15° 



POPULAR SCIENCE MONTHLY. 



o 



H 



o 



M 

 ■< 



M 

 > 

 O 



< 



H 

 W 

 U 

 b 



<! 



H 



Eh 

 Z 



O 

 0. 



o 



IS 



z; 



b. 

 O 



(4 



b 



PS 



