POINTS IN SPECTROSCOPIC ASTRONOMY.
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that they are absent from the sun. Sir William Huggins epitomises these very interesting results in the striking remark: "It follows that if the whole earth were heated to the temperature of the sun, its spectrum would resemble very closely the solar spectrum."
The science of the last century seems destined to be famous throughout the ages. To biologists it will be the century of natural selection; to physicists it will be the century of the spectroscope.