A fondness for Ireland led Syracuse, New York to invert the common design for these devices well into the 1960s.  
Physician John A. Harriss personally financed the first permanent one of these things in New York City.  Hans Monderman successfully experimented with removing these things.  A fondness for Ireland led Syracuse, New York to invert the common design for these devices well into the 1960s.  Salt Lake City police officer Lester F. Wire may have invented these things, with a prototype adapted from a birdhouse.  The architect Joseph H. Freedlander designed cast-bronze examples for the (*) Fifth Avenue Association in New York.  Unlike modern examples of these things, the prototype of one designed by Cleveland hair-straightening entrepreneur Garrett Morgan had words printed on it; Morgan is often celebrated during Black History Month.  In the 1920s, these devices made redundant some fifty-five hundred New York City police officers.  For 10 points, name these safety devices which automatically regulate traffic flow at intersections.
Physician John A. Harriss personally financed the first permanent one of these things in New York City.  
stop lights [or traffic signals; or traffic lights] 