Vol. X AUGUST 13,1917 No. 7 



JOURNAL OF 

 AGRICULTURAlv 



CONTKNXS 



Pag« 



Toughness of Bituminous Aggregates - - - - 319 

 CHARLES S. REEVE and RICHARD H. LEWIS 



Origin of Alkali - ------- 331 



ROBERT STEWART and WILLIAM PETERSON 



Effect of Paraffin on the Accumulation of Ammonia and 



Nitrates in the Soil - - - - - - - 355 



P. L. GAINEY 



Volatility of Organic Compounds as an Index of the Tox- 

 icity of their Vapors to Insects - - - - - 365 



WILLIAM MOORE 



PUBUSHED BY AUTHORITY OF THE SECRETARY OF AGRICULTURE, 



WITH THE COOPERATION OF THE ASSOCIATION OF AMERICAN 



AGRICULTURAL COLLEGES AND EXPERIMENT STATIONS 



WASHINOTON, D. C, 



WASHINGTON ; OOVEHNMENT PRJNTfNO OFFICE : IB)? 



