Train

It will be perceived that the air-brake provision deals with running a train, while the other requirements relate to hauling or using a car. In one a train is the unit and in the other a car. As the context shows, a train in the sense intended consists of an engine and cars which have been assembled and coupled together for a run or trip along the road. When a train is thus made up and is proceeding on its journey it is within the operation of the air-brake provision. But it is otherwise with the various movements in railroad yards whereby cars are assembled and coupled into outgoing trains, and whereby incoming trains which have completed their run are broken up. These are not train movements, but mere switching operations.