1illuminated parts of the Terreſtrial ſuperficies appear beheld from
the Moon, depends not on this alone, but on the divers aſpects
which the Moon is ſtill changing with the Sun; ſo that, if for
ſtance, the Moon punctually followed the motion of the Sun, and
ſtood, for example, always in a direct line between it and the
Earth, in that aſpect which we call Conjunction, it looking always
to the ſame Hemiſphere of the Earth which the Sun looks unto,
ſhe would behold the ſame all light: as on the contrary, if it ſhould
always ſtay in Oppoſition to the Sun, it would never behold the
Earth, of which the dark part would be continually turn'd towards
the Moon, and therefore inviſible. But when the Moon is in
Quadrature of the Sun, that half of the Terreſtrial Hemiſphere
poſed to the ſight of the Moon which is towards the Sun, is
nous; and the other towards the contrary is obſcure: and
fore the illuminated part of the Earth would repreſent it ſelf to the
Moon in a ſemi-circular figure.
the Moon, depends not on this alone, but on the divers aſpects
which the Moon is ſtill changing with the Sun; ſo that, if for
ſtance, the Moon punctually followed the motion of the Sun, and
ſtood, for example, always in a direct line between it and the
Earth, in that aſpect which we call Conjunction, it looking always
to the ſame Hemiſphere of the Earth which the Sun looks unto,
ſhe would behold the ſame all light: as on the contrary, if it ſhould
always ſtay in Oppoſition to the Sun, it would never behold the
Earth, of which the dark part would be continually turn'd towards
the Moon, and therefore inviſible. But when the Moon is in
Quadrature of the Sun, that half of the Terreſtrial Hemiſphere
poſed to the ſight of the Moon which is towards the Sun, is
nous; and the other towards the contrary is obſcure: and
fore the illuminated part of the Earth would repreſent it ſelf to the
Moon in a ſemi-circular figure.
SAGR. I clearly perceive all this, and underſtand very well,
that the Moon departing from its Oppoſition to the Sun, where it
ſaw no part of the illumination of the Terreſtrial ſuperficies, and
approaching day by day nearer the Sun, ſhe begins by little and
little to diſcover ſome part of the face of the illuminated Earth;
and that which appeareth of it ſhall reſemble a thin ſickle, in regard
the figure of the Earth is round: and the Moon thus acquiring by
its motion day by day greater proximity to the Sun, ſucceſſively
diſcovers more and more of the Terreſtrial Hemiſphere enlightned,
ſo that at the Quadrature there is juſt half of it viſible, inſomuch
that we may ſee the other part of her: continuing next to proceed
towards the Conjunction, it ſucceſſively diſcovers more and more
of its ſurface to be illuminated, and in fine, at the time of
ction ſeeth the whole Hemiſphere enlightned. And in ſhort, I
very well conceive, that what befalls the Inhabitants of the Earth,
in beholding the changes of the Moon, would happen to him that
from the Moon ſhould obſerve the Earth; but in a contrary order,
namely, that when the Moon is to us at her full, and in Oppoſition
to the Sun, then the Earth would be in Conjunction with the Sun,
and wholly obſcure and inviſible; on the contrary, that poſition
which is to us a Conjunction of the Moon with the Sun, and for
that cauſe a Moon ſilent and unſeen, would be there an Oppoſition
of the Earth to the Sun, and, to ſo ſpeak, Full Earth, to wit, all
enlightned. And laſtly, look what part of the Lunar ſurface
pears to us from time to time illuminated, ſo much of the Earth
in the ſame time ſhall you behold from the Moon to be obſcured:
and look how much of the Moon is to us deprived of light, ſo much
of the Earth is to the Moon illuminated. In one thing yet theſe
mutual operations in my judgment ſeem to differ, and it is, that it
that the Moon departing from its Oppoſition to the Sun, where it
ſaw no part of the illumination of the Terreſtrial ſuperficies, and
approaching day by day nearer the Sun, ſhe begins by little and
little to diſcover ſome part of the face of the illuminated Earth;
and that which appeareth of it ſhall reſemble a thin ſickle, in regard
the figure of the Earth is round: and the Moon thus acquiring by
its motion day by day greater proximity to the Sun, ſucceſſively
diſcovers more and more of the Terreſtrial Hemiſphere enlightned,
ſo that at the Quadrature there is juſt half of it viſible, inſomuch
that we may ſee the other part of her: continuing next to proceed
towards the Conjunction, it ſucceſſively diſcovers more and more
of its ſurface to be illuminated, and in fine, at the time of
ction ſeeth the whole Hemiſphere enlightned. And in ſhort, I
very well conceive, that what befalls the Inhabitants of the Earth,
in beholding the changes of the Moon, would happen to him that
from the Moon ſhould obſerve the Earth; but in a contrary order,
namely, that when the Moon is to us at her full, and in Oppoſition
to the Sun, then the Earth would be in Conjunction with the Sun,
and wholly obſcure and inviſible; on the contrary, that poſition
which is to us a Conjunction of the Moon with the Sun, and for
that cauſe a Moon ſilent and unſeen, would be there an Oppoſition
of the Earth to the Sun, and, to ſo ſpeak, Full Earth, to wit, all
enlightned. And laſtly, look what part of the Lunar ſurface
pears to us from time to time illuminated, ſo much of the Earth
in the ſame time ſhall you behold from the Moon to be obſcured:
and look how much of the Moon is to us deprived of light, ſo much
of the Earth is to the Moon illuminated. In one thing yet theſe
mutual operations in my judgment ſeem to differ, and it is, that it