L54 Mr. South' s observations of the apparent distances 



No. DXCIX. R. A. 9"" IS"* ; Decl. 7" 1' N. 



Struve, 341 ; Hist. Gael. 273. 

 Double ; equal ; each of the 10th magnitude. 



Passy ; January 17, 1825 ; Seven-feet Equatorial. 



Distance = j,".yZo \ 5 Obs. | Diff. r: o" .^yj. Excessively difficult. 



Passy ; February 5, 1825 ; Seven-feet Equatorial. 



9 J and 10th magnitudes. 



Position = 58' 55^ «i> I 5 Obs. 

 Distance = 3". 450 j 5 Obs. 



Diff: « o''.697} Extremely difficult. 



Passy ; March 2, 1285 ; Seven-feet Equatorial. 



9 th and 9^ magnitudes. 

 Position = 56° 29' nf I 5 Obs. I Diff. = 2° 42' ) ^ ^^ 

 Distance = 3 .251 | 5 Obs. | Diff. = o".336) ^ 



Passjr ; March 26, 1825 ; Seven-feet Equatorial. 



Equal; each of the 10th magnitude. 



Position r: 57° 38' «p or «/ 

 Distance =: 3".S72 



Diff! = o''.6o, I Extremely difficult. 



5 Obs. 

 5 Obs. 



Mean Result. 

 Position 57° 41' np or 5/(15 Obs.); Distance 3*.5i3 (20 Obs.); 



Epoch 1825.13. 



No. DC. R. A. 9^ 19"" ; Decl. 9° 5o' N. 



«^ Leonis ; Struve, 342 ; I. 26. 



Double ; large, white ; small, pale blue. 



Royal Observatory, Paris; March 15, 1825 ; Eleven-feet Achro- 

 matic by Lerebours, having an object-glass of 8.4 English 

 inches clear aperture. 



With a power of 420 the small star is separated half a diameter of the large star ; 

 with 560 three-fourths of a diameter ; with each power the stars are admirably de- 

 fined, and as round as possible : had we any micrometrical apparatus, measures of 

 position and distance might be gotten with the greatest facility. Mons. Bouvard 

 present. Night favourable. 



Whether the Seven-feet Equatorial will enable me to measure this close double 

 star I do not know ; the highest power that can be applied to its present micrometer 

 is 273, which is certainly inadequate to show the star double* 



• By a letter from Mr. Herschel, dated May 14, 1825, 1 find that Mr. Struve 

 has measured this star with his telescope of 9 inches aperture, and 14 feet focal 

 length, made by Fraukhofer. 



