526 Mr. W. Huggins on the Spectra 



104° 28' 52"-5. A planetary nebula. Bright; very small; 

 round.] In Sagittarius. 



This nebula is less bright than those which have been described. 

 The two brighter of the lines were well defined, and were directly 

 compared with the induction-spark. The third line was seen 

 only by glimpses. I had a suspicion of an exceedingly faint 

 spectrum. 



The colour of this nebula is greenish blue. 



Lord Rosse remarks, " Centre rather dark. The dark part is 

 a little north preceding the middle " *. 



(No. 4628. 2098 h. 1 H. IV. R.A. 20 h 56 m 31 s «2. N.P.D. 

 101° 55' 4"*8. An exceedingly interesting object. Planetary; 

 very bright ; small ; elliptic] In Aquarius. 



The three bright lines very sharp and distinct. They were 

 compared for position with the induction-spark. Though this 

 object is bright, an indication only of the faint spectrum was 

 suspected. This nebula contains probably a very small quan- 

 tity of matter condensed into the liquid or solid state. 



The colour of the light of this nebula is greenish blue. 



Lord Rosse has not detected any central star, nor any perfo- 

 ration as seen in some of the other planetary nebulse. He 

 represents it with ansae, which probably indicate a nebulous ring 

 seen edgewaysf. 



[No. 4447. 2023 h. 57 M. R.A, 18 h 48 m 20 s . N.P.D. 

 57° 8' 57"'2. An annular nebula; bright; pretty large; con- 

 siderably elongated.] In Lyra J. 



The apparent brightness of this nebula, as seen in the tele- 



* Philosophical Transactions, 1861, Part III. p. 732. 



f Ibid. 1850, p. 507, and plate 38. fig. 14. 



X Lord Rosse, in his description of this nebula, remarks, " The filaments 

 proceeding from the edge become more conspicuous under increasing mag- 

 nifying-power within certain limits, which is strikingly characteristic of a 

 cluster ; still I do not feel confident that it is resolvable." — Philosophical 

 Transactions, 1844, p. 322, and plate 19. fig. 29. 



In 1850 Lord Rosse further remarks, "I have not yet sketched it with 

 the 6-feet instrument, because I have never seen it under favourable cir- 

 cumstances : the opportunities of observing it well on the meridian are 

 comparatively rare, owing to twilight. It was observed seven times in 

 1848, and once in 1849. The only additional particulars I collect from 

 the observations are that the central opening has considerably more nebu- 

 losity, and there is one pretty bright star in it, s. f. the centre, and a few 

 other very minute stars. In the sky round the nebula and near it there 

 are several very small stars which were not before seen; and therefore the 

 stars in the dark opening may possibly be merely accidental. In the ari- 

 nulus, especially at the extremities of the minor axis, there are several 

 minute stars, but there was still much nebulosity not seen as distinct stars." 

 — Philosophical Transactions, 1850, p. 506. 



"Nothing additional since 1844, except a star s. f. the middle." — Philo- 

 sophical Transactions, 1861, p. 732. 



