illuminated parts of the Terre&longs;trial &longs;uperficies appear beheld from <lb/>
the Moon, depends not on this alone, but on the divers a&longs;pects <lb/>
which the Moon is &longs;till changing with the Sun; &longs;o that, if for in <lb/>
&longs;tance, the Moon punctually followed the motion of the Sun, and <lb/>
&longs;tood, for example, always in a direct line between it and the <lb/>
Earth, in that a&longs;pect which we call Conjunction, it looking always <lb/>
to the &longs;ame Hemi&longs;phere of the Earth which the Sun looks unto, <lb/>
&longs;he would behold the &longs;ame all light: as on the contrary, if it &longs;hould <lb/>
always &longs;tay in Oppo&longs;ition to the Sun, it would never behold the <lb/>
Earth, of which the dark part would be continually turn'd towards <lb/>
the Moon, and therefore invi&longs;ible. </s><s>But when the Moon is in <lb/>
Quadrature of the Sun, that half of the Terre&longs;trial Hemi&longs;phere ex <lb/>
po&longs;ed to the &longs;ight of the Moon which is towards the Sun, is lumi <lb/>
nous; and the other towards the contrary is ob&longs;cure: and there <lb/>
fore the illuminated part of the Earth would repre&longs;ent it &longs;elf to the <lb/>
Moon in a &longs;emi-circular figure.</s></p>

<p type="main"><s>SAGR. </s><s>I clearly perceive all this, and under&longs;tand very well, <lb/>
that the Moon departing from its Oppo&longs;ition to the Sun, where it <lb/>
&longs;aw no part of the illumination of the Terre&longs;trial &longs;uperficies, and <lb/>
approaching day by day nearer the Sun, &longs;he begins by little and <lb/>
little to di&longs;cover &longs;ome part of the face of the illuminated Earth; <lb/>
and that which appeareth of it &longs;hall re&longs;emble a thin &longs;ickle, in regard <lb/>
the figure of the Earth is round: and the Moon thus acquiring by <lb/>
its motion day by day greater proximity to the Sun, &longs;ucce&longs;&longs;ively <lb/>
di&longs;covers more and more of the Terre&longs;trial Hemi&longs;phere enlightned, <lb/>
&longs;o that at the Quadrature there is ju&longs;t half of it vi&longs;ible, in&longs;omuch <lb/>
that we may &longs;ee the other part of her: continuing next to proceed <lb/>
towards the Conjunction, it &longs;ucce&longs;&longs;ively di&longs;covers more and more <lb/>
of its &longs;urface to be illuminated, and in fine, at the time of Conjun <lb/>
ction &longs;eeth the whole Hemi&longs;phere enlightned. </s><s>And in &longs;hort, I <lb/>
very well conceive, that what befalls the Inhabitants of the Earth, <lb/>
in beholding the changes of the Moon, would happen to him that <lb/>
from the Moon &longs;hould ob&longs;erve the Earth; but in a contrary order, <lb/>
namely, that when the Moon is to us at her full, and in Oppo&longs;ition <lb/>
to the Sun, then the Earth would be in Conjunction with the Sun, <lb/>
and wholly ob&longs;cure and invi&longs;ible; on the contrary, that po&longs;ition <lb/>
which is to us a Conjunction of the Moon with the Sun, and for <lb/>
that cau&longs;e a <emph type="italics"/>M<emph.end type="italics"/>oon &longs;ilent and un&longs;een, would be there an Oppo&longs;ition <lb/>
of the Earth to the Sun, and, to &longs;o &longs;peak, <emph type="italics"/>Full Earth,<emph.end type="italics"/> to wit, all <lb/>
enlightned. </s><s>And la&longs;tly, look what part of the Lunar &longs;urface ap <lb/>
pears to us from time to time illuminated, &longs;o much of the Earth <lb/>
in the &longs;ame time &longs;hall you behold from the Moon to be ob&longs;cured: <lb/>
and look how much of the Moon is to us deprived of light, &longs;o much <lb/>
of the Earth is to the Moon illuminated. </s><s>In one thing yet the&longs;e <lb/>
mutual operations in my judgment &longs;eem to differ, and it is, that it