94 SCIENCE IE" SHORT CHAPTERS. 



that the limits of this paper will not permit me to enter more 

 fully into the bearings of the recent studies of the corona and 

 the prominences upon my explanations of solar phenomena, 

 especially as the differences between the inner and outer corona, 

 which still appear to puzzle astronomers, are exactly what my 

 explanation demands. I must make this the subject of a sepa- 

 ' rate paper, and proceed at once to the next step of the general 

 argument. 



Assuming that such ejections of solid matter are poured 

 from the prominences, to what distances may they travel ? In 

 attempting to answer this question, I avowedly ventured upon 

 dangerous ground, for at the time of writing I only knew that 

 the force of upheaval of the prominences must be enormous, 

 probably sufficient to eject solid matter beyond the orbit of the 

 earth, and even beyond that of Mars. Actual measurements of 

 the eruptive velocity of the solar prominences have since been 

 made, and they are so great as to relieve me of my quantitative 

 difficulty, and show that I was quite justified in the bold in- 

 ference that these eruptions may account for the zodiacal light, 

 the zones of meteors into which our earth is sometimes plunged, 

 and even the outer zone of larger bodies, the asteroids. 



But how, the reader will ask, can such solids, ejected from 

 the sun, acquire orbital paths around him. "We have been 

 taught that the parabola is the necessary path of such ejec- 

 tions." Mr. Proctor has evidently reasoned in this manner, 

 for in last April number of Fraser's Magazine he says that 

 some of my ideas are "opposed to any known laws, physical or 

 dynamical," that "there is nothing absolutely .incredible in 

 the conception that masses of gaseous, liquid, or solid matter 

 should be flung to a height exceeding manifold that of the 

 loftiest of the colored prominences ; whereas it is not only 

 incredible, but impossible, that such matter should in any case 

 come to circle in a closed orbit round the sun." 



More careful reading would have shown Mr. Proctor that I 

 have considered other conditions besides those of the text- 

 books, that the case is by no means one of simple radial pro- 

 jection from a fixed body into free space and undisturbed 

 return. I distinctly stated that " the recent ejections may have 

 any form of orbit within the boundaries of the conic sections," 

 from a straight line returning upon itself, due to absolutely 

 vertical projection, to a circular orbit produced by the 

 tangential projection of such curving prominences as the ram's 

 horn, etc. The outline of the zodiacal light would be formed 



