94 51

6 1811 25 11 50

6 40 0 6 0 29

1 20

9 26 2 5

9 54 2 40

25 Fri 20 43 197 26 Sat 20 54 597 94 51 27 B 21 6 157 104 50 7 18 0 46 28 Mo 21 17 77 114 49 8 16 29 Tu 21 27 357 124 48 30 We 21 37 387 134 47 Ephemeris of the Planets for the First, Tenth and Twentieth days of Month. [Calculated for the Meridian of San Francisco.]

6 57 5

3

6 14

7 324 28

6 28

6 57 5

3

6 36

7 334 27

6 50

1 9

6 585

2

SAN FRANCISCO.. First Qua'r.. 2 5 40 mor. Last Qua'r..16

..Full Moon..
.First Qua'r.. 2
.Full Moon.. 9
.First Qua'r.. 2
.Full Moon.. 9

Ephemeris of the Planets for the First, Tenth and Twentieth days of Month. [Calculated for the Meridian of San Francisco.]

II. LATITUDE AND LONGITUDE.

LATITUDE AND LONGITUDE

Of the Principal Points on the Pacific Coast, determined by George Davidson, U. S. Coast Survey.

NOTE.-Primary astronomical stations in SMALL CAPITALS; the series of observations at these sta

tions extend through not less than two or three lunations. Positions determined by trigonometrical connection with astronomical stations, in Italics. All other determinations by chronometric connection with primary astronomical stations for longitude, and independent observations for latitude. The localities of the astronomical stations and observatories can be more definitely determined by reference to the published maps, etc.

III.-TIDES AT SAN FRANCISCO, CAL.

[By Prof. A. D. Bache, Superintendent U. S. Coast Survey.]

Besides the ordinary changes in the time and hight of the tides known to all navigators, it is important to note the following, generally applicable to the Western Coast, and particularly to San Francisco Bay. They relate to peculiarities in the tides which occur on the same day, the necessity for knowing which is shown by the fact that a rock having three and a half feet of water upon it at low tide, may, on the same day, at the succeeding low water, be awash:

1. The tides at Rincon Point, in San Francisco Bay, consist generally of a large and small tide on the same day; so that of two successive high waters in the twenty-four hours, one is much higher than the other, and of the two successive low waters, one is much lower than the other.

2. The difference in hight of two successive tides, either high or low waters, varies with the moon's declination. When the declination is nothing, the difference is nothing or very small. When the declination is greatest, whether North or South, the difference is greatest. When the moon's declination is nearly nothing, the intervals between two successive high, or two successive low waters, are nearly twelve hours, and differ most from this when the moon's declination is greatest.

3. The inequalities in the hights of successive low waters are more considerable than those of successive high waters; while, on the contrary, the inequalities in the times of high water are more marked than those of low.

4. The average difference between the hights of two successive high waters is one foot four and a half inches, and of two successive low waters two feet four inches. The average difference of these same hights, when the moon's declination is greatest, is for the successive high waters two feet, and for the low waters three feet six inches.

5. The average variation from twelve hours, in the interval between two successive high waters, is three-quarters of an hour, and between two successive low waters, half an hour. The average variations of the same intervals when the moon is furthest from the Equator, are, respectively, one hour, and three-quarters of an hour.

6. When the moon's declination is North, the higher of the two high tides of the twenty-four hours is the one which occurs about eleven and a half hours after the moon crosses the meridian; and when the moon's declination is South, the one which occurs about one and a half hours after the moon's meridian passage.

6. Bis. Or, the following rule may be used, which applies when the moon crosses the meridian between midnight and 11 A. M., or between noon and 11 P. M.

If the moon is South of the Equator and passes the meridian in the morning, the high water will be higher than the afternoon high water; if it passes the meridian in the afternoon, the afternoon high water will be the higher. If the moon is North of the Equator, and passes the meridian in the morning, the afternoon high water will be the higher.

7.

The lower of the two successive low waters of the twenty-four hours, occurs about seven hours after the higher of the two high waters.

