T II E 



POPULAK SCIENCE 



MONTHLY. 



CONDUCTED BY E L. AJVD W. J. YOUMANS. 



VOL. XXX. 



NOVEMBER, 1886, TO APRIL, 1887. 



NEW YORK : 

 D. APPLETON AND COMPANY 

 1, 3, and 5 BOND STREET. 

 1887. 



