of Double Stars. i^j 



have now introd'accdand ufed in all the angles of thetollo^ving 



catalogue** 



Datchet nearWindfor, Nov. l, 1784. W. HERSCHEL, 



CATALOGUE 0F DOUBLE STARS. 

 FIRST CLASS.^ 



I. 25. A Ononis. Fl. 32. Sob humero in confequentia. 

 Jan. 20. Double. Confiderably unequal. L. fine w. ; S. w, 



1782. inclining to pale rofe colour. The diftance or black 

 divifion between the two flars with 278 is about \ diar 

 meter of L. % with 460, near | diameter of L. Pofi- 

 tion with 278, 52* 10' f. preceding. 

 26. fti Leonis. Fl. 2. Anteriorem pedem dextrum praecedens. 



Feb. 8. A very minute double ftar. Confiderably unequal. 



1782. Both r. With 227 there is not the leaft fufpicion of 

 its being double; with 460 it appears oblong, and, 

 when perfedly diftin(5l, we fee | of the apparent dia- 

 meter of a fmall ftar as it were emerged from behind a 

 larger ftar ; with 932 they are more clear of each other,, 

 but not feparated ; the focus of every power adjufled 

 upon the o^^ and 6th Leonis.. November 6th, 1782, I 



* The divifion s on the moveable circular index (j) of this micrometer fhould 

 be read off by means of a line drawn on a fmall plate fattened to the fide /, and 

 projeftiag with a proper curvature againft the plane of the divifions towards r, fd 

 as to be nearly in conta<5t; a coincidence of lines being by far the beft method of 

 afcertaining the fituation of the index. A nonius of four fub -divifions may alfo 

 be ufed, whereby the 60 divifions, already divided into halves upon the index- 

 plate, will be had in eighths, each of which, on the conflrudion of my prefcnt 

 one, will be equal to three minutes of a degree of the circle. 



7 firft 



