HYDROLOGY OF NEW YORK 



140 



records at the north ends of the valleys in this vicinity, as at 

 Hemlock lake, Avon, Penn Yan, Lyons and a number of other 

 places, and the Geneva record is probably not very far out of the 

 way. 



In order to compare the precipitation record with that of the 

 drain gages the precipitation for the water years 1883 to 1889, in- 

 clusive, is given — the yearly mean for the period is 25.99 inches. 

 The yearly mean precipitation at Hemlock lake for the water 

 years 1877-1900, inclusive, is 27.70 inches. The mean of the stor- 

 age period at Geneva from 1883-1889, inclusive, is 8.89 inches, 

 while at Hemlock lake it is 12.21 inches, indicating that if these 

 two records are otherwise comparable the Geneva record is short 

 in the storage period a little over 3 inches. 



Continuous records were kept at Penn Yan from 1829-1867. 

 The mean rainfall for the water year of this period of forty-eight 

 years was 27.93 inches, or substantially the same as Hemlock lake. 



For the calendar year of 1899 the recorded precipitation at the 

 Geneva Agricultural Experiment Station was 19.35 inches, while 

 at Lyons for the water year 1899 it was 20.91 inches. On account 

 of the uncertainty as to the winter months, the Geneva record is 

 not used in compiling the average precipitation of the Oswego 

 basin as given in table No. 34. 



In table No. 33, Percolation of Drain Gages at Geneva Agri- 

 cultural Experiment Station for the Water Years 1883-1889, In- 

 clusive, we have the runoff of the three drain gages given for the 

 water years, divided into storage, growing and replenishing 

 periods, and in table No. 34, Runoff Data of Oswego River at High 

 Dam for the Water Years, 1897-1901, Inclusive, we have given the 

 rainfall, runoff and evaporation for these years. This table shows 

 that the average runoff for the years included was 11.07 inches, 

 while the preceding table shows that the average runoff from the 

 sod for the seven years, 1883-1889, inclusive, was 5.07 inches; 

 from bare soil, 7.55 inches, and from cultivated soil, 11.12 inches. 

 The average rainfall during the years 1883-1889, inclusive, was 

 according to the record at Geneva 25.99 inches, while during the 

 years 1897-1901, inclusive, it was 36.50 inches. This excess of 

 rainfall in the period 1897-1901, over what it was in the period 

 1883-1889, would, by itself, cause a largely increased runoff. In 



