2 94- Mifcellanea Curiofa. 



(he doubts) for this purpofe, and doth pro- 

 pofe, that by the fide of fome Edifice or Moun- 

 tain, at fome Miles diftance, the fetting of 

 fome noted Star (as that of Lucida Lyra) 

 might be obferved at thofe different times of 

 the Year, which might be equivalent to an 

 Inflrument whofe Radius were fo large. 



Which were a good Expedient if Practica- 

 ble ; but I doubt the Denfity of our Atmo- 

 fphere is fo great, as that it will be hard to 

 difcern a Star juft at the Horizon, or even 

 within fome few Degrees of it : And that the 

 Refraction would be there lb great, and lb 

 uncertain, as not to comply with fo curious 

 an Obfervation. 



That which occurred to my Thoughts upon 

 thefe Confiderations, was to this purpofe ; 

 That fome Circumpolar Stars (nearer to the 

 Pole of the Equator than is your Zenith, and 

 not far from the Pole of the Zodiack) ftiould 

 be made choice of for this purpofe. And in 

 cafe the Meridinal Altitude be difcernably 

 different at different times, fo will alfo be 

 their utmoft Eaft and Weft Azimuth, which 

 may be better obferved than their Riling or 

 Setting : And this will be not obnoxious to 

 the Refraction, as is the Meridional Alti- 

 tude } (for though the Refraction do affect the 

 Altitude, yet not the Azimuth at all) \ and 

 we may here have choice of Stars for the pur- 

 pofe \ which in Obfervations from the bot- 

 tom of a Well we cannot have ; being there 

 confined to thofe only which paft very near 

 pur Zenith, though very fmall Stars, 



i 



