260 NINTH ANNUAL REPORT OP 



Remarks. — By clear days is meAt that no clouds were visible at 

 the times of observation ; by cloudy, that sonie were visible ; and by 

 rainy days, that some rain fell then, witliout reference to quantity. Not 

 being provided in time with a suitable pluviometer, the quantity of rain 

 cannot be put down in figures. The greatest amount that fell at any 

 one period was on the 22d February, after raining forty -eight hours 

 without intermission. The last rain of the past season occurred on the 

 20th May, 1853. There was a slight sprinkle afterwards on the 26th 

 .June, and on the 17th and 21st July. The first rains of the present 

 season occurred on the 15lh September and 10th October. The regu- 

 lar rainy season, however, did not set in until the 14th November. 

 About the middle of January the coast-range of mountains presented 

 the novel appearance of being covered with snow. The degree of cold 

 during this month was unprecedented. Not having a thcrmometro- 

 graph, the minimum, which generally occurs shortly before sunrise, 

 may not have been obtained. Sutter lake was frozen over on the 6th 

 and on the 21st of January, and remained so all the day of the 22(1. 

 This degree of cold is one of those extraordinary occurrences which is 

 sometimes experienced in the most equable and genial climates. Thus, 

 for instance, in 1507 the harbor of Marseilles was frozen over its whole 

 extent ; for which a cold of at least OA^ was requisite. Again, in 1709, 

 the Gulf of Venice, and harbors of Marseilles, Genoa, and Cette, were 

 frozen over. Such irregular occurrences are caused by the long preva- 

 lence of particular winds, and should not be taken into computation in 

 making an estimate of tlie mean annual temperature of au}^ place. 

 Notwithstanding, however, even the past extraordinary winter, we find 

 the mean annual temperature of Sacramento vicing with the land of the 

 olive and the vine. An isothermal line drawn across our continent, 

 from this point, would deviate as many degrees to the south as from the 

 western to the eastern side of the old continent. 



