1twice as great as that from the Sun to us) in the ſtar of Saturn is
almoſt totally imperceptible, and in Jupiter not very
ble, what ſhall we think of the fixed ſtars, which I believe you
will not ſcruple to place twice as far off as Saturn? In Mars,
which for that it is nearer to us -------
almoſt totally imperceptible, and in Jupiter not very
ble, what ſhall we think of the fixed ſtars, which I believe you
will not ſcruple to place twice as far off as Saturn? In Mars,
which for that it is nearer to us -------
In objects far
remote, and
nous, a ſmall
proach or receſſion
is imperceptible.
remote, and
nous, a ſmall
proach or receſſion
is imperceptible.
SIMP. Pray Sir, put your ſelf to no farther trouble in this
particular, for I already conceive that what hath been ſpoken
touching the unaltered apparent magnitude of the fixed ſtars may
very well come to paſſe, but what ſhall we ſay of the other
ficulty that proceeds from not perceiving any variation in the
mutation of aſpect?
particular, for I already conceive that what hath been ſpoken
touching the unaltered apparent magnitude of the fixed ſtars may
very well come to paſſe, but what ſhall we ſay of the other
ficulty that proceeds from not perceiving any variation in the
mutation of aſpect?
SALV. We will ſay that which peradventure may ſatisfie
you alſo in this particular. And to make ſhort, would you not
be ſatisfied if there ſhould be diſcovered in the ſtars face
tions that you think ought to be diſcovered, in caſe the annual
motion belonged to the Earth?
you alſo in this particular. And to make ſhort, would you not
be ſatisfied if there ſhould be diſcovered in the ſtars face
tions that you think ought to be diſcovered, in caſe the annual
motion belonged to the Earth?
SIMP. I ſhould ſo doubtleſſe, as to what concerns this
ticular.
ticular.
SALV. I could wiſh you would ſay that in caſe ſuch a
rence were diſcovered, nothing more would remain behind, that
might render the mobility of the Earth queſtionable. But
though yet that ſhould not ſenſibly appear, yet is not its
bility removed, nor its immobility neceſſarily proved, it being
poſſible, (as Copernicus affirmeth) that the immenſe diſtance of
the Starry Sphere rendereth ſuch very ſmall Phænomena
vable; the which as already hath been ſaid, may poſſibly not
have been hitherto ſo much as ſought for, or if ſought for, yet
not ſought for in ſuch a way as they ought, to wit, with that
exactneſſe which to ſo minute a punctuality would be neceſſary;
which exactneſſe is very difficult to obtain, as well by reaſon of the
deficiency of Aſttonomical Inſtruments, ſubject to many
tions, as alſo through the fault of thoſe that manage them with leſs
diligence then is requiſite. A neceſſary argument how little
dit is to be given to thoſe obſervations may be deduced from the
differences which we find amongſt Aſtronomers in aſſigning the
places, I will not ſay, of the new Stars or Comets, but of the fixed
ſtars themſelves, even to the altitudes of the very Poles, in
which, moſt an end, they are found to differ from one another
many minutes. And to ſpeak the truth, who can in a Quadrant,
or Sextant, that at moſt ſhall have its ſide ^{*} 3. or 4. yards long,
aſcertain himſelf in the incidence of the perpendicular, or in the
direction of the ſights, not to erre two or three minutes, which
in its circumference ſhall not amount to the breadth of a grain of
^{*}Mylet? Beſides that, it is almoſt impoſſible, that the Inſtrument
ſhould be made, and kept with abſolute exactneſſe. Ptolomey
rence were diſcovered, nothing more would remain behind, that
might render the mobility of the Earth queſtionable. But
though yet that ſhould not ſenſibly appear, yet is not its
bility removed, nor its immobility neceſſarily proved, it being
poſſible, (as Copernicus affirmeth) that the immenſe diſtance of
the Starry Sphere rendereth ſuch very ſmall Phænomena
vable; the which as already hath been ſaid, may poſſibly not
have been hitherto ſo much as ſought for, or if ſought for, yet
not ſought for in ſuch a way as they ought, to wit, with that
exactneſſe which to ſo minute a punctuality would be neceſſary;
which exactneſſe is very difficult to obtain, as well by reaſon of the
deficiency of Aſttonomical Inſtruments, ſubject to many
tions, as alſo through the fault of thoſe that manage them with leſs
diligence then is requiſite. A neceſſary argument how little
dit is to be given to thoſe obſervations may be deduced from the
differences which we find amongſt Aſtronomers in aſſigning the
places, I will not ſay, of the new Stars or Comets, but of the fixed
ſtars themſelves, even to the altitudes of the very Poles, in
which, moſt an end, they are found to differ from one another
many minutes. And to ſpeak the truth, who can in a Quadrant,
or Sextant, that at moſt ſhall have its ſide ^{*} 3. or 4. yards long,
aſcertain himſelf in the incidence of the perpendicular, or in the
direction of the ſights, not to erre two or three minutes, which
in its circumference ſhall not amount to the breadth of a grain of
^{*}Mylet? Beſides that, it is almoſt impoſſible, that the Inſtrument
ſhould be made, and kept with abſolute exactneſſe. Ptolomey