GLACIER BAY 
17 
To the body of information gathered and published by 
these investigators 1 our addition was comparatively unim¬ 
portant. The five long days of our stay, though utilized 
to the utmost and replete with interest, served only for a 
partial review of the features of the immediate coast. As 
to the more general aspects of the topography and physical 
history we verified the work of our predecessors, but we 
were able to extend it only by bringing down to date the 
records of changing glacier fronts. 
Except near the mouth, the shores of Glacier Bay are 
treeless, and large tracts are almost destitute of vegetation. 
A variety of other facts show that this barrenness is due 
to the recent occupation of the surface by ice, and the ex¬ 
tent of the barren zone measures the amount of modern 
recession of the glaciers. Another series of phenomena, 
including vestiges of a forest and remnants of a moraine- 
delta, show that the epoch of expanded glaciers was pre¬ 
ceded by an epoch of contracted glaciers when the ice 
occupied less space than at present. Thus, from a condi¬ 
tion of minimum extent, the glaciers grew to a maximum 
of brief duration and then wasted away to their present 
dimensions. Vancouver’s narrative seems to show that at 
the time of his visit to the coast (1794) the ice was near 
its maximum, and subsequent observations, beginning with 
those of Muir in 1879, show rapid and nearly continuous 
retreat. The magnitude of this oscillation is perhaps 
without parallel in the records of glacial changes within 
the historic period. During the maximum epoch an ice 
flood not only filled Glacier Bay for thirty-five or forty 
miles, but submerged many islands and bordering hills 
1 John Muir, Cruise of the Corwin in the Arctic Ocean, p. 136, 1884; The 
Mountains of California, pp. 23-24, 1894. H. F. Reid, Nat. Geog. Mag., vol. 
iv, 1892 ; Sixteenth Ann. Rept. U. S. Geol. Survey, part 1, 1896. H. P. Cushing, 
Am. Geol., October, 1891. G. F. Wright, Am. Jour. Sci., Jan., 1887; The Ice 
Age in North America; Man and the Glacial Period. I. C. Russell, Am. Geol., 
March, 1892. 
