BUREAU OF SOILS. 241 



but also striking inconsistencies between tlie quotations of dealers 

 in adjacent counties and even in different parts of the same county, 

 the disparity being much greater than could be explained away on 

 the ground of differences in freight rates. 



It'is believed that the publication of the information has tended to 

 equalize prices, or at least has put the farmer on his guard and shown 

 him that he can save much in the cost of fertilizer by judicious 

 purchasing. 



Studies of the fertilizer trade also have been concerned with exist- 

 ing methods of computing the cost of manufacture, of establishing 

 wholesale prices, and of providing for distribulion. 



NITROGEN INVESTIGATIONS. 



Work has been continued on the fixation of atinospheric nitrogen 

 in cooperation with the Bureau of Ordnance. Nitrate Division, of 

 the AVar Department. This has involved three lines of investigation : 

 (1) The synthetic, or so-called Haber process for the formation of 

 anmionia from hydrogen and nitrogen; (2) the preparation and use 

 of cyanamid for' fertilizer purposes; and (3) the utilization of the 

 silent discharge at liigh potential for the production of nitric acid. 

 The first of tliese investigations had advanced to such a stage that we 

 were able soon after war was declared to be of considerable service 

 to the War Department in investigating their special problems, the 

 Arlington laboratory being put at their disposal for such purposes. 

 In the year just closed work along all of the lines mentioned has been 

 extended. At the invitation of the Fixed Nitrogen Eesearch Labora- 

 tory, the men engaged in these investigations have been moved to the 

 American University to continue the work in cooperation with the 

 War Department. 



PHOSPHATES. 



Investigation of a method for the manufacture of phosphoric acid 

 by smelting the rock and recovering the acid from its gaseous state 

 has continued duiing the year. In the last report mention was made 

 of the results achieved with a specially designed furnace of small 

 size. This contrivance, itself the result of much experimental work, 

 is operated with fuel oil. and possesses the advantage over the electric 

 furnace first tried of being much cheaper to run. Experiments with 

 the new type of furnace are being carried out on a larger scale to 

 determine its commercial value. If the feasibility of this method 

 can be shown, its ultimate general adoption by the producers of acid 

 phosphate would seem assured, for the advantages — elimination of 

 waste in mining, production of a pure acid, and saving in the cost of 

 hauling an inunense tonnage of inert material — are manifestly too 

 great to.be ignored by those engaged in the business of phosphate 

 manufacture. 



POTASH. 



Investigations of the potash resources of the country have been 

 continued principally in connection with the recovery of the salt 

 from flue dust and its production from kelp. Many samples of the 

 dust from blast-furnace stacks and some additional samples from 



