The French are reported to have considered a center-rail system 

 for battlefield railways during World War I. As late as 1920, it 

 was claimed that such roads could be quickly and cheaply built 

 and would do good service in hauling supplies and heavy artillery 

 over the rough terrain of the front lines. '■" The similarity of these 

 claims to those expressed for the center-rail system by Sellers should 

 be readily apparent to the reader. 



'3' "Traction on Heavy Gradients by Means of Auxiliary Adhesion," Bulletin oj 

 the International Railway Association, Brussels (January-February-March 1920), 

 vol. 1 1, pp. 272-284. 



90 



