330 PHILOSOPHICAL TRANSACTIONS. [aNNO 1/18. 



found to be above half a degree more southerly at this time than the ancients 

 reckoned them. When, on the contrary, at the same time the bright shoulder 

 of Orion has in Ptolomy almost a degree more southerly latitude than at pre- 

 sent. What shall we say then ? It is scarcely credible that the ancients could 

 be deceived in so plain a matter, three observers confirming each other. Again 

 these stars, being the most conspicuous in Heaven, are in all probability the 

 nearest to the earth ; and if they have any particular motion of their own, it is 

 most likely to be perceived in them, which in so long a time as 1800 years may 

 $how itself by the alteration of their places, though it be utterly imperceptible 

 in the space of a single century of years. Yet as to Sirius, it may be observed 

 that Tycho Brahe makes him 2' more northerly than we now find him ; where- 

 as he ought to be above as much more southerly from his ecliptic, (the obliquity 

 of which he makes 1^ greater than we reckon it at present) differing in the 

 whole A\\ One half of this difference may perhaps be excused, if refraction 

 were not allowed in this case by Tycho ; yet 2' in such a star as Sirius, is rather 

 too much for him to be mistaken. 



But a further and more evident proof of this change, is drawn from the ob- 

 servation of the application of the moon to Palilicium Anno Christi 509, 

 March 1 1 th, when in the beginning of the night the moon was seen to follow 

 that star very near, and seemed to have eclipsed it, Wi^olkki ycx,^ o xtnn^ tZ ttx^k 

 xnv ^KTxoTOjUi'ai' j".«f £» Ttif xvornq 'm^KpiDua,!; t5 Tn^uria-fj^ivs [xi^sq. i. e. Stella apposita erat 

 parti per quam bisecabatur limbus lunae illuminatus, as Bulliald, to whom we 

 are beholden for this ancient observation, has translated it. Now from the 

 undoubted principles of astronomy, it was impossible for this to be true at 

 Athens, or near it, unless the latitude of Palilicium were much less than we 

 at this time find it. Vide Bullialdi Astr. Philolaica, p. 172. 



But whether it were really true, that the obliquity of the ecliptic was, in the 

 time of Hipparchus and Ptolemy, really 22' greater than now, may well be 

 questioned; since Pappus Alexandrinus, who lived but about 200~ years after 

 Ptolomy, makes it the very same that we do. Vide Pappi Collect, lib. 6, 

 prop. 35. 



jin Account of some Experiments shown before the Royal Society ; with an 

 Inquiry into the Cause of the Ascent and Suspension of Water in Capillary 

 Tubes. By James Jurin* M.D. R. S. S. N° 355, p. 739- 



Some days ago a method was proposed to me by a friend, for making a per- 



• Dr. Jurin wa« a very respectable philosopher, of the Newtonian school, who cultivated medicine 

 and mathematics with equal success. He proved a very active and useful member of the Roya] 



