410 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1924 



surviving. It was used for determining meridian time, especially at 

 night, in order that the observer might then set his water clock, with 

 its 24-hour divisions — a division of the day which thence passed over 

 into Europe in Hellenistic times, whence it was transmitted to us. 



Now Herodotus reports a tradition current in his day (fifth cen- 

 tury B. C), that the Greeks were greatly indebted to Egyptian 

 knowledge. This tradition has in recent times been universally re- 

 jected; but the documents submitted here to-day may serve at least 

 to illustrate the fact that there was much truth in the tradition trans- 

 mitted to us by Herodotus, and that its complete rejection by classical 

 prejudice is unjustifiable. 



The fact that the early Egyptian scientist employed an inductive 

 method as far back as the seventeenth century B. C. does not, how- 

 ever, mean that he had completely banished from his mind all 

 belief in magic or in supernatural forces. This truth has been well 

 demonstrated for later ages by Prof. Lynn Thorndyke in his monu- 

 mental two volumes on the History of Magic and Experimental 

 Science — a work of which America may well be proud. Undoubt- 

 edly the Greek took the longest step in freeing his mind from in- 

 herited religious and traditional prepossessions. Using astronomical 

 observations undoubtedly drawn from Babylonia, Thales predicted 

 a solar eclipse in 585 B. G. Astonishing as it seemed to the Greeks, 

 there is little probability that this feat was an unprecedented 

 achievement. What was unprecedented, however, was the revolu- 

 tionary generalization which Thales based upon his ability to make 

 such a prediction. For he banished the erratic whims of the gods 

 from the skies and discerned the sway of natural law throughout the 

 celestial world. To tear away and fearlessly to trample underfoot 

 beliefs and superstitions which had been sanctified by age-long re- 

 ligious veneration demanded dauntless loyalty to his own intelli- 

 gence. This first supreme enthronement of the human mind was 

 probably the greatest achievement in the career of man. 



We can pay no greater tribute to such Greek thinkers than to 

 recognize that, although they put credulity to rout, they could not 

 banish it altogether. It has survived with extraordinary persist- 

 ence down to the present day, even appearing in the person of a dis- 

 tinguished statesman who once occupied high office in this city. * * * 



In modern times it was of course the tremendous significance of 

 the discoveries of Galileo which most impressively reproclaimed the 

 supremacy of natural law and the sovereignty of the human mind 

 in discerning that law. In this new home of science * which we are 

 now dedicating, there is nothing which more nobly illustrates its 



* The National Academy of Sciences Building. 



