its physical condition. For a very long time our satellite was
confidently, and almost universally, regarded as an airless, waterless,
lifeless desert, a completely "dead world," a bare, desiccated skull of
rock, circling about the living earth.

But within a few years there has been a reaction from this extreme view
of the lifelessness of the moon. Observers tell us of clouds suddenly
appearing and then melting to invisibility over volcanic craters; of
evidences of an atmosphere, rare as compared with ours, yet manifest in
its effects; of variations of color witnessed in certain places as the
sunlight drifts over them at changing angles of incidence; of what seem
to be immense fields of vegetation covering level ground, and of
appearances indicating the existence of clouds of ice crystals and
deposits of snow among the mountainous lunar landscapes. Thus, in a
manner, the moon is rehabilitated, and we are invited to regard its
silvery beams not as the reflections of the surface of a desert, but as
sent back to our eyes from the face of a world that yet has some slight
remnants of life to brighten it.

The suggestion that there is an atmosphere lying close upon the shell of
the lunar globe, filling the deep cavities that pit its face and
penetrating to an unknown depth in its interior, recalls a speculation
of the ingenious and entertaining Fontenelle, in the seventeenth
century--recently revived and enlarged upon by the author of one of our
modern romances of adventure in the moon--to the effect that the lunar
inhabitants dwell beneath the surface of their globe instead of on the
top of it.

Now, because of this widespread and continually increasing interest in
the subject of other worlds, and on account of the many curious