THE CONQUEST OF TIME AND SPACE 



motive that operated on the streets of London and the 

 public highways, hauling a wagonload of people. But 

 the unevenness of the roads proved disastrous to his 

 engine, and as it could make no better time than a 

 slow horse, it was soon abandoned. But Trevi thick 

 had learned from this failure that a good roadbed was 

 quite as essential to the success of a locomotive as the 

 machine itself, and two years later he produced what 

 is usually regarded as the first railway locomotive. This 

 was built for the Merthyr-Tydvil Railway in South Wales, 

 and on several occasions hauled loads of ten tons of iron 

 at a fair rate of speed. It was not considered a success 

 financially, however, and was finally abandoned. 



At this time a curious belief had become current 

 among the inventors to the effect that if a smooth-sur- 

 face rail and a smooth-surface wheel were used, there 

 would not be sufficient friction between the two to 

 make it possible to haul loads, or more than barely 

 move the locomotive itself. Learned mathematicians 

 proved conclusively on paper by endless hair-splitting 

 calculations that the thing was impossible, — that any 

 locomotive strong enough to propel itself along a 

 smooth iron rail would be heavy enough to break the 

 strongest rail, and smash the roadbed. In the face of 

 these arguments the idea of smooth rails and smooth 

 wheels was abandoned for the time. Trevithick him- 

 self was convinced, and turned his attention to the per- 

 fecting of an engine with toothed drive-wheels running 

 on a track with rack-rails. But this engine soon jolted 

 itself and its track into the junk-heap without doing 

 anything to solve the problem of locomotion. 



[122] 



