VOL. XII.] PHILOSOPHICAL TRANSACTIONS. 447 



thoughts of correcting them ; but presently foresaw that could never be well 

 done, without a more correct catalogue of the fixed stars, a task which was 

 already undertaken by other excellent hands. He therefore chose rather to 

 take upon himself the stating of the places of the fixed stars near the south 

 pole, and out of our horizon. And being approved and encouraged by such 

 respectable persons as Lord Brouncker, Sir Joseph Williamson, Sir Jonas Moore, 

 and others, and even by the King also, he furnished himself with such instru- 

 ments as were necessary for his purpose : which he particularly mentions and 

 describes. Of these, he says, he made the utmost and most assiduous use 

 that could be, in a place of so thick and cloudy a sky as that of St. Helena, 

 contrary to common report, proved to be; having restored about 350 fixed 

 stars, which were omitted in Tycho's catalogue. 



To his own observations the author has added an ancient catalogue outof Clavius*s 

 Commentaries in Sphaeram Jo. de Sacrobosco ; and that of Bartschius e Tabulis 

 Rudolphinis Kepleri : that being compared with these his observations, it might 

 evidently appear how very much the ancient globes almost every where difl^er 

 from the heavens. From these observations, as he proceeds, he also proposes 

 some conjectures of the corruptibility, or at least the mutability of the fixed 

 stars. Next follows a table of the right ascensions of the southern fixed stars, 

 and their distances from the pole : for the use of navigators. To which is 

 subjoined an observation of Mercury by our author, scil. 



Mercurii Transitus sub Solis Disco. Oct. 28. Anno 1677. Cum Tentamine 



pro Solis Parallaxi. 

 Of his conjectures here made about the sun's parallaxis, in his preface he 

 "says, that were the place of Mercury's node once found, from this his obser- 

 vation of Mercury, the sun's parallaxis might be deduced. 



Hereto are added, by our author. 

 Modi quidam pene Geometrici pro Parallaxi Lunae investiganda. 

 Of which there are three proposed ; of which it is remarked that the best 

 way of finding the same, would be, by comparing the meridian altitudes of the 

 moon, observed both in St. Helena and in Europe at the same time. 



The concluding chapter is entitled, 

 Quaedam Lunaris Theorise Emendationem spectantia. 

 Wherein it is observed that astronomy is at present most of all defective. 

 And that the discovery hereof would lead us to the most exact way of finding 

 the longitude of places. 



