Science show

The stunt with the vacuum bulbs and the draft horses

Otto von Guericke (Magdeburg, November 20, 1602 – Hamburg, November 11, 1686)

It is now more than 350 years since the mayor of the German Magdeburg started one of his most famous popular science shows. Otto von Guericke took two bullet halves made of copper and bronze. They each had a diameter of 70 centimeters.

He transformed the two halves into a large sphere by means of a seal. He first sucked the air out of that sphere with a special pump.

He then pulled ropes through the rings attached to the sphere and had two horses pulled to separate them. Gradually he increased the number of horses, from four to six and so on until he reached eighteen.

Sometimes 24 horses were needed to make the sphere explode. In this way Van Guericke proved that there was such a thing as air pressure and that humans could indeed create a vacuum themselves. And that was evolutionary.

His first major showing took place in 1654 at the Reichstag in Regensburg, in the presence of the great Elector Friedrich Wilhelm of Prussia. Later, he continued to repeat that demonstration in front of high lords in the yard of his Magdeburg house.

Von Guericke lived another thirty years, and thirty years he would astonish the world with countless scientific demonstrations. He is also the inventor of the science show.

Biographers studying Von Guericke's life have always wondered where the hell he got the time from. Von Guericke was first and foremost a politician in difficult political times. He led a busy life.

The practice of the natural sciences, which would bring him great fame, was no more than a hobby.

Otto von Guericke was born to a wealthy family in Magdeburg in 1602. His father had been an envoy of the Polish king and had been given a title of nobility as a result.

From the age of fifteen Otto received the university education that was to prepare him for a political career. The last stage in this was Leiden in the Netherlands, at that time the most modern university in Europe.

In 1631 his beautiful Magdeburg was razed to the ground by Catholic troops.

Thousands of residents were killed. Von Guericke and his family barely escaped and found shelter with the Swedish king. When the tide turned and Magdeburg could be rebuilt, he was appointed mayor of the city.

For years he traveled to secure urban privileges through peace negotiations. For that purpose, for example, he stayed for a longer time in Nuremberg, then in Vienna, then in Prague.

In 1654 he appeared at the Reichstag in Regensburg, the place where he also performed his ball stunt en passant.

He only retired as mayor at the age of 76, after thirty years of service. A little later the plague broke out in the city and he fled to his son in Hamburg. There he died in 1684, aged 82. His corpse was brought home by ship across the Elbe; there he is buried in the cathedral.

In a book that he published when he was seventy, he explained in detail how he became fascinated by the phenomenon of air pressure, and how he put it on board to prove the existence of the vacuum, the vacuum.

It was generally assumed in those days that the vacuum did not exist, that it could not exist. He carried out many hundreds of experiments by trial and error. He tried to pump it with water from a barrel at first, but there was always air flowing through the cracks.

Then he made an attempt to put a keg in the larger keg and so on. Until he came up with the idea to extract the air directly from a sphere with a special pump.

He also studied how a sparrow behaves when it slowly runs out of air. 'First she gasped,' wrote Von Guericke, 'then she stood still for a moment and then she fell over.

This proves that the animal was unable to move due to lack of air, which simply extinguished the life in the heart.'

As spectacularly as with his copper spheres, he showed that the atmosphere presses on the earth. On top of a 10-meter-high pipe he placed a vacuum vessel. Then he put the bottom of the tube in a container of water.

He then let the air flow from the tube into the vacuum vessel at the top. And look there, the water from the tank was pushed up in the tube. The air pressure pushed the water upwards.

He also discovered the relationship between air pressure and weather. In 1660, he was the first in history to prove that a sudden drop in air pressure heralds the arrival of a thunderstorm.

So that Otto van Guericke may also be called the father of all meteorologists. "Experiments," he wrote, "should be given more importance than the judgment of stupidity, which is always making up prejudices against nature." Whoever wants to meet this wonderful man will find him in his beloved Magdeburg.

Since 1907 he has been sitting there life-size on a pedestal with his Magdeburg hemispheres on his left foot.