alexanderrogge
Al Jazeera - A brief history of the traffic light and why we need a new colour:A brief history of the traffic light and why we need...#TrafficSignal #TrafficLight #TrafficSafety #Throughput #Efficiency #ParliamentSquare #London #WilliamPott #Detroit #GasLight #GarrettMorgan #SemaphoreSignalling #Semaphore #History #TransportationEngineering #Engineering #Transportation