SCIENCE PROGRESS 



IN THE TWENTIETH CENTURY 



i 



A QUARTERLY JOURNAL OF 

 | SCIENTIFIC WORK 



I & THOUGHT 



VOL. VII 

 NO. 26. OCTOBER 1912 



EDITORS 



H. E. ARMSTRONG, Ph.D., LL.D., F.R.S. 

 J. BRETLAND FARMER, M.A., D.Sc, F.R.S. 



LONDON 

 JOHN MURRAY, ALBEMARLE STREET, W. 



1912 



