\ 
312 H. Gibbons on the Climate of San Francisco for 1855. 
above 84°. To what extent we are wont to suffer from heat in 
this latitude of 374 degrees, may be determined from the fact 
that in the year 1855, the mercury rose to 80° or above, oniy on 
six days. In 1851 it reached that point on nine days, in 1852 
on fourteen days, in 1853 on eleven days, and in 1854 on twelve 
days. More than one half of these warm days were in the au- 
trmn, and less than one third in the summer months. 
he greatest degree of cold in 1855, was 29°, and the mercury 
was at or below the freezing point on six days, all of which were 
in December. It was below 40 on ten days, three of which 
were in January, and seven in December. In some winters there 
is no freezing weather, and the most tender plants may bloom in 
the gardens from season to season. The lowest temperature on 
my record is 25°,—in January 1854. Next to this 28°, in De- 
cember 1850, and next, 29° in December 1855. In the year 
1853 the mercury did not fall below 40°. The whole number 
of freezing mornings in 1850 was two, in 1851 one, in 1852 
none, in 1853 none, in 1854 three, in 1855 six. The coldest 
noonday in 1855 was 41°. In December 1850 there was one 
day when the noon temperature was 38°, and in January 1854, 
a day when it rose no higher than 37°. Such weather however 
is extraordinary, and when it occurs every body declares the like 
was never before known, and that the climate is changing 10 
deference to the American population. 
The warmest morning in the year was 64°. The warmest 
morning for the last five years was 66°. There are but one or 
two mornings in the year which approach this figure. A sultry 
night is unheard of. A single night that could be called warm 
has happened in five years, and then the thermometer was 76° 
at 10 p. m. and 66° next morning. 
The range of the thermometer in 1855 was 61°. In 1851 the 
range was 54°; in 1852, 63°; in 1853 48°; in 1854, 62°. 
The greatest barometric pressure in the year was 30°16 in., the 
lowest 29-40 in. Range 0-76 in..—which is nearly the mean 
range fora series of years. The lowest point reached in five 
years was 29-20 in.,—during a violent southerly storm. 
The time occupied by the various winds is thus represented : 
Land winds, NW 33 days. Sea winds, SE 16 days. 
ts &“ N 95 « &“ ts Ss 4s “ 
6 “ NE 11 « cc ‘“ SW 17 yt 
bs 73 E t 3 “gs “ce W 204 ie 
Total land winds, 80 “ Total sea winds, 285 “ 
It may be well to explain that the northwest and southeast 
winds blow in a line with the coast, and are classed, the former 
as land winds and the latter as sea winds, not so much from their 
irection as their sensible qualities. dies sar 
a 
