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Taking On Traffic: A Closer Look at the Signals

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It might seem obvious that traffic control development paralleled the growing use of automobiles. Especially after World War I, an increase in traffic created a need for more systematic signals. The first traffic light in the United States was installed in 1914 in Cleveland and the first interconnected signal system was introduced in Salt Lake City in 1917. By the late 1920s, most U.S. cities saw the implementation of pre-timed systems, the early model for what we see today.

Actually, traffic lights predated the automobile era. In December of 1868, the world’s first traffic lights were installed in London, close to Westminster Bridge. Policemen had to stand next to the signals to operate them. However, about a month into the new traffic light project, a leaky gas main caused one of the traffic lights to explode in the face of the operating policeman! It would be another 40 years before traffic lights reappeared around the world.

I came across the photo below of quite the chaotic Detroit traffic scene, and it took a moment before I noticed how unusual the traffic system looked. If you zoom in for a closer look, you can spot a sort of booth with lights fixed atop, and the guard using a megaphone to direct traffic himself!

[Traffic, Detroit, Mich.] Photo by Detroit Publishing Company, between 1915 and 1925. //hdl.loc.gov/loc.pnp/det.4a27913
Traffic, Detroit, Mich. Photo by Detroit Publishing Company, between 1915 and 1925. //hdl.loc.gov/loc.pnp/det.4a27913
Close up of [Traffic, Detroit, Mich.] Photo by Detroit Publishing Company, between 1915 and 1925. //hdl.loc.gov/loc.pnp/det.4a27913
Detail of Traffic, Detroit, Mich. Photo by Detroit Publishing Company, between 1915 and 1925. //hdl.loc.gov/loc.pnp/det.4a27913
And from another angle, a similar raised booth in Detroit traffic:

[Crowded street, Detroit, Mich.] Photo by Detroit Publishing Company, between 1915 and 1925. //hdl.loc.gov/loc.pnp/det.4a27907
Crowded street, Detroit, Mich. Photo by Detroit Publishing Company, between 1915 and 1925. //hdl.loc.gov/loc.pnp/det.4a27907

When reading histories of traffic signals in the United States, I noticed Detroit was a particularly difficult city to navigate, and it seemed to be the breeding ground for major traffic signal developments. Today’s tri-tone signals developed when the yellow light between red and green was added by a Detroit police officer named William Potts in 1917. The yellow color was to alert drivers and pedestrians of the oncoming change. In 1920, Potts also built the first four-direction light. A few years later in 1928, the 12 bulb system was created, with red now always on top.

Traffic Director Eldridge inspecting new lights 1/5/26. Photo from the National Photo Company, January 5 , 1926. //hdl.loc.gov/loc.pnp/npcc.15386
Traffic Director Eldridge inspecting new lights 1/5/26. Photo from the National Photo Company, January 5, 1926. //hdl.loc.gov/loc.pnp/npcc.15386

Taking a step back from the light systems and looking at human traffic controllers- I thought the image below was fascinating, not only because of the Stop-Go sign and the umbrella attached, but the mirror that allows the guard to also watch his back!

[Traffic officer, Washington, D.C.] Photo by Harris & Ewing, between 1915 and 1923. //hdl.loc.gov/loc.pnp/hec.29851
Traffic officer, Washington, D.C. Photo by Harris & Ewing, between 1915 and 1923. //hdl.loc.gov/loc.pnp/hec.29851
Leola N. King, wife of Cap. E.H. King, med. capt. Photo from the National Photo Company, between 1918 and 1920. //hdl.loc.gov/loc.pnp/npcc.00299
Leola N. King, wife of Cap. E.H. King, med. capt. Photo from the National Photo Company, between 1918 and 1920. //hdl.loc.gov/loc.pnp/npcc.00299

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Comments (2)

  1. A very valuable inspirational story of just how significant positive innovation can be and that it is many times a long process. This goes for navigating streets or life.

  2. When researching a photo of a ca. 1925 “traffic tower” at 4th Avenue + Pike Streets in Seattle, I took a look at the street grid. Turns out it’s a complicated intersection, with Westlake intersecting at that point as well. Having a complicated intersection would certainly call for more traffic direction. Enjoyed the column.

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