314 . REPORT— 1902, 



The Besistance of Road Vehicles to Traction.- — JReportofthe Committee, 

 consisting of Sir Alexander Binnie (Chairman), Professor H, S. 

 Hele-Shaw (Secretary), Mr. T. Aitken, Mr. T. 0. Aveling 

 (Treasurer), Professor T. Hudson Beare, Mr. W. Worby 

 Beaumont, Mr. J. Broavn, Colonel R. E. Crompton, Sir D. 

 Salomons, Mr. A. 11. Sennett, Sir J. I. Thornycroft, and Mr. 

 W. H. Wheeler. Associated with them were Mr. A. Mallock 

 and Mr. E. Shrapnell Smith. (Braivn up, at the request of the 

 Committee, hi/ the Secretary, assisted by Mr. J. F. Gill, B.Se.) 



Plates III.-VII. 

 Contents. 



PAGE 



T Preface 314 



II. The WorJis of Co'rrhe and Manes (1832) 314 



in. The IVork of CorioUs (1835) 315 



IV. Expei'imeiits and Gmclusions of General Morin (l837-i2). . , , 316 



V". The Researches of M. BHpuit 323 



N\. Theoretical Incestiqation by Edmund Leahy, C.E. (IM7) . . , . 326 



Vll. The WorhofM. Charii-Marsaines 329 



YIII. Experiments by A. MicheUn (1896) 330 



IX. Extract from the lleport of Profcasor W. C. Unwin, F.R.S., on the 

 Trials of Self-moving Vehicles at Birmingham made before the Royal 



Agrlcukural Society (1897) 336 



X. Experiments by Professor H. S. Hele-Sluiw, F.R.S. (1897) . . .337 



XI. Investigations of Professor Ira O. Baker (1902) 338 



XII. Summary of the Opinions of Various Writers on the Relation hetween 

 Tractive Effort and the Various Independent Elements of Road 



Resistance 343 



XIII. Description and Drawings of the JVem Dynamometer made for the 



British Association Committee to carry on the Researches . , . 34.5 



XIV. Nature ayid Scope of the Experl'innts by the Committee .... 346 

 XV. The Work of the Com7nlttee presented at the Meeting .... 347 



I. Preface. 



The first ten sections of this Report give a summary of the work done 

 on road resistance from the earliest time for which records are available. 

 It is quite possible that the work of some investigators may have been 

 overlooked, but at the same time the chief results which have hitherto 

 been made known are presented, for the first time, in a concise form. 

 The work of most of the French observers has been drawn to a great 

 extent from A. Debauve's ' Manuel de I'ing^nieur des ponts et chauss^es.' 



It has not been possible to carry out during the present year in a 

 sufficiently complete manner the experiments with the British Association 

 apparatus in order to be able to compare the results obtained with the 

 formula; and laws which the summary gives, but it is hoped that by 

 another year the work will have been sufficiently advanced to enable this 

 to be done. 



II. Corrize and Manes (1832). 



MM. Corr^ze and Manes treated the subject from both theoretical and 

 practical standpoints, and the conclusions they arrived at fully confirmed 

 a series of experiments made by a commission of engineers in 181G, 



