Schematically: blue: two hollow half spheres, red: seal, yellow: aspiration of the air. Original Maagdenburg half-spheres with vacuum pump, in the Deutsches Museum in Munich
The Maagdenburger half spheres are two loose half spheres of strong material that are held together, after which the space is sucked into the so-called sphere of vacuum. Due to the air pressure on the outside surface, the half-spheres are pressed against each other.
This experiment was first carried out by Otto von Guericke, the Mayor of German Maagdenburg, in 1654. Sixteen horses were unable to separate the two ball halves with a diameter of approximately 50 cm. The force that had to be overcome was therefore more than 20,000 N, which is equal to the weight of a mass of 2 tons. Von Guericke thus demonstrated the size of the ground-level air pressure, which is due to the weight of the earth's atmosphere. Von Guericke has developed into the founder of the vacuum technology. Trivia
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