8. The average difference between the hight of the higher high water and of the lower low water, is five feet eleven and a half inches, and the greatest difference is seven feet ten inches.

The above rules were drawn up so as to avoid technical terms.

IV. METEOROLOGICAL OBSERVATIONS,

MADE AT SAN FRANCISCO, FROM JANUARY, 1851, TO JANUARY, 1858.

[By Henry Gibbons, M. D.]

Most of the subjoined tables explain themselves sufficiently. Those relating to rain being of the greatest interest and importance to California, are given in detail. Table 6 shows every rain that has fallen since 1850. December appears to have been the most rainy month, but there is one day, the 8th of December, on which no rain fell in the entire period of seven years. A marked abatement of rain is observable from about the middle of January to the middle of February. One-third of the average yearly rain falls before the first of January, one-third in January and February, and the remaining third subsequent to the first of March. March and April supply nearly as much rain as any other two months. In 1853, there was nearly five inches in April, and in 1855 upwards of five and a half inches. In the latter year more than two inches fell in May.

1. TABLE OF MEAN TEMPERATURE,

Showing the Mean Temperature of each Month at Sunrise and at Noon, and the Mean of the extremes for each Month, from 1851 to 1857, inclusive; also, the Mean Temperature for each Year.

Mos.

Sunrise.

Noon.

Mean of Extremes.

1851 1852 1853) 1854|1855) 1856 1857 1851 1852 1853 1854 1855 1856 1857 1851 1852 1853 1854 1555 1856 1857 J41 7 44 6 47 6 42 344 7 43 4 45 7 56 957 056 5 64 2 57 354 156 7 49 350 852 0 48 2 51 0 48 8 51.2 F42 045 7 48 247 9 50 347 346 1 60 0 60 4 60 159 263 3 60 1 56 661 053 154 153 6 56 8 53 7 51 4 M44 0 45 2 49 6 47 251 8 479 49 1 63 7 60 7 62 161 067 063 962 7 53 8 52 955 9 54 1 59 4 55 955 9 A 48 2 45 451 7 51 150 648 7 51 4 67 3 65 461 8 68 464 963 1 66 157 7 55 458 359 8 57 7 55 958 8 M 49 6 47 853 4 49 0 50 1 49 350 5 64 3 62 3 68 0 64 664 463 3 64 657 0 55 1 60 7 56 8 57 7 56 357 5 J50 951 952 750 1 52 0 50 953 4 66 7 68 971 166 867 967 368 558 860 461 958 459 959 1 61.0 J51 5 53 152 551 951 952 052 664 3 69 7 68 1 70 667 566 865 757 9 61 460 361 361 2 59 4 59 2 A 55 053 6 52 9 52 455 3 52 952 5 69 4 68 7 67 0 68 369 666 3 65 662 261 260 060 462 5 596 59·1 S54 052 9 55 1 53 355 053 952 5,69 373 470 2 67 769 969 169 061 663 1 62 760 562 461 5 60 7 053 450 054 653 354 850 152 670 467 470 9,68 168 365 1 68 761 958 762 760 7 61 6 57 6.60 6 N53 449 850 95) 746 6 47 4 46 6 63 6 61 363 0 65 1 59 259 3 62 556 355 557 057 952 9 53 3 54 5 D46 146 246 747 0 43 3 42 0 42 9,56 6 55 4 57 460 752 252 0 56 251 350 852 153 8 47 8 47 0 49 5 M48-848-951-349-750 849 350.564 4 64 264 9 64 664 462 663 656 656 558 157 157 6 56 0 57'0

2. TABLE OF CLOUD AND MIST FOR 1857,

Showing the proportionate Time in each Month when the Sky was Clear and Cloudy, given in Days; the number of Days when the Sky was Clear, from Sunrise to Sunset, and the number Cloudy; the number of Days on which Rain fell, and the number of Days on which there was more or less Mist.

10 9 7 12 Aug. 19 12 6 0 0 13 15 4 Sept. 21

71 11

8

9 11 1

7

7 Oct.. 23 8 12

6 Nov. 19 11 17
20 11 14

13980

10 Dec

13

89