Page:The fairy tales of science.djvu/211



us take our station, on a clear evening, in some wide, open plain, and gaze upward and around on the star-spangled heavens that shroud and reveal—reveal and shroud—the unfathomable mystery of the and. Though from the spot we occupy in space we can see only a small portion of the visible universe, yet even with the naked eye we behold a multitude of bright luminaries. As we continue to watch them we find that the immense majority of them shine with a twinkling light, and retain the same relative position to each other, whilst the remainder, very few in number, shed a steady light, and change their places continually, returning at given periods in the same path. We are thus led to divide the heavenly bodies within the sphere of our perception into two principal classes or systems—the sidereal—as we will call it here, for convenience' sake—and the planetary. The stars belonging to the former are popularly called fixed stars, although this term, in its strictest acceptation, must be held not to be