296 POPULAR SCIENCE MONTHLY. 



age could do was to note a few striking resemblances and differences 

 among the animals that roamed the neighboring forests. What 

 could be done in the later age, ay, what the scientific temper of 

 the age demanded, was the most rigidly careful examination of mul- 

 titudes of facts; examination by a trained mind and with all the 

 improved appliances which science and art had given to the world, 

 and then submitted to the searching scrutiny of other trained minds, 

 with like appliances. Or take the last step, verification. In one 

 case it meant finding the effect upon the taste and upon the health. 

 In the other, what it meant may be judged from the account we have 

 of one of Newton's investigations. In applying his hypothesis of 

 gravitation (it was only a hypothesis then) to the motion of the 

 moon, there was a very slight divergence, about two feet a minute, 

 between the time of the revolution of the moon in its orbit, as he 

 calculated it and as he observed it. He was not satisfied until, 

 eighteen years after, on account of an improvement made in the 

 method of taking observations, he was able to obtain what he re- 

 garded as a verification. 



And so what we learn from the history of science is the gradual 

 development of scientific method. Scientific method in the work of 

 Hipparchus meant a very different thing from the scientific method 

 of the Chaldeans. Very different still is the scientific method of 

 studying the heavens to-day. So to an even greater degree is there 

 a difference between the scientific method of studying the earth to- 

 day and as our fathers studied it. It is not merely the multitude 

 of facts that we have learned, nor the marvelous instruments that 

 we have made to aid us in our observations; it is also, and by no 

 means least, this that men all these centuries have been learning 

 to observe, to reason, and to verify. 



We may say that science and scientific method have grown and 

 developed together: the development of one has invariably advanced 

 the development of the other, and, on the other hand, where one 

 has remained stationary, or has retrograded, so has the other. 



History has enabled us to see this other fact also: that the con- 

 ditions which interfered with the growth of science in the past not 

 only interfere with it always, wherever they exist, but to very much 

 the same degree interfere with the free application of scientific meth- 

 od. What those conditions were during one long period of history we 

 saw a failure to realize its importance as compared with questions 

 of conduct; a tendency to comment rather than investigate; a tend- 

 ency to ascribe everything to spiritual agency rather than to natu- 

 ral causes; and lastly, dogmatism. We very well know how, as 

 a matter of fact, those very conditions do interfere with the appli- 

 cation of scientific method to-day. 



