TABLE OF CONTENTS. 



Page. 



Part 1. Agents of power 9 



Mechanical elements 9 



Natural forces 11 



Steam engines 12 



Air and internal combustion engines 31 



Part 2. Application of power to transportation 52 



Self-propelled road vehicles 52 



Railway locomotives 63 



Part 3. Railway permanent way 89 



Part 4. Early history of land transportation 100 



5 



