CLIMATE. 95 



There were four cold days in 1857-58 ; five in 1856-57 ; 

 seven each in 1855-56, and 1870-71 ; eight in 1867-68 ; nine 

 in 1858-59, and twenty-one in 1861-62. 



70. San Francisco Fogs. Dr. H. Gibbons, speaking of 

 the mists and fogs at San Francisco, says : 



" It is curious to observe the conflict between the absorbing 

 power of the air and the supplying power of the ocean, in re- 

 gard to moisture. Toward noon, when the wind rises, huge 

 columns of mist may be seen piled along the coast, three or 

 four miles west of the city, and pouring in, like a deluge, upon 

 the land. But the air of the land, which is always thirsty, 

 drinks it up with astonishing avidity ; so that the t *frnpending 

 wave, though in a current moving from thirty to fifty miles 

 an hour, makes slow progress. By the middle* of the after- 

 noon, it is within a mile or two of the city ; and there it 

 stands, like a solid mass of water, several hundred feet in 

 depth, rolling and tumbling toward you, (not without grand- 

 eur and majesty) and threatening to overwhelm you in a few 

 seconds. You await its coming, but it comes not ; it even re- 

 cedes, to return and recede again. Not until the sun has lost 

 his calorific power, does the atmosphere reach the point of 

 saturation ; and then, toward sunset, or later, everything is 

 submerged by the vapory flood. In the course of the even- 

 ing, the wind falls. During the night, the mist is gradually 

 dissolved, and disappears from the lower stratum of air, while 

 it forms a heavy cloud above. About the middle of the fore- 

 noon, the cloud is dispersed by the rays of the sun. The dis- 

 persion is rapid, the sky often becoming entirely clear in less 

 than half an hour. 



"If it be possible to distinguish between fog and mist re- 

 garding the former as impalpable, and the latter as composed 

 of palpable particles of moisture I may remark that mist be- 

 longs only to the summer, and fog to the winter climate of San 

 Francisco. There is no mist in winter, and no fog in summer. 

 At all seasons, the drying tendency of the atmosphere is ob- 

 servable. You notice none of those phenomena which, in 



