“Shiver and shrink at sight of toil and danger,
“And make the impossibility they fear.”
Pupil. This gives me encouragement, and, if you will have patience with me, I will endeavour to profit by your instructions.——Pray, Sir, what is the sun?
Tutor. The sun, the source of light and heat, has been considered a globe of fire, round which seven other spherical bodies revolve at different distances from him, and in different periods of time, from west by south to east. These are the planets[[1]].
Pupil. Any round ball is a globe, is it not?
Tutor. A sphere or globe is defined a round solid body, every part of whose surface is equally distant from a point within called its center; and a line drawn from one side through the center to the opposite side, is called its diameter.
Pupil. You say the sun has been considered a globe of fire. Is he not now thought to be so?
Tutor. [[2]]Doctor Herschell, from some late observations, is of a different opinion.—But what think you of his magnitude?
Pupil. I really cannot conjecture.—This I know, that when I saw him through the fog the other day, he appeared about the size of a common plate.
Tutor. You must not always judge by appearances. You will find that there is a material difference between his real and apparent magnitude, which I think you will be convinced of when I tell you, that he is no less than 95 millions of miles from our earth.