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cluding Sirius, Vega, Regulus, Altair. The
characteristic feature of their spectra is the
strength and breadth of the hydrogen lines
and the extreme faintness of the metallic
lines. This class of star is white to the eye,
and rich in ultra violet light.
The second class includes about three-
eighths of his stars, including Capella, Pol-
lux, and Arcturus. These stars give a spec-
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