Technological Changes and Transportation Development
Technological improvements over the centuries have yielded cheaper, faster, and better (less polluting, quieter, safer, more reliable) transportation services. Stories about this glorious history are usually in the language of vehicles, facilities, and propulsion. Wheeled wagons were in use at least 5,000 years ago, and about 2,000 years ago swiveling front axles aiding steering were developed. Roman roads helped tie the empire together, as roads did for empires in China and the Americas. Carts or sledges served where relatively good roads were not available. For years most folks walked along trails and horses, camels, and mules carried trading goods. About 200 years ago steam was harnessed for propulsion superseding sails and animals, and steam has been followed by otto cycle, diesel, and turbine engines. Fuel cells may arrive tomorrow.