207 
NOTES ON THE MUIR GLACIER REGION, ALASKA, 
AND ITS GEOLOGY. 
By H. P. C'rsHiNG, (levflaiul, O. 
CONTENTS. 
Page Page 
Introduction 207 Changes of level 3-21 
Description of the Region 208 The old forest 222 
Tributaries to Muir glacier 200 Its former extent 222 
Northern and Western branches 209 Its destruction 22:6 
Eastern branches 209 Its bearing on the historj- of the 
Dirt glacier 210 glacier 228 
White glacier 210 Disintegration of the rocks around 
Southeastern branch 210 Muir glacier 224 
Main valley and Main lake 210 Its Amd^unt 224 
Berg lake 212 Debris on (Jlacier-swept mountains. . 225 
Girdled glacier 212 Size of moraines 225 
Granite canon 218 Surface features produced by Muir gla- 
Recent recession of the glacier 214 cier 226 
Direct evidence 214 Surface produced on ridges at right 
Freshness and extent of the striii' ... 21t) angles to the movement 22li 
Condition of the eastern portion of Lakes 226 
the glacier ?17 Islands in Glacier bay 227 
Land slip on White glacier 217 Erosive power of Muir glacier 228 
Dying glacier 217 The gravels along Muir inlet 228 
(ilaciai deposits 219 Old surface features not obliterated. . 228 
Description 219 Sediment brought down by streams... 229 
Overrun by ice 220 Rock l)asins 229 
Origin , 220 
INTRODUCTION. 
Ill the Spring of 1890 a party was organized b}' Dr. H. F. 
Reid, of the Case Scliool of applied Science, Cleveland, 0., to 
proceed to Glacier bay, Alaska, for the purpose of mapping the 
basin of the Muir glacier, and of making as thorough an explora- 
tion as the time at their disposal would permit. The part}' con- 
sisted of Dr. Reid, Messrs. H. McBride, J. F. Morse, C. A. 
Adams, of Cleveland and R. L. Casement, of Painesville, O., and 
the writer. We reached Grlacier bay on the 1st of July, and 
were fortunate in finding Prof. John ^luir already in camp ther?, 
with Mr. Loomis, of Seattle, Wash. , as a companion. Our stay 
was made vastly more pleasant and profitable by Mr. ^Nluirs 
presence and knowledge of the region. He made the first ex- 
ploration of the amphitheatre occupied l)y the main mass of the 
glacier (see map), leaving camp in the middle of July, and in a 
solitary trip of ten days duration, passing completely around this 
amphitheatre. Our party had been preceded in work at this point 
by Prof. G. F. Wright, who spent a month here in 188(). Ilis 
retults are well known and his work was of value to us In many 
ways. 
Work in an unknown and diHicult region of consideral)le extent 
must necessarily be larsiclv thi' work of the scout. Detailed ob- 
