oj Double Stars, 4- 



have now introduced and ufed in all the angles of the following 



catalogue*. 



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



CATALOGUE OF DOUBLE STARS, 

 FIRST CLASS. 



I, 25. A Orionis. Fl. ^2. Sub humero in confequentia. 



Jan. 20. Double. Confiderabiy 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 I dia- 

 meter of L. ; with 460, near | diameter of I^. Pofi- 

 tion with 278, 52® lo'f. preceding. 



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



Feb. 8. A very minute double fl:ar. Confiderabiy unequal. 

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

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

 when perfe6i:ly dillind:, we fee i of the apparent dia- 

 meter of a fmall flar 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 adjufted 

 upon the 3d and 6th Leonis. November 6th, 1782^ I 



* The divilions on the moveable circular index {a) of this micrometer fliould 

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

 projefting with a proper curvature againft the plane of the divifions towards r, fo 

 as to be nearly in contad ; 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 conftrudtion of my prefent 



ene, will be equal to three minutes of a desree of the circle. 



7 firft 



