Page 487 - 89 history of astronomy_opt

to established facts, we learn from the spec-
troscopic researches (1) that the continuous
spectrum is derived from the photosphere
or solar gaseous material compressed almost
to liquid consistency; (2) that the reversing
layer surrounds it and gives rise to black
lines in the spectrum; that the chromosphere
surrounds this, is composed mainly of hy-
drogen, and is the cause of the red promi-
487