1)0 SCIENCE IN SHORT CHAPTERS. 



They are all combustible, and, with a few exceptions, the prod- 

 ucts of their combustion would solidify after they were pro- 

 jected beyond the photosphere. Much of the iron, nickel, 

 cobalt, and copper might pass through the fiery ordeal of such 

 projection, and solidify without oxidation, especially when 

 more or less enveloped in uncombined hydrogen. 



It is obvious that, under these circumstances, there must 

 occur a series of precipitations analogous to those from the 

 aqueous vapor of our atmosphere. These gaseous metals, or 

 their oxides, must be condensed as clouds, rain, snow, and 

 hail, according to their boiling and melting points, and the 

 conditions of their ejection. We know that sudden and 

 violent atmospheric disturbance, accompanied with fierce elec- 

 trical discharges, especially favor the formation of hailstones in 

 our terrestrial atmosphere. All such violence must be display- 

 ed on a hugely exaggerated scale in the solar outbursts, and 

 therefore the hailstone formation should preponderate, especial- 

 ly as the metallic vapors condense more rapidly than those of 

 water -on account of the much smaller amount of their specific 

 heat and of the latent heat of their vapors. 



What will become of these volleys of solid matter thus eject- 

 ed with the furious and protracted explosions forming the 

 solar prominences ? In order to answer this question, we must 

 remember that the spectroscope, as recently applied, merely 

 displays the gaseous, chiefly the hydrogen, ejections ; that 

 these great gaseous flames bear a similar relation to the solid 

 projectiles that the flash of a gun does to the grapeshot or 

 cannon-ball. Mr. Lockyer says : " In one instance I saw a 

 prominence 27,000 miles high change enormously in the space 

 of ten minutes ; and, lately, I have seen prominences much 

 higher born and die in an hour. " He has recently measured 

 an actual velocity of 120 miles per second in the movements of 

 this gaseous matter of the solar eruptions, the initial velocity of 

 which must have been much greater.* If such is the velocity 

 of the gaseous ejections, what must be that of the solid pro- 

 jectiles, and where must they go ? 



A cosmical cannonade is a necessary result of the condi- 

 tions I have sketched, and as prominence-ejections are continu- 

 ally in progress, there must be a continual outpouring from the 

 sun of solid fragments, which must be flung far beyond the 



* Subsequent observations (1882) by Secchi, Young, and others 

 have demonstrated velocities far exceeding this ; quite sufficient to 

 project the solid matter clearly beyond the sphere of solar attraction. 



