320 I'HILUSOPHICAL TBANSACT10N8. [aNNO 1728. 



made of it in a year, there is no difference of so much as '2', except in one, 

 which is marked as doubtful on account of the undulation of the air, 8cc. And 

 this does not differ 3" from the hypothesis. 



The agreement between the hypothesis and the observi'tions of this star, is 

 the more to be regarded, since it proves that the alteration of declination, on 

 account of the precession of the equinox, is as before supj)osed, regular through 

 all parts of the year; so far at least, as not to occasion a difference great enough 

 to be discovered with this instrument. It likewise proves the other part of the 

 former supposition, viz. that the annual alteration of declination in stars near 

 the equinoctial colure, is at this time greater than a precession of 50'' would 

 occasion: for this star was iO" more southerly in September 1728, than in 

 September 1727, that is, about 2" more than it would have been, if the pre- 

 cession was but 50". 



Mr. B. thinks it needless to give the comparison between the hypothesis and 

 the observations of any more stars ; since the agreement in the foregoing is a 

 kind of demonstration, that the hypothesis gives at least the true law of the 

 variation of declination in different stars, with respect to their different situa- 

 tions and aspects with the sun. And if this is the case, it must be granted, 

 that the parallax of the fixed stars is much smaller than has been hitherto sup- 

 posed by those, who have pretended to deduce it from their observations. Mr. 

 B. thinks he may venture to say, that in either of the two stars last mentioned, 

 it does not amount to 2''. He thinks that if it were 1 ', he should have per- 

 ceived it in the great number of observations he made, especially of y Draconis; 

 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 its parallax is not so great as one single second; 

 and consequently that it is above 400000 times farther from us than the sun. 



There appearing therefore after all, no sensible parallax in the fixed 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 hypothesis, by which Mr. B. has endeavoured to solve the foremen- 

 tioned phaenomena ; by denying the progressive motion of light, as well as that 

 of the earth. 



Postscript. — As to the observations of Dr. Hook, Mr. B. owns, that before 

 Mr. Molyneux's instrument was erected, he had no small opinion of their 

 correctness ; the length of his telescope, and the care he pretends to have taken 

 in making them exact, having been strong inducements with him to think them 

 so. And since he has been convinced, both from Mr. Molyneux's obsL-rvations, 

 and his own, that the Doctor's are really very far from being either exact or 



