Abstract :
A FLEXIBLE progressive traffic signal system usually makes it possible to time signals so that traffic may move east and west, as well as north and south, at predetermined uniform speeds without being obstructed by a “stop” signal after once having passed a “go” signal. The planning of such a system is a matter that requires most intelligent study and one which yields results well worth the effort. Traffic-actuated equipment seldom can be justified over pre-timed equipment, as in a great majority of congested districts the coordination of the movement of traffic through the entire district is of incomparably greater importance than the most efficient movement of traffic at any few intersections taken by themselves.
