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who have pretended to deduce it from their Observations. I believe, that I may venture to say, that in either of the two Stars last mentioned, it does not amount to 2". I am of Opinion, that if it were 1", I should have perceived it, in the great number of Observations that I made especially of ycDraconis\ which agreeing with the Hypothesis (without allowing any thing for Parallax) nearly as well when the Sun was in Conjunction with, as in Opposition to, this Star, it Seems very probable that the Parallax of it is not fo great as one single Second ; and consequently that it is above 400000 rimes farther from us than the Sun.
There appearing therefore after all, no sensible Parallax in the fixt Stars, the Anti-Copernicans have still room on that Account, to objeCt against the Motion of the Earth; and they may have (if they please) a much greater Objection against the Hypothefis, by which I have endeavoured to fblve the fore-mentioned Phenomena ; by denying the progressive Motion of Light, as well as that of the Earth.
But as I do not apprehend, that either of these Postulates will be denied me by the Generality of the Astronomers and Philofophers of the present Age; fb I shall not doubt of obtaining their ASIent to the ConSequences, which I have deduced from them ; if they are fuch as have the Approbation of fo great a Judge of them as yourself. I am,
Sir, lour rnojl Obedient
( 661 )
AS to the Observations of Dr. Hook, I must own to
you, that before Mr. Molyneux’s Instrument was erected, I had no small Opinion of their Correctness; the Length of his Telefcope and the Care he pretends to have taken in making them exact, having been strong Inducements with me to think them fo. And since I have been convinced both from Mr. Molyneux's Observations and my own, that the Doctor’s are really very far from being either exact or agreeable to the Phenomena ; I am greatly at a Lofs how to account for it, I cannot well conceive that an Instrument of the Length of 36 Feet, constructed in the Manner he describes his, could have been liable to an Error oS near 30" (which was doubtleSs the CaSe) if rectified with fo much Care as he reprefents.
The Observations of Mr. Flamjieed of the different Distances of the Pole Star from the Pole at different Times of the Year, which were through Mistake looked upon by fome as a Proof of the annual Parallax of it, seem to have been made with much greater Care than thofe of Dr. Hook. For though they do not all exactly correspond with each other, yet from the whole Mr. Flamjieed concluded that the Star was 35" 40" or 45" nearer the Pole in December than in May or July: and according to my Hypothefis it ought to appear 40" nearer in 'December than in June. The Agreement therefore of the Observations with the Hypothesis is greater than could reasonably be expected, considering the Radius of the Instrument, and the Manner in which it was constructed.