62 THE BORDERLAND OF SCIENCE. 



darkness where stars were blotted from view by the 

 earth's globe. We could see this dark disc gradually 

 contracting, like the pupil of an eye, as we travelled 

 onwards, and we could in some sort estimate our posi- 

 tion by noting the dimensions of this gigantic eye, 

 whose iris was the star-bespangled sky, while its pupil 

 was the great globe itself which men inhabit. 



Presently, as we travelled onwards, the moon appeared 

 on the left of the earth. So soon as her full disc was 

 uncovered we saw her as a fine sickle of light. But to 

 our astonishment the rest of her disc was particoloured. 

 The part farthest on the left was perfectly black, its 

 outer outline only distinguishable because projected on 

 the starlit sky. This part formed a black sickle almost 

 exactly opposite to the sickle of true moonlight. But 

 between the white and black sickles lay a half-lit space 

 of a bluish-green colour. This colour was well marked, 

 and we were at some loss to account for it, until X. 

 pointed out that this part of the moon's surface was 

 illuminated by earthshine chiefly coming from the 

 Pacific Ocean, whence doubtless proceeded the beauti- 

 ful tint which was spread over the middle of the lunar 

 disc. 



Passing farther away, we saw that the left side of 

 the earth's disc began to be illumined by a faint light 

 received from the moon. Elsewhere, however, the 

 disc of the earth continued perfectly dark, until we 

 began to approach the orbit of the moon, when we 

 could perceive that all round the earth's disc a deep 

 red light was making its appearance. Before long we 



