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the Experiment Station of each state in which fer- 

 tilisers are used extensively, collects samples of the 

 fertilisers offered for sale in that state, and analyses 

 each one to see if it contains as much plant food as 

 the manufacturer claims that it does. If it is found 

 to contain less than the guarantee on the tag 

 specifies, the manufacturer is subject to prosecution. 



The effect of this state supervision of the fer- 

 tiliser trade has been very satisfactory. The 

 general standard of the business has been raised. 

 Each year the Experiment station of each state 

 publishes a bulletin listing all the brands of fertilisers 

 that have been registered for that year, also the 

 guaranteed analysis of each as shown by the 

 manufacturer's tag, and the actual value, as shown 

 by analyses at the Experiment station. Farmers 

 who use fertilisers should get these bulletins. 



Studying Fertiliser Tags. Some of the guaran- 

 tees printed on fertiliser tags are misleading. The 

 real analysis is sometimes obscured by adding to it 

 statements of valueless materials that the fertil- 

 iser contains, and by repeating the real analysis in 

 another form, thus making the buyer who is not 

 skilled in such matters think he is getting more 

 for his money than he really does. Roberts states 

 that the following guarantee was on a fertiliser sold 

 in New York: 



Per cent. 



Total bone phosphate 30 to 35 



Yielding phosphoric acid 14 to 16 



Soluble bone phosphate 22 to 26 



Yielding water-soluble phosphoric acid . . 10 to 12 



Total available bone phosphate 26 to 30 



Available phosphoric acid 12 to 14 



Insoluble bone phosphate 2 to 4 



Yielding insoluble phosphoric acid . . . 1 to 3 



