Latitudes of Montjouy and Barcelona. 253 



northern and southern stars, accords with the geodesical mea- 

 surements. 



Happily M. M^chain observed /3 Tauri and Pollux to the south. 

 of the zenith. He has himself expressed regret at his choice of 

 these stars, and still more in having employed ^ Ursae Majoris. 

 With regard, indeed, to the last named star, it was matter of 

 just regret ; but if he still lived, he Avould, without doubt, on 

 the contrary, rejoice, to find that those two stars south of the 

 zenith are the means of preserving the whole work. The several 

 series of Pollux and /3 Tauri, compared with those of the 

 northern stars, show the existence of unsuspected errors in the 

 circle of M. Mechain of the nature of those to which we have 

 alluded. The latitudes observed to the south of the zenith are 

 less than those to the north, and the difference is greater at 

 Barcelona than at Montjouy. But all are in accord by the 

 application of the new method of combination 3 the anomalies 

 disappear ; the latitudes of Barcelona and Montjouy agree, or 

 at least present only the small difference of 0",21, which is well 

 within the limits of probable error of observation, and which it 

 would be an unnecessary refinement to endeavour to remove by 

 further research. 



The following table contains the conclusions in regard to the 

 several stars, and to both the latitudes : — 



MONTJOUY. 



Stars observed « Ursae Minoris, pass, sup. et inf. 326 obs. 41 21 44,91 



north of the i^s Ursae Minoris, pass. sup. et inf. 288 do. 45,21 



zenith. ^ Ursae Majoris, pass. sup. . 82 do. 44,98 



.a Draconis, pass. sup. . 72 do. 47,28 



The four stars . . . 768 obs. 41 21 45,25 



Stars observed [ o / // 



south of the {/STauri, 88 obs. 41 2143,76 

 zenith. I Pollux, 40 do. 43,90 



,The 2 stars, 128 obs. 41 21 43,81 41 21 43,81 



Latitude observed at Montjouy 41 2i_44,53 



APRIL— JULY, 1828. S 



