ME. "W. HUGGINS ON THE SPECTEA OF SOME OF THE NEBULA. 389 



" The outer nucleus unquestionably spiral with a twist to the left." — Lord RossE*. 



" Both nuclei resolved ; brighter parts of spiral branches suspected to be resolved. 

 Stars innumerable, though I feel satisfied that it is not a cluster." — Lord Oxmantown. 



"Nos observations n'accusent aucun changement dans la position relative des deux 

 tetes dans I'intervalle de 13 ans." — O. SiRUVEf. 



Each of the bright centres brought successively upon the slit. Spectrum continuous. 

 A suspicion that some parts of the spectrum were abnormally bright relatively to the 

 other parts. 



[No. 2841. 1175 h. 43 H. V. RA. 12'' i2"'l»-7. N.P.D. 4r55'40"-6. Very bright; 

 very large ; suddenly brighter in the middle ; bright nucleus.] 



"A very large bright extended nebula; much mottled." — Lord EosskJ. 



Spectrum continuous. A suspicion of unusual brightness about the middle part of 

 the spectrum. 



[No. 3474. 1570 h. 63 M. R.A. 13'' 9'" 31»-9. N.P.D. 47° 13' 45"-3. Very bright; 

 large ; very suddenly much brighter in the middle ; bright nucleus.] 



"Spiral? darkness south following nucleus." — Lord RossE§. 



Spectrum continuous. 



[No. 3636. 1663 h. 3 M. R.A. 13»' SS™ 40'. N.P.D. 60° 55' 6". Cluster ; extremely 

 bright.] 



"Ein leicht aufloslicher Hauf zahllosen Sterne, in derMitte zu einem einzigen Lichte 

 von grosser helligkeit zusammenlaufend." — D' Arrest || . 



Spectrum continuous. 



[No. 4058. 1909 h. 215 H. L R.A. 15''2'°36'-3. N.P.D. 33°4r39"-4. Very bright; 

 considerably large ; gradually brighter in the middle.] 



" None of the component stars to be seen. Eesolvability strongest near nucleus." — 



Lord OXMANTOWN. 



Spectrum continuous. 



[No. 4159. 1945 h. R.A. 15'' SS'" 49^-9. N.P.D. 81° 31' 23"-2. Star 7th mag. in pho- 

 tosphere.] 



No unusual appearance was detected in the continuous spectrum of the star. 



[No. 4230. 1968 h. 13 M. R.A. 16'' 36'" 41'-2. N.P.D. 53° 16' 19"-4. Cluster; 

 extremely bright.] 



Spectrum of the central blaze continuous. Spectrum ends abruptly in the orange. 

 The light of the brighter part is not uniform ; probably it is crossed either by bright 

 lines or by lines of absorption. 



[No. 4238. 1971 h. 12 M. R.A. 16'' 39'" 58'-l. N.P.D. 91° 41'47"-4. Cluster; very 

 bright.] 



" Hairy branches with slightly spiral arrangement." — Lord Oxmantown. 



* Philosophical Transactions, 1861, p. 728 ; also ibid. 1850, Plate XXXV. fig. 1. 

 t Bulletin de I'Academie Imp. des Sciences de St. Petersbourg, torn. vii. p. 361. 

 i Philosophical Transactions, 1861, p. 725. § Ibid. p. 729. 



II Beobachtungen der Nebelflecken und Stemhaufen, p. 338. 

 MDCCCLXVI. 3 H 



