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SMITHSONIAN INSTITUTION  559 
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MADE BY BAKER-VAWTER CO. 
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here in order to measure the heat in the spectrum of the brighter stars. In other words, they attempted to investigate the distribution of radiation in the stellar spectra with the bolometer as they have long done with regard to the spectrum of the sun. When one thinks of taking the light of a star, which looks like a firefly up in the sky, separating it out into a long spectrum, and observing the heat in the different  parts of the spectrum, it seems a practical impossibility. Nevertheless, the observers succeeded in doing this for ten of the brighter stars, and they also observed the sun's spectrum with the same apparatus. In this way it was possible to represent the distribution of radiant energy in the different types of stars from the bluest to the reddest ones, and to know the displacement of the maximum of energy from shorter to longer wave-lengths as the color of the stars tended more and more towards the red.

The outlook for further investigations of this kind is hopeful, and it will have a notable value in the estimation of the temperatures of the stars and the study of stellar evolution.

The two field stations at Mr. Harqua Hala, Arizona, and Mt. Montezuma, Chile, are continued in operation. A notable case of fluctuation in the solar radiation has recently been reported from the Arizona station. A fall of five per cent in the solar heat occurred, beginning about the 15th of October and reaching its minimum on the 21st, and then quickly recovering to the normal by the 25th. By inquiry at the U. S. Naval Observatory, it is learned that a very notable new group of sunspots was formed, the first indications appearing about the 17th of October and the group reaching great dimensions by the 21st when it neared the limb of the sun and shortly disappeared over the edge, due to the solar rotation. This occurrence is nearly parallel to that of March 1920 when a similar great drop in the solar heat occurred and a very extraordinary sunspot group passed over the sun.

[[underlined]] Heat of the Stars [[/underlined]]

The sun is [[underlined]] 93 million [[/underlined]] miles away. Light comes from the sun in eight minutes, travelling [[underlined]] 186 thousand [[/underlined]] miles a second. A light year is the distance light
[[initialed]] CDW [[/initialed]]