AMERICAN 



JOURNAL OF SCIENCE AND ARTS. 



[THIRD SERIES.] 



Art. XLY1.—071 the Solar Corona; by Prof. C. A. Yoltxg. 

 of Dartmouth College. 



Although we have not yet official reports from the difi'en • 

 parties who observed the solar echpse of last December, ii 

 perhaps not necessary to wait for them in order to form an k'v 

 of the state in which the problem of the sun's corona nv.. 



From what has already appeared in the scientific and news 

 journals, it is clear that while little new matter has been added 

 to the stock of scientific knowledge, and while some questions 

 are left in a more puzzling condition than ever, yet certain of the 

 conclusions arrived at in 1869, but received with a good deal of 

 feser\'e in certain quarters, have been fully confirmed and 

 placed beyond further reasonable doubt. 

 . J-he polariscopic observations are less accordant and conclu- 

 sive than might be wished ; undoubtedly because at all the sta- 

 tions they were more or less interfered with and complicated hy 

 the presence of clouds or haze. 



t>n the whole, however, they seem to show pretty definitely 

 that a portion of the coronal hght is polarized in radial plaues. 

 ^.iia IS therefore derived, not self-originated— ahnost certainly 

 simple reflected sunlight — though, of course, the polariscope 

 tioes not inform us whether the reflecting particles are near the 

 siin, or the moon, or in our own atmosphere. 



Very perplexing also is the fact that the faint continuous 

 spectrum, which must be in part produced by this polarized 

 component of the corona's light, shows no discoverable traces of 

 tile dark lines of the ordinary sunlight-spectrum. Probably 

 ^- JoDR. Sgc-Thibd Sekies, Vol. I, No. 5.-Mat, 1871, 



