GLACIAL PHENOMENA IN THE ADIRONDACKS AND 
GRHAVIPEAIN VeAIICEY. 
INTRODUCTION. 
THIS paper was undertaken at the suggestion of Professor J. 
F. Kemp, of Columbia University, to whom the writer is indebted 
for much valuable assistance. The data on strie were gathered 
from all possible sources—from the published reports of the 
New York state museum, from the field notes of Professor 
Kemp,’ from the notes of Professor Cushing in the north and 
west, and from those of the writer inthe south. Especial thanks 
are due to Dr. Cushing for the information thus furnished. The 
study of the Pleistocene history of the Adirondacks has been 
fragmentary, and will be subject to much elaboration in the future. 
The purpose of the present paper is the correlation of such facts 
as are known from the writer’s observation and from the work of 
others, and the interpretation of these facts in their bearing on 
the erosion history of the region. Especial thanks are also due 
to Professor Kemp for assistance with the map. 
TOPOGRAPHIC RELATIONS OF THE ADIRONDACK REGION, 
The Adirondacks form the most conspicuous topographic 
feature of northern New York. Within this area of about ten 
thousand square miles are some dozen peaks which rise to alti- 
tudes of approximately five thousand feet. The valleys between 
these highest mountains are deep and narrow, their bottoms 
being about two thousand feet above the sea. This central mass 
of high peaks is composed entirely of anorthosite ; surrounding 
it are lower gneissic peaks of two to three thousand feet in alti- 
tude, with gentler outlines and broader intervening valleys. 
Towards the southwest this gneissic area stretches for some miles 
as a plateau, with undulations caused by old valleys, now largely 
drift-filled. Surrounding this crystalline area is a plain cut on 
‘Used by permission of the director of the United States Geological Survey. 
397 
