SECT. XXXVI. NEBULA ROUND r) ARG1JS. 419 



such the dazzling richness of the starry ground on which they 

 are represented to his gaze." In that portion of the sky there 

 are many fine double stars rich starry clusters ; the elegant 

 cluster of variously coloured stars round K Crucis ; a large 

 planetary nebula with a satellite star ; another of a bright blue 

 colour, exquisitely beautiful and unique ; and, lastly, 77 Argus 

 itself, the most extraordinary instance of a variable star in astro- 

 nomical history. 



It frequently occurred, during Sir John Herschel's survey of 

 the southern heavens, that some parts of the sky were noted for 

 deeper blackness than others, and no stars could be seen; it 

 frequently happened that far from the Milky Way, or any large 

 nebula or cluster of stars, there were some indications of very 

 remote branches of the Milky Way, or of an independent sidereal 

 system or systems, bearing a resemblance to such branches. 

 These were indicated by an exceedingly delicate and uniform 

 dotting or stippling of the sky by points of light too small to 

 admit of any one of them being steadily and fixedly viewed, and 

 too numerous to be counted even if possible to view them. The 

 truth of this existence was felt at the moment of observation ; 

 but the conviction, though often renewed, was not permanent. 

 The places where these appearances occurred are given, in order 

 that those who wish to verify them may have it in their power. 



Such is a brief account of a very few of the discoveries con- 

 tained in Sir John Herschel's great work on the Nebulae and 

 other Phenomena of the Southern Hemisphere, a work which 

 will rise in estimation with the lapse of years. No doubt the 

 form and internal structure of many of these nebulas will be 

 changed by telescopes of higher power ; but as the places of the 

 leading phenomena have been determined, the date of that great 

 work may be regarded as the epoch of nebular time whence the 

 relative changes that take place in the most distant regions of the 

 universe will be estimated for ages to come ; and in the inimit- 

 able writings of the highly gifted father and son the reader will 

 find these subjects treated of in a style worthy of it and of them. 

 Of late years the excellence of the instruments, and still more of 

 the astronomers, in the foreign observatories, have aided the pro- 

 gress of sidereal astronomy immensely. Nor has it been culti- 

 vated with less success in our home and colonial establishments : 

 certainly one of the most remarkable features of the times is the 



