WITH A FOURTEEN FEET REFLECTOR. 



207 



Sir J. F. W. Herschel. Second Catalogue " of 295 new Double and Triple Stars, discovered in the 

 course of a series of Observations with a twenty feet Reflecting Telescope. Mem. Ast. Sac, Vol. 

 III., Part I., 1827. 



No. 



E. A. 1830.0 



N. P. D. 1830.0 



Angle. 



Quadrant. 



Dist. 



Mags. 



Remarks. 





17" 52'- 1'.5 



113° 2' 2" 



60° 



s p 



10" 



9,10' 



A most curious and interesting object; a double star 

 placed exactly in the central (a) vacuity of a large 

 irregular nebula, which appears to have broken up 

 into three portions by three rifts, or cracks, extend- 



le double star. Twice observed in R. A., and three 



indS. 379. (61°45*sp, 10".952.) 





ing from its centre to its circumference, and whose directions meet (b) at t 

 times in P. D. aR-A. = 7s.l. Diff. of greatest and least P. D. = 84" . H. ; 



Sir J. F. W. Herschel, in the prefatory remarks to the same paper, says: 



The curious double star R. A. IT*" 52" 1^.5, so remarkably situated " vvliere three ways meet," in the 

 midst of a very large and conspicuous nebula, affords a striking instance how easily the latter class of ob- 

 jects may be overlooked in the usual mode of conducting astronomical observations within doors, with 

 lights burning and the field illuminated. Mr. South measured this star in the five feet equatorial, but the 

 nebula which formed so very striking an appendage to it escaped his notice entirely, &c. 



Sir J, F. W. Herschel. "Fifth Catalogue of Double Stars observed at Slough, in the years 1830 and 

 1831, with the twenty feet Reflector, <J-c." 3Iem. Ast. Soc, Vol. VI., 1833. 



No. ft. 



E. A. 1830.0 



fn" 51" 56^9 



J 

 1 



N. P. D. 1830.0 



113° 1' 29" 



Pos. 



218°.0 

 22 .5 



5 216 .4 

 \ 20 i 



Dist. 



10- 

 3 



14 



5i 



Mag 



8, 9.10= 

 8, 10 



Remarks. 



Beautifully triple In nebula IV. 41. 

 Daylight observation; nebula not observed. 



Position, mean of SIB^.O, 217°.l, 216°.2. 

 Triple. Before the close star could be mea- 

 sured, it clouded. 



Svi'eep. 



275^ 



276 



Reference. 



S h. 379, 



Position from diagram. If the rough measure of S A. 379 could be relied upon, the star B must have varied in position greatly. (f) C over- 

 looked by my father, and by S A. 



Sir J. F. W. Herschel. " Observations of Nebula and Clusters of Stars, made at Slough, with a 

 twenty feet Reflector, between the years 1825 and 1833." Phil. Trans. 1833, Part II. 



No. 



Synonym. 



A. E. 1830.0 



N. P. D. 1830.0. 



Description and Eemarks. 



Sweep. 



1991 



IV, 41. 



17" 51"> 56^.9 

 62.4 



64.3 



113° 1' 29" 

 41 



6 

 43 



The double star S h. 379 in the centre^ of the trifid 

 nebula IV. 41. (See my 5th catalogue of double 

 stars. Mem. Roy. Ast. Soc. and fig. 80.) 



A careful drawing taken, but the nebula is not clear 

 from twilight and clouds. (N. B. This drawing 

 is unfortunately lost, and that engraved in fig. 80 

 is constructed from much less elaborate sketches, 

 aided by memory.) 



Very large; trifid, three nebute with a vacuity in the 

 midst S in which is centrally situated' the double 

 star S h. 379, nebula = 7' m extent. A most re- 

 markable object. 



Seen in its place, but clouds prevented observation. 



275t 

 32 



30 

 31 



b Art. 17, Aug. 9; Art. 43. 4. f Art. 62. 



* There is an erratum here in the Mem. Ast. Soc. For " 81° 45','' read " 61° 4.5'." 



t Should it not be 276.' There is an erratum either here or in the catalogue referred to, since against " sweep 

 275" in that catalogue is the remark " Daylight observation; nebula not observed." 



