284 G. F. Me E wen, 



nitude of the temperature reduction and its distribution vary with the 

 depth of the water, the slope of the bottom, the velocity of the winds, 

 the portion of the surface over which they extend and the steadiness 

 of the winds. 



To give an idea of the peculiarities of temperature distribution 

 that have been accounted for by means of these principles the foll- 

 owing results of observation are enumerated. 



The cooling effect of the upwelling water extends to a distance 

 of 600 kilometers from the coast off Cape Mendocino, lat. 40 and in- 

 creases to a distance of 2100 kilometers from the shore off San Diego r 

 lat. 32 45'. 



The temperature reduction in the summer is a minimum off San 

 Diego and a maximum off Cape Mendocino where the coldest surface 

 water is found. 



Temperatures as low as 14 in August have been found in certain 

 limited areas near the coast south of lat. 35, while the value 18 

 prevailed in the surrounding water a few miles away, both north and 

 south. 



Considering the complexity of the phenomena, the agreement be- 

 tween the theory and the observations has been very satisfactory, and 

 judging from the results already obtained it would be profitable to 

 carry on a more detailed and quantitative investigation following the 

 lines suggested in the present paper. 



The University of Illinois, U. S. A. 

 Feb. 8, 1912. 



Literature Cited. 



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