1circle, either bigger or leſſer, according as it is more or leſſe
mote from the ſaid Poles, let us take the point F, equally diſtant
from them, and draw the diameter F O G, which ſhall be
dicular to the Axis E I, and ſhall be the diameter of the grand
circle deſcribed about the Poles E I. Suppoſing not that the
Earth, and we with her be in ſuch a place of the Ecliptick, that
the Hemiſphere of the Sun to us apparent is determin'd or
ed by the circle A B C D, which paſſing (as it alwayes doth) by
the Poles A C, paſſeth alſo by E I. It is manifeſt, that the grand
circle, whoſe diameter is FG, ſhall be erect to the circle A B C D,
to which the ray that from our eye falleth upon the centre O, is
perpendicular; ſo that the ſaid ray falleth upon the plane of
the circle, whoſe diameter is F G, and therefore its circumference
will appear to us a right line, and the ſelf ſame with F G,
upon if there ſhould be in the point F, a ſpot, it comming
wards to be carried about by the Solar converſion, would, upon
the ſurface of the Sun, trace out the circumference of that
cle, which ſeems to us a right line. Its courſe or paſſage will
therefore ſeem ſtraight. And ſtraight alſo will the motion of the
other ſpots appear, which in the ſaid revolution ſhall deſcribe
ſer circles, as being all parallel to the greater, and to our eye
placed at an immenſe diſtance from them. Now, if you do but
conſider, how that after the Earth ſhall in ſix moneths have run
thorow half the grand Orb, and ſhall be ſituate oppoſite to that
Hemiſphere of the Sun, which is now occult unto us, ſo as that
the boundary of the part that then ſhall be ſeen, may be the ſelf
ſame A B C D, which alſo ſhall paſſe by the Poles E I; you
ſhall underſtand that the ſame will evene in the courſes of the
ſpots, as before, to wit, that all will appear to be made by right
lines. But becauſe that that accident takes not place, ſave
ly when the terminator or boundary paſſeth by the Poles E I,
and the ſaid terminator from moment to moment, by meanes of
the Earths annual motion, continually altereth, therefore its
ſage by the fixed Poles E I, ſhall be momentary, and
ly momentary ſhall be the time, in which the motions of thoſe
ſpots ſhall appear ſtraight. From what hath been hitherto ſpoken
one may comprehend alſo how that the apparition and beginning
of the motion of the ſpots from the part F, proceeding towards
G, their paſſages or courſes are from the left hand, aſcending
wards the right; but the Earth being placed in the part
trically oppoſite the appearance of the ſpots about G, ſhall ſtill
be to the left hand of the beholder, but the paſſage ſhall be
cending towards the right hand F. Let us now deſcribe the Earth
te be ſituate one fourth part farther diſtant from its preſent ſtate,
and let us draw, as in the other figure, the terminator A B C D,
mote from the ſaid Poles, let us take the point F, equally diſtant
from them, and draw the diameter F O G, which ſhall be
dicular to the Axis E I, and ſhall be the diameter of the grand
circle deſcribed about the Poles E I. Suppoſing not that the
Earth, and we with her be in ſuch a place of the Ecliptick, that
the Hemiſphere of the Sun to us apparent is determin'd or
ed by the circle A B C D, which paſſing (as it alwayes doth) by
the Poles A C, paſſeth alſo by E I. It is manifeſt, that the grand
circle, whoſe diameter is FG, ſhall be erect to the circle A B C D,
to which the ray that from our eye falleth upon the centre O, is
perpendicular; ſo that the ſaid ray falleth upon the plane of
the circle, whoſe diameter is F G, and therefore its circumference
will appear to us a right line, and the ſelf ſame with F G,
upon if there ſhould be in the point F, a ſpot, it comming
wards to be carried about by the Solar converſion, would, upon
the ſurface of the Sun, trace out the circumference of that
cle, which ſeems to us a right line. Its courſe or paſſage will
therefore ſeem ſtraight. And ſtraight alſo will the motion of the
other ſpots appear, which in the ſaid revolution ſhall deſcribe
ſer circles, as being all parallel to the greater, and to our eye
placed at an immenſe diſtance from them. Now, if you do but
conſider, how that after the Earth ſhall in ſix moneths have run
thorow half the grand Orb, and ſhall be ſituate oppoſite to that
Hemiſphere of the Sun, which is now occult unto us, ſo as that
the boundary of the part that then ſhall be ſeen, may be the ſelf
ſame A B C D, which alſo ſhall paſſe by the Poles E I; you
ſhall underſtand that the ſame will evene in the courſes of the
ſpots, as before, to wit, that all will appear to be made by right
lines. But becauſe that that accident takes not place, ſave
ly when the terminator or boundary paſſeth by the Poles E I,
and the ſaid terminator from moment to moment, by meanes of
the Earths annual motion, continually altereth, therefore its
ſage by the fixed Poles E I, ſhall be momentary, and
ly momentary ſhall be the time, in which the motions of thoſe
ſpots ſhall appear ſtraight. From what hath been hitherto ſpoken
one may comprehend alſo how that the apparition and beginning
of the motion of the ſpots from the part F, proceeding towards
G, their paſſages or courſes are from the left hand, aſcending
wards the right; but the Earth being placed in the part
trically oppoſite the appearance of the ſpots about G, ſhall ſtill
be to the left hand of the beholder, but the paſſage ſhall be
cending towards the right hand F. Let us now deſcribe the Earth
te be ſituate one fourth part farther diſtant from its preſent ſtate,
and let us draw, as in the other figure, the terminator A B C D,
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