6 NEW YORK STATE MUSEUM 
details can seldom be brought in except for illustration of certain 
important points, and of necessity many questions will occur to 
readers interested in the natural features of their home regions 
which are not directly answered. It is hoped, however, that most 
of the important and striking geographic features in all parts of the 
State are explained, and that many local details will find ready 
explanation by the application of the principles set forth. 
Emphasis is here placed upon the genesis of geographic forms. 
It is one thing merely to state a geographic fact, such as the location 
of a mountain or lake or valley, but it is a far different thing to 
explain how the mountain or lake or valley came to be there. Every 
geographic form has a history, and if we fail to appreciate that 
history we lose the most interesting and valuable part of our geo- 
graphic training. Geographic facts, like all others, are more easily 
understood and remembered when the reasons for their existence are 
given, yet it must be admitted that the teaching of such rational 
geography is still in its infancy in the schools of this State. 
The use of a certain number of scientific terms is unavoidable 
in practice, but common terms only are employed and in every 
case these are carefully explained when first used in the text. 
Particular attention is directed to the photographs, maps and 
diagrams, all of which have been carefully selected or made for 
the express purpose of illustrating this text. Except for some 
quotations, references to original papers have been omitted, but at 
the end of the volume a list of the more important books and 
papers of general interest is given, and anyone desiring to broaden 
into wider fields or greater details can readily do so with the aid 
of those references. 
I have used many personal observations made during travels into 
almost every county of the State, but obviously the book could 
never have been written were it not for scores of devoted men of 
science who, during the last hundred years, have zealously labored 
to unravel the natural history of our great Commonwealth. I 
gratefully acknowledge my indebtedness to them all. 
I am under particular obligation to Dr J. M. Clarke, our able 
and efficient State Geologist and Director of Science, for his kind- 
ness in critically reading the manuscript and making important 
corrections and suggestions. 
W. J. Me 
Hamilton College, Clinton, N. Y. 
