IIG EXPERIMENT STATION. [Jan. 



past year, ami in iiKist iiistaiices tlic form of potasli was as 

 guaranteed. Tlie misleading practice of stating the sulfate of 

 l)otash equivalent when the potash is actually present in form 

 of muriate is still prevalent to some extent. Every formula has, 

 therefore, been tested to show the form of potash actually 

 present. 



(g) Ground Eoch, Mineral Fertilizer or Stonemeal. 



The indications are that not much of this class of materials 

 has been sold in the Massachusetts markets. The inspectors 

 were not able to find it in the hands of agents, and it was prob- 

 ably sold by the manufacturer through soliciting agents direct 

 to the farmer. 



A sample of Xcw Mineral Fertilizer, manufactured by the 

 'New Mineral Fertilizer Company of lioston, was taken by one 

 of our inspectors from stock carried by the manufacturer. The 

 analysis of this showed the presence of .09 per cent, nitrogen, 

 .38 per cent, total phosphoric acid and .10 per cent water-soluble 

 ])otash. The calculated commercial value of the material was 

 57 cents per ton. Extravagant claims are made by the com- 

 pany for the fertilizing value of the silica, chlorine, sulfur, 

 soda, lime, magnesia, iron and alumina which the material, 

 like all rocks and soils, contains. The ordinary soil usually con- 

 tains an abundance of these elements with the possible excep- 

 tion of lime. Assuming the ton price to be the same as last 

 year, $17, a pound of nitrogen would have cost $5.G7, a pound 

 of insoluble phosphoric acid 60 cents, and a pound of water- 

 soluble potash $1.27. 



Dr. Charles D. Woods, director of the ]\raine Agricultural 

 Experiment Station, has conductxMl field experiments with this 

 material.^ The results of the experiment were stated as follows 

 by Director Woods : — 



"It will be noted that both with the corn and with the potatoes, there 

 was a somewhat smaller yield on the plots to which New Mineral Fer- 

 tilizer was applied than upon the plots Avhich received no fertilizer. 

 The comparative yields seem clearly to point out that there was no 

 benefit from the use of the New Mineral Fertilizer." 



• Seo description of the experiment in tlie American Fertilizer, Philadelphia, Pa., Vol. XXX\'II., 

 No. 9, pp. 28-29. 



