664 



Report on Inspection Work of the 



other material coming under our examination; while the cost of phos- 

 phoric acid and potash is exceeded only in the case of wood-ashes. 



COMPOSITION OF WOOD-ASHES AND COST OF PLANT-FOOD. 



In 4 samples of wood-ashes, the following results were obtained. 



Table XII. — Amount and Cost of Phosphoric Acid and Potash in 



Wood-ashes. 



These figures show that the cost of potash and phosphoric acid 

 averages higher than in any other form of commercial material in the 

 market. If, however, the calcium carbonate present were given a 

 value, the cost of the other constituents would be a little lower than 

 the figures above. But it is a fair statement that one can not profit- 

 ably use average wood-ashes as a source of plant-food when the price 

 is over $10 a ton. 



AMOUNT AND COST OF PLANT-FOOD IN FISH SCRAP. 



The supply of fish-scrap is limited and the prices are higher than 



formerly. The following data apply to the few samples examined by 



us. 



Table XIII. — Amount and Cost of Nitrogen and Phosphoric Acid in 



Fish -scrap. 



Highest. 



Lowest. 



Average. 



Pounds of nitrogen in 100 pounds 



Pounds of phosphoric acid in 100 pounds 



Selling price of one ton 



Commercial valuation of one ton 



Cost of one pound of nitrogen 



Cost of one pound of phosphoric acid 



9.75 



7.30 



$47.40 



49.72 



24 cents 



4.3 cents 



7.91 



5.67 



$43.00 



40.12 



21.4 cents 



3.8 cents 



8.84 



6 50 



$45 00 



44.98 



22.5 cents 



4.1 cents 



