y, for to the naked eye she appears much larger than all the
Pleiades together. But this is not so. She only measures 31', less than
half the distance from Atlas to Celaeno; she is hardly broader than the
distance from Alcyone to Atlas, and could pass between Merope and
Taygeta without touching either of these stars. This is a perennial and
very curious optical illusion. When the Moon passes in front of the
Pleiades, and occults them successively, it is hard to believe one's
eyes. The fact occurred, _e.g._, on July 23, 1897, during a fine
occultation observed at the author's laboratory of Juvisy (Fig. 26).

[Illustration: FIG. 26.--Occultation of the Pleiades by the Moon.]

Photography here discovers to us, not 6, 9, 12, 15, or 20 stars, but
hundreds and millions.

These are the most brilliant flowers of the celestial garden.

[Illustration: FIG. 27.--Stellar dial of the double star [gamma] of the
Virgin.]

We, alas, can but glance at them rapidly. In contemplating them we are
transported into immensities both of space and time, for the stellar
periods measured by these distant universes often overpower in their
magnitude the rapid years in which our terrestrial days are estimated.
For instance, one of the double stars we spoke of above, [gamma] of the
Virgin, sees its two components, translucent diamonds, revolve around
their common center of gravity, in one hundred and eighty years. How
many events took place in France, let us say, in a single year of this
star!--The Regency, Louis XV, Louis XVI, the Revolution, Napoleon, Louis
XVIII, Louis Philippe, the Second Republic, Napoleon III, the
Franco-German War, the Third Republic.... What revolutions here, during
a single year of this radiant pair! (Fig. 27.)

But the pageant of the Heavens is too vast, too overwhelming. We must
end our survey.

Our Milky Way, with its millions of stars, represents for us only a
portion of the Creation. The illimitable abysses of Infinitude are
peopled by other universes as vast, as imposing, as our own, which are
renewed in all directions through the depths of Space to endless
distance. Where is our little Earth? Where our Solar System? We are fain
to fold our wings, and return from the Immense and Infinite to our
floating island.

CHAPTER IV

OUR STAR THE SUN

In the incessant agitation of daily life in which we are involved by the
thousand superfluous wants of modern "civilization," one is prone to
assume that exis