THEIR SUBSTANCE. 
449 
geological analogies suggested themselves, which I do 
not venture to enlarge upon. It was evident that the 
accumulations had less variety of general configura- 
tion as they neared the coast, that their slopes became 
less sudden, their horizontalism more difiused, and that 
the water gorges were more ramiform. 
Reaching the sea, the solid ice-mass terminated ab- 
ruptly, presenting an escarped face with nearly verti- 
cal fracture, and varying in perpendicular height ac- 
cording to the profile of the protruding mass. The 
margin which defined this line of escarpment was clear 
and decided ; the only departure from its regular con- 
tinuity being at the gorges I have just referred to, or 
at cleanly-cut chasms, referable apparently to disrup- 
tion. 
I do not think the substance of the Greenland gla- 
cier differs materially from that of the Alpine. A frag- 
ment, examined by tbe microscope, exhibits the same 
vesicular structure ; and it breaks into numerous pieces, 
whose separation is determined by their capillary struc- 
ture. This fragmentary composition of the glacier ice 
enables you to walk on it without slipping. Its color 
is barely translucent, and at a distance as opaque as 
matte silver. It is only where cracks or chasms have 
been filled by waters and frozen up afterward, that we 
have a truly transparent ice. 
I have examined the neve, which forms so interest- 
ing a feature in the study of glaciers, only once in situ. 
This was at the small glacier north of 76°, where this 
substance occupied the upper portion of its trough. 
But for the partial cementation of its particles, and a 
grain-like character which could be detected on close 
examination, I should have regarded it as a mere ac- 
cumulation of snow-drift. 
F F 
