EXPERIMENT STATION. 7S 



Sohible Fhosjyhoric Acid. — The average retail cost of soluble 

 phosphoric acid in seven samples of the best quality of plain super- 

 phosphate analyzed here during 1881, was 11.1 cts. per lb. Four 

 samples gave the cost at the New Jersey Station at 11^ cts. 



Phosphoric acid in really pure Ground Bone of the spring 

 deliveries, has not, on the average, vai'ied in cost from the Station 

 valuations. 



Insoluble Phosphoric Acid. — Charleston Rock, ground and de- 

 livered, has advanced at wholesale from |;15 per ton in May and 

 June to 116 in October, and to |17 in November. This advance 

 is perhaps largely due to the increased demand during the man- 

 ufacturing season, and it does not appear that phosphoric acid in 

 any of its forms has cost the consumer more than during 1880. 



Potash in Muriate has cost from $3.52 to |4.59 per 100 lbs. 

 retail, in seven samples, the average. having been 14.14; iyi Sid- 

 phate — one sample, the 100 lbs. cost $7.52; in Kainite — 2 sam- 

 ples, the cost of potash per hundred was $8.00 and $7.10, but 

 should not have been more than half these figures judging from 

 the wholesale quotations, viz: $6.50-$9.00 per ton. See p. 51. 



Notwithstanding the increased price of ammonia-salts and of 

 the higher grades of blood and animal matters, the aggregate 

 average cost of the several fertilizing elements in the Nitrogenous 

 Superphosphates and Guanos, good and bad taken together, has 

 during 1881, exceeded the Station valuation by only 9f per cent, 

 as against 12 per cent, in 1880. The advance in cost of this class 

 of goods over the cost in 1880, is also 9| per cent. 



In "Special Manures" the fertilizing elements cost in the aggre- 

 gate average, 8.8 per cent, above the Station valuation, as against 

 10.9 per cent, in 1880. 



The growing demand for nitrogenous fertilizers naturally enhan- 

 ces the prices of the raw materials which enter into their composi- 

 tion and the prospect is that their cost will rather increase than 

 diminish in the future, and it is probable that the Station will be 

 obliged to advance considerably its valuations of the various forms 

 of nitrogen for the year 1882. What ratings it will be proper to 

 adopt for the coming year cannot be now determined. 



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