Analysis of Iron Meteorites, Siderolites, and Meteoric Stones. 709 
calcium in the Nejed meteorite, and of nickel, barium, and stron- 
tium in that from Obern Kirchen. A line at 4171-2 is described 
as “unknown,” and one at 40351°4 is doubtfully ascribed to iron. 
The former is certainly, and the latter probably, a gallium line, 
wave-lengths 4171°8 and 4082:7. 
The substances which yield spectra in the oxyhydrogen blow- 
pipe, capable of being photographed are those which are easily 
volatilised at a temperature of about 1800°C., as one of us has 
already shown (“‘ Flame Spectra at High Temperatures, Part I., 
Oxyhydrogen Blow-pipe Spectra,’ Phil. Trans., vol. 185, p. 161, 
1894), and they form a very large proportion of the metallic 
elements and their compounds. When examined by this method 
over a wide range in the ultra-violet, most substances yield 
characteristic spectra. 
CoNncLUSIONS. 
1. The composition of different meteoric irons is very similar, 
though the proportions of the constituents differ to some extent. 
2. We find that copper, lead, and silver are common constituents 
of meteoric irons, and that they occur in variable proportions. 
We have already shown that this is the case with iron ores of 
different varieties, and different kinds of manufactured irons. 
3. Gallium is a constituent in varying proportions of all 
meteoric irons, but not of all meteorites. It occurs in one of the 
siderolites we have examined. 
4, Sodium, potassium, and rubidium, are constituents of 
meteoric irons, but only in minute proportions. 
5. Chromium and manganese are found in meteoric stones, 
but not in the irons, though very minute traces of manganese have 
been detected in two of our specimens. 
6. Nickel is found as a principal constituent in all meteorites, 
meteoric irons, and siderolites. Cobalt occurs in the two latter 
varieties only. 
: The chief points of difference between telluric and meteoric 
iron is the absence of nickel and cobalt in any considerable propor- 
tion from the former, and the presence of manganese; while 
meteoric irons contain nickel and cobalt as notable constituents, 
and, except in minute traces, manganese is absent. 
3 F2 
