Month D

H MAPM

NOT ANDA.

1831 O Feb.

12

1832 Feb.

1

July

1833 D Jan,

1834 June 21

3 13 AM Total.

Nov.

30

Dec.

2 38 PM Total. 15 11 50 PM

1835

5 10 PM Visible in the W. part of the

732 PM About total.

Charleston, S. C.*

Those with the asterisk are inserted from the American Almanack, 1830.

8 22 A M Visible in Mo. Ter.

13 6 29 PM Total.

4 32 P M Annular in Virginia.

[Union

1839

What day and hour in 1831 will there be an annular eclipse? Where? When will there be another total solar eclipse in the United States? Where?

1853 D Jan. 1854 Nov.

21 1 3A M Small.

NOTANDA.

4 4 22 P M Very small. Visible in N. E. 6P M Total.

1 11

1855 D May DOct.

1865 D April DOct.

Oct.

1866

10 11 29 P M Very small.

4 5 50 P M Very small.

19 10 27A MAnnular at Wilmington, S. C.*

March 40 11 30 P M Total.

5P M Total over a southern section [of the Union.

1871 D Jan.

1872 Nov.

15

0 29 A M Very small.

1873 D May

12

6 4 9P MMoon rises partially eclipsed.

6 23 A MCom. 4h. 34'.

[w. s. Total in the

The remainder of the eclipses for the 19th Cen tury, as seen at the CAPITOL, may be given sum marily, thus: In the Years 1885, 1886, 1889, 1892, 18 37, 1900, there will be solar eclipses; in 1886 two. The lunar eclipses will be 18 in number, 6 of which will be total.

No total solar eclipse is calculated for the capital of France in the nineteenth century. The eclipse of 1906 which has been described, as so intensely interesting a scene in New-England, was but about 4 Digits eclipsed at Paris. The only annular eclipse there this century, will be in 1847.

CHAPTER XIII.

DAY AND NIGHT.

THE vicissitudes of light and darkness, heat and cold, are so familiar to us, that we think little of their recurrence. But WISDOM and BENEVOLENCE are eminently conspicuous, in the admirable simplicity of their causes. The Sun and the other celestial bodies, appear to rise in the east, and set in the west. This apparent motion in them, is caused by the real motion of the earth on its axis. A trifle more than one rotation constitutes a day, because of the Earth's motion round the Sun. Three hundred and sixty-six rotations are required to give 365 days. About the 20th of March and the 23d of

Is any total solar eclipse computed for Paris this century? When will an annular one occur there?

What is the apparent daily motion of the heavenly bodies What occasions it? How many rotations of the Earth in 365. days? Why?

September, were we under the equator we shoul at noon see the Sun vertical, or directly over heal. Then the northern and southern hemisphers would be egy illuminated, and the days aid nights would re equal in length quite over tie Globe. For this reason these periods are caled equinoxes.

If the Equator coincided with the Ecliptic, is seen in Plate v. Figure 1, there would be no vaiation in the length of days, and no change of stasons. But these make with each other, an angle of 23° 25'; consequently from the vernal equinox in March, till about the 20th of June, which is called the summer solstice, the Sun appears to advance to the north: still at the Equator the Sun will be twelve hours above, and 12 hours below the horizon. But north of the Equator, it will be more than 12 hours above the horizon; at the Arctic pole 6 months; at the Arctie circle from 12 to 24 nours.. In Latitude from 40° to 430, the longest days will be from 15 to 15 hours. The Sun will appear to rise in the north east, and set in the north west. The twilight will be seen till 9, P. M. and by 3, A. M. In the 60th degree of Latitude, the Sun will be 18 hours above the horizon, and the twilight will not cease to be visible. At midnight its place will be due north.

When the days are longest, the nights of course will be shortest. The vicissitudes in the length of the days in the southern hemisphere will be similar, but in the other, six months.

When do the equinoxes occur? Why called equinoxes? What occasions the inequality in the length of days? What is the greatest length in the days at the Equator ?-between 40° and 430 of north Latitude ?-at the 600 ?-between the Arctic circle and the pole ?

The Instructer can further illustrate this subject from Plate v. Figure 2,or from a terrestrial Globe rectified to the Latitude where he is.

At the ring and setting of the Sun, rays of light and rays of caloric fall nore obliquely than at mid-day, consequently they have the greatest power at noon. But the earth has accumulated heat from the Sun's influence, which is radiated between 13 and 3 o'clock to such a degree as to render it warmest usually about 2 o'clock.)

2

THE SEASONS.

Theinclination of the axis of the Earth causes the Sun not to shine on one part of its surface, for months. This portion of the Earth is called a frigid zone. One half of each year, the Sun's rays are excluded from almost 2340, round the north pole, and the other half of the year, from the same extent round the south pole; consequently there are two frigid zones.

That portion of the Earth, which receives the rays of the Sun in a vertical, or perpendicular direction, is called the torrid zone. This zone extends 23°28′ each side of the Equator, making almost 47° in breadth. '

(The portions of the Earth, which are enlightened every day in the year, but where the Sun's rays are never vertical, are called temperate zones. The whole number of zones is five; one torrid, two temperate, and two frigid zones."

The circles which bound the torrid zone are called tropics, the one north of the Equator, is the tro

How can this subject be well illustrated? How do the rays of the Sun fall morning and evening? What effect resulta from this fact? What hour is the warmest?

On

What causes the disappearance of the Sun for months? what parts of the Earth is this witnessed? What are they called? What makes the torrid zone?

How broad is it?

Where are the temperate zones? How many zones?