COMMENTATIO ASTRONOMICA. 171 



« renl lustre; for that is not sensibly different in such slars es seem near togelher, 

 « tliough ihey appear of very dififerent magnitudes. And whatever their situations are 

 « ( if I proceed according to Ihe foregoing hypothesis ) I find the same velocity of light 

 from my observalions of small slars of the fifth or sixth, as from those of ihe second 

 <i and Ihird magnitude, which in all probability are placed at very different distances 

 « from US. " 



Hoc probat exemplis. Jam allatis observationibus aliarum fixarum , maximam devia- 

 tionem invenit 40 ',5 , quam non credit unico secundo a vera differre. Dein via contra- 

 ria ex hoc maximo secundum legem repertam quaerit variationes, quas subire debuit 

 declinatio Draconis <y , et cum his comparat variationes per anni spatium revera obser- 

 valas. Differentiae limiles errorum non excedunt. Sed praeter Draconis y , insuper ex- 

 hibet Ursae majoris vi, in qua non minor est hypolheseos et observationis conspirantia. 

 Simul autem haec Stella probat variationem praecessionis. 



« But I may hereafler, perhaps, be better able to delermiae tbis point, from my ob- 

 « servations of those stars that lie near the equinoclial colure , at about the same di- 

 « stance from the north pole of the equalor , and nearly opposite in right ascension." 



« I think it needless to give you the comparison belween the hypothesis and the oh- 

 (I servations of any more stars; since the agreement in the foregoing is a kind of demon- 

 « stration (whether it be allowed that I have discovered the real cause of the jiliaeno- 

 « mena or not;) that the hypothesis gives at least the true law of the Variation of de- 

 « clination in different stars , with respect to their different situations and aspects with 

 « the sun. And if this is the case , it must be granled , that the parallas of Ihe fixt 

 « stars is much smaller, than halb been hitherto supposed by those, who have pretended 

 « to deduce it from their observalions. I beheve , that I may venture to say , Ihat in 

 « either of the two stars last mentioned , in does not amount to 2". I am of opinions, 

 « that if it were 1", I should have perceived it , in the great number of observalions 

 « that I made esspecially of y Draconis; which agreeing with the hypothesis (without 

 « allowing any thing for parallai) nearly as well when the sun was in conjunctioa 

 « with, as in Opposition to , Ihis slar, it seems very probable that the parallas of it 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 afler all , iio sensible parallax 

 « in the fixt stars, the Anti- Copernicans have still room on that account, to object 

 « against the motion of the earth; and Ihey may have (if Ihey please) a much grealer 

 « objection against the hypothesis , by which I have endeavoured to solve the fore- 

 <i mentioned phaenomena; by denying the progressive motion of light , as well as that 

 <r of the earlh. " 

 <( But as I do not apprehend, that either of these postulates will be denied me by the 



y 2 « ge. 



