Global Worming
THE GREAT SCIENTIST Nikola Tesla was many things, but an advertising copywriter wasn’t one of them. When, therefore, as part of his ongoing research into high voltage phenomena, he placed a powerful electrode inside some glass filled with neon gas and switched it on he called the result – a glorious, touch-sensitive ball of miniature lightning – “an inert gas discharge tube”.
Perhaps not surprisingly, given it was lumbered with a name that evoked images of gastrointestinal end-play, Tesla’s invention, patented in 1894, remained a curiosity used only by electronics students and researchers for decades.
Almost a century later, in the 1980s, however, renamed as, variously, ‘the Tesla globe’ or ‘the plasma globe’, the device had become a hot seller in gift shops everywhere.
Thanks to an inverter that boosts a low-voltage DC power supply through an electronic oscillator and into a highvoltage transformer, the electrode at the centre of a Tesla globe’s sealed world sets off plasma filaments through an atmosphere comprising noble gases held at near-room temperature. The filaments extend to the glass insulator, producing gorgeous writhing electric discharge flows.
Apart from their appeal as household novelties – and their deployment as teaching aids in schools, universities and museums – Tesla globes aren’t actually useful for much. But that’s hardly the point. They are wonderful examples of the results of human inquiry – perhaps all the more so precisely because they can’t really be bent to the tasks of killing others or enriching oneself.
Ingenuity coupled with scientific research, many people believe, is only really commendable if the result can be used to solve a real-world problem.
It’s a debatable position. Inventions don’t always have to be practical. Sometimes they can just be beautiful.