458 The Fuel of the $un. [October, 



prominences is that of a palm-tree or bursting rocket, is 

 greatly strengthened.* 



In a paper by P. Secchi, dated Rome, March 20, 1871, and 

 published in the " Comptes Rendus," March 27, this veteran 

 solar observer speaks of the prominences as composed of 

 jets, which, " upon reaching a certain elevation, stop and 

 whirl upon themselves, giving birth to a brilliant cloud." 

 This cloud is represented as spreading out on all sides from 

 the summit of the combined jets. Again he says, " It 

 is very common to see a little jet stop at a certain elevation 

 above the chromosphere, and there spread itself out into a 

 wide hat (' un large chapeau') of an absolutely nebulous con- 

 stitution." This outspreading nebulosity is the flash of the 

 incandescent vapours of the explosion which is theoretically 

 demanded, by my explanation of the constitution of the 

 sun, to occur exactly in the manner and place described. 

 These will be rendered visible by the spectroscopic dilution 

 of the continuous spectrum, while the solid projectiles that 

 must proceed from them in every direction can only be seen 

 during a solar eclipse. 



The observations and drawing of Zollner and Respighi 

 were, for the most part, made while my book was in the 

 press, and like those of Secchi above quoted, were unknown 

 to me when I wrote, and I was then only able to quote, in 

 support of my theoretical requirements, the evidences of 

 actually observed tangental ejection afforded by Sir John 

 Herschel's account of the great solar storm of September 1, 

 1859 ; but the special prominence which I have given to 

 this and the rate of horizontal motion there measured, should 

 have prevented Mr. Proctor from making the mistake 

 he has in the article above referred to. 



Besides this direct tangental projection there are other 

 elements of motion contributing to the same result, such as 

 the whirling of the prominences on themselves, their motion 

 of translation on the sun's disc, and the rotation of the sun 

 itself. 



I must now bring this sketch to a close by stating that in 

 order to submit the fundamental question of an universal 

 atmosphere to an experimentum cruets analogous to that by 

 which Pascal tested the atmospheric theory of Torricelli, I 



* Any reader of " The Fuel of the Sun " will perceive that the vaporous enve- 

 lope which I have described as " an effectual jacket for limiting the amount of 

 radiation," is a complete theoretical anticipation and explanation of the "solar 

 crust " of Respighi and the " Trennungschicht " of Zollner. We agree per- 

 fectly in our conclusions, though arriving at them by such very different paths, 

 and so independently of each other. 



