
A Schott diagram depiction of German engineer Otto Guericke's famous circa 1645 beer keg vacuum experiment, in which Guericke and another man (or Guericke's two assistants) try to completely evacuate the air form a well-caulked beer keg, so to see if a "vacuum" could be made, the existence of which that was deemed impossible by both Aristotle and Parmenides, among others

A Schott diagram depiction of German engineer Otto Guericke's famous circa 1645 beer keg vacuum experiment, in which Guericke and another man (or Guericke's two assistants) try to completely evacuate the air form a well-caulked beer keg, so to see if a "vacuum" could be made, the existence of which that was deemed impossible by both Aristotle and Parmenides, among others

In experiments, beer keg vacuum experiment, depicted adjacent, was a circa 1649 experiment in which water or wine was either drained or sucked out of a well-sealed beer keg to see if an vacuum (or Torricelli-type vacuum) could be made, conducted by German engineer Otto Guericke. [1]

Overview
In c.1645, Otto Guericke, based on the dating of the invention of his vacuum pump (1647), as evidenced below, carried out his famous beer keg vacuum experiment, as illustrated adjacent.

“The vacuum pump, for which Guericke is most celebrated, has been dated to 1647, but that too must have been the culmination of work going back to earlier years, e.g. Guericke’s grandson, who died in c.1790, recorded in his History of the Duchy of Magdeburg, that he possessed an astrolabe and a spirit level on which were engraved: ‘fait par Otto de Guericke, engineer at Magdeburg 1632.”
— Thomas E. Conlon (2011), Thinking About Nothing (pg. 43)

The Guericke beer keg vacuum experiment was an experiment to see if a vacuum could be made in a beer keg and performed by German engineer Otto Guericke.

It has been said or surmised that Guericke may have been stimulated or influenced in some way or another into his beer keg experiment by a mixture of hearing about Aristotle’s denial of the void, Galileo’s theoretical investigations on the pump problem, and in particular the rumored 1643 Torricelli mercury column experiment in which a Torricelli vacuum was made. [2]

In circa 1648, German engineer Otto Guericke, after ending a prolonged engagement with the 30 Year War, began to devote a considerable portion of his spare time to experimentation and was especially fascinated with the nature of cold, much of which was centered on the question of the void. Guericke pondered the question: [3]

“Could empty space exist, and is heavenly space unbounded?”

In researching this query, Guericke was brought into contact with German mathematical physicist Gaspar Schott, an adherent to Aristotle’s version of the denial of the void, albeit open to new experimental information, the person who would go on to diagram and document all of Guericke's numerous experiments.

The first part of the keg experiment seems to have been only to make a Torricelli vacuum in the keg by letting water or wine drain out the bottom of a previously completely full keg. Guericke explains the experiment as such: [4]

“I had a wine or beer keg filled with water and well caulked throughout so that no external air could enter. I introduced a bronze tube, attached to the lower part of the keg by means of which water could be drawn out. Then through its own natural weight [natural vacuum], the water would of necessity go down and leave behind in the keg a space of air (and accordingly empty of any natural body).”


The 1643 Torricelli vacuum experiment, the prototype model, it is said, that German engineer Otto Guericke experimentally tested to see if vacuum's could be made in beer kegs.

The 1643 Torricelli vacuum experiment, the prototype model, it is said, that German engineer Otto Guericke
experimentally tested to see if vacuum's could be made in beer kegs.

The second version of the experiment seems to have involved a type of suction pump with two men working the pump to remove contents from the keg, as depicted above (a Schott diagram) and thus make an extra strong vacuum or rather an "artificial vacuum" as it might be deemed in modern terms.

Results
The result of Guericke's beer keg experiments were that (a) they seemed to have resulted in the bi-product invention of the vacuum pump (and hence to the pneumatical engine and later the gas laws) and (b) they introduced him to the "sealing problem", i.e. how to make a container air tight. The solution to this problem was the invention of the famous Magdeburg hemispheres, two copper hemispheres sealed by grease, such that when the vacuum was induced inside the volume of the globe of the two attached and fitted hemispheres, the pressure of the surrounding atmosphere worked to hold or rather seal the hemispheres very tightly.

When the two hemispheres are simply laid together and the air exhausted from the inner space and if the vacuum could be made perfect in a sphere whose cross section is one square foot, the force required to separate the hemispheres would be 2116.8 pounds, or something less than one ton.

Naturally the discovery of the immense force of the atmosphere caused many attempts to utilize it. Denis Papin, professor of mathematics at Marburg, found the true solution in 1696, but did not meet with practical success; his first large steam cylinder, the Papin engine, in an unfinished condition stands in the court of the museum of Cassel. It is an undoubted fact that he did make an atmospheric engine work by the condensation of steam in a cylinder fitted with a piston. [5]

In short, skipping over a bit of intermediate history, Guericke's beer keg experiments directly led to the invention of the steam engine by Denis Papin and hence to the formulation of the subject of thermodynamics.

References
1. (a) Schott, Gaspar. (1657). Mechanical Hydraulic Pneumatics (Mechanics of Gas Hydraulics), Otto Guericke’s work in appendix. Würtzburg.
(b) Guericke, Otto and Schott, Kaspar. (1672). Otto Guericke’s New Experiments on (as they are called) on the Magdeburg vacuum space (Ottonis De Guericke Experimenta Nova (ut vocantur) Magdeburgica de Vacuo Spatio) (15+ diagrams, various pages). Janssonius a Waesberge.
2. Craik, George L. (1831). The Pursuit of Knowledge under Difficulties (pg. 81). C. Knight.
3. Partners and Rivals during the Scientific Revolution – Faculty.Fairfield.edu.
4. Guericke, Otto. Ames, Margaret G.F. (1994). The New (so-called) Magdeburg Experiments of Otto von Guericke (pg. 114). Kluwer Academic.
5. Marks, W.D. (1882). “Talks on the Steam Engine” (pg. 108), The Engineer: with which is incorporated Steam engineering, Volumes 3-4.

Further reading
● Logan, William B. (2005). Oak: the Frame of Civilization (pg. 179). W.W. Norton & Co.