vi.] OTHER SOLAR ELEMENTS. 77 



bright lines in the spectrum of each of these metals is, indeed, 

 small } but those lines, as well as the dark ones in the solar 

 spectrum with which they coincide, are so uncommonly distinct 

 that the coincidence can be observed with very great accuracy. 

 In addition to this, the circumstance that these lines occur in 

 groups, renders the observation of the coincidence of these spectra 

 more exact than is the case with those composed of single lines. 

 The lines produced by chromium also form a very characteristic 

 group, which likewise coincides with a remarkable group of Fraun- 

 hofer's lines ; hence I believe that I am justified in affirming the 

 presence of chromium in the solar atmosphere. It appeared of 

 great interest to determine whether the solar atmosphere contains 

 nickel and cobalt, elements which invariably accompany iron in 

 meteoric masses. The spectra of these metals, like that of iron, are 

 distinguished by the large number of their lines ; but the lines of 

 nickel, and still more those of cobalt, are much less bright than the 

 iron lines, and I was therefore unable to observe their position with 

 the same degree of accuracy with which I determined the position 

 of the iron lines. All the brighter lines of nickel appear to coincide 

 with dark solar lines ; the same was observed with respect to some 

 of the cobalt lines, but was not seen to be the case with other equally 

 bright lines of this metal. 1 From my observations I consider that 

 I am entitled to conclude that nickel is visible in the solar atmo- 

 sphere ; I do not, however, yet express an opinion as to the presence 

 of cobalt. 



"Barium, copper, and zinc appear to be present in the solar 

 atmosphere, but only in small quantities ; the brightest of the lines 

 of these metals correspond to distinct lines in the solar spectrum, 

 but the weaker lines are not noticeable. The remaining metals 

 which I have examined, viz., gold, silver, mercury, aluminium, 

 cadmium, tin, lead, antimony, arsenic, strontium, and lithium, are, 

 according to my observations, not visible in the solar atmosphere. 



" Through the kindness of M. Grandeau of Paris, I obtained several 

 pieces of fused silicium, and I was thus enabled, by using them as 

 electrodes, to examine the spectrum of this element. The lines 

 in the silicium spectrum are, however, with the exception of two 

 broad green bands at 1810 and 1830, so deficient in luminosity, that 



1 The italics arc mine. 



