SKETCH OF 

 PROF. JOHN LE CONTE 



SENSITIVE FLAMES AND 

 SOUND-SHADOAYS 



BY 



WALTER LE CONTE STEVENS 



PROFESSOR OF PHYSICS IN THF. PACKEK COLLEGIATE INSTITDTE 



TWO ARTICLES 



REPRINTED FROM THE POPULAR SCIENCE MONTHLY 



FOR NOVEMBER, 18S9 



NEW YOKK 

 IJ. APPLE TON AND COMPANY 



1889 



