and positions of ^58 double and triple stars, ^c. 57 



No. CCCCLII. R. A. 4^^ 26™ ; Decl. 16° 8' N. 

 Aldebaran ; Struve, 129 ; VI. 66. 

 Double ; 1st and 20th magnitudes. 



Passy ; January 16, 1825 ; Seven-feet Equatorial. 



Position = 53<» zy' nf-±. | 4 Obs. | DifF. =: 1" 12'. Excessively difficult. 



Distance about a minute and a half by estimation ; observations of distance 

 cannot be procured, the small star being so excessively faint, that it becomes invi- 

 sible under the slightest illumination. The position here given may be liable to an 

 error of one, or two degrees. 



Passy ; January 19, 1825 ; Seven-feet Equatorial. 



1st and 20th magnitudes. 



Position = 54<» 32' w/± | 2 Obs. | Diff. = o'' 36'. Excessively difficult. 



The small star will not bear even the slightest illumination. The night being 

 unusually favourable, I was very anxions to procure, if possible, measures entitled 

 to confidence; and finding all attempts with a power of 179 ineffectual, I applied 

 273 : no advantage however was gained by the change of eye-piece. The observa- 

 tions of position must, I fear, be regarded with distrust, and any of distance with 

 this instrument are altogether impracticable. 



Mean Result. 



Position 53° 49' nf±(6 Obs.); Distance about one minute 

 and a half by estimation; Epoch 1825.04. 



In 1781 the angle was 52° 58' nf. In 1802 it was mea- 

 sured at 54° 8' nf: the present is nearly a mean between 

 them. It is clear therefore that no very sensible motion can 

 exist in this star. According to the proper motions set down 

 in PiAzzi's catalogue, the angle of position should be liable 

 to a slow change in the direction np sf or ^^, amounting how- 

 ever to a quantity hardly cognizable in 40 years. (H.) 



MDCCCXXVI. i 



