292 ANNUAL REPORT SMITHSONIAN INSTITUTION, 193 3 



to the line than was possible under the old regime. Practical physics 

 was never more satisfactory; theoretical physics never less so. 



This divergence between theory and practice is not to be under- 

 stood as meaning that practice is being divorced from theory to its 

 own advantage. On the contrary, there never was a time when prac- 

 tice was more closely dependent upon theory than today. New re- 

 searches are almost invariably suggested by theory, and their results 

 in a reasonable number of cases are confirmative of the theoretical 

 prediction. Never was theory more fruitful. If we were totally on 

 the wrong track, would Nature give us the abundant encouragement 

 that she does? " By their fruits ye shall know them." 



The difficulty with modern physical theory is not a lack of con- 

 sistency; that mathematical requirement it possesses in abundance. 

 It is the elusive and unreal nature of its fundamental concepts that 

 gives us pause. But who are we that we should reproach Nature 

 with being unreal? Perhaps the fault lies in our definition of 

 reality, and of that Nature herself is the final and supreme judge. 

 Guided by her answers to a century of experimental question, we 

 have drifted steadily away from the material toward the immaterial 

 in our fundamental concepts. If as a consequence science assumes 

 an aspect of romance, perhaps this is because for the first time in 

 the history of human thinking we have come close enough to reality 

 to catch a glimpse of it. The picture is very different from that to 

 which tradition has accustomed us, but so thought the contempo 

 raries of Columbus and those of Galileo. And if the more closely 

 we study Nature the more romantic she appears, perhaps we are but 

 rediscovering something which the poets have always known and 

 have not hesitated to utter. 



And like the baseless fabric of this vision. 

 The cloud-capp'd towers, the gorgeous palaces, 

 The solemn temples, the great globe itself. 

 Yea, all which it inherit, shall dissolve 

 And, like this insubstantial pageant faded, 

 Leave not a rack behind. We are such stuff 

 As dreams are made on, and our little life 

 Is rounded with a sleep. 



Romance or science — which shall we call it? It matters little, 

 once we have been granted the vision to see that the two are not only 

 consistent but inseparable. 



