1884.] Mr. David GUI on the Distances of the Fixed Stars. 91 



WEEKLY EVENING MEETING, 



Friday, May 23, 1884. 



The Earl of Rosse, D.C.L. LL.D. F.R.S. Manager aud Vice- 

 President, in the Chair. 



David Gill, Esq. LL.D. F.R.S. 



Her Majesty's Astronomer at the Cape of Good Hope. 



Recent Besearclies on the Distances of the Fixed Stars, and some Future 

 Problems in Sidereal Astronomy. 



There has ever been a desire to burst aside the constraints im- 

 posed upon our research by the distances of space ; to pass from the 

 study of the planets of our solar system to that of the suns and 

 galaxies that surround us ; to determine the position and relative 

 importance of our own system in the scheme of the universe, and the 

 whence we have come and the whither we are drifting through the 

 realms of space. 



The galaxy or Milky Way — what is it? Is our sun one of 

 its members ? What is the shape of that galaxy ? What are its 

 dimensions ? What is the position of our sun in it ? 



The star-clusters — what are they ? Are these clusters galaxies ? 

 Have these suns real dimensions comparable with those of our sun, 

 and is it distance alone that renders their light and dimension so 

 insignificant to the naked eye ? Or are the real dimensions of the 

 clusters small as compared with our galaxy ? Are their component 

 suns but the fragments of some great sun that has been shattered by 

 forces unknown to us, or have they originated from chaotic matter, 

 which, instead of forming one great whirlpool and condensing by 

 vortex action into one great sun, has been thrown into numerous 

 minor vortices, and so become rolled up into numerous small suns ? 



The nebulaB — what are they ? Are they, too, condensing into 

 clusters or stars, or will their ghost-like forms remain for ever 

 unchanged amongst the stars? or do they play some part in the 

 scheme of nature of which we have as yet no conception ? 



These and many others are the questions which press on the 

 ardent mind that contemplates the subject ; and there arises the 

 intense desire to answer such questions, and, where facts are wanting, 

 to supply facts by fancy. The history of deep and profound thought 

 in some of these subjects goes back through 2000 years, but the 

 history of real progress is but as of yesterday. The foundation of 

 sidereal astronomy may be said to have begun with the art of accurate 

 observation. Bradley's meridian observations at Greenwich about 

 1750, his previous discovery of the aberration of light in 1727, and 

 Herschel's discovery of the binary nature of double stars, his surveys 

 of the heavens, and bis catalogues of double stars — these are solid 



