TIIK STAR VAULT. II 



an object S404 feel from the pole would move but 733 yards 

 in an hour, and a point close to the pole only twice as fast as 

 the hour hand of a watch. 



The stars have no courses ; they are fixed forever in their 

 places. They are but a permanent background. The sun 

 appears at the equinox, moves in six months through the half 

 of the ecliptic which is above the horizon-equator, then disap- 

 pears at the other equinox, and is seen no more for half a year. 



The moon rises at her appointed time, and not far distant 

 from the point where the sun appears. For about a fortnight 

 she is constantly above the horizon ; then goes down, on the 

 side opposite to her rising. Needless, perhaps, to remind you 

 that during the polar day her beams are lost in those of the sun. 



The planet Mercury and the planet Venus, being inferior 

 planets, will be seen before the sun's yearl}' rising in the con- 

 stellation Pisces, and after his yearly setting in the constella- 

 tion Virgo. The path they trace upon the heavens will be as 

 it is to the ordinary observer upon the earth's surface, a curve 

 far from simple — ^the combined result of their own movement 

 and that of the earth. 



The superior planets may at the appointed times be seen, 

 all through the long polar night, just as they may all through 

 the short terrestrial night. When, namely, they are on the 

 opposite side of the equator to the sun they will be seen ; 

 when the}' are on the same side they will not be seen. 



Now, I wish my observer to move down the meridian 

 toward the equator, still preserving his disconnection with the 

 earth. But if he do so move he will, from causes set forth 

 above, have a wind abeam to contend with, constantly 

 increasing in force until, at our latitude, for instance, it will 

 have a speed of 766 miles per hour, and at the equator a 

 velocity of 1000 miles per hour. He could not endure this. 

 It would tear him into little pieces just as if he had been 

 blown from a gun. So we will suppress the wind as we have 

 suppressed gravity : the one operation being as easy as the 

 other; and we will have him move at will up and down the 



