All of us have learned since secondary school that the reason we use red in the traffic lights for "Stop" is because it travels the furthest without dispersion. According to wikipedia which cites about.com, the first red-green traffic light was installed in 1912. Now, Dr. Maxwell discovered his three laws between 1861 and 1862. My googling threw up this link (which does not cite sources) that the red-green for stop-go was already standard practice in industrial controls by the 19th/20th century, which probably explains why and how Lester Wire came up with the red/green for his first traffic light installation.
So, was the choice of red-green for
traffic lights industrial controls just a happy coincidence or did someone research them before coming up with the colors? If so (with research), why not have red and blue for traffic lights?