1913.] PUBLIC DOCUMENT — No. 31. 109 



$50.70, and {]w average commercial valuation calculated by tlio 

 table of trade values has been $rjl.O;> per ton. The pound 

 price of nitrogen from this source has been 1G.39 cents. 



Six analyses of sulfate of ammonia have been made, repre- 

 senting 7 samples; all have been found of good quality. The 

 average retail cash price per ton has been $71.13, and the cal- 

 culated commercial valuation, $72.28 per ton. The average cost 

 of a pound of nitrogen in this material has been 16.23 cents. 



(2) Materials furnisliing PotasJi. — Eighteen analyses of 

 high-grade sulfate of potash have been made, representing 31 

 samples. The average retail cash price of this potash salt has 

 been $50.78, and the average commercial valuation calculated 

 from the table of trade values has been $51.47 per ton. The 

 pound of actual potash in this form has cost on the average 

 5.18 cents. 



Eive analA'ses of potash-magnesia sulfate have been made, 

 representing 9 samples. The average retail cash price has been 

 $29.50, and the average commercial valuation calculated from 

 the table of trade values has been $28.80 per ton. The pound 

 of actual potash in this form has cost 5.38 cents. 



An article offered as double sulfate of magnesia and potash 

 was not hona fide, but evidently high-grade sulfate of potash 

 and sulfate of magnesia reduced with sand. It contained 21.6 

 per cent, material insoluble in hot water, the greater part of 

 which was unquestionably sand. The case is probably similar 

 to several which were detected last year, and which proved to 

 be cases where the mines in Germany had reduced high-grade 

 sulfate of potash with sand in order to fill orders for potash- 

 magnesia sulfate, of which there was a temporary shortage. 

 Dr. Huston, of the German Kali Works, states that the practice 

 is not tolerated by his company, and heavy shipments have been 

 returned at the expense of the mines furnishing the material, 

 and in all cases where this practice has been detected heavy fines 

 have also been imposed. The amount of material involved in 

 this particular case was not large, only ll/> tons being bought 

 by one party for his own use. 



Fifteen analyses of muriate of potash have been made, repre- 

 senting 31 samples. The potash guarantee was maintained in 



