GREAT MEN 

 OF SCIENCE 



A HISTORY OF 

 SCIENTIFIC PROGRESS 



BY 



PHILIPP LENARD 



formerly Professor of Physics and Director of the 



Radiological Institute in the University of Heidelberg 



Nobel Laureate 



Rumford Medallist of the Royal Society of London 



Franklin Medallist of the Franklin Institute of Philadelphia 



TRANSLATED FROM 



THE SECOND GERMAN EDITION 



BY 



Dr. H. STAFFORD HATFIELD 



WrtH A PREFACE BY 



E. N. DA C. ANDRADE 



Quain Professor of Physics 

 in the University of London 



NEW YORK 

 THE MACMILLAN COMPANY 



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