Imagine showing someone from the 1920s a wireless earbud.
It might look like a tiny piece of plastic with no obvious purpose.
Likewise, show someone who has only ridden modern bicycles an old bottle dynamo and they may have no reason to associate the object with bicycles at all.
That is the central trick behind these viral identification puzzles.
The object itself has not changed.
Our familiarity with it has.
A Forgotten Piece of Bicycle History
Bicycle dynamos are particularly interesting because they belong to an earlier period of everyday technology.
For many years, bicycle lighting was a mechanical problem.
Riders needed to be visible at night, but carrying batteries could be inconvenient. Rechargeable batteries were not nearly as convenient as they are today, and compact modern lighting systems had not yet transformed the market.
The dynamo provided a clever alternative.
Attach it to the bicycle.
Let the tire turn it.
