Why 30 Horses Couldn't Pull Two Empty Bowls Apart

In 1654, thirty horses pulled as hard as they could, and they still could not separate two metal bowls.

No glue. No bolts. No latch. The mayor of Magdeburg just pressed two copper hemispheres together and pumped the air out. So what was actually holding them shut?

Air is not weightless. The atmosphere stacks miles above us and pushes on every surface, about 14.7 pounds per square inch. We never feel it, because air inside an object pushes back out with equal force. Otto von Guericke broke that balance. He pumped the air out of the sphere, so nothing pushed back from inside. With the inside empty, the whole weight of the sky pressed in from every direction at once, sealing the halves like an invisible vise.

Here is the strange part. The instant he opened a valve and let air rush back in, the hemispheres fell apart in his hands. That same force was acting on you this entire video, pressing on your skin right now.

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