Automotive transportation may be considered to include all conveyance from one place to another by means of motor vehicles. A motor vehicle is one which carries within itself the source of mechanical power which propels it providing that source be not muscular. This definition would include the tractor, the road roller, the torpedo, and the locomotive, which are ordinarily excluded. For the purposes of this discussion an automobile or motor car may be considered as a self-propelled vehicle which transports a burden other than itself as a weight upon its own wheels. This will exclude the tractor and the locomotive, which though self-propelled, are intended to draw other vehicles rather than to carry the load; also the road roller and the torpedo, which have no burden to transport other than their own weights. Some definitions would confine a motor vehicle to one designed to move on common roads or highways. However, motor cars are now being used on railroad tracks; they are entitled to and should be allowed the use of the name. The automobile may have as the source of power internal-combustion engines using such fuel as gasoline, kerosene, benzol, and alcohol; it may use steam generated by these fuels; or an electric storage battery charged by sources outside the engine may furnish the propelling force. The load transported will either be passenger or freight. Passenger traffic may be classified as business or pleasure. If a vehicle is used mostly for business, first cost and economy of operation may play a more important part in the purchase of the car than if used for pleasure, in which case appearance and luxurious appointments may be the deciding factor. [Illustration: THE EVOLUTION OF THE STEAM AUTOMOBILE 1. The Cugnot Steam Carriage--1770. 2. The Trevithick & Vivian Steam Carriage--1801. 3. The Gurney Steam Carriage--1827. 4. The Church Automobile Carriage (Steam)--1833. 5. Gaillardit’s Steam Carriage--1894. (Courtesy of the _Scientific American_.)]