The following Table contains the difference between the time of high water at Boston, and at a large number of places on the American coast, by which the time at any of them may be easily ascertained, by subtracting the difference at the place in question from the time at Boston, when the sign is prefixed to it; and by adding it, when the sign is +.

The time of high water, in the calendar pages, is of that tide which immediately precedes the southing of the Moon.

DARKNESS OF THE NIGHTS DURING THE YEAR 1845.

For Boston, New York, Philadelphia, Washington, &c.

The number of hours at the top of the page denotes the average time for the month from the end of evening twilight to the beginning of morning twilight.

The dots in the table denote the hours of entire darkness, when there is neither sun, moon, nor twilight, and their disposition denotes the hours before or after midnight.

Days of

Month.

January Feb'y March April May Jun. July Aug. Sept. Oct.
8 h. 7 h. 5 h. 6 h. 7 h. 8 h. 9 h.

12 h. 11 h. 9 h.

DARKNESS OF THE NIGHTS DURING THE YEAR 1845. For Charleston, New Orleans, &c.

h. m.

h. m. h. m.

Twilight begins and ends. Mean time.

7th day. Begins. Ends Begins. Ends. Begins. Ends. Begins. Ends.

13th day.

19th day.

25th day.

h. m.

h. m.

h. m. h. in.

h. m.

Boston,

Sun's upper limb rises and sets, (corr. for refract.) M. T. || High Water.

M. time.

Full Moon,

Last Quarter,

30th

23d day, 9h. 12.1m. M 8 47.4

A.

5 Su. 7 30 4 42 7 25 4 47 7 19 4 53 7 3 5 8 6 53 5 14

EN. Orleans,

&c.

sets.

3

3

7

6 57 12
57

12

3

7 58 13

3

3

3

12 Su. 7 29 4 49 7 24 4 54 7 18 5 0 7 3 5 14 6 58 5 19

19 Su. 7 25 4 58 7 20 5 2 7 15 5 7 7 2 5 20 6 57 5 25

14

8

14

9

5 13 10

12 12

8 53a

6 38a

4 58a

20 56

26 10 1

7 41

6 1

21

56

27

10 43

8 28

6 48

0

26 Su. 7 20 5 6 7 15 5 10 7 10 5 15 6 59 5 26 6 54 5 32