John Peake Knight was a railway man who worked on the lines in England. John was also the guy who designed the first street traffic light in the world.
It all started out as a local problem. London England had seen 1102 pedestrians killed and 1334 injured during the single year of 1866. Horse and carriage traffic had become very heavy in the city and simply crossing the street was perilous due to the fact there had been no regulations put into place yet to order traffic. The city’s streets were largely a free-for-all.
By 1868, John Peake Knight developed a system for regulating road traffic at the busiest intersections, operated by a police officer and following the basics of the mechanical semaphore communications used on the railway. So…with what I can piece together from the descriptions…you had a cop who was activating levers on a pole to raise and lower different mechanical arms which signalled the stop and go instructions telling drivers what they should be doing. Then at night, he used green and red gas-powered lamps to do the job in the dark.
The theory seemed to work until there was a gas leak one night and one of the signal lamps exploded, seriously injuring the officer who had been left on overnight traffic duty. Poor guy. The night shift is always when the weird stuff happens. After the explosion, Londoners got a bit twitchy about the whole new-fangled traffic light thing (I’m sure that speaks for the constabulary as well) and the entire experiment was scrapped. London went on to use traffic cops who stood in the very middle of popular intersections and waved their arms around to direct the flow of horses, carriages, pedestrians, bikes, and eventually vehicles, until 1929 when the electric version of what John had invented, showed up.
Although several other versions were being experimented with in various places throughout the early years of the 20th century, the 3-light electric traffic light was finally invented by an innovative policeman from Detroit in 1920. Since he worked for the city, he wasn’t allowed to hold a private patent on anything he invented for public safety, so as his working 3-colour traffic light went viral and changed the course of vehicular history, he continued to live out his life on a policeman’s salary. Hopefully he got an extra big Christmas Hamper that year from the department.
The 3-light traffic signal found its way to Canada in 1925. Guess where. In Hamilton, the sleeper competitor for almost everything with Canadian roots. At that time, the yellow light was accompanied by the ringing of a bell in order to notify drivers that the light was about to change to red and that they would be expected to stop. However, the neighbours around that first traffic-light-controlled intersection of King and Main Streets in Hamilton were almost driven mad from the constant ringing so the city had to do away with the audible alert portion and just forge ahead with the coloured lights giving drivers their instructions. It’s kind of amazing that the whole electric traffic signal thing ever got any traction from that first early experiment because the intersection of King and Main was always going to be a nightmare to control. Main Street comes in at an angle and the drivers really couldn’t figure out which traffic light was supposed to be theirs. Luckily, the City Fathers tried putting in another experimental set at the intersection of Cannon and James Streets and that’s when it really caught on. The successful use of traffic lights would spread to all of the other cities in Canada that had enough traffic to regulate.
On March 5 1928, at 8am, the initial 12 sets of traffic lights were turned on for the first time in Ottawa. I would love to be able to beam back in time to watch that event! Police were gathered at most of the corners to keep the chaos to a minimum and check that the timing of the new lights would work for the streetcars unloading and loading. The police presence drew onlookers to the corners and the crowds grew as they watched the spectacle of the New Traffic Lights as it unfolded. Drivers of both automobiles and streetcars, most of them not familiar with the installation of the new traffic lights, would just blow right through the intersections like normal–no doubt to the cheers or shouts of the spectators! They would eventually catch on and the system turned out to be such a success that after a few months of operation, Ottawa decided to run them 7 days a week, rather than just Monday through Saturday. Imagine!!
Those first traffic lights were run on 60 watt incandescent light bulbs. LED light bulbs are the chosen lighting option these days because they are low wattage and still operate on a reduced brightness if they are about to burn out, thereby giving a warning to change them. They are between 8” and 12” across, depending on the unit they are used in. The light from the bulb shines through two lenses and foil tape is used to contain/direct the beam so that only those whom the light affects, are able to fully see its colour.
The former incandescent and halogen bulbs generated a bit of heat during their normal running operation, which kept their visors slightly warm. This small amount of heat would automatically melt any snow that might build up on top of the visor and obscure the light above. Since LEDs do not give off any heat, LED traffic lights in snowy climates are fitted with a low wattage heating element to eradicate the problem. I wonder if running heaters to augment the shortcomings of the energy-saving lightbulbs, chose to replace the wattage-hungry self-warming versions, pays off in the long run.
Nevermind.
I hope that John Peake Knight would be gratified by our very modern adaptation of his original traffic light idea. I think he would be proud that of the 96 traffic deaths in London England last year, they estimate that only 45 to 50 of them would have happened at intersections or within 20 metres of an intersection. And, that none of the injuries reported had anything to do with exploding traffic lights. We’ve come a long way.