PLEASURES OF THE TELESCOPE. 795 



four, seven, and eight, distances 2", p. 256, and 7"5", p. 112. 

 Cassiopeia contains many star clusters, three of which are indi- 

 cated in the map. Of these 392 is perhaps the most interesting, 

 as it contains stars of many magnitudes, including a red one of 

 the eighth magnitude, and a ninth-magnitude double whose com- 

 ponents are 8" apart. Not far from the star k we find the spot 

 where the most brilliant temporary star on record made its ap- 

 pearance on November 11, 1572. Tycho Brahe studied this phe- 

 nomenon during the entire period of its visibility, which lasted 

 until March, 1574. It burst out suddenly with overpowering 

 splendor, far outshining every fixed star, and even equaling 

 Venus at her brightest. In a very short time it began to fade, 

 regularly diminishing in brightness, and at the same time under- 

 going changes of color, ending in red, until it disappeared. It has 

 never been seen since, and the suspicion once entertained that it 

 was a variable with a period considerably exceeding three hundred 

 years has not been justified. There is a tenth-magnitude star near 

 the place given by Tycho as that occupied by the stranger. Many 

 other faint stars are scattered about, however, and Tycho's meas- 

 ures were not sufficiently exact to enable us to identify the pre- 

 cise position of his star. If the phenomenon was due to a col- 

 lision, no reappearance of the star is to be expected. 



Camelopardalus is a very inconspicuous constellation, yet it 

 furnishes considerable occupation for the telescope. 2 390, of 

 magnitude five, has a companion of magnitude nine and a half, 

 distance 15", 160. 2 385, also of the fifth magnitude, has a ninth- 

 magnitude companion, distance only 2'4", p. 160. According to 

 some observers, the larger star is yellow and the smaller white. 

 The star I is a very pretty double, magnitudes both six, distance 

 10*4". Its neighbor 2 of magnitude six has an eighth-magnitude 

 companion, distance 17", p. 278. The star 7 of magnitude five is 

 also double, the companion of magnitude eight being distant only 

 1*2*. A glance at star cluster 940, which shows a slight central 

 condensation, completes our work in Camelopardalus, and we 

 turn to Ursa Major, represented in map No. 26. Here there are 

 many interesting doubles and triples. Beginning with 1 we find 

 at once occupation for our largest glass. The magnitudes are 

 three and ten, distance 10', p. 357. In the double star 23 the mag- 

 nitudes are four and nine, distance 23% p. 272. A more pleasing 

 object is o- 2 , a greenish fifth-magnitude star which has an eighth- 

 magnitude companion, distance 2-6", p. 245. A good double for 

 our four-inch glass is , whose magnitudes are four and five, 

 distance 1'87", p. 183. This is a binary with a period of revo- 

 lution of about sixty years, and is interesting as the first binary 

 star whose orbit was determined. Savary calculated it in 1828. 

 Near by is v, a difficult double, magnitudes four and ten and 



