It is well known that yellow is the complementary of blue, and red of green, color, and it struck me that, relating to this subject, the remarks of Mr. Isaac Sharpless, who is an undoubted authority in astronomical matters, are of some importance. Writing from Haverford College Observatory, June 3d, instant, he says: “The question of star colors has been receiving attention from the hand of an English gentleman, W. S. Franks. He has examined carefully the colors of a list of 1893 of the brightest stars, with especial reference to the distribution in the heavens of the different colors. He finds 962 white stars, 614 yellow, 168 orange, 10 red, 15 green, 59 blue, 58 purple and 7, for some reason, have no colors given. He finds that the constellations which contain a large percentage of white stars are in or near the Milky Way, and wherever stars are closely associated together; while the yellow and orange stars are most plentiful in large straggling constellations. “It is well known that a certain kind of spectrum is connected with certain star colors. The yellow stars belong to the class of our sun and include such bright stars as Capella. The white stars, like Vega, have a spectrum of a great number of fine lines, and the red gives a banded spectrum. It has been a favorite theory that the colors indicate the age of the stars, if not in years, at least in development. That the white are the youngest: as they cool they become yellow, then red, and, finally invisible, just as a piece of iron would in cooling down from a white heat. There is much to commend this idea, though, of course, as to the relative ages of the stars we know very little, and some changes appear to be in the opposite direction. Perhaps there are people to whom the idea of different colors in stars is a novelty. They have a general idea that there are bright points of light overhead, at night, and probably they have observed, in a general way, that some are brighter than others. It will not require a very close watch, however, to add to the knowledge of the sky the additional fact that they are differently colored. Castor and Pollux which now shine in the west in the evening, are very evidently diverse, and a careful amateur can go over the heavens and notice among the brighter stars quite a variety.