Glacier Work.— Scott. 215 
A BRIEF SUMMARY OF GLACIER WORK. 
A. C. Scott, Kingston, R. I. 
TABLE OF CONTENTS. 
History 215 
Classification 218 
Alpine and Polar 218 
Comparative Size 219 
Velocity of Flow 221 
Glacier Motion. General Theories 222 
Movement in Zones of Fracture and Plasticity 226 
Advance and Retreat of Glaciers 235 
Line of Lower Limit 236 
Glacial Drainage 237 
Stratification 238 
Erosion 239 
Moraines. 
243 
Continental Glaciers 24-5 
Origin of Ice Age -•^*' 
AVork of Ice Sheet 248 
249 
251 
Erosion 
G roo ves 
Striag 252 
Transportation 253 
Glacial Lakes 255 
Glacial Drift and its Divisions 25 , 
258 
Terminal Moraines 
Bskers and Karnes 
259 
260 
Conclusion 261 
INTRODUCTORY NOTE- 
The summary of glacier work presented in the following pages 
which was written as a seminary paper in a course in geology at the 
University of Wisconsin, does not presume in the least to be a com- 
plete resume of the subject. 
In attempting to arrange an outline of the work it was appar- 
ent that the literature nowhere included a summary, and so it appeared 
On completion of the paper that the few facts therein collected might 
be more or less useful to others interested in glaciology. Indeed this 
idea may seem sufficient apology for publishing an article that does 
not treat the subject exhaustively. 
Present day knowledge concerning- the subject of gla- 
ciation has developed almost wholly wathin the past century. 
One of the earliest important statements concerning glac- 
iers was made by James Hutton. the father of modern geol- 
ogy, in his "Theory of the Earth, with Proofs and Illus- 
trations," which was given to the world in I7q5. This work 
was evidently intended by its author to consist of four parts, 
though prior to his death in 1797 only two parts had been 
