THE 



POPULAE SCIENCE 



MONTHLY. 



CONDUCTED BY E. L. AND W. J. YOUMAJSTS. 



VOL. XXIV. 



NOVEMBER, 1883, TO APRIL, 1884. 



NEW YORK : 

 B. APPLETON AND COMPANY, 



1, 3, and 5 BOND STREET. 



1884. 



