1868.] 



Southern Nebula with the Spectroscope. 



453 



easily found ; but even in the field the faint light could only 



just be recognized. 

 No. 3.531. March 25. ["Very remarkable ; cluster ; w Centauri."] A large 



cluster visible to the eye : spectrum continuous. 

 No. 4066. April 29. [" Planetary ; very small ; round ; quite sharp.] 



(April 5, not seen.) Recognized in telescope as a small 



round planetary nebula: seen without much difficulty in 



spectroscope as a small luminous point ill defined on the 



more refrangible side. 



4-601 



D = 2-55;(±'l)+ •70l=D + 2-l±-l. 

 •63 J 



No. 4083. Aprils. ["Very remarkable; globular cluster; very bright; 



large ; extremely compressed in the middle."] Seen in tele- 

 scope as a slightly oval nebulous ball not very bright 

 (? moonshine). Found with difiiculty in the spectroscope : 

 a faint continuous spectrum of considerable width : no lines. 



No. 4173. Aprils. ["Very remarkable; globular cluster; very bright; 



large ; well resolved."] Seen easily in telescope : looked for 

 two hours in vain with spectroscope. 

 April 13. Spectrum continuous ; compared its appearance with 

 that of a small star close by to make sure ; difference quite 

 marked. 



No. 4183. April 13. ["Cluster; well resolved."] Spectrum clearly con- 

 tinuous. 



No. 4238. April 1 3. [" Remarkable ; globular cluster ; very bright ; very 

 large; irregularly round; well resolved."] A faint conti- 

 nuous spectrum certainly seen, but too faint for more than 

 recognition ; stellar spectrum seen involved. 



No. 4284. Aprils. [" Very remarkable ; planetary ; pretty bright ; very 

 small ; round."] Not seen in telescope. 

 April 17. Not seen in spectroscope, though pretty certainly 

 placed. 



April 24. Linear spectrum seen, though too faint for measure- 

 ment, even for absolute certainty of its character. The 

 light seen, however, was too strictly local to belong to a 

 continuous spectrum of so faint an object, but that is the 

 whole of the evidence. 

 No. 4302. April 17. ["Remarkable; annular nebula; pretty bright; 



small ; round."] (April 6, not seen in telescope.) Not seen 

 in spectroscope, though pretty certainly placed. 

 April 24. No result. A faint object in telescope (200), but of 

 some size. No spectrum, though satisfactorily placed. 

 No. 4355. April 24. [" Very remarkable ; very bright ; very large ; trifid ; 



double star involved."] A very large object with a double 



2 R 2 



