THE DEFLUENTS OF THE INLAND ICE-FIELD. 35 



great mountain-range, are of very little moment " to the movement 

 of land-ice, provided ice have snow enough." 1 



As the ice reaches the coast it naturally takes the lowest level. 

 Accordingly it there forks out into glaciers or ice-rivers, by which 

 means the overflow of this great ice-lake is sent off to the sea. The 

 length and breadth of these glaciers varies according to the breadth 

 or length of the interspace between the islands down which it flows. 2 

 If the land projects a considerable way into the great ice-lake, then 

 the glacier is a long one ; if the contrary is the case, then it is 

 hardly distinguished from the great interior ice-field, and, as in the 

 case of the great glacier of Humboldt in Smith Sound, the interior 

 ice may be said to discharge itself almost without a glacier. The 

 face of Humboldt's glacier is in breadth about 60 miles. This, 

 therefore, I take to be the interspace between the nearest elevated 

 skirting land on either side. It thus appears that, between the 

 inland ice and the glacier, the difference is one solely of degree, not 

 of kind, though, for the sake of clearness of description, a nominal 

 distinction has been drawn. The glacier, as I have said, will 

 usually flow to the lowest elevation. Accordingly it may take a 

 valley, and gradually advance until it reaches the sea. In the course 

 of ages this valley will be grooved down until it deepens to the sea- 

 level. The sea will then enter it, and the glacier-bed of former 

 times will become one of those fjords which indent the coast of 

 Greenland and other northern countries often for many miles ; or 

 these may be much more speedily produced by depression of the 

 land, such as I shall show is at present going on. By force of the 

 sea the glacier proper will then be limited to the land, and its old 

 bed become a deep inlet of the sea, hollowed out and grooved by the 

 icebergs which pass outwards, until in the course of time, by 

 the action of a force which I shall presently describe, the fjords 

 get filled up and choked again with icebergs, in all probability 

 again to become the bed of some future glacier stream. 3 Where 

 there is no fjord at hand, or where these defluents are not sufficient 

 to draw off the surplus supply of ice, the " inland ice " will " boil " 

 over the cliffs, overflowing its basin, and appear as hanging glaciers, 

 whence every now and again hugo masses of ice (the aerial equiva- 



1 'Quart. Journ. Geol. Soc.,' xxiv. 18G5, p. 1GG. 



- Properlj speaking, according to the ordinary nomenclature, the wholo of tho 

 ice, from the "neve*" downwards, .should be called "glacier;" but as we have 

 not yd penetrated sufficiently far into the interior to observe where the " neve"" 

 cuds ami the "glacier" begins, 1 have for tho sake of distinctness adopted the 

 above arbitrary nomenclature. 



'The origin of fjords i.-^ more fully developed in Section iv. of this Me ir 



(p. 58). 



i. 2 



