In Britain, said device — typically attached to a vertical pole — is known as a traffic light, while in the US — usually adjoined to a horizontal overhanging beam — it is known in addition to traffic light as a stop light or, less formally, the light.
A yellow traffic light is a warning signal that lets you know that the red signal is about to be displayed. Hence, when you see the yellow light, you should start slowing down to come to a stop in anticipation of red light. The color yellow was used to caution drivers because it has a slightly shorter wavelength than red, but not as short as green.
Since yellow can be seen well at all times of the day, school zones, some traffic signs, and school buses continue to be painted yellow. They chose red as the color for stop, it is thought, because red has for centuries been used to indicate danger. According to the United States Access Board, more than , With only an elementary school education, Garrett Morgan began his career as a sewing-machine mechanic.
He went on to patent several inventions, including an improved sewing machine and traffic signal, a hair-straightening product, and a respiratory device that would later provide the blueprint for WWI gas masks. The inventor died on July 27, , in Cleveland, Ohio. His mother, Elizabeth Reed, was of Indian and African descent, and the daughter of a Baptist minister. His father, Sydney, a formerly enslaved person freed in , was the son of John Hunt Morgan, a Confederate colonel.
Morgan's mixed-race heritage would play a part in his business dealings as an adult. When Morgan was in his mid-teens, he moved to Cincinnati, Ohio, to look for work, and found it as a handyman to a wealthy landowner. Although he only completed an elementary school education, Morgan was able to pay for more lessons from a private tutor. But jobs at several sewing-machine factories were to soon capture his imagination and determine his future.
Learning the inner workings of the machines and how to fix them, Morgan obtained a patent for an improved sewing machine and opened his own repair business. Morgan's business was a success, and it enabled him to marry a Bavarian woman named Mary Anne Hassek, and establish himself in Cleveland. He and his wife would have three sons during their marriage.
Following the momentum of his business success, Morgan's patented sewing machine would soon pave the way to his financial freedom, albeit in a rather unorthodox way: In , Morgan was working with sewing machines in his newly opened tailoring shop — a business he had opened with wife Mary, who had experience as a seamstress — when he encountered woolen fabric that had been scorched by a sewing-machine needle.
It was a common problem at the time since sewing-machine needles ran at such high speeds. The patent was granted on November 20, Morgan later had the technology patented in Great Britain and Canada. He also invented a zigzag stitching attachment for manually operated sewing machine. In , Morgan made national news for using a gas mask he had invented in , used to rescue several men trapped during an explosion in an underground tunnel beneath Lake Erie.
The Morgan gas mask was later refined for use by U. Army during World War I in Morgan, the child of two formerly enslaved people, was born in Kentucky in When he was just 14 years old, he moved north to Ohio to look for a job. First he worked as a handyman in Cincinnati; next he moved to Cleveland, where he worked as a sewing-machine repairman. In , he opened his own repair shop, and in he added a garment shop to his operation. The business was an enormous success, and by Morgan had made enough money to start a newspaper, the Cleveland Call , which became one of the most important Black newspapers in the nation.
There were manually operated traffic signals where major streets crossed one another, but they were not all that effective: Because they switched back and forth between Stop and Go with no interval in between, drivers had no time to react when the command changed. This led to many collisions between vehicles that both had the right of way when they entered the intersection.
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