8 



Fig. 2. Photograph showing the action of copper sulphate on barley in the presence 

 of nutrient salts. (March 5th April 19th, 1907.) 



1. Glass distilled water. 



2. Copper distilled water. 



3. 1/12,500 copper sulphate. 



4. 1/25,000 



5. 1/50,000 



6. 1/100,000 



7. 1/250,000 



8. 1/500,000 



9. 1/1,000,000 ,, 



