Page:Popular Science Monthly Volume 46.djvu/315

Rh of ninth-magnitude stars that it contains. We should use the five-inch for all of these.

Canis Minor and the Head of Hydra are also contained on map No. 3. Procyon, α of Canis Minor, has several minute stars in the same field of view. There is, besides, an invisible companion which no telescope has yet revealed, but which must be of immense mass, since its attraction causes perceptible perturbations in the motion of Procyon. One of the small stars just referred to, the second one east of Procyon, distant one third of the moon's diameter, is an interesting double. Our four-inch may separate it, and the five-inch is certain to do so. The magnitudes are seventh and seven and a half or eighth, distance 1⋅2″, p. 133°. This star is variously named Σ 1126 and 31 Can. Min. Bod. Star No. 14 is a wide triple, magnitudes sixth, seventh, and eighth, distances 75″, p. 65°, and 115″, p. 154°.

In the Head of Hydra we find Σ 1245, a double of sixth and seventh magnitudes, distance 10·5″, p. 25°. The larger star shows a fine yellow. In e we have a beautiful combination of a yellow with a blue star, magnitudes fourth and eighth, distance 3·4″, p. 198°. Finally, let us look at θ for a light test with the five-inch. The two stars composing it are of the fourth and twelfth magnitudes, distance 50″, p. 170°.

The brilliant constellations of Gemini and Taurus tempt us next, but warning clouds are gathering, and we shall do well to house our telescopes and warm our fingers by the winter fire. There will be other bright nights, and the stars are lasting.

, when traveling, could never pass a quarry without stopping and examining it. On one journey the mare he rode "soon learned her duty, and seemed to take an interest in her master's pursuits; for she would remain quiet, without any one to hold her, while he was examining sections and strata, and then patiently submit to be loaded with the specimens collected. Ultimately she became so accustomed to the work that she invariably came to a full stop at a stone quarry, and nothing would persuade her to proceed until the rider had got off and examined, or, if a stranger to her, pretended to examine, the quarry."