400 Prof. Leslie on the Light of the Moon and the Planets. 
sed with a faint mistiness, vulgarly, but graphically, termed 
66 The old moon in the new moon’s arms.” This appearance is 
commonly attributed by astronomers to reflected light from our 
earth. Were the whole of the incident solar beams sent back, 
the illuminating power would no doubt be thirteen times great- 
er than that of the moon herself, and would hence amount to the 
16,000th part of the direct influence of the sun. But the waters, 
which cover three-fourths of the surface of our globe, could 
reflect only the 55th part of the incident light ; and the reflexion 
from the land would be far inferior. We may, therefore, in- 
fer, that the moon receives from earth less than the millionth 
part of the light sent to her from the sun. Such a faint illumi- 
nation is hence quite insufficient to explain the cinereous aspect 
of the old moon, which seems to be the mere expiring glow of 
phosphorescence after it has long spent its force. This explica- 
tion is confirmed by the existence of the fine silvery thread 
which appears to half inclose the ashy circle. If this extreme 
margin had been illumined by the earth, it would, from its ob- 
liquity, have appeared even fainter than the rest of the sur- 
face. But, being the last portion lighted up by the sun, it 
continues to glow for a short space after it has retired from his 
rays, and, presenting to the eye a very contracted front, or be- 
mg foreshortened, it appears the more vivid. 
Were we to indulge imagination, we might suppose that the 
Moon has been a comet, which, chancing to come near the Earth, 
and to cross its path at right angles, was constrained to obey its 
predominant attraction, and henceforth to circulate about our 
planet. Its approximation, by raising stupendous tides, would 
have occasioned one of those overwhelming convulsions which 
this globe appears to have repeatedly suffered. But the new 
satellite would soon lose its fiery constitution, and conglomerate 
into a solid mass. In its subsequent progress, it will gradually 
assume a more earthly appearance. But when it shall have at- 
tained, in the succession of distant ages, the ultimate term of 
amelioration, the Moon will no longer cheer our nights by her 
soft and silvery beams ; she will become dim and w T ane, and seem 
almost blotted from the blue vault of heaven. To cur most 
distant posterity this prospect is indeed gloomy ; but other 
changes will arise to renovate and embellish the great spectacle 
of the Universe. 
