3. TABLE OF WINDS FOR 1857.

The direction of the Wind is noted three times a Day, so that three Observations in the Table are equal to one Day. The proportion of Land Winds and Sea Winds is given in Days, the Land Winds being from N. W. to E., and the Sea Winds from S. E. to W. The number of Days when the Wind was high is given in the last Column.

N. N. E. E. S.E. S. S. W. W. N. W. Land. Sea. High.

August.

83

September

October...

3

November

7

December.

18

2249

3

78

20

22

27

27

27

31

31

28

6

25

22 11 19

6722

4. TABLE OF EXTREMES OF HEAT AND COLD, Showing the greatest degree of Heat and the greatest degree of Cold in each Month, from December, 1850, to July, 1858.

1858. Max Min. Max Min. Max Min. Max Min. Max Min. Max Min. Max Min. Max Min. Max Min.

71 45 67 41 81 47 75 43 87 40 78 49 80 49 87 50 74 47 82 49 74 46 87 50 77 44 73 47 79 49 78 51 87 46 90 51 78 48 72 50 86 48 82 50 76 49 76 51 85 50 79 53 80 49 83 50 75 50 98 45 88 50 87 46 84 50 85 51 93 50 83 47 78 46 85 49 83 46 79 51 79 41 83 45 73 41 80 40 73 44 72 47 67 42 74 40 72 31 Dec. 64 28 61 35 63 36 69 40 71 38 61 29 58 35 60 34

84 30 98 35 88 40 87 25 90 29 85 33 93 31

In

From the foregoing table it appears that the greatest degree of cold at San Francisco, in seven years, was twenty-five degrees, or seven below the freezing point. This may be set down as nearly the extreme cold ever felt here. three of the years the mercury did not fall to the freezing point. In 1853 the lowest point was eight degrees above freezing.

The extreme of heat was ninety-eight degrees-a very unusual temperature for San Francisco, though much below the greatest heat in the interior. In 1856 the highest temperature was eighty-five, and in 1851 the thermometer did not rise above eighty-four.

5. TABLE OF COMPARATIVE RAINS,

Showing the amount of Rain fallen at stated times, in every Rainy Season from 1850 to 1858; four stated Periods in each Month being given.

May..7 6.32 18.68 32.37 21.94 22 13

66

..23

แ

..31

..15 6.32 18.68 32.65 21.94 23.87 7.01 18.98 32.65 21.94 24.27 20.63 20.20 21.81 20.94 7.01 18.98 32.69 21.94 24 27 20 71 20 22 21.81 20.95

19.87

20 20

21 47

20 87

6. TABLE OF DAILY RAINS,

Showing the Date and Amount of every Rain from Summer of 1850 to Summer of 1858. Date 1850 1851 1852 1853 1854 1855 1856 1857 To'l Date. 1850 1851 1852 1853 1854 1855 1856 1857 To'l

Date. 1850 1851 1852 1853 1854 1855 1856 1857 To'l Date. 1851 1852 1853 1854 1855 1856 1857 1858 To'l Nov21

3

Feb15

2

1853 1854 1855 1856 1857 1858

انا

12345678

2

21

TOTALS.-In 1851, 7·11 in; '52, 17·98; '53, 33·12; '54, 22:04; '55, 24'02; '56, 21-73; '57, 18:00; '58, 1905.

7. TABLE OF MONTHLY RAINS,

Showing the Amount of Rain, in inches, in each Month, from the Autumn of 1850 to the Summer of 1858; also, the mean quantity for each Month of the Year in that period.

1851.

1852. 1853. 1854. 1855. 1856. 1857. 1858. Mean.

65

⚫35

April May. June

1.14

58 4.11 4.27 4.52 8.44 207 4.36 3.63 12 1.16 8.41 4.64 43 8.66 1.32 3.14 1.88 6 40 4.81 3.17 4.31 1.64 1.56 3.94 3.46 19 5 05 3.31 5.59 3.14 00 1.14 2.46

July.

August

September..

October.

V.—CONTRIBUTIONS TO THE CLIMATOLOGY OF CALIFORNIA.

BASED UPON FIVE YEARS' METEOROLOGICAL OBSERVATIONS AT SACRAMENTO.

[By Thos. M. Logan, M. D.]

THE physical features of California present every diversity of character, and this difference of conformation is a powerful cause of the variety of climate met with within its area. As a whole we cannot speak intelligibly of its climate, as we do of that of Cuba, or of our Southern, Middle, or the New England States, for it has many climates, anomalously distributed in abrupt contrast, and setting at naught our accepted notions of the effects of latitude and altitude.

