August 19, 1897 J 



NATURE 



;67 



to Sir George Baden Powell's expedition to Novaya that of 1893, their intensities being greater than those 



Zemlya (Figs. 17, i8). of the corresponding Fraunhofer lines. Many of the 



So far as the work has gone, the comparison of the characteristic arc lines of iron also appear in the chrome- 



enhanced lines with the spectrum of the chromosphere sphere, but the presence of the enhanced lines with such 



reveals several facts of importance. In the case of iron, 

 I have already pointed out {Roy. Soc. Proc, vol. Ix. p. 475) 

 that the enhanced lines were all present in the chromo- 

 sphere during the eclipse of 1896, and most of them in 



NO. 145 1, VOL. 56]. 



great intensities indicates that at least in some parts of 

 the chromosphere the temperature of the iron vapour is 

 considerably higher than that of the iron vapour which 

 is most effective in producing the Fraunhofer lines. A 



