country without touching the lowest depressions. In- 

 stead of ascending the mountains, it would remain stranded 

 against any elevation which rose greatly above its own base, 

 and, if caught between two parallel ridges, would float up 

 and down between them. Moreover, the action of solid, un- 

 broken ice, moving over the ground in immediate contact 

 with it, is so different from that of floating ice-rafts or ice- 

 bergs that, though the latter have unquestionably dropped 

 erratic boulders, and made furrows and striae on the surface 

 where they happened to be grounded, these phenomena will 

 easily be distinguished froni the more connected tracks of 

 glaciers, or extensive sheets of ice, resting directly upon the 

 face of the country and advancing over it. 



* See " Glacial Phenomena in Maine," Atlantic Monthly, 1866. 