In no other portion of the globe, therefore, are the requisite facts and statistics of meteorology more absolutely necessary than here for a correct understanding of the climatology. When the measures of heat, rain, wind and other conditions necessary to make up our knowledge of what is understood by the word "climate," are determined in a sufficient number of stations, we may then, by a comparison of these facts, and from the relation they bear to each other, reach inductively the processes by which the combinations and varieties are formed. As subservient to this end, the accompanying results of observations made at Sacramento have been prepared. The statistics of greatest value in climatology are the monthly summaries of the measurements of the conditions just referred to, giving the averages, or the fixed quantities, and these we have compressed into the smallest possible compass, in tabular form, purposing, when treating on any special subject to which they appertain, to comment thereon textually.

The results are most of them calculated from five years' observations made in accordance with the uniform system adopted by the Smithsonian Institution, at 7 A. M., 2 P. M., and 9 P. M.; and although the period is too short to meet the rigid exactions of meteorological science, in deducing positive conclusions, still an approximation may be arrived at that will be sufficiently near to afford a very just appreciation of the climatic features of that great valley, which constitutes, what may be topographically considered, the middle portion of California, and of which the city of Sacramento is the center.

Viewed in connection with the reports furnished for this annual by Dr. Henry Gibbons, of San Francisco, we have now the types of two of the grand divisions of California. As soon as results are obtained from that third general division of the State-the slope of the Sierra chain, which binds our great valley on the east-we may then be enabled, by comparison and contrast, to form some idea of the subordinate local differences of climate, than which, owing to peculiar local configurations, a more confused variety is hardly to be imagined.

Considered in a general manner, we would pronounce the climate Asiatic; and this expressive designation, which Fremont has applied also to the great basin and arid plains west of the 100th meridian, is particularly applicable during the summer months, when the number of hours of increasing heat considerably exceed those of radiation.

At this season the surface humidity is too little to retard the accumulation of heat from the sun's rays; consequently the afternoon temperature frequently becomes, for a short time during the day, as great as that of districts ten or twelve degrees further south on the Atlantic side-the absence of clouds, owing to the same cause, which creates the cessation of rain, (deficiency of moisture and insufficient coldness of the earth to condense what little there is,) facilitating both processes.

The temperature of evaporation gives the instrumental proof of this great measure of dryness. The difference between the temperature of the wetbulb thermometer and that of the air is often 200 during the hottest part of the day for several successive days, and not unfrequently reaches 250 and 30°. The most striking Asiatic feature, however, is found in the great reduction of temperature after the maximum is reached. However high the wave of temperature towers up under the influence of a vertical sun and cloudless sky, it sinks proportionately low during the night, rendering it cool and chilly. Upon examination of the record of our thermometrograph, the variation between the maximum and minimum observation is frequently found to be as much as 250 and 30°; and the mean daily range for the five warmer months, May to September, during the last two years, amounted to 190 68. The following table exhibits the mean daily range for each month during the years 1856 and 1857:

THERMOMETROGRAPH. Mean of all highest readings by day..

Mean of all lowest readings by night...

Jan. Feb. Mar. Apr. May. June July Aug. Sept. Oct. Nov. Dec. An'l.

51 3257 38 63 56 68 22 71 30 79 20 78 9581 03 78 99 67 75 59 41 50 64 67 29

39.81 43 72 47 91 50 01 53 35 58 88 58 88 64 69 55 45 49 86 43 64 37 80 50 33 Mean daily mensu'l range 11 51 13 66 15 65 18 21 17.95 20 32 22 07 16 34 23 54 17 89 15 77 12-8416-96

As far as our information extends, this remarkable diurnal range of temperature appears to be a characteristic feature of all the great valley regions and plains of the State; in fact, we may say of all the Pacific and interior arid climates, irrespective of altitude, with the exception of the immediate coast district. All the officers of the U. S. Surveys have remarked it. At Fort Yuma, on the west bank of the Colorado, lat. 32° 43′ 00′′, and 120 feet above sea-level, it is, according to the U. S. Army Meteorological register, from 200 to 300 for the summer months. At parts of the greatest elevation, as Fort Defiance, altitude 7,200 feet, and Fort Union, altitude 6,670 feet, the range is still greater, sometimes attaining 350. It is still great at Fort Snelling, and at all points on the dry plains, while at San Francisco, the representative point of the Pacific coast climate, it is about 100 only, less even than at New York city on the Atlantic.

In reference to the adaptation of cultivated plants and agricultural staples to this climate, we would here apply the remarks of Blodgett, viz.: that the