29© POPULAR SCIENCE MONTHLY. 



some were better adapted than others to use as instruments of war 

 and of the chase. Men must also, very early in their development, 

 have noticed the changes that took place in the heavens: the sun 

 by day, the moon and the stars by night; have grouped the stars 

 into little clusters here and there as they seemed rudely to resemble 

 forms of things which they knew, and as some were brighter than 

 the rest; have begun to reckon periods of time according as position 

 of sun and moon varied. In their observation of the heavens no 

 other phenomenon would have attracted as much attention as an 

 eclipse, and for a long time men would have ascribed this occasional 

 phenomenon to the intervention of some supernatural power. In 

 process of time, however, as their observations were made with more 

 care and recorded, some regularity would be noticed in these, as in 

 other phenomena of the skies; and the period of their recurrence 

 being at last approximately known by those more learned than the 

 rest, predictions of eclipses would be made and verified by what would 

 seem to the multitude direct supernatural aid. Hence the earliest 

 scientific records that have come down to us are of eclipses observed, 

 and in time regularly predicted, by the Chaldeans; hence also the 

 reputation that was always given to the Chaldeans of having magical 

 power. Coming down now to the time when men first seemed to 

 have a genuine spirit of scientific inquiry, we find it among the 

 Greeks some five hundred years b. c. Whatever of rudely scien- 

 tific work had been done before, seems to have been for practical 

 or religious purposes. About that time, however, men began to in- 

 vestigate and speculate in order to find out the truth, and soon we see 

 a class of men, known as philosophers, whose one aim was to find 

 out, because they loved, the truth. " What they saw excited them 

 to meditate, to conjecture, and to reason; they endeavored to account 

 for natural events, to trace their causes, to reduce them to principles " 

 (Wliewell). They set about this, too, in no small, narrow way. 

 They wanted to go right to the bottom of things, of everything at 

 once, and to know the great principles, as they called them, of 

 Nature and of life. That was the reason why the actual scientific 

 results of Greek thought, with all its splendid powers, were so meager. 

 Two things are the necessary conditions of science — facts, and the 

 human power of reasoning. Two processes must be carried out in 

 order to yield any scientific result: facts must be patiently accumu- 

 lated, and the mind must set its reasoning powers to work on them. 

 31 was in the first of these that the Greeks were wanting. They did 

 not realize the need of endless patience in learning the details of 

 Nature's way of working. They wished to take in all of Nature 

 with one tremendous sweep of thought. They did a little inves- 

 tigating and a great deal of reasoning. Occasionally, however, we 



