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NEW YORK STATE MUSEUM 



taken. But, unfortunately, owing to negative evaporation in the 

 storage period, the individual months of that period were too dis- 

 cordant for publication. The writer, therefore, does not give 

 any such diagrams in this connection. His present view is that, 

 for the reason stated, they can not be safely used. 



One or two general conclusions of some interest may be drawn 

 from figs. 11 to 13, inclusive. Taking the extreme low water as 

 represented by the year 1895, on Muskingum river, at 4.9 inches 

 for the whole year, with a rainfall of 29.8 inches, it is interesting 

 to observe that in the preceding year of 1891, there was a total 

 runoff of 8.7 inches, with a total rainfall of 30.5 inches. That is 

 to say, the rainfall for the year 1894 was 0.7 inch greater than 

 in 1895, but the runoff was 3.8 inches greater. This extreme 

 difference may be ascribed to the difference in the hight of ground 

 water. In 1895 ground water stood much lower than in 1893, 

 with the result of a lower runoff. 



On fig. 11, for the Genesee river, with a -.precipitation of 30 

 inches, the runoff is found to be 6 inches, while on fig. 8, with a 

 precipitation of 30 inches, runoff ordinarily may be expected to 

 be about 8 inches. This statement is made on the assumption 

 that the curve is drawn in a mean position, or in such a way as 

 to give average mean results, but it should not be overlooked that 

 Muskingum river observations are too few to draw absolute con- 

 clusions. The diagram, fig. 12, shows that there is some lack of 

 accuracy in at least one-half of them. 



Fig. 11 shows that on Hudson river, if during any year the total 

 rainfall should sink to 30 inches, the runoff may be expected to 

 be somewhat less than 10 inches, though the modifying effect of 

 full or low ground water may be taken into account in reaching 

 such conclusion. Probably there would be, due to elevation of 

 ground water, a variation of perhaps 2 inches. 



On the diagram of Croton river, fig. 13, it is also seen thai 30 

 inches precipitation may be expected to produce a little less than 

 7 inches of runoff, showing also that this stream has substantially 

 the characteristics of Genesee river. 



