Light, Sound and Waves

Twain’s ‘unspeakable and pressing necessity’

Stories from Physics for 11-14 14-16 IOP RESOURCES

Nikola Tesla encouraged Mark Twain to stand on an electrotherapy device he had invented consisting of a platform supported by elastic cushions that was vibrated with compressed air. Tesla proposed that the device would encourage regular bowel movements and reported that, during a trial:

“Suddenly, Twain felt an unspeakable and pressing necessity which had to be promptly satisfied.”


is a special case of Oscillation
is exhibited by Resonating System
can be analysed using the quantity Resonant Frequency Natural Frequency
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