PLEASURES OF THE TELESCOPE. 201 



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 



Still farther south and nearly in a line drawn from a through 

 (3 we find a remarkable group of double stars, o-, -, p, and 0. The 

 last three form a beautiful little triangle. We begin with o-, the 

 faintest of the four. The magnitudes of its components are six 

 and nine; distance 54", p. 177. In ir the magnitudes are five and 

 nine, distance 3'4", p. 145 ; in p, magnitudes five and eight, dis- 

 tance 3*8", p. 177 (a third star of magnitude seven and a half is 

 seen at a distance of 4', p. 150) ; in o, 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, 

 indluding the remainder of Ophiuchus and Serpens. Beginning 

 with the head of Serpens, in the upper right-hand corner of the 

 map, we find that /?, 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 v is 

 double, magnitudes five and nine, distance 50", p. 31, colors con- 

 trasted but uncertain. In 8 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, a, of magnitude 

 two and a half, has a faint companion of only the twelfth magni- 

 tude, 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. 



Passing eastward, we come again into Ophiuchus, and find im- 

 mediately the very interesting double, A, whose components are of 

 magnitudes four and six, distance V2", p. 45. This is a long-period 

 binary, and, notwithstanding the closeness of its stars, our four- 

 inch should separate them when the seeing is fine. We shall do 

 better, however, to try with the five-inch. 2 2166 consists of two 

 stars of magnitudes six and seven and a half, distance 27", p. 280. 

 2 2173 is a double of quite a different order. The magnitudes of 

 its components are both six, the distance in 1894 1*14", p. 357. It 

 is evidently a binary in rapid motion, as the distance changed 

 from about a quarter of a second in 1881 to more than a second in 

 1894. The star t is a fine triple, magnitudes five, six, and nine, 

 distances 1-8", p. 254, and 100", p. 127. The close pair is a binary 

 system with a long period of revolution, estimated at about two 

 hundred years. We discover another group of remarkable doubles 

 in 67, 70, and 73. In the first-named star the magnitudes are four 



