PLEASURES OF THE TELESCOPE. 521 



scope may perfectly separate them so far as the stellar disks are 

 concerned. Then, too, I have observed in my own experience 

 that a very faint and close double is more difficult than a brighter 

 pair not more widely separated, usually on account of the defect 

 of light, and this is true even when the components of the faint 

 double are of equal magnitude. 



2 470, otherwise known as 32 Eridani, is a superb object on ac- 

 count of the colors of its components, the larger star being a rich 

 topaz and the smaller an ultramarine; while the difference in 

 magnitude is not as great as in many of the colored doubles. The 

 magnitudes are fifth and seventh, distance 67", p. 348. The star 

 y, of magnitude two and a half, has a tenth-magnitude companion, 

 distant 51", p. 238. 2 516, also called 39 Eridani, consists of two 

 stars of magnitudes sixth and ninth, distance 6'4", p. 150"; colors, 

 yellow and blue. The supposed binary character of this star has 

 not yet been established. 



In o a we come upon an interesting triple star, two of whose com- 

 ponents at any rate we can easily see. The largest component is 

 of the fourth magnitude. At a distance of 82", p. 105, we find a 

 tenth-magnitude companion. This companion is itself double, 

 the magnitudes of its components being tenth and eleventh, dis- 

 tance 2*6", p. 98. Hall says of these stars that they " form a re- 

 markable system." He has also observed a fourth star of the 

 twelfth magnitude, distant 45" from the largest star, p. 85. This 

 is apparently unconnected with the others, although it is only 

 half as distant as the tenth-magnitude component is from the 

 primary. 2 590 is interesting because of the similarity of its two 

 components in size, both being of about the seventh magnitude, 

 distance 10", p. 318. 



Finally, we turn to the nebula 826. This is planetary in form 

 and inconspicuous, but Lassell has described it as presenting a 

 most extraordinary appearance with his great reflector a circu- 

 lar nebula lying upon another fainter and larger nebula of a simi- 

 lar shape, and having a star in its center. Yet it may possibly be 

 an immensely distant star cluster instead of a nebula, since its 

 spectrum does not appear to be gaseous. 



Prof. O. C. Marsh regards the discovery of the Pithecanthropus erectus in 

 Java as an event equal in interest to that of the Neanderthal skull, and believes 

 that no one can doubt that still other intermediate forms will eventually be 

 brought to light. Nearly twenty years ago he placed on record his belief that 

 such missing links existed, and should be looked for in the caves of the later Ter- 

 tiary of Africa. The first announcement, however, has come from the East, where 

 large anthropoid apes still survive, and where their ancestors were doubtless en- 

 tombed under circumstances favorable to early discovery. The tropical regions of 

 both Asia and Africa still offer most inviting fields to ambitious explorers. 



VOL. XLVII. 43 



