248 
BAROMETRIC OBSERVATIONS. 
OBSERVATIONS—Continued. 
Station. 
Date. 
Hour. 
No. of barometer. 
First reading. 
Attached thermome¬ 
ter. 
Air thermometer. 
Reading corr. for con¬ 
stant error, temp, 
andhor. variation. 
Corrected mean ba¬ 
rometer reading. 
Wind. 
Clouds. 
. 
£ 
.2 
o 
9 
s 
<6 
o 
'r-> 
o 
1853. 
Station 3.. 
Dec. 13 
3. 25 p. m. 
783 
24. 808 
53 
24. 787 
Bivouac 1.. 
Dec. 14 
Sunrise.... 
783 
24. 616 
30. 3 
24. 556 
Bivouac 2, mouth 
Dec. 15 
Sunrise_ 
783 
25. 085 
22 
25. 038 
Cirrus, 3 
of Canon Diablo. 
Station B. .. 
_do_ 
12. 30 p. m. 
783 
24. 754 
34. 5 
24. 710 
1. 30 p. m. 
783 
. 826 
47. 5 
. 788 
Nim. & cum., 9 
Bivouac 3. 
-do_ 
Sunset_ 
783 
24. 386 
34. 4 
24. 387 
Do.. 
Dec. 16 
Sunrise_ 
783 
. 480 
13. 7 
9 a. m_ 
783 
.497 
26 
. 441 
Station 3, top of 
_do_ 
783 
23. 858 
45 
23. 754 
volcanic peak. 
Station 4—valley. 
_do_ 
10.30 a. m. 
783 
24. 320 
37. 5 
24. 230 
Cirrus, 1__ 
Bivouac 4_ 
_do_ 
783 
23. 586 
40 
23. 570 
N.W. 
1 
Sunset_ 
783 
. 574 
34. 5 
Cirrus, 1_ 
Do.. 
Dec. 17 
Sunrise_ 
783 
. 591 
29. 6 
. 588 
Station 1_ 
_do_ 
10 .10a. m _ 
783 
23. 389 
44. 7 
Station B. 
_do_ 
11 a. m_ 
783 
23. 222 
44. 2 
23. 108 
Station C_ 
_do_ 
783 
23. 330 
48. 3 
23. 146 
Station 8_ 
....do.... 
783 
22. 486 
55. 2 
22. 452 
Biv. 5, Leroux'sSp. 
_do_ 
783 
22. 920 
54. 7 
22 . 881 
Sunset_ 
783 
. 900 
36. 5 
. 894 
Do_ 
Dec. 18 
Sunrise_ 
783 
. 835 
«21. 7 
.795 
Cirro-strat., 2. 
Station 4_ 
_do_ 
3 p. m_ 
783 
23. 180 
47. 5 
23. 159 
Bivouac 6. _._ 
_do_ 
Sunset_ 
783 
23. 107 
39. 7 
23. 100 
N.E_ 
3 
Cirrus, 2_ 
Do_ 
Dec. 19 
Sunrise_ 
783 
. 092 
40. 3 
. 014 
S.E_ 
1 
Stratus, 9._ 
Bivouac 7. Cosnino 
_do_ 
Sunset_ 
783 
23. 926 
32. 5 
Cirrus, 7_ 
caves. 
Do. 
Dec. 20 
Sunrise.... 
783 
. 913 
31. 3 
_ 
. 896 
w.s.w. 
2 
Cirro-strat., 2. 
_do_ 
Sunset _ _ 
783 
25. 330 
0 
Cir.-cum., 5. _. 
Camp 91, Leroux’s 
Dec. 28 
9 a m_ 
783 
23. 062 
46. 8 
22. 964 
0 
Cirrus, 3_ 
Spring. 
Top of Hill D 
_do_ 
11.50 a. m. 
783 
22. 141 
48. 7 
22. 051 
783 
. 113 
44. 7 
. 090 
_do_ 
2. 30 p. m. - 
783 
22. 846 
56. 7 
22. 814 
_ 
_do_ 
3 p. m_ _ 
783 
22. 964 
22. 952 
_ 
Do. 
Dec. 30 
9. 35 a. m 
783 
. 988 
32. 5 
. 902 
w . 
1. 5 
_do_ 
Sunset_ 
783 
22. 977 
32. 6 
22. 986 
0 
Do 
Dec. 31 
Sunrise_ 
783 
. 938 
27 
. 917 
783 
23. 116 
51. 5 
. 993 
s . 
2 
Cirrus, 1. 
do 
783 
23. 113 
49. 8 
22. 977 
. 
o The thermometer at the r 
iver indicate! 
1 colder weathe 
r in tl 
e valle 
y than \ 
vas found 2,000 
feet hie 
;her among the 
mountains, being at this time 8°.5 Fahrenheit. The reverse occurs during the middle of the day, it being the warmer in 
the valley, showing that the thermometer has a less daily range in the mountains than in the lowlands. The high grav¬ 
elly mesas and ridges probably absorb more heat by day and radiate more at night than do the clayey bottom lands. 
December 14.—At 7.30 p. m., a bright coronas of variegated colors encircled the moon; slight snow at 8 p. m.; cumulus 
clouds at 8.30 ; appearance of more snow. 
December 15.—The morning clear and calm, the San Francisco mountains being free from clouds and clad in snow; soon 
they were crowned in mist, which spread and quickly brought a snow-storm; shortly this passed over and was succeeded 
by several similar phenomena ; an inch of snow fell during the day. In the evening, clouds that had heretofore travelled 
eastward, were flying towards the southwest, and at 9.30 p. m. not a vestige of them could be seen, excepting a fringed 
bank which rested upon the loftiest of the mountains in front; at 8 p. nr. bright coronee around moon ; the atmosphere 
beautifully serene and brilliant. 
December 16.—At 9 a. m., hazy. At 9 p. m., light green halo around moon. 
December 17.—At sunrise a breeze came from the east, and the atmosphere rvas pure and transparent; the day fine ; the 
sun warm enough to effect a slight depression of the snow, which lies upon the hills and valleys to a depth of about eight 
inches. Clear during the day. 
December 18.—The sky before sunrise was variegated with cirro-stratus clouds, producing an imperfect halo, 22° diam. 
around the moon; ice an inch thick covered the rivulet in the valley. The spring itself was not frozen; at 12 m., 
clouds, cirrus 7 ; wind southeast, 5 ; at 1 p. m , wind west, 5 ; clouds moving north 60° east. The sun during the day 
dimmed with cirrus clouds ; the night clear. Sunset, clouds moving southeast; night clear. 
December 19.—'The evening calm and clear. 
December 20.—Sunrise, clouds moving east. 
December 28.—The day clear and pleasant; the night somewhat cloudy, threatening rain. 
