08 



gems, red, oranpfo, yellow, blue, green, pnrple, &c. ; many 

 of which are double stars exhibiting beautiful phenomena of 

 complementary colours — yellow and purple, pale green and 

 blue, orange and sea-green, yellow and sapphire blue, &c., &c. 

 Coloured stars are also seen, with a good telescope, in small 

 clusters invisible to the naked eye, such as I Crux, the area 

 occupied by this object is about one-forty-eighth part of a 

 square degree, and when viewed through an instrument of 

 sufficient aperture, the object is extremely beautiful, giving 

 the effect of a rich piece of fancy jewellery. Another such 

 cluster in the same neighbourhood, about half a degree from 

 ■n Argus, the constituent stars of which are equally brilliant 

 and beautiful, is entered in the Cape observations as a neat 

 cluster, but the colours are not named. These stars, either 

 single, double, or in groups, are amongst the most beautiful 

 objects to be seen with the telescope in either hemisphere, 

 and when we consider that the colours of these stars are 

 all produced by the same substances which we are so familiar 

 with in the earth, we are taught that our knowledge of 

 the universe does not depend only on the power of large 

 telescopes, but that the human intellect may become familiar 

 "with things which the human eye cannot see. 



It is known from various reasons that the stars are all suns, 

 more or less chemically composed like our own sun ; many 

 of them are variable, some are known to have disappeared, 

 and have not been seen since. Others, which before were 

 invisible, have appeared, and remained visible since. About 

 two years ago, there appeared a star of the ninth magnitude 

 in the Northern Crown that all at once put on an unusual 

 degree of brightness, and shone equal to a star of the second 

 magnitude. The light of this star was examined by spectrum 

 analysis, from which it was found to have been suddenly 

 enveloped by flames of burning hydrogen. When the hydro- 

 gen was all consumed, the photosphere became less luminous, 

 and the star returned to its former state. 



The question which concerns us is, whether our sun is likely 

 to undergo such a sudden change. The most recent observa- 

 tions show us that masses of hydrogen gas, in combustion, 

 rise from the sun's photosphere many thousand miles in 

 vertical height, and constitute the red prominences seen in 

 total eclipses. If such should be the case with our sun — 

 which the prolonged stability of our system does not justify 

 ns in believing — two opposite effects might naturally ensue. 

 Either the cause which produces the gaseous evolution may 

 gradually diminish so as to lessen the heat radiation ; or 

 this cause may augment and increase the power of the central 

 fire : but in either case it is not certain that life would 



