eritable
magic wand in the hands of the astronomer.

Very soon eager astronomers all over the world were putting the
spectroscope to the test. Kirchhoff himself led the way, and Donati and
Father Secchi in Italy, Huggins and Miller in England, and Rutherfurd in
America, were the chief of his immediate followers. The results exceeded
the dreams of the most visionary. At the very outset, in 1860, it was
shown that such common terrestrial substances as sodium, iron, calcium,
magnesium, nickel, barium, copper, and zinc exist in the form of glowing
vapors in the sun, and very soon the stars gave up a corresponding
secret. Since then the work of solar and sidereal analysis has gone on
steadily in the hands of a multitude of workers (prominent among whom,
in this country, are Professor Young of Princeton, Professor Langley of
Washington, and Professor Pickering of Harvard), and more than half
the known terrestrial elements have been definitely located in the sun,
while fresh discoveries are in prospect.

It is true the sun also contains some seeming elements that are unknown
on the earth, but this is no matter for surprise. The modern chemist
makes no claim for his elements except that they have thus far resisted
all human efforts to dissociate them; it would be nothing strange if
some of them, when subjected to the crucible of the sun, which is seen
to vaporize iron, nickel, silicon, should fail to withstand the test.
But again, chemistry has by no means exhausted the resources of the
earth's supply of raw material, and the substance which sends its
message from a star may exist undiscovered in the dust we tread or in
the air we breathe. In the year 1895 two new terrestrial elements were
discovered; but one of these had for years been known to the astronomer
as a solar and suspected as a stellar element, and named helium because
of its abundance in the sun. The spectroscope had reached out millions
of miles into space and brought back this new element, and it took the
chemist a score of years to discover that he had all along had samples
of the same substance unrecognized in his sublunary laboratory. There
is hardly a more picturesque fact than that in the entire history of
science.

But the identity in substance of earth and sun and stars was not more
clearly shown than the diversity of their existing physical conditions.
It was seen that sun and stars, far from being the cool, earthlike,
habitable bodies that Herschel th