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Garth Rattray | Our ‘disappearing’ traffic lights

Published:Sunday | September 3, 2017 | 12:00 AM

The sole purpose of traffic signals is to prevent damage, injury and death from accidents and crashes. The very first traffic signal was invented by a British railroad signalling engineer, John Peake Knight. It was a manually controlled, gas-operated device, used to regulate the flow of horse-drawn carriages and to allow pedestrians to cross the road safely.

Knight's traffic signal was installed outside the Houses of Parliament (in London) in 1868. Unfortunately, a gas leak caused an explosion that badly injured the policeman who operated the device. That nixed the system entirely.

The advent of the internal combustion engine brought with it a rapid increase in automobile traffic. In 1912, Lester Farnsworth Wire, an American policeman, thought up the idea of using electricity to operate the red-green traffic light. It was said that he dipped the bulbs in red or green paint and connected the system to the nearby electricity supply for tramlines. It was manually operated by the on-duty policeman. At some point, the device included a buzzer that sounded to indicate an imminent colour change.

In 1920, another American policeman, William L. Potts, invented the three-coloured, four-way traffic light - it was never patented. The middle amber replaced the buzzer to warn of an imminent colour change.

However, in 1923, African-American inventor, businessman and author Garrett Morgan of Cleveland, Ohio, patented his version, an automated, electric traffic light. It had three arms and sat atop a pole. He was inspired to design the signal after witnessing a horrible crash, at an intersection, between an automobile and a horse-drawn carriage.


Smart lights


William Pott's invention served as the basis for the three-coloured, light-bulb design that we see today - automatically operated coloured lights, typically red, amber, and green, for controlling traffic at road junctions, pedestrian crossings, and roundabouts. Nowadays, some devices can sense and adjust to the presence and flow of traffic. Some can also be programmed for peak traffic times and even be controlled centrally.

The simplicity and efficacy of the traffic light can ensure safety - if people obey them.

- A steady red light means stop - do not go. The same applies for a steady red arrow.

- A steady yellow light means that the traffic light will turn red soon. You must stop safely or proceed carefully if you are already in the intersection. Some years ago, a steady yellow would come on after the red but before the green and was used to indicate that the green would soon appear. However, many impatient drivers false-started and crashes occurred.

- Steady green means go - if it is safe to do so. The same applies for a steady green arrow.

- Flashing traffic lights mean use extreme caution. Drivers should stop to make certain that they may proceed slowly and carefully.

- Malfunctioning lights should be treated as four-way stop junctions, with all sides stopping and pausing until the way is clear.

As I predicted, in today's Jamaica, it's as if our traffic lights are disappearing. It is not uncommon to see road users driving through red lights, in broad daylight. The main offenders are motorcyclists, taxicabs and minibuses. However, others commit the same infraction with such regularity that I wish that I had convex-lensed eyes to the sides of my head and drove a heavily armoured battle tank.

I notice that it has become a nasty habit for drivers to turn on red signals. No Jamaican law permits this without a green arrow or a slip road.

But nowadays, some drivers are doing so as if it's their right of way. Some even force approaching drivers (with the green light) to stop and wait on them. The most commonly abused intersections are Half-Way Tree Road on to Ruthven Road and Waterloo Road on to South Avenue.

Recently, I was proceeding west on Waterloo Road and the light changed to red as I was about to turn left on to South Avenue. I stopped, but the din of blaring horns behind me was almost deafening. The way that they carried on, one would have thought that I was dancing naked on the roof of the car! A long line of screw-faced, gawking, ignorant imbeciles managed to squeeze by me and turned boldly through the red. "Where's a cop when you need one?" I thought, as I contemplated our dismal future.

- Garth A. Rattray is a medical doctor with a family practice. Email feedback to and