Garrett A. Morgan
and the Traffic Light
When would 10th grader Garrett A. Morgan ever use his knowledge of engineering processes in real life?
When he improved and patented the modern day traffic light at the age of 37.
The first American-made automobiles were introduced to consumers just before the turn of the 20th century, and pedestrians, bicycles, animal-drawn wagons and motor vehicles all had to share the same roads. To deal with the growing problem of traffic accidents, a number of versions of traffic signaling devices began to be developed, starting around 1913.

Garrett Morgan, the son of a freed slaved with a sixth grade education, witnessed a serious accident at an intersection, and soon after he filed a patent for traffic control device in 1922. Morgan patented the three position traffic signal on November 20, 1923 at the age of 46. His invention was an improvement on the two position lights that just had stop and go. The existing lights were not very effective. They were manual lights with no warning or set interval. This meant drivers often didn't have time to react causing collisions. Morgan's idea was to have a warning position so oncoming traffic would know the light was about to change and give them time to react.

Patent number 1475074 for a t-shaped pole with three settings that could be set at half-mast at night during low to no traffic. It was a shaped pole unit with 3 positions. Stop, go and all directional stop so pedestrians can safely cross. It was a hand cranked semaphore device and was used throughout North America.



Bibliography

Asante, Molefi Kete (2002), 100 Greatest African Americans: A Biographical Encyclopedia. Amherst, New York: Prometheus Books.

Bellis, Mary (2016) The Garrett A. Morgan Traffic Light. Retrieved from http://inventors.about.com/od/photogallery/ss/Garrett_Morgan.htm#step5
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This material is based upon work supported by the U.S. Department of Transportation under Cooperative Agreement No. DTFH6114H00004. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the Author(s) and do not necessarily reflect the view of the U.S. Department of Transportation.
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