1 8 THOMAS L. WATSON 



BIG ISLAND. 



Locatio?i, description and topography . — The location of the island 

 is immediately off the southern coast of Baffin Land, in Hudson 

 Strait, and separated from the mainland by a narrow channel of 



water, ten to twenty miles wide, known as White Strait in 



north latitude 62° 30' to 63° and west longitude 70° to 71° 10'. 

 It is some twenty-five to thirty miles in the direction of its 

 longest axis, which is northwest and southeast, and has an aver- 

 age width of from five to ten miles. The coast is a steep and 

 irregular one, being much cut up by fiords and embayments. 

 The highest land reached on the island was 470^ feet above sea 

 level. Its surface has been deeply incised by interlocking 

 fiordic^ valleys, which are quite broad at their tops, with the 

 ridges or divides between, of a typical moutonneed form. These, 

 of course, are on their tops narrow in proportion as the valleys 

 are wide. The rise and fall of the tides is about thirty feet. 

 The topography shows marked signs of glaciation, though, in 

 places, it has been greatly modified by weathering, which has 

 been chiefly of the mechanical kind and on a large and rapid 

 scale. Notwithstanding the great amount of mechanical weather- 

 ing, due almost entirely to frost action, chemical disintegration 

 is distinctly noticeable. Many sections which have been but 

 recently uncovered by ice are rough and angular, with nearly 

 every trace of glaciated form obliterated. 



Kind of rock.— Th^ rocks consist of regularly banded horn- 

 blende-biotite gneiss, complexly folded and gray in color, the 

 intensity of which varies according to the amounts of the dark 

 minerals present. The gneisses are intersected by numerous 

 pegmatite veins composed of the same minerals. 



Proofs of elevation in raised beaches. — In nearly every valley 

 studied, one of its most prominent and striking characteristics 

 was the occurrence of shore lines in the form of distinct beaches. 

 Sometimes a full and complete series of half Mozen or more of 

 these would be found in a single valley at different elevations, 

 'All altitudes were measured with an aneroid barometer. 

 = The term ''fiordic'" is here used in the sense of "fiord-like." 



