ASTRONOMY WITH AN OPERA-GLASS. 61 



slightly reddish tint. Watch it during the coming winter, and you 

 will see it gradually fade from sight until, at last, only the blackness 

 of the empty sky appears where, a few months before, a conspicuous 

 and brilliant star was seen. Keep watch of that spot next summer, 

 and in July you will perceive Mira shining there again — a mere speck, 

 but slowly brightening — and next fall the wonderful star will blaze 

 out again with renewed splendor. 



Knowing that our own sun is a variable star — though variable only 

 to a slight degree, its variability being due to the spots that appear 

 upon its surface in a period of about eleven years — we possess some 

 light that may be cast upon the mystery of Mira's variations. It 

 seems not improbable that, in the case of Mira, the surface of the star 

 at the maximum of spottedness is covered to an enormously greater 

 extent than occurs during our own sun-spot maxima, so that the light 

 of the star, instead of being merely dimmed to an almost impercepti- 

 ble extent, as with our sun, is almost blotted out. When the star 

 blazes with unwonted splendor, as in 1779, we may fairly assume that 

 the pent-up forces of this perishing sun have burst forth, as in a des- 

 perate struggle against extinction. But nothing can prevail against 

 the slow, remorseless, resistless progress of that obscuration, which 

 comes from the leaking away of the solar heat, and which constitutes 

 what we may call the death of a sun. And that word seems pecul- 

 iarly appropriate to describe the end of a body which, during its 

 period of visible existence, not only presents the highest type of phys- 

 ical activity, but is the parent and supporter of all forms of life upon 

 the planets that surround it. 



We might even go so far as to say that possibly Mira presents to 

 us an example of what our sun will be in the course of time, as the 

 dead and barren moon shows us, as in a magician's glass, the approach- 

 ing fate of the earth. Fortunately, human life is a mere span in com- 

 parison with the aeons of cosmic existence, and so we need have no 

 fear that either we or our descendants for thousands of generations 

 shall have to play the tragic role of Campbell's "Last Man," or be in- 

 duced to keep up a stout heart amid the crash of time by ungener- 

 ously boasting to the perishing sun, whose rays had nurtured us, that, 

 though his proud race is ended, we have confident anticipations of 

 immortality. I trust that, when man makes his exit from this ter- 

 restrial stage, it will not be in the contemptible act of thus kicking 

 a fallen benefactor. 



There are several other variable stars in Cetus, but none possessing 

 much interest for us. The observer should look at the group of stars 

 in the head, where he will find some interesting combinations, and also 

 at the star Chi, which is the little star shown in the map near Zeta {Q. 

 This is a double that will serve as a very good test of eye and instru- 

 ment, the smaller companion-star being of only seven and a half mag- 

 nitude. 



