20 RESOURCES OF CALIFORNIA. 
another for the Sierra Nevada and Klamath Basin ; another for 
the Great Basin of Utah; another for the coast south of Point 
Conception; and still another for the Colorado Desert. 
The causes of these peculiarities of climate are chiefly to be 
found in the position of the country—a narrow strip on the 
western side of the continent, bounded on the east by a high 
range of mountains that shuts the coast off from all the influ- 
ences of the interior; bordering on the wide Pacific Ocean, 
washed by a warm current flowing across from the China Sea; 
with a shore line that runs nearly north and south, and is ex- 
posed in all its length to the strong winds constantly blowing 
southeastward over the ocean. 
§ 21. Zemperature of the Middle Coast.—On the coast, 
between latitudes 35° and 40°, there is little difference in the 
temperatures of winter and summer. San Francisco is in the 
same latitude with Washington and St. Louis, but knows nei- 
ther the cold winters nor the hot summers which afflict those 
places. Ice is rarely formed in the Californian metropolis, and 
never more than an inch in thickness; and the thermometer 
never stays at the freezing point twenty-four consecutive hours. 
The lowest point which the thermometer has ever reached in 
San Francisco, since observations have been taken, was 22° 
Fahrenheit in January, 1862; and previous to that time it had 
never fallen below 25°; while in St. Louis it goes down to 12° 
every winter, and remains near that figure for many consecu- 
tive days. The lowest figures which the mercury reached in 
the daytime at San Francisco, in January of the years 1851, 
‘52,53, 754, and ’55, were respectively 30°, 35°, 41°, 25°, and 
33°, showing that in three Januaries out of five no ice at all 
was formed in the daytime; and when the thermometer fell to 
25° in 1854, the weather was declared to be colder than it had 
ever been before, ‘“ within the memory of the oldest inhabit- 
ant.” During nine years’ residence in the city, I never have 
seen ice formed here half an inch thick, and never saw the 
slightest film of it formed on water in a house. Snow some- 
times falls, but I have never seen the streets dressed in white, 
