384 



BRIGGS AND BELZ: INFLUENCE OF HAZE 



evaporation at a given station during a given month in 1912 to 

 its normal evaporation for the corresponding period has been de- 

 termined, and the mean of these ratios for all stations for each 

 month has been computed, together with the probable error. 

 These results are given in Table III. The results of the two meth- 

 ods of comparison will be seen to be in good agreement. The 

 mean value is given in Table IV, with the corresponding ratios 



TABLE III 



Ratio of the Monthly Evaporation in 1912 at Each Station to the Normal 



Evaporation 



STATIONS 



Amarillo, Tex 



Dalhart, Tex 



Garden City, Kans.. 



Hays, Kans 



Akron, Colo 



North Platte, Neb... 



Newell, S. Dak 



Edgeley, N. Dak.... 

 Dickinson, N. Dak.. 

 Williston, N. Dak... 

 Judith Basin, Mont.'. 



Nephi, Utah 



San Antonio, Tex.... 



Fallon, Nev 



Yuma, Ariz 



Mean 



Probable error 



0.93 

 1.04 

 0.89 

 0.89 

 0,86 

 0.80 

 1.01 

 0.95 

 0.89 

 0.82 

 0.64 

 0.74 

 0.69 

 0.92 

 0.87 



0.86 



=0.019 



1.09 

 1.05 

 1.24 

 1.14 

 1.03 

 1.12 

 0.99 

 0.94 

 0.92 

 0.78 

 0.77 

 0.87 

 1.16 

 0.89 

 0.82 



0.99 



=0.025 



JUNE 



1-15 



0.95 

 0.81 

 1.03 

 0.74 

 0.71 

 0.75 

 1.06 

 1.04 

 0.89 

 1.14 

 0.96 

 0.99 

 0.80 

 1.06 

 0.92 



0.9S 



=0.023 



JUNE 



16-30 



0.73 

 0.61 

 0.69 

 0.71 

 0,87 

 1.00 

 1.00 

 0.78 

 0.89 

 0.81 

 1.13 

 1.05 

 0.72 

 1.07 

 0.86 



0.86 



=0.028 



1.13 

 1.05 

 1,06 

 1,10 

 0.81 

 1.06 

 0.86 

 0.82 

 0.83 

 0,75 

 0,78 

 0.96 

 1.10 

 0.88 

 0.83 



0.93 



=0.024 



AUGUST 



1.05 

 0.91 

 0.99 

 1.04 

 0.82 

 0.96 

 0.88 

 0.72 

 0.94 

 0.80 

 0.89 

 0.96 

 112 

 0.88 

 0.81 



0.92 



=0.019 



SEPTEMBER 



0.81 

 0.82 

 0.92 

 1.01 

 0.68 

 0.82 

 0.67 

 0.64 

 0.75 

 0.77 

 0.90 

 1.00 

 1.13 

 0.99 

 0.93 



0.84 



=0.026 



for the temperature and sunshine. Sunshine records were not 

 available at all the evaporation stations, and the ratios given 

 were obtained from Weather Bureau records for 30 stations in 

 the region in which the evaporation tanks were located. 



It will appear from the ratios given in Table IV, that the evap- 

 oration during 1912 was abnormally low. The evaporation dur- 

 ing April was 14 per cent below nonnal. However, the average 

 number of hours of sunshine during April was also 7 per cent 



