to the corona seen around the sun during total eclipse." The star afterwards faded away gradually until quite invisible to the naked eye. It will be noticed that none of the above elements--sodium, potassium, or magnesium--are such as would combine with hydrogen to produce the phenomena in question. Professor Proctor concludes, "This evidence seems to me to suggest that the intense heat which suddenly affected this star had its origin from without." He suggests possible meteoric flights; but meteoric stones themselves are separated in space by enormous distances, and these, if converged in orbital flight, would present the same phenomena of successive grazings as a small planet approaching under like circumstances, and by their gradually increasing incandescence we should certainly have other elements visible in the spectroscope besides those observed. And these meteoric bodies, if projected into the sun, would pass in a very brief time through the hydrogen envelope, producing only local phenomena, so that their first blow would be manifested in volatilization of the outer portions of the mass and broad absorption bands, and consequent redness of the planet, exhibiting great heat, but not great light. In such case the bright lines of hydrogen, if they appeared at all, would only be visible as an after-consequence, and not at the earliest moment of conflagration,--that is, the star might grow from red to white, but by no possibility the reverse. It is, however, characteristic of these new stars that their first flash, as it were, is into the incandescence of directly glowing hydrogen, with its bright lines, then through a series of gradually increasing sun-spots, and finally a slow return to their original condition and apparent magnitude. It is obviously a surface phenomenon of the solar atmosphere, primarily, then followed by consequences involving only the outer surface of the solar core, but with no observable permanent change in the character or constitution of the mass of the sun itself. These characteristics are invariable, and the sequence of phenomena is the same in all the cases observed. CHAPTER VII. TEMPORARY STARS, METEORS, AND COMETS.