When a president of the United States takes up so much of his annual message with transportation and the relationship which the different forms bear to each other, when he argues for harmony between them and between them and their employees, there is certainly reason for study and legislation which will bring about just and adequate methods of administration, operation and regulation. SELECTED REFERENCES Agricultural Inquiry, Report of Joint Commission on, Part III deals with Transportation, Washington, D. C., 1922. ALDEN, H. W., “Automotive Obligations Toward Highway Development,” _Journal of the Society of Automotive Engineers_, Vol. VIII, pp. 161-162, 426-432. _Automotive Industries._--“Automobile Service Stations,” Vol. XLVII, pp. 174-175; “Automobiles in Postal Service,” 178-179; “Cost of Operation of Bus Lines,” 482-483; “Motor Trucks on the Farm,” 315; “Railroad Officials Recognize Truck as Transportation Ally,” Vol. XLIII, 1201-1203. BAKER, C. W., “Relative Economy of Truck and Railway,” _Engineering News-Record_, Vol. LXXXIII, pp. 52-67. BASSETT, W. R., “Avoiding Industrial Traffic,” _Industrial Management_, Vol. XLI, pp. 342-346. BLANCHARD, A. H., “Traffic and Transportation,” _Canadian Engineer_, Vol. XL, pp. 129-131. BLUM, H., “Transportation of Bulk Freight,” _Kali_, Halle, Germany. _Bus Transportation._--“Baltimore Service,” Vol. I, p. 484; “Motor Buses,” 479-80; “Bus and Electric Railways as Essentials in Transportation,” by G. A. Green, 293-295; “Battle of the Bus and the Street Car,” by F. H. Warren, 85-88; “New Englanders Hold Meeting to Study Motor Bus and Trackless Trolley,” 124-129, 191-193; “Railway Men Discuss the Bus and its Relation to Rail Transportation,” 195-196. DAVIS, F. W., “Motor Truck Transportation,” _Engineering News-Record_, Vol. LXXXV, pp. 1194-1195. DONNELLY, WILLIAM T., “Comparison of Cargo Transportation,” _Marine Engineering_, Vol. XXV, pp. 899-903. _Engineering._--“Bringing the Food to the Table,” Vol. VI, pp. 387-391. _Electric Railway Journal._--“Report of Committee on Trackless Trolley Transportation to the American Electric Railway Association,” Vol. LX, pp. 576-577; “Freight and Motor Truck Competition,” Vol. LVI, pp. 157-160. Development of the Automobile: HISCOCK, GARDNER D., “Horseless Vehicles,” Norman W. Henley & Co., New York, 1901. HOMANS, JAMES E., “Self-Propelled Vehicles,” Theo. Audel & Company, New York, 1902. “History of Automobile Carriages,” reprinted from _La Nature_ by the Scientific American, Vol. LXXII, p. 389, June 22, 1895.