27 



DIAGRAM IV. 



Northern Illinois, 224 Towns, 1887. A verage Acreage in Wheat corre- 

 sponding to Grades of Injury to all Crops. 





0 



1 



2 



3 



4 



5 



6 



7 



8 



9 



10 



il 



12 



13 



14 



15 



S6 



17 



18 



19 



20 



1000 













































900 













































800 













































700 













































600 













































500 













A 

































400 

 300 











u 





R 



n 





























200 













































100 













































