102 SCIENCE IN SHORT CHAPTERS. 



the gases above named, display a bright-striped spectrum, 

 provided the intervening non-luminous vapors of the same 

 metals are not sufficiently abundant to obscure them at 

 this particular moment, when only the absolute horizon- 

 line is seen, and the body of the moon cuts off all the inter- 

 vening solar surface, and the lower or denser portion of 

 the intervening super-solar vapors, though, of course, these 

 are not so entirely cut off as the continuous background. 



The reversion of the dark lines therefore reveals to us the 

 stupendous fact that the surface of the mighty sun, which 

 is as big as a million and a quarter of our worlds, consists 

 of a flaming ocean of hydrogen and of the metals above- 

 named in a gaseous condition, similar to that of the hydro- 

 gen itself. 



This fact, coupled with the other revelations of the spec- 

 troscope, which, without the help of an eclipse, reveals the 

 surface outline of the sun, the "sierra" and the "promi- 

 nences" tell us that this flaming ocean is in a state of per- 

 petual tempest, heaving up its billows and flame- Alps 

 hundreds and thousands of miles in height, and belching 

 forth above all these still taller pillars of fire that even 

 reach an elevation of more than a hundred thousand miles, 

 and then burst out into mighty clouds of flame and vapor, 

 bigger than five hundred worlds. 



What does the last eclipse teach us in reference to the 

 corona? Firstly and clearly, that Lockyer's explanation 

 which attributed it to an illumination of the upper regions 

 of the earth's atmosphere must be now for ever abandoned. 

 This theory has died hard, but, in spite of Mr. Lockyer's 

 proclamation of "victory all along the line," it is now past 

 galvanizing. There can be no further hesitation in pro- 

 nouncing that the corona actually belongs to the sun itself, 

 that it is a marvelous solar appendage extending from the 

 sun in all directions, but by no means regularly. 



The immensity of this appendage will be best understood 

 by the fact that the space included within the outer limits 

 of the visible corona is at least*twenty times as great as the 

 bulk of the sun itself, that above twenty-five millions of 

 our worlds would be required to fill it. 



Jannsen says: "I believe the question whether the co- 



