J. N. Lockyer— Existence of Elements in the Sun. = 481 
Now other researches, not yet ti mg ready for publica- 
tion, have led me to the ‘following conclus 
The absorption of some elementary eee compound gases 
is limited to the most refrangible part of the spectrum when 
the gases are rare, and creeps gradually into the visible violet 
part, and finally to the red end of the spectrum, as the pressure 
is increased. 
II. Both the general and selective absorption of the photo- 
spheric light are greater (and therefore the temperature of the 
photosphere of the sun is higher) than has been supposed. 
I. The lines of compounds of a metal and iodine, bromine, 
&c., are observed generally in the red end of the spectrum, and 
this holds good for absorption in the case of aqueous vapor. 
Such spectra, like those of the metalloids, are separated spec- 
troscopically from those of the metallic elements by their col- 
anded structure. 
IV. There are in all probability no compounds ordinarily 
present in the sun’s reversing layer. 
V. When a metallic compound vapor, such as is referred to 
in ITI, is dissociated by the spark, the band spectrum dies out, 
and the elemental lines come in, according to the degree of tem- 
perature employe 
Again, ee ae our knowledge of the spectra of stars is 
lamentably incomplete, I gather the following facts from the 
work already accomplished with marvelous skill and industry 
by Secchi of Rome. 
VI. The sun, so far as the spectrum goes, may be regarded as 
a representative of class (/) oie i between stars (@) with 
much simpler spectra of the sa ae 1 stars (v) with much 
more complex spectra of a didtere tk 
Sirius, as a type of a, is (1) the acne (and therefore 
fetheyy 2 star in our northern sky: (2) the blue end of its spec- 
trum en; it is only certainly known to contain hydrogen, 
hee ottier metallic lines being exceedingly — thus indicating 
a small proportion of metallic e vapors; while (3) the 
lines in this star are enormously distended, Set that the chro- 
mosphere is largely composed of that e 
There are other bright stars of this sine: 
VIII. As types of y the red stars may be quoted, the 
of which are composed of channelled spaces and bands. Hence 
the reversing layers of these stars peobably contain metalloids, 
or compounds, or both, in great quantity ; “ey rh in their spectra 
not only is hydrogen absent, but the metallic ced 
in thickness and intensity, which in the light of Vy ne may 
indicate that the metallic vapors are being associa is fair 
i assume that these stars are of a lower temperature ite our 
un. 
