And then there was light

Valsala R tracks the origin of the light bulb and howBengaluru features prominently in this tale

How many times a day do we all turn the lights on but… think nothing of it? If you do stop to think about it, what a little miracle it is!

Ask your grandparents and they will most likely have tales to tell you of how life was without the marvel of electric light. They would have studied, played, cooked and talked by the light of a noisy petromax or a hurricane lamp.

So who do you think was responsible for lighting up our lives? If you said Thomas Alva Edison, you wouldn’t be wrong but that isn’t quite all that there is to it. You see, almost 75 years before Edison turned on the lights of the world, several people had toyed with the idea. Humphrey Davy in England was experimenting with electricity and he invented an electric battery. Add wires and a bit of carbon to the battery and lo and behold, a bright arc of light was produced between the two carbon rods. The Electric Arc of light just didn’t last long at all — it simply burnt out.

Around 38 years later, another British scientist used a platinum filament in a vacuum tube through which he passed electricity. Since the vacuum chamber protected the filament from other gas molecules and since platinum itself has a high melting point, this was indeed an efficient design. But platinum? Can you imagine how much we’d be paying for each of those bulbs? So the hunt for the perfect light bulb went on.

Another 20 years went by before Joseph Swan had the clever idea of using carbonised paper filaments in an air-free bulb. Swan had made a bulb that solved the cost problem. But the vacuum wasn’t quite good enough and so the filament burnt up. Swan continued to work on it. Better vacuum pumps were beginning to be available and there seemed to be hope.

Another 14 years passed before a couple of young Canadian electricians, Woodward and Evans, experimenting with different sizes and shapes of carbon rods and glass cylinders with two electrodes that were filled with nitrogen, hit upon the ‘almost’ perfect light bulb. ‘So now what was wrong?’ you may ask. Well, they just didn’t know how to make it a commercial success. So guess who they sold their patent to? Thomas Edison.

By this time, Edison himself had begun working on ways and means to create a practical lamp. He realised that effectiveness and cost had both to play an important role for the venture to be a commercial success. He tried several metal filaments. Indeed his 1879 patent describes a lamp with filaments using “cotton and linen thread, wood splints, papers coiled in various ways”. But then, he and his team discovered that carbonised bamboo filaments could last over 1200 hours. The Edison Electric Light Company began the commercial manufacture of light bulbs in 1880.

There’s a Bengalurean postscript to this story. In the early years of the 20th century, like most places all over the world, Bengaluru had its own team of lamplighters. Men, who would go around the city, trim the wicks of street lamps, fill them with kerosene and light them. A British company was conducting mining activities in KGF and they needed power.

Asia’s first hydroelectric project had been set up at Shivanasamudra, so power was transmitted 150 km from there to the KGF mines. The lines passed right through Bengaluru. Once the hydroelectric project was producing more electricity than was needed by the mine it only took some innovative thinking to use the excess power to light up our city. Look for the 117-year-old first electric street lamp near KR Market.

(The author is a writer and a soft-skills and communications trainer.)

Watch the latest DH Videos here: