1facility apprehended in the Prolomaick Syſteme.
SALV. I neither ought, nor can deny any thing that Sagredus
ſhall requeſt: And the delay by me deſired was to no other end,
ſave only that I might have time once again to methodize thoſe
prefatory points, in my fancy, that ſerve for a large and plain
claration of the manner how the forenamed accidents follow, as
well in the Copernican poſition, as in the Ptolomaick: nay, with
much greater facility and ſimplicity in that than in this. Whence
one may manifeſtly conceive that Hypotheſis to be as eaſie to be
effected by nature, as difficult to be apprehended by the
ſtanding: yet nevertheleſſe, I hope by making uſe of another
kind of explanation, than that uſed by Copernicus, to render
wiſe the apprehending of it ſomewhat leſſe obſcure. Which
that I may do, I will propoſe certain ſuppoſitions of themſelves
known and manifeſt, and they ſhall be theſe that follow.
ſhall requeſt: And the delay by me deſired was to no other end,
ſave only that I might have time once again to methodize thoſe
prefatory points, in my fancy, that ſerve for a large and plain
claration of the manner how the forenamed accidents follow, as
well in the Copernican poſition, as in the Ptolomaick: nay, with
much greater facility and ſimplicity in that than in this. Whence
one may manifeſtly conceive that Hypotheſis to be as eaſie to be
effected by nature, as difficult to be apprehended by the
ſtanding: yet nevertheleſſe, I hope by making uſe of another
kind of explanation, than that uſed by Copernicus, to render
wiſe the apprehending of it ſomewhat leſſe obſcure. Which
that I may do, I will propoſe certain ſuppoſitions of themſelves
known and manifeſt, and they ſhall be theſe that follow.
The
can Syſteme
cult to be
ſtood, but eaſie to
be effected.
can Syſteme
cult to be
ſtood, but eaſie to
be effected.
Neceſſary
poſitions for the
better conceiving
of the conſequences
of the Earths
tion.
poſitions for the
better conceiving
of the conſequences
of the Earths
tion.
Firſt, I ſuppoſe that the Earth is a ſpherical body, turning
round upon its own Axis and Poles, and that each point aſſigned
in its ſuperficies, deſcribeth the circumference of a circle,
er or leſſer, according as the point aſſigned ſhall be neerer or
farther from the Poles: And that of theſe circles the greateſt is
that which is deſcribed by a point equidiſtant from the ſaid Poles;
and all theſe circles are parallel to each other; and Parallels we
will call them.
round upon its own Axis and Poles, and that each point aſſigned
in its ſuperficies, deſcribeth the circumference of a circle,
er or leſſer, according as the point aſſigned ſhall be neerer or
farther from the Poles: And that of theſe circles the greateſt is
that which is deſcribed by a point equidiſtant from the ſaid Poles;
and all theſe circles are parallel to each other; and Parallels we
will call them.
Secondly, The Earth being of a Spherical Figure, and of an
pacous ſubſtance, it is continually illuminated by the Sun,
ding to the half of its ſurface, the other half remaining obſcure,
and the boundary that diſtinguiſheth the illuminated part from
the dark being a grand circle, we will call that circle the
nator of the light.
pacous ſubſtance, it is continually illuminated by the Sun,
ding to the half of its ſurface, the other half remaining obſcure,
and the boundary that diſtinguiſheth the illuminated part from
the dark being a grand circle, we will call that circle the
nator of the light.
Thirdly, If the Circle that is terminator of the light ſhould
paſſe by the Poles of the Earth, it would cut (being a grand
and principal circle) all the parallels into equal parts; but not
paſſing by the Poles, it would cut them all in parts unequal,
cept only the circle in the middle, which, as being a grand circle
will be cut into equal parts.
paſſe by the Poles of the Earth, it would cut (being a grand
and principal circle) all the parallels into equal parts; but not
paſſing by the Poles, it would cut them all in parts unequal,
cept only the circle in the middle, which, as being a grand circle
will be cut into equal parts.
Fourthly, The Earth turning round upon its own Poles, the
quantities of dayes and nights are termined by the arches of the
Parallels, interſected by the circle, that is, the terminator of the
light, and the arch that is ſcituate in the illuminated Hemiſphere
preſcribeth the length of the day, and the remainer is the
tity of the night.
quantities of dayes and nights are termined by the arches of the
Parallels, interſected by the circle, that is, the terminator of the
light, and the arch that is ſcituate in the illuminated Hemiſphere
preſcribeth the length of the day, and the remainer is the
tity of the night.
Theſe things being preſuppoſed, for the more clear
ſtanding of that which remaines to be ſaid, we will lay it down
in a Figure. And firſt, we will draw the circumference of a
circle, that ſhall repreſent unto us that of the grand Orb
ſtanding of that which remaines to be ſaid, we will lay it down
in a Figure. And firſt, we will draw the circumference of a
circle, that ſhall repreſent unto us that of the grand Orb
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