REPORT ON FORESTS. 147 



Pequannock. Run-off furnished by Clemens Herschel, C. E., Supt. Bast 

 Jersey Water Company. Rain-fall prepared from N. J. State Weather 

 Service records for Charlottesburg, etc., as the Oak Ridge record 

 furnished by Herschel does not appear to be representative of the 

 rain-fall on the water-shed. 



Other New Jersey Streams. From Report on Water-Suppty, Geological 

 Survey of New Jersey, 1894. Temperature revised to date from rec- 

 ords of New Jersey State Weather Service. 



Tohickon, Neshaminy, Perkiomen. Annual Reports of Philadelphia Water 

 Department, also paper in Vol. XIV, Proceedings of Engineers' Club 

 of Philadelphia, by John E. Codman. 



Potomac. The Hydrography of the Potomac Basin, by Cyrus C. Babb, 

 Proc. Am Soc. C. E., Vol. XXVI. Two years of this record show 

 such large discrepancies in run-off as compared with the rain-fall that 

 they are rejected in making up the average. 



Savannah Results of Stream Measurements, U. S. Geological Survey, 

 1891, page 148. Instead of taking the rain-fall of Augusta alone I add 

 19%, which is the average excess over Augusta rain- fall shown by 

 five stations which fairly represent the entire water-shed. 



Muskingum, Dtsplaines. "Stream-flow in Relation to Forests " Geo. W. 

 Rafter. Proceedings American Forestry Association, Vol. XII. 



Kansas. Bulletin 140. U. S. Geological Survey, and rain-fall from U. S. 

 Weather Service Bulletins. 



Clear Creek.\o\. XVII, Tenth Census, p. 52 (336). 



Sweetwater. Bulletin 140, U. S. Geological Survey, p. 322. 



Lea Transactions American Society of Civil Engineers, Vol. XVIII, 

 p. 297. 



Wandle, Thames, Wendover Springs. Proceedings Institute of Civil En- 

 gineers, Vol. CV, p. 56, etc. 



A careful examination of the foregoing table must convince 

 any candid observer that there are more potent agencies than 

 forests effecting the evaporation ; thus the evaporation on several 

 streams, which have more than half the area of catchment 

 covered with forests, is as follows : Connecticut, 20.87 ; Upper 

 Hudson, 21.19; Hackensack, 24.61; Passaic, 23.38; Great Egg 

 Harbor, 28.93 ; Potomac, 24.82 ; Savannah, 31.85. 



Here we have a range of n inches in evaporation without a 

 corresponding range in forest conditions, and it will be found 

 that generally the larger evaporation corresponds with the 

 higher temperature. While, in the State of New York, the 

 short three-year series on the Genessee river appears to show 

 about 6 inches more evaporation than the figures for the Upper 

 Hudson ; on the other hand, the deforested catchment of Skan- 



