444 Sun Viewing and Drawing. 



that portion of the sun by his rotation above alluded to, had 

 again come round upon the disc. 



But, finally, what are the sun spots — what the faculae — 

 what the photosphere — what, in short, as Mr. Carrington asks, 

 is a sun ? A congeries of difficulties to grapple with ! But 

 let us hope that by means of the rapid march of science in the s 

 departments of chemistry, electricity, spectrum analysis, and 

 what not, the time is not far distant when many of these 

 difficulties will be solved. 



Much depends upon our being able satisfactorily to demon- 

 strate (which seems more and more probable) that the laws 

 which govern terrestrial phenomena are the same as those 

 which prevail upon and within our great central luminary, 

 modified very possibly by the existence of conditions, and even 

 perhaps chemical elements peculiar to himself, as the source 

 and dispenser of light, heat, and life, to the planetary worlds 

 around him. 



This, at least, seems certain — viz., that the solar spots are 

 negative and not positive, if we may so say, in their character. 

 That is, that they are areas on the solar surface, where either 

 the photospheric matter has been swept aside, or where it has 

 subsided and become invisible through a change in its tem- 

 perature and molecular condition; and not actually dark, 

 intervening clouds of condensed, metallic, or other vapour, 

 obscuring simply the subjacent photosphere, as Kirchhoff would 

 have it. Still less we maintain are they (as other theorizers 

 rather than actual observers maintain), scoria, or other hardened 

 masses, capable of being rent asunder, and thus again dis- 

 closing the photosphere below, in the shape of loops, bridges, 

 or promontories. 



The minute and careful observations multiplied by Nasmyth, 

 Dawes, De La Rue, Lockyer, Chacornac, and the writer, place 

 all such theories out of the question. It is far more probable, 

 if not indeed certain, that the bridges, promontories, and specks 

 of more or less brilliant matter, which all the above observers 

 have distinctly seen to traverse the umbrae and even nuclei of 

 solar spots, have either drifted away from the general mass of 

 the surrounding photosphere, or are sometimes portions of 

 photosphere which have only newly condensed and become 

 visible ; other pre-existing portions having, on the other hand, 

 in their turn been seen to subside, apparently, or at any rate 

 to dissolve and melt out of sight; and thus that the matter 

 composing the photosphere may be visible or invisible, accord- 

 ing as it is in the solid, liquid, or gaseous condition. 



Professor Brayley considers it probable that in the photo- 

 sphere, and probably the regions and strata lying below it, 

 solid matter must be continually being produced, dissolved, and 



