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In figuring the commercial value of a compound fertilizer, a suit- 

 able amount should be added to cover the expenses incurred in the 

 manufacture and sale of the goods. 



The trade value of a fertilizer does not necessarily indicate its ex- 

 act agricultural value. The trade value of a given fertilizer simply 

 shows its cost in our general markets. The agricultural value of a 

 fertilizer shows its capacity in producing certain agricultural crops, 

 and depends not only upon the condition of the fertility of the soil 

 upon which the fertilizer is used, but also upon the physical condi- 

 tion of the soil, the mode of cultivation, the season and the crop to 

 be raised. Experience alone can determine the general fitness and 

 approximate agricultural value of compound commercial fertilizers 

 and fertilizing materials. 



