We should look upon ourselves as such. What ought we to do?

To promote, as far as we can, by our plans, words, contributions, services, and prayers, the diffusion throughout all lands of the light and blessings which we enjoy.

69

CHAPTER III.

ASTRONOMY.

I. A GENERAL VIEW.

REPEAT the first verse of the 19th Psalm.

"The Heavens declare the glory of God,

And the Firmament sheweth His handy Work."

What do you mean by His glory?

His attributes, or perfections.

Mention some of them.

Wisdom, power, goodness.

Of what does the visible universe consist?

Of various globes, or orbs.

Mention them.

The Sun, Planets, Satellites, Comets, and Fixed Stars. What do you call that part of the universe in which we are? The Solar System.

What is a System?

A Whole formed by the combination of parts related to each other.

Why do you call this System the Solar?

Because the Sun, by which it is lighted and influenced, is its centre.

What other systems are there?

The Sidereal, or starry systems.

Is this only one system?

It may be composed of numberless systems.

What does this fact present to your mind?

An overwhelming idea of the Creator and of Creation.
Of how many bodies does the solar system consist?
Of thirty-one, including the sun.

How do

you divide these bodies?

Into Primary and Secondary.

How many are the Primary, omiting the sun?
Twelve.

Mention their names.

Mercury, Venus, Earth, Mars, (Vesta, Juno, Ceres, Pallas,)
Jupiter, Saturn, Uranus, Neptune.

What do you say of these bodies, in relation to the sun?
They move round the sun, at different distances, and
receive light, &c. from him.

How many are the Secondary bodies.

Eighteen.

What are these called?

Satellites.

What do you say of them, in relation to their Primaries? They move round their primaries, and are carried with them round the sun.

What are the primary bodies called?

Planets; Wanderers.

Why are they so called?

Because they move in Orbits, or Paths.

What follows from this?

They are continually changing their places in the heavens, with respect to each other, and to the fixed stars.

Describe their paths.

They move round the sun in the same direction as the

earth does, in paths, nearly circular, but somewhat elliptical or oval.

What sort of bodies are they?

Opaque; not transparent; receiving and reflecting light; not luminous in themselves.

Were any of them discovered lately?

Uranus was discovered by Herschel in 1781; Vesta, Juno, Ceres, and Pallas early in this century; Neptune in 1846.

Are these seen by the unaided eye?

No: only by means of a telescope.

Where do the paths of Vesta, Juno, Ceres, and Pallas lie?
Between the paths of Mars and Jupiter.

Where does the path of Neptune lie?

Beyond the path of Uranus.

What are the planets supposed to be?

Worlds; perhaps much like our Earth.

Mention the primaries which have satellites.

The Earth has one, the Moon; Jupiter four; Saturn seven; Uranus six.

Lay down the solar system, omitting the telescopic planets. 1. The Sun in the centre.

2. Mercury, next to him.

3. Venus next.

4. The Earth next, with one satellite.

5. Mars next.

6. Jupiter next, with four satellites.

7. Saturn next, with seven satellites.
8. Uranus next, with six satellites.

What other bodies belong to the solar system?
Comets.

What are these?

A sort of planets, of which but little is known.

In what sort of paths do they move?

In immensely elongated ellipses; some perhaps in parabolas or hyperbolas.

What is their number?

It is not known: it must amount to several hundreds.

What is the meaning of the word Comet?

It comes from a Greek word signifying "Hair."

What is the appearance of a comet?

A splendid mass of light, like a star or planet, with what is commonly called a "tail."

What is this tail?

A luminous train preceding, or following, or surrounding the nucleus, or bright orb.

Of what does the Sidereal system consist?

Of what we call the Fixed Stars.

Why are they so called?

Because they do not change their places in relation to each other.

How are they distinguished into classes?

By their Magnitudes: first, second, &c., to the sixteenth. Are they visible to the unaided eye?

They are so, to the sixth or seventh magnitude.

How many stars are registered to the seventh magnitude inclusive.

Between 15000 and 20000.

How many may be seen by the unaided eye in a clear winter

night?

About a thousand.

What is the distance of the stars from us?

It cannot be so small as the earth's radius, 4000 miles

multiplied into 4,800,000,000.

What would be the amount of these numbers when multiplied?

More than nineteen billions of miles. [19,200,000,000,

000.]

What do you say of such a number and of such a distance?

The imagination is quite lost in them.

Give a notion of the distance of the stars from the velocity of light.