3^^ Proceedings of Societies. [zoE 



in summer is found primarily in the declination of the sun north and south of the 

 equator. Exceptional southerly movements in winter are due to peculiarities in the 

 distribution of atmospheric pressure at the time which can only be revealed by the 

 cartographical study of immense atmospheric areas, embracing an entire continent. 

 All cyclonic movements in the Northern Hemisphere take place at a higher latitude 

 in summer than in winter. On the Pacific Coast, in summer, the cyclones move 

 eastward over British Columbia and to the northward, at which time California and 

 the Middle Plateau are invested with the "dry season." But this season is only 

 relatively dry, for rain does fall in every month of the year at various places within 

 this region. It is really the season of violent local disturbances, such as hail-storms, 

 thunder-storms, and cloud-bursts. The precipitation of the "dry season" results 

 entirely from local conditions, and is not the effect of cyclonic circulation and 

 movement, for we have shown that in summer the cyclones move eastward at a 

 very high latitude. The rainfall of summer then must come from the evaporation 

 of snow on the great mountain ranges of the Sierras. Observation proves this to 

 be a fact. The great masses of snow collected on these ranges during the passage 

 of the winter storms form the only source of moisture for the occasional showers 

 and local storms of summer. No snow in winter means no rain in summer, and 

 vice versa. Without these mountains to preserve the snows of winter for the water 

 supply of summer rain would entirely cease, the rivers dry up and the Middle Pla- 

 teau, with California, would become a veritable desert which the rains of winter 

 would hardly resuscitate. 



The cyclones of the North Pacific are first experienced at Alaskan stations in 

 their eastward passage from the Asiatic coast, then at stations on the coast of Brit- 

 ish Columbia, and finally on the coast of Washington and Oregon. These cyclonic 

 movements illustrate the importance and practical bearing of the meteorology of 

 Alaska on that of the northwest coast of the United States. The establishment of 

 telegraphic stations of observation in Alaska is the key to the solution of the prob- 

 lem of obtaining timely warnings of the approach of storms from the Pacific. Sta- 

 tions of observation on the ocean are impracticable, if not impossible, but their es- 

 tablishment along the coasts of Alaska and British Columbia is already demon- 

 strated. These stations must be connected by telegraph, for without the aid of 

 electricity in overcoming the loss of time over great distances, weather forecasts are 

 impracticable for any part of the country. When the Aleutian Archipelago and 

 Alaska are connected by telegraph with the United States then the approach of the 

 storms of the Japan current can be heralded several days in advance to the seaport 

 cities of the Pacific Coast, and the general weather forecasts for the interior made 

 with greater accuracy. The construction of a transcontinental railway connecting 

 the United States with Russia, through Alaska, would quickly provide the oppor- 

 tunity for the establishment of telegraphic stations of observation in Alaska. Sta- 

 tions on the Aleutian Islands could be connected by means of short land lines and 

 cables to the main land line from Alaska southward. With these outposts on the 

 very verge of the breeding ground of the cyclones of the North Pacific the most im- 

 portant mformation could be secured concerning their development, frequency, se- 

 venty and direction of progressive movement, and the data placed upon the daily 

 charts of the forecast official at San Francisco. Reports from these extreme west- 

 ern stations, t<,gether with those on the coast of British Columbia, would be of 



