[Illustration:  Fig. 47.—­Illustrating Movements of a Superior Planet.]

The reader should draw the orbits in proportion, and, remembering the relative speed of each planet, note the movement of each in different parts of their orbits.

To account for these most simple movements, the earlier astronomers invented the most complex and impossible machinery.  They thought the earth the centre, and that the sun, moon, and stars were carried about it, as stoves around a person to warm him.  They thought these strange movements of the planets were accomplished by mounting them on subsidiary eccentric wheels in the revolving crystal sphere.  All that was [Page 115] needed to give them a right conception was a sinking of their world and themselves to an appropriate proportion, and an enlargement of their vision, to take in from an exalted stand-point a view of the simplicity of the perfect plan.

EXPERIMENTS.

Fix a rod, or tube, or telescope pointing at a star in the cast or west, and the earth’s revolution will be apparent in a moment, turning the tube away from the star.  Point it at stars about the north pole, and those on one side will be found going in an opposite direction from those on the other, and very much slower than those about the equator.  Anyone can try the pendulum experiment who has access to some lofty place from which to suspend the ball.  It was tried in Bunker Hill Monument a few years ago, and is to be tried in Paris, in the summer of 1879, with a seven-hundred-pound pendulum and a suspending wire seventy yards long.  The advance and retrograde movements of planets can be illustrated by two persons walking around a centre and noticing the place where the person appears projected on the wall beyond.

* * * * *

  PROCESSION OF STARS AND SOULS.

  “I stood upon the open casement,
     And looked upon the night,
   And saw the westward-going stars
     Pass slowly out of sight.

  “Slowly the bright procession
     Went down the gleaming arch,
   And my soul discerned the music
     Of the long triumphal march;

  “Till the great celestial army,
     Stretching far beyond the poles,
   Became the eternal symbol
     Of the mighty march of souls.

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  “Onward, forever onward,
     Red Mars led on his clan;
   And the moon, like a mailed maiden,
     Was riding in the van.

  “And some were bright in beauty,
     And some were faint and small,
   But these might be, in their great heights,
     The noblest of them all.

  “Downward, forever downward,
     Behind earth’s dusky shore,
   They passed into the unknown night—­
     They passed, and were no more.

  “No more!  Oh, say not so! 
     And downward is not just;
   For the sight is weak and the sense is dim
     That looks through heated dust.