Salusbury, Thomas, Mathematical collections and translations (Tome I), 1667
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              more than truth, when it is before hand 23. or 24. Degrees high,
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              would be the leſſening its
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              Parallax
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              about 3. minutes, the which
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              abatement is too ſmall to pull down the Star below the Moon, and
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              in ſome caſes is leſſe than the advantage given him by us in
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              ting that the exceſſe of the inferiour diſtance from the Pole above
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              the Superiour, is all
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              Parallax,
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              the which advantage is far more clear
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              and palpable than the effect of Refracton, of the greatneſſe of
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              which I ſtand in doubt, and not without reaſon. </s>
              <s>But beſides, I
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              demand of the Author, whether he thinks that thoſe Aſtronomers,
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              of whoſe obſervations he maketh uſe, had knowledge of theſe
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              fects of Refractions, and conſidered the ſame, or no; if they did
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              know and conſider them, it is reaſonable to think that the, kept
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              count of them in aſſigning the true Elevation of the Star, making
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              in thoſe degrees of Altitude diſcovered with the Inſtruments, ſuch
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              abatements as were convenient on the account of the alterations
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              made by the Refractions; inſomuch that the diſtances by them
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              livered, were in the end thoſe corrected and exact, and not the
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              parent and falſe ones. </s>
              <s>But if he think that thoſe Authors made
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              no reflection upon the ſaid Refractions, it muſt be confeſſed, that
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              they had in like manner erred in determining all thoſe things which
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              cannot be perfectly adjuſted without allowance for the
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              ons; amongſt which things one is the preciſe inveſtigation of the
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              Polar Altitudes, which are commonly taken from the two
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              an Altitudes of ſome of the fixed Stars that are conſtantly viſible,
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              which Altitudes will come to be altered by Refraction in the ſame
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              manner, juſt as thoſe of the new Star; ſo that the Polar Altitude
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              that is deduced from them, will prove to be defective, and to
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              take of the ſelf ſame want which this Author aſſigns to the
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              tudes aſcribed to the new Star, to wit, both that and theſe will
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              be with equal falſhood placed higher than really they are. </s>
              <s>But any
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              ſuch errour, as far as concerns our preſent buſineſſe, doth no
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              judce at all: For we not needing to know any more, but onely
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              the difference between the two diſtances of the new Star from the
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              Pole at ſuch time as it was inferiour and ſuperiour, it is evident that
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              ſuch diſtances would be the ſame, taking the alteration of
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              ction commonly for the Star and for the Pole, or for them when
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              commonly amended. </s>
              <s>The Authors Argument would indeed have
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              had ſome ſtrength, though very ſmall, if he had aſſured us that
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              the Altitude of the Pole had been once preciſely aſſigned, and
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              rected from the errour depending on refraction, from which
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              gain the Aſtronomers had not kept themſelves in aſſigning the
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              titudes of the new Star; but he hath not aſcertained us of that,
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              nor perhaps could he have done, nor haply, (and this is more
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              bable) was that caution wanting in the Obſervators.</s>
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              <s>SAGR. </s>
              <s>This argument is in my judgment ſufficiently </s>
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