230 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



INFORMATION. 



The section of soil information and advice has answered many in- 

 quiries and o-iven much advice locally to persons asking it during the 

 year. The demand for advice by persons desiring to plant gardens 

 has been very great. This section has done much work in preparing 

 an exhibit of the work of the bureau to be shown at a number of the 

 more important agricultural fairs. 



CHEMICAL INVESTIGATIONS. 



The work carried on in the Division of Chemical Investigations 

 during the fiscal year 1918 was along the same general lines as dur- 

 ing the year preceding. 



The number of miscellaneous samples submitted by other bureaus 

 and by individuals for analysis continued to be large. For the most 

 part these were samples of limestone, marl, or other lime-contain- 

 ing material submitted for an opinion regarding their suitability for 

 liming purposes and samples of soil the lime requirement of which 

 it was desired to know. 



The analyses of carefully selected samples of American virgin 

 soils begun last year has been carried on, and 28 samples involving 

 336 determinations have been completed. About 20 samples remain 

 to be analyzed, and the work when completed will furnish informa- 

 tion regarding the composition of American virgin soils not here- 

 tofore available. 



Such research work as it has been possible to carry on has been 

 confined for the most part to problems connected with the liming of 

 soils. The work on the forms of lime in soils has been continued, 

 and a beginning made on a study of diffusion of liming material 

 through the soil. Progress has also been made on the study of the 

 solubility of liming material as affected by impurities. 



In connection with the work on liming, a Farmers' Bulletin (No. 

 921, " The Principles of the Liming of Soils ") has been published. 



FERTILIZER RESOURCES INVESTIGATIONS. 



The fertilizer situation, owing to war demands, the decrease of im- 

 portations, the congestion of traffic, and the unsettled labor condi- 

 tions, has continued difficult with prices maintained at a high level. 



The work of the division with reference to the fixation of atmos- 

 pheric nitrogen has been carried on actively in cooperation with the 

 Bureau of Ordnance of the War Department. The Haber installa- 

 tion for the production of synthetic ammonia was completed during 

 the year and has been operated successfully. The War Departrnent 

 has recently requested the use of this installation for the purpose of 

 testing various catalysts, and this work is being carried forward now 

 by this division assisted by experts detailed from the Bureau of Ord- 

 nance. The mechanical difficulties connected with this process have 

 been overcome completely and the possibility of producing synthetic 

 ammonia by this method at a reasonable cost has been demonstrated. 



In connection with the nitrogen-fixation work it became necessary 

 to study the problem of oxidizing ammonia for the production of 

 nitric acids and nitrates. The ordinary method of oxidation involves 



