COSMIC PHILOSOPHY 



between two remote points on the earth's sur- 

 face, as for example London and Cape Town ; 

 and then from each of these points he proceeds 

 to take the bearings of the moon. The process, 

 indeed, is here compKcated by the fact that, ow- 

 ing to the long distance, the inequalities of the 

 earth's surface, and its curvature, the observer 

 at Cape Town cannot see the position of Lon- 

 don, and vice versa. It is necessary, therefore, 

 again to resort to an indirect method, and, 

 having measured the meridional bearings of the 

 moon from the north pole at London and from 

 the south pole at Cape Town, to compare these 

 bearings with the knowledge that the bearing of 

 the one pole from the other is i8o degrees or 

 two right angles. A further correction must be 

 made for the fact that London and Cape Town 

 are not on the same meridian. But disregarding 

 these steps in the process, as unnecessarily com- 

 plicating our case, we have to note that, when 

 the astronomer has thus indirectly measured 

 the angles which ideal lines drawn to the moon 

 must make at the two ends of his long base 

 line from London to Cape Town, he is at 

 once enabled, like the land surveyor, to calcu- 

 late by trigonometry the lengths of these ideal 

 lines, and thus to ascertain the moon's distance. 

 What, now, is the essential characteristic of the 

 process which the astronomer goes through ? Or, 

 in other words, what is the fundamental psy- 

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