At the beginning of the twentieth c

At the beginning of the twentieth century , traffic in big cittes such as new york and london became busy and
hectic . carriages , wagons, horses,and then they were joined by the newest toy of the wealthy , the antomobiles.
In those days, crossing a street used to be a real challenge for pedestrians. there were on rules for dievers. the new york police department had to create a special squad to hadle traffic . police officers stood at intersections and
tried to direct the traffic , but evry often they were run over by vehicles . by 1912 , new york city had 38,000
motor vehicles. something had to be done about all the traffic on the streets !
In 1916 ,the first traffic tower was put up in new york , at the intersection of fifth Avevue and 42 nd street.
A traffice officer controlled three 500 - watt lamps. they measured 40 centimeters in diameter ,and they were
red , amber meant traffic in all directions had to stop , amber sstopped only east - west traffic, and green
stopped only north - south traffic. this was very confusing , so in 1924 the city adopted the ststem used in
railroads : red of stop , green of go , and yellow for slow . this ststem became standard all over the world.

the first automatic traffic lights were installed in wolverhampton , england, in 1927. today computers
control traffic lights, and road conditions is a power outage . the result is often confusion on the streets
because the traffic lights don't work.