The Study of Astronomy, adapted to the capacities of youth / In twelve familiar dialogues, between a tutor and his pupil: explaining the general phænomena of the heavenly bodies, the theory of the tides, &c.

by teacher of astronomy John Stedman

Pupil. Certainly.

Tutor. And does it not move in a strait line?

Pupil. At first it appears to do so; but afterwards it inclines towards and falls to the earth.

Tutor. Cannot you account for this?

Pupil. I suppose it must be drawn to the earth by attraction.

Tutor. You are right. The attraction of the earth, and the resistance of the atmosphere or air through which it moves, retards its progress, or it would continue moving in a strait line, with a velocity equal to that which was at first impressed upon it. In like manner the beneficent Creator of the Universe impressed a force on all the planets which should be equal to that of the attractive power of the sun, that one might not overcome the other.

Pupil. This wants explaining.

Tutor. I would willingly gratify you, but as I have much more to say on the subject, I fear it will be too great a burthen on your memory; it will therefore be better to postpone it.

Pupil. As you please, Sir.

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