THE FUEL OF THE SUN. 37 



merely pitted on their surface, but riven to their very cen- 

 tres, moulded and shaped throughout by the whirling hur- 

 ricane of their whole substance. When thus in the centre 

 of a tornado of opposing gravitations the tortured orb would 

 be twisted bodily into a huge vorticose crater, into the 

 bowels of which the aqueous vapor would be dragged and 

 dissociated, and then, entangled with the inner matter of 

 the riven sphere, would be hurled upwards, again to burst 

 forth in an explosion of such magnitude that the original 

 body would be measurably presented as a mere appendage, 

 the rocket case of the flood of fire it had vomited forth. 



The reader must complete the picture. If he will take 

 a little trouble in doing so he will find that it becomes a 

 portrait of one or the other of the nebulas, according to the 

 kind of intergravitating star-cluster from which he starts. 

 I have endeavored to work out some of the details of the 

 nebular conditions in Chapter xx. In Chapter xxi. I have 

 concluded by showing the analogy between a sun and the 

 hydro-electric machine, the sun being the cylinder and the 

 prominences the steam jets. If issuing jets of high-pres- 

 sure steam have the same properties at a distance of 93 

 millions of miles from the earth as upon its surface, the 

 body of the sun and the issuing steam must be in opposite 

 electrical conditions, and furious electrical excitation must 

 result; and if the laws of electrical induction are constant 

 throughout the universe, the earth must be as necessarily 

 subject to solar electrical influence as to his thermal radia- 

 tions. Thus the same reasoning which explains the origin 

 and maintenance of the solar heat and light, the sun-spots, 

 the photosphere, the chromosphere, the sierra, the promi- 

 nences, the zodiacal light, the aerolites and asteroids; the 

 meteorology of the planets and the rings of Saturn, also 

 shows how the electrical disturbances which produce the 

 aurora borealis and direct the needle may originate. 



Electrical theories of the corona and zodiacal light, and 

 their connection of some kind with the aurora borealis, 

 have been put forth in many shapes, but so far as I have 

 learned none afford any explanation of the origin of the 

 electrical disturbance. Without this they are like the vor- 

 tices of Descartes, which explained the movements of the 



