Passing near to the region covered by [map No. 13], we find the remaining portions of the constellations Sagittarius and Scutum Sobieskii. It will be advisable to finish with the latter first. Glance at the clusters 4426 and 4437. Neither is large, but both are rich in stars. The nebula 4441 is a fine object of its kind. It brightens toward the center, and Herschel thought he had resolved it into stars. The variable R is remarkable for its eccentricities. Sometimes it attains nearly the fourth magnitude, although usually at maximum it is below the fifth, while at minimum it is occasionally of the sixth and at other times of the seventh or eighth magnitude. Its period is irregular.
Turning back to Sagittarius, we resume our search for interesting objects there, and the first that we discover is another star cluster, for the stars are wonderfully gregarious in this quarter of the heavens. The number our cluster bears on the [map] is 4424, corresponding with M 22 in Messier's catalogue. It is very bright, containing many stars of the tenth and eleventh magnitudes, as well as a swarm of smaller ones. Sir John Herschel regarded the larger stars in this cluster as possessing a reddish tint. Possibly there was some peculiarity in his eye that gave him this impression, for he has described a cluster in the constellation Toucan in the southern hemisphere as containing a globular mass of rose-colored stars inclosed in a spherical shell of white stars. Later observers have confirmed his description of the shape and richness of this cluster in Toucan, but have been unable to perceive the red hue of the interior stars.
The eastern expanse of Sagittarius is a poor region compared with the western end of the constellation, where the wide stream of the Milky Way like a great river enriches its surroundings. The variables T and R are of little interest to us, for they never become bright enough to be seen without the aid of a telescope. In 54 we find, however, an interesting double, which with larger telescopes than any of ours appears as a triple. The two stars that we see are of magnitudes six and seven and a half, distance 45", p. 42°, colors yellow and blue. The third star, perhaps of thirteenth magnitude, is distant 36", p. 245°.
Retaining [map No. 13] as our guide, we examine the western part of the constellation Capricornus. Its leader α is a naked-eye double, the two stars being a little more than 6' apart. Their magnitudes are three and four, and both have a yellowish hue. The western star is α1, and is the fainter of the two. The other is designated as α2. Both are double. The components of α1 are of magnitudes four and eight and a half, distance 44", p. 220°. With the Washington twenty-six-inch telescope a third star of magnitude fourteen has been found at a distance of 40", p. 182°. In α2 the magnitudes of the components are three and ten and a half, distance 7.4", p. 150°. The smaller star has a companion of the twelfth or thirteenth magnitude, distance 1.2", p. 240°. This, of course, is hopelessly beyond our reach. Yet another star of magnitude nine, distance 154", p. 156, we may see easily.
Dropping down to β, we find it to be a most beautiful and easy double, possessing finely contrasted colors, gold and blue. The larger star is of magnitude three, and the smaller, the blue one, of magnitude six, distance 205", p. 267°. Between them there is a very faint star which larger telescopes than ours divide into two, each of magnitude eleven and a half; separated 3", p. 325°.
Still farther south and nearly in a line drawn from α through β we find a remarkable group of double stars, σ, π, ρ, and ο. The last three form a beautiful little triangle. We begin with σ, the faintest of the four. The magnitudes of its components are six and nine, distance 54", p. 177°. In π the magnitudes are five and nine, distance 3.4", p. 145°; in ρ, magnitudes five and eight, distance 3.8", p. 177° (a third star of magnitude seven and a half is seen at a distance of 4', p. 150°); in ο, magnitudes six and seven, distance 22", p. 240°.
The star cluster 4608 is small, yet, on a moonless night, worth a glance with the five-inch.
We now pass northward to the region covered by [map No. 14], including the remainder of Ophiuchus and Serpens. Beginning with the head of Serpens, in the upper right-hand corner of the [map], we find that β, of magnitude three and a half, has a ninth-magnitude companion, distance 30", p. 265°. The larger star is light blue and the smaller one yellowish. The little star ν is double, magnitudes five and nine, distance 50", p. 31°, colors contrasted but uncertain. In δ we find a closer double, magnitudes three and four, distance 3.5", p. 190°. It is a beautiful object for the three-inch. The leader of the constellation, α, of magnitude two and a half, has a faint companion of only the twelfth magnitude, distance 60", p. 350°. The small star is bluish. The variable R has a period about a week short of one year, and at maximum exceeds the sixth magnitude, although sinking at minimum to less than the eleventh. Its color is ruddy.