1more than truth, when it is before hand 23. or 24. Degrees high,
would be the leſſening its Parallax about 3. minutes, the which
abatement is too ſmall to pull down the Star below the Moon, and
in ſome caſes is leſſe than the advantage given him by us in
ting that the exceſſe of the inferiour diſtance from the Pole above
the Superiour, is all Parallax, the which advantage is far more clear
and palpable than the effect of Refracton, of the greatneſſe of
which I ſtand in doubt, and not without reaſon. But beſides, I
demand of the Author, whether he thinks that thoſe Aſtronomers,
of whoſe obſervations he maketh uſe, had knowledge of theſe
fects of Refractions, and conſidered the ſame, or no; if they did
know and conſider them, it is reaſonable to think that the, kept
count of them in aſſigning the true Elevation of the Star, making
in thoſe degrees of Altitude diſcovered with the Inſtruments, ſuch
abatements as were convenient on the account of the alterations
made by the Refractions; inſomuch that the diſtances by them
livered, were in the end thoſe corrected and exact, and not the
parent and falſe ones. But if he think that thoſe Authors made
no reflection upon the ſaid Refractions, it muſt be confeſſed, that
they had in like manner erred in determining all thoſe things which
cannot be perfectly adjuſted without allowance for the
ons; amongſt which things one is the preciſe inveſtigation of the
Polar Altitudes, which are commonly taken from the two
an Altitudes of ſome of the fixed Stars that are conſtantly viſible,
which Altitudes will come to be altered by Refraction in the ſame
manner, juſt as thoſe of the new Star; ſo that the Polar Altitude
that is deduced from them, will prove to be defective, and to
take of the ſelf ſame want which this Author aſſigns to the
tudes aſcribed to the new Star, to wit, both that and theſe will
be with equal falſhood placed higher than really they are. But any
ſuch errour, as far as concerns our preſent buſineſſe, doth no
judce at all: For we not needing to know any more, but onely
the difference between the two diſtances of the new Star from the
Pole at ſuch time as it was inferiour and ſuperiour, it is evident that
ſuch diſtances would be the ſame, taking the alteration of
ction commonly for the Star and for the Pole, or for them when
commonly amended. The Authors Argument would indeed have
had ſome ſtrength, though very ſmall, if he had aſſured us that
the Altitude of the Pole had been once preciſely aſſigned, and
rected from the errour depending on refraction, from which
gain the Aſtronomers had not kept themſelves in aſſigning the
titudes of the new Star; but he hath not aſcertained us of that,
nor perhaps could he have done, nor haply, (and this is more
bable) was that caution wanting in the Obſervators.
would be the leſſening its Parallax about 3. minutes, the which
abatement is too ſmall to pull down the Star below the Moon, and
in ſome caſes is leſſe than the advantage given him by us in
ting that the exceſſe of the inferiour diſtance from the Pole above
the Superiour, is all Parallax, the which advantage is far more clear
and palpable than the effect of Refracton, of the greatneſſe of
which I ſtand in doubt, and not without reaſon. But beſides, I
demand of the Author, whether he thinks that thoſe Aſtronomers,
of whoſe obſervations he maketh uſe, had knowledge of theſe
fects of Refractions, and conſidered the ſame, or no; if they did
know and conſider them, it is reaſonable to think that the, kept
count of them in aſſigning the true Elevation of the Star, making
in thoſe degrees of Altitude diſcovered with the Inſtruments, ſuch
abatements as were convenient on the account of the alterations
made by the Refractions; inſomuch that the diſtances by them
livered, were in the end thoſe corrected and exact, and not the
parent and falſe ones. But if he think that thoſe Authors made
no reflection upon the ſaid Refractions, it muſt be confeſſed, that
they had in like manner erred in determining all thoſe things which
cannot be perfectly adjuſted without allowance for the
ons; amongſt which things one is the preciſe inveſtigation of the
Polar Altitudes, which are commonly taken from the two
an Altitudes of ſome of the fixed Stars that are conſtantly viſible,
which Altitudes will come to be altered by Refraction in the ſame
manner, juſt as thoſe of the new Star; ſo that the Polar Altitude
that is deduced from them, will prove to be defective, and to
take of the ſelf ſame want which this Author aſſigns to the
tudes aſcribed to the new Star, to wit, both that and theſe will
be with equal falſhood placed higher than really they are. But any
ſuch errour, as far as concerns our preſent buſineſſe, doth no
judce at all: For we not needing to know any more, but onely
the difference between the two diſtances of the new Star from the
Pole at ſuch time as it was inferiour and ſuperiour, it is evident that
ſuch diſtances would be the ſame, taking the alteration of
ction commonly for the Star and for the Pole, or for them when
commonly amended. The Authors Argument would indeed have
had ſome ſtrength, though very ſmall, if he had aſſured us that
the Altitude of the Pole had been once preciſely aſſigned, and
rected from the errour depending on refraction, from which
gain the Aſtronomers had not kept themſelves in aſſigning the
titudes of the new Star; but he hath not aſcertained us of that,
nor perhaps could he have done, nor haply, (and this is more
bable) was that caution wanting in the Obſervators.
SAGR. This argument is in my judgment ſufficiently
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