ALASKA GLACIERS 
11 4 
HANGING VALLEYS 
Of the various classes of evidence from which the his¬ 
tory of Pleistocene glaciation is inferred, the physiographic 
is most available to observers who see the land chiefly from 
the deck of a vessel. Ice-scoured surfaces referable to 
the ancient glaciers were occasionally discovered during 
our journey, and a few drift deposits were closely exam¬ 
ined; but such observations served chiefly as checks on 
inferences from topographic form. 
The general characters of the physiographic data which 
may be used in such studies are familiar and need not be 
recited here, but a special sculpture feature — the hanging 
valley—may need introduction to some of my readers. 
Its utility in the interpretation, discrimination and estima¬ 
tion of the work of Pleistocene glaciers has been little 
appreciated until quite recently, 1 but in the study of the 
Alaska field it was found extremely useful. 
A hanging valley is a small U-valley tributary to a 
larger valley, the floor of the smaller being considerably 
higher at the junction than the floor of the larger. Many 
of them are short, high-grade troughs, heading in cirques; 
some are mere cirques, without troughs — spoon-bowl hol¬ 
lows, high on the walls of main valleys. They are asso¬ 
ciated with other evidences of glacial sculpture, and the 
elevation of their floors is believed to result, as a rule, 
1 Lake Chelan, by Henry Gannett: Nat. Geog. Mag., vol. ix, pp. 417-428, 1897. 
Glacial erosion in the valley of the Ticino, by W. M. Davis : Appalachia, vol. 
ix, pp. 136-156, 1900. Glacial erosion in France, Switzerland and Norway, by 
W. M. Davis: Proc. Boston Soc. Nat. Hist., vol. xxix, pp. 273-322, 1900. 
Review of the last by T. C. Chamberlin: Jour. Geol., vol. vm, pp. 568-573, 
1900. 
Davis’s second paper reviews the literature, points out that McGee, De Lap- 
parent and Richter had advanced somewhat similar ideas as to the origin of 
hanging valleys before the appearance of Gannett’s paper, and mentions an 
unpublished address by Penck. The glacial explanation of the hanging valleys 
of the Alps is opposed by Bonney and Garwood in Quart. Jour. Geol. Soc. 
London, vol. lviii, pp. 690-718, 1902. 
