262 
ME. J. NORMAN LOCKYER ON SPECTRUM-ANALYSIS 
Coincident with all the bright iron lines which he observed with the spark he used (he 
only saw a small number of the lines), he found well-defined Fraunhofer lines. He 
therefore located iron vapour in the atmosphere. The rest of the evidence relating to 
other metals I give from the translation of his memoir by Professor Eoscoe*. 
“ As soon as the presence of one terrestrial element in the solar atmosphere was thus 
determined, and thereby the existence of a large number of Fraunhofer lines explained, 
it seemed reasonable to suppose that other terrestrial bodies occur there, and that, by 
exerting their absorptive power, they may cause the production of other Fraunhofer 
lines ; for it is very probable that elementary bodies which occur in large quantities 
on the earth, and are likewise distinguished by special bright lines in their spectra, will, 
like iron, be visible in the solar atmosphere. This is found to be the case with 
calcium, magnesium, and sodium. The number of the 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 character- 
istic group, which likewise coincides with a remarkable group of Fraunhofer 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 atmo- 
sphere 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 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 f, but was not seen to be the 
case with other equally bright lines of this metal. From my observations I con- 
sider that I am entitled to conclude that nickel is visible in the solar atmosphere ; 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, stron- 
tium, 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 ; 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 I was unable to 
~ Transactions of Berlin Academy, 1861. Translated by Roscoe. Macmillan. f The italics are mine. 
