ii4 THE WORLD MACHINE 



the sun is the true centre of the stellar sphere, then it follows 

 that, with respect to the distance of the fixed stars, the diameter 

 of the earth's orbit is likewise negligible ; as Coppernicus puts 

 it, it is the " relation of a point to a body, of the finite to the 

 infinite.'' 



This is to all intents the language of Aristarchus, though 

 Coppernicus does not quote him either here or elsewhere. 

 Whether the Alexandrian knew of this simple demonstration 

 of his belief, is buried with his lost treatises. He certainly 

 had the idea in all its consequences. We may believe he was, 

 in all probability, the first of the human race to see the world 

 as it is ; the first adequately to understand what infinitude 

 may mean. 



And if this be true, an injustice to history has been done. 

 Yielding in no wise the honours that time has paid to that 

 patient mind which, in an obscure corner of Poland and through 

 forty years of silence, laboured to set the universe in its order, 

 the system of the planets, if it bear a name, should transmit 

 to posterity not that of Coppernicus but that of his far greater 

 predecessor in the gay capital of the Ptolemies. 



If we may trust Sextus Empiricus, and others who make 

 mention, Aristarchus founded, in some sense, a school. His 

 authority was clearly of the highest, yet in all antiquity he 

 seems to have had but one notable follower, Seleucus of Babylon, 

 who came perhaps a century later. Archimedes did not seem 

 to accept his views ; neither did Eratosthenes, nor the great 

 Hipparchus, nor Poseidonius, nor that Ptolemy the astronomer, 

 whose luck it was, like Aristotle, and with as little worth, to 

 be a standard among men for so many centuries after. What 

 was the reason ? 



One may sometimes meet with a curious statement that 

 Hipparchus had in his hands a means of demonstrating the 

 truth of the Aristarchan theory, but failed to make use of it. 

 This lay in his new method of computing the distance 'of the 

 sun and the moon, and in uniting these with Eratosthenes' 

 measure of the earth. But as the preceding pages have already 

 disclosed, Hipparchus did make use of this method, with the 

 singular result of confirming the surprising though inadequate 

 results of the Alexandrian astronomer. 



Moreover, we have seen that Aristarchus himself, a century 

 or more before, had computed the grandeurs of the sun and the 



