POPULAR LECTURES 



ON 



SCIENTIFIC SUBJECTS 



HERMANN VON HELMHOLTZ 



TRANSLATED BY 



E. ATKINSON, PH.D., F.C.S. 



FORMERLY FKOKESSOB OF EXPERIMENTAL SCIENCE, 8TAJ 1 ? COLLEGE 



SECOND SERIES 



WITH AN AUTOBIOGRAPHY OF THE AUTHOR 



LONGMANS, GEE EN, AND CO. 



39 PATERNOSTER ROW, LONDON 



NEW YORK, BOMBAY, AND CALCUTTA 



1908 



All rights reserved 



