FEBRUARY 16, 1912] 
as Cook Inlet, attain their greatest eleva- 
tion in the St. Hlias-Fairweather Range 
where peaks rise 12,000 to 15,000 feet, 18,- 
000 feet in Mount St. Elias, and 19,540 
feet in Mount Logan. Here, naturally, the 
glaciers are largest, for from this central 
area the general elevation, as well as the 
heights of the peaks, diminishes toward 
both the southeast and the west. 
Back from the coast, and roughly paral- 
lel to the curving mountain barrier around 
the head of the Gulf of Alaska, is another 
lofty range sweeping northward from the 
Alaska peninsula, then eastward and 
southeastward. In its highest part, called 
the Alaska Range, are numerous lofty 
mountain peaks, including Mount Mce- 
Kinley (20,300 feet), the highest moun- 
tain in North America. Between this in- 
terior range and the coastal mountains is a 
broad depression occupied by Cook Inlet 
in the south and the Copper River Basin 
in the east; but in the extreme east the 
area between the two mountain ranges is 
mainly occupied by the great volcanic 
group known as the Wrangell mountains, 
whose peaks attain elevations of from 14,- 
000 to 16,000 feet. 
Naturally these lofty mountains of the 
interior are also the seat of numerous and 
large glaciers. But neither here, nor on 
the inner face of the coastal mountains, is 
there so full a development of ice and snow 
as along the coast. The snow line is 
higher, the glacier ends are all necessarily 
well above sea level, and the piedmont 
type of glacier is absent. The glaciers are 
essentially confined to the mountain val- 
leys, though some extend to the mouths of 
the valleys, and a few spread slightly be- 
yond them. It must not be inferred that 
the glaciers of the interior are insignifi- 
eant either in size or in number; merely 
that they suffer in comparison with their 
larger neighbors nearer the sea. Were 
SCIENCE 
243 
they the only glaciers of Alaska they would 
themselves attract wide attention because 
of their number and size. Besides being 
dwarfed by comparison with the coastal 
glaciers, these in the interior have the dis- 
advantage of remoteness and relative in- 
accessibility. They are, therefore, far less 
well known than the glaciers of the coast. 
The difference between the glaciers on 
the two sides of the coastal mountains may 
be typically illustrated by the Valdez- 
Klutena system, two glaciers which de- 
scend in opposite directions from a com- 
mon divide in the Chugach mountains, at 
an elevation of 4,800 feet. The Valdez 
Glacier, descending on the seaward side 
of the mountains, is 19 miles long and 
ends at an elevation of 210 feet, while the 
Klutena Glacier, descending toward the 
interior, is only 6 miles long and ends at 
an elevation of 2,000 feet. <A similar dif- 
ference is observed in the Nizina and 
Chisana glaciers, which descend from a 
common divide at an elevation of 8,000 
feet in the Wrangell Mountains, the 
former descending on the side facing the 
sea and therefore being much longer than 
the Chisana Glacier, which flows toward 
the interior. The total length of the two 
ice streams is about 47 miles. 
Beyond the Alaska Range, although 
there are numerous mountain and plateau 
areas of considerable elevation, lying far 
to the north, there is a general absence of 
existing glaciers, the only exception, so 
far as known, being on the Arctic slope of 
the Endicott Mountains (5,000-8,000 
feet). Here, in the summer of 1911, 
Phillip S. Smith and A. C. Maddren*? ob- 
served a number of small valley glaciers. 
Explanation of the Distribution of the 
Glaciers 
The distribution of glaciers in Alaska is 
not difficult to explain. That they are so 
41 Personal communications to the author. 
