PREFACE 



This report is a revision of Water Supply and Irrigation Papers 

 of the United States Geological Survey, Nos. 24 and 25 — Water 

 Resources of the State of New York, published in 1899. In regard 

 to calling the revised report the Hydrology of New York rather 

 than continuing the title previously given, it may be stated that 

 the information has been considerably extended and, while it is 

 true that it still pertains to the water resources of the State, it 

 seems to the writer that, on the whole, hydrology better expresses 

 the meaning than does the former title. 



Broadly, hydrology may be defined as that branch of physical 

 geography treating of water, and it is in this sense that the term 

 is used herein. Physical geography is an exceedingly elastic 

 term, and it is quite as proper to treat of the effect of restrictive 

 laws upon the development of the State as to treat of purely 

 political divisions in an ordinary textbook on geography. Any- 

 one writing upon geography, physiography, hypsography, geol- 

 ogy or hydrology knows that the lines separating these several 

 divisions are not very closely drawn and that one runs into the 

 other. Physiography treats in a general way of the present con- 

 dition of the waters of the earth, while geology treats in some 

 degree of their former condition, or at any rate of the effects 

 produced by water in a former condition. It is quite as appro- 

 priate, therefore, for the State Museum to publish a paper on the 

 hydrology of the State as to publish those relating more specially 

 to geology. 



What may be termed the geologic phase of the physiography 

 of New York has been treated by Professor Tarr, but his work 

 is incomplete in this — it does not treat of the flow of streams. 

 This report is intended to, in some slight degree, supplement 

 Professor Tarr's work. Moreover, hypsography is not extensively 

 treated, nor is hydrography. Tides and their effects, etc. are, 

 aside from a short reference to Hudson river, entirely omitted. 

 Only enough geology is given to illustrate the subject. 



