Garrett Morgan - Traffic Signal

Traffic Signal

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. Between 1913 and 1921, a number of versions of traffic signaling devices, both mechanical and automated, were patented by various inventors. Of these, only a few saw production or implementation on public roads. Morgan's device, first patented in 1923, was a hand-cranked, manually operated mechanical semaphore signal. His device had two key safety features: having an intermediate "all stop" signal state to give moving traffic time to stop before signaling cross traffic to proceed, and having a "half mast" position to indicate general caution at times when the device operator was not present.

There is no evidence to support the claim that Morgan's traffic signal was ever put into service. Despite claims on various websites as well as in print that Morgan's invention was used "throughout North America", the absence of his signal in 1920s photographs and news articles suggests that it was not installed in large numbers, if at all. Notably, it did not merit a single mention in the book-length historical study by Gordon M. Sessions, which covers a wide variety of devices in tracing the development of traffic-control devices throughout history.

Many of these sources also claim that the patent rights for Morgan's designs were sold at about that time to General Electric (GE) for $40,000. However, no record of this transaction appears either in the U.S. patent assignment records at the National Archives, the GE historical business records at the Schenectady Museum in New York, or in Morgan's own legal and business papers at the Western Reserve Historical Society in Cleveland. Advertisements and photos from the 1920s indicate that GE's early traffic signal products were of the more modern electric variety, not manually operated semaphores. Several GE patent acquisitions from the early-to-mid 1920s show that the company was investing heavily in solid-state electronic circuitry and automated traffic signaling devices during that time. By the end of 1926, GE had begun experimenting with traffic-controlled systems (as opposed to timer-controlled devices); it is highly implausible that GE would consider investing $40,000 (over $500,000 USD inflation-adjusted to 2011) in a manual, crank-driven signaling device during an era when the company was researching, developing and producing solid-state analog circuitry and actively implementing these technologies into their signals.