Nikola Tesla’s Cat: The Unexpected Inspiration Behind the AC Power System

A black cat, like this one, inspired Tesla's fascination with electricity.

Nikola Tesla was famous for inventing many things. But the role his cat played in his most famous contribution to science — creating the alternating-current (AC) electric system, still the main electrical system in the world today — is not well known. Here's how it happened:

A black cat named Macak was Tesla's favorite childhood companion. Decades later, in a 1939 letter to a 12-year-old, Tesla recalled how this cat shocked him into a lifelong fascination with electricity. Part-Time Genius co-host Will Pearson read some of the letter on an episode about cats. "In the dusk of the evening as I stroked Macak's back, I saw a miracle which made me speechless with amazement. Macak's back was a sheet of light, and my hand produced a shower of crackling sparks loud enough to be heard all over the house ... My mother seemed charmed — 'Stop playing with the cat,' she said. 'He might start a fire.' But I was thinking abstractly. Is Nature a gigantic cat? If so, who strokes its back?... I cannot exaggerate the effect of this marvelous night on my childish imagination. Day after day I have asked myself, what is electricity?"

Eighty years later, Tesla noted, that question was still preoccupying him. Here are four more surprising -- and entertaining -- cat facts, revealed by Pearson, co-host Mango Hattikudur and guest, writer Gabe Luzier:

To learn more little-known moments in cat history, listen to 9 Cat Facts in Honor of National Cat Herder's Day!

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