Royal Society. 127 



tions of some very extraordinary objects, which have not hitherto suf- 

 ficiently engaged the attention of astronomers, and many of which 

 possess a symmetry of parts, and a unity of designs, trongly marking 

 them as systems of a definite nature, each complete in itself, and sub- 

 servient to some distinct, though to us inscrutable, purpose. 



In an Appendix, the author enters into a detailed account of the 

 manner in which the reductions have been executed, and how the 

 numbers set down in the catalogue are concluded from those regi- 

 stered at the moment of observation. For effecting these reductions, 

 he pursued a method materially different, and much more convenient 

 and exact, than he employed to reduce his earlier catalogue of double 

 stars. 



Various remarks are next made on the figured nebulae. It often 

 occurred to the author, to notice a peculiar state of the atmosphere, 

 which is quite independent of fog or haziness, in which all large stars 

 abov'e the seventh magnitude appear surrounded with photospheres, 

 of a diameter of two or three minutes, or even more, and exactly re- 

 sembling those about some of the finer specimens of nebulous stars. 

 These appearances come on suddenly, seldom last long, and disap- 

 pear as unexpectedly as they come : hence the inference is drawn, 

 that the true cause of this phenomenon is atmospheric, and that it is 

 perhaps connected with some highly rarefied material, disseminated 

 in cloud-like, though invisible, masses in the very highest regions of 

 our atmosphere, and possibly the same with that which, when ignited 

 by the passage of electric currents, gives rise to many, if not all, the 

 phenomena of the aurora borealis. Frequent instances occur of the 

 proximity of minute stars to nebulae ; an appearance which naturally 

 suggests the idea of their composing planetary systems : for the enor- 

 mous magnitude of the nebulae, and its consequent probable mass, 

 may, notwithstanding the rarity of its material, give it a gravitating 

 energy, capable of retaining, in orbits three or four times their own 

 diameter, and in periods of great length, small bodies of a star-like 

 character. 



Lastly, the author offers some lemarks on the constitution of ne- 

 bulae which have an elongated or elliptical form, of those which are 

 double, and of those to which the epithets of hairy or Jilumentous have 

 been applied; and considers their relations to ordinary physical laws. 

 Anniversary Meeting, Nov. 30th. 



His Royal Highness the Duke of Sussex, K.G., delivered the fol- 

 lowing Address : — 

 Gentlemen, 



The third anniversary of my election to this Chair affords me 

 again the opportunity of expressing my grateful thanks for the kind- 

 ness which I have continued to receive from you. I would willingly 

 enlarge upon a topic which is so grateful to my feelings, were I 

 not conscious that by so doing I should merely vary the form of 

 phrases which the natural expression of my sentiments prompted me 

 to use when I have before had the pleasure of addressing you, whilst 

 atiments themselves remain not merely unchanged, but, I 

 trust, likewise unchangeable. If I am thus brief, therefore, Gentle- 



