1 9 8 Mifcellanea Curio fa. 



preferred from being difordered in the Inter- 

 vals of the Obfervations } and difcover at 

 once, both, that there is a Parallax, and 

 that the fixed Stars are at different distan- 

 ces from us, wherein, that I be not mifta- 

 ken, my meaning is not, that the Inftrumtnt 

 or Micrometer fhould be removed for the 

 obferving of the lelfer Star ; but that (when 

 the Azimuth of the greater Star is taken) 

 by a Micrometer (confiiting of divers fine 

 Threads parallel and tranfverfe) may (at the 

 fame time) be obferved the Diftance of the 

 two Stars, each from other, in that Pofiti- 

 on (both being at once within the reach of 

 the Micrometer ;) which diftance (the In- 

 ftrument remaining unmoved) if it be found 

 (at different times of the Year) not to be 

 the fame , this will prove, th3t there is a 

 difierem Parallax of thefe two Stars. 



This latter part of the Obfervation (of 

 their different diftances at different times) 

 I fugged, as more eafily pra&icable though 

 not fo nice as the former. For it may be done 

 I think, without any further Apfaratas there 

 than a good Telefcope, of ordinary form, 

 furnifhed with a Micrometer, (this being 

 carefully kept unvaried' during the Interval 

 of thefe Obfervations. And if this part only 

 of the Obfervation (without the other) be 

 purfued ; it matters not though the two Ob- 

 fervations (near the two SolfticesJ be, one at 

 the Eaftern, the other at the Weftern Azi- 

 muth (whereby both may be taken in the 

 Kight-time,) for the diftance muft (at both 

 Azimuths) be the fame, if after obferving 

 the Azimuth of the greater Star it be ne- 



cef» 



