THE 



POPULAE SCIENCE 



MOI^THLY. 



CONDUCTED BY K L. AND W. J. YOUMANS. 



VOL. XXVIII. 



NOVEMBER, 1S85, TO APRIL, 1886. 



Is^EW YOEK : 

 D. APPLETON AND COMPANY 



1, 3, A.VD 5 BOND STREET. 

 1886. 



