In former times men believed that the Earth was flat, or a circular plate on all sides surrounded by water. But this is not true. For it has been proved by a great many observations and actual measurements, that the Earth has a spherical (ball-like) form. Moreover there are navigators who have actually sailed round the world, and who have noticed the fact that at sea, the tops of distant objects are seen sooner than the rest; which again proves the spherical form of our Earth. For an illustration you may look at the adjoining plate Plate No. [I].
The man who is represented as standing on a portion of our Earth, will at first only see the topmast of a vessel at sea; when she comes nearer his eye will discover a much greater portion of her; but when in the third position every part of the vessel will be visible.
§ 5. Some of the Planets are, in their motion round the Sun, accompanied by other dark bodies, which, like the Planets themselves, receive light and heat from the Sun. These are called Satellites or Moons. Such a Satellite is the Moon which accompanies our Earth; and there are Planets (as we shall see hereafter) which have Four and Six, and One that has even Seven Moons.
§ 6. Besides the Planets and Moons there is yet another class of bodies, moving round the Sun in exceedingly long ovals. They are but seldom visible, and are distinguished from other heavenly bodies by a tail which is often three, four, and more times larger than the body itself. These are called Comets; but their number has not, as yet, been precisely ascertained.
§ 7. The Planets, Moons and Comets, together with the Sun around which they move, form what is called our Solar System. But what will you say, if you are told that each fixed Star in the firmament is a Sun which, like our’s, has its Planets and satellites and Comets; in short, that each fixed Star is the centre of a solar system, a thousand and more times larger than our own!! But how infinitely great must God’s Creation appear to us, when we reflect that all these globes, as well as our own, may be inhabited by reasonable beings!!!
No. I.
RECAPITULATION OF LESSON I.
[If the pupil has learned and understood this lesson, it may perhaps be not unreasonable to suppose he will like to know something more about the Planets and the Moons in our system. But the teacher ought not to allow him to enter upon the second lesson, before he has recapitulated the first.]
QUESTIONS.