206 



THE CAUSES WHICH PROPAGATE 



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W 

 EH 



r/3 

 O 

 CO 



!2; 





Ph 



^ a 



o 

 o 



12; 



O 

 O 

 1-1 



m 



. 

 < H 



2S 



^ : O 



is"^ 



-c) 



CO 2 



bC02 





5-.^ o 





^^• 





^^2,^:^-2 



p 03 





3^^^ 6 







S^-i-o 





oro -i O 



?* I- 5 

 C5 



00 C3 



=:! K to 



- S ^ 



3 O 3 





ss 

 <, 



pqS 



a a s 



w S S S M 



w ^ >^ u^ 



o w 



"S IZ; rS 



3 S O Q 



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