PIONEERS OF 

 SCIENCE IN AMERICA 



Sfeetcbes of tbeir %i\>es anfc Scientific TKHorfe 



REPRINTED WITH ADDITIONS 

 FROM THE POPULAR SCIENCE MONTHLY 



EDITED AND REVISED BY 



WILLIAM JAY YOUMANS, M. D. 



WITH PORTRAITS 



NEW YORK 



D. APPLETON AND COMPANY 

 1896 



