Otto von Guericke (UK: GAIR-ik-ə, US: G(W)AIR-ik-ə, -ee; German: [ˈɔtoː fɔn ˈɡeːʁɪkə] ; spelled Gericke until 1666; 30 November [O.S. 20 November] 1602 – 21 May [O.S. 11 May] 1686) was a German scientist, inventor, mathematician, and physicist. His pioneering scientific work, the development of experimental methods and repeatable demonstrations on the physics of the vacuum, atmospheric pressure, electrostatic repulsion, his advocacy for the reality of "action at a distance" and of "absolute space" were noteworthy contributions for the advancement of the Scientific Revolution.
Otto von Guericke was born to a patrician family of Magdeburg. He was privately tutored until the age of fifteen. In 1617 he began studying law and philosophy at the Leipzig University. However, in 1620 his studies were disrupted by his father's death. He briefly returned home before continuing his studies at the Academia Julia in Helmstedt and the universities of Jena and Leiden. It was at Leiden that he first attended courses on mathematics, physics and military engineering. He concluded his academic education with a nine-month Grand Tour to France and England.
Upon his return to Magdeburg in 1626 he married Margarethe Alemann, with whom he had three children (Anna Catherine, Hans Otto, and Jacob Christopher) before her untimely death in 1645. Anna Catherine and Jacob Christopher both died in infancy and in 1652 von Guericke married Dorothea Lentke.
Von Guericke was the offspring of one of Magdeburg's leading patrician families, that were well-educated and well-connected. His father and grandfather had been life-long members of the city council and at various occasions during their careers been appointed to serve as mayor of the city. In 1626, Otto von Guericke started his career as political representative of Magdeburg and accepted an official appointment to join the city council. However, in 1618, the Thirty Years' War had broken out. This exceptionally long, tragic and destructive conflict would soon also descend upon Magdeburg. Only a few years later, he had luckily fled from the city before an army of the imperial Catholic League, led by the Count of Tilly had completely surrounded and cut off Magdeburg. The attack culminated in the single most devastating event of the entire war, namely the Sack of Magdeburg. In May 1631, the imperial troops had crushed the city walls and indiscriminately plundered the riches. Around eighty percent of its more than 25,000 inhabitants perished. The material loss was also unusually high as widespread fires destroyed about 1,700 of a total of 1,900 buildings, including all of von Guericke's personal property. He returned to Magdeburg in 1631 and his academic engineer education designated him an appointee of the reconstruction committee.
He became a master brewer in an attempt to speedily acquire a new personal fortune and accumulate wealth for the city. In 1646, he was elected as Magdeburg's Burgomeister, the city's chief magistrate or executive, an office that arguably bestowed more power (in a practical sense) than that of a mayor. He held this position until his retirement in 1678. During four decades in office he undertook numerous diplomatic missions, which took him to many European courts and councils, where he met powerful executives and secretaries and addressed the illustrious elite of dukes, kings and emperors. In 1666, Otto von Guericke was ennobled by emperor Leopold I, which, apart from entitling him to add the "von" prefix to his name, was of little consequence. He also altered the spelling of his last name from "Gericke" to "Guericke".
Otto von Guericke's first diplomatic mission on behalf of the city led him in September 1642 to the court of the Elector of Saxony at Dresden. Von Guericke's mandate was to bring about a more lenient treatment from the Saxon military commander for Magdeburg. In 1648, he represented the city at the peace treaty delegation, that ended the Thirty Year's War. During a 1654 diplomatic mission to Regensburg, Guericke presented his invention of the air-pump to impress those he was going to meet and help sway the talks in his favour, as well as promote his own scientific achievements. Diplomacy assignments, often dangerous as well as tedious, would occupy much of his time for the next twenty years. His private life, of which much remains unclear, was developing in parallel. Otto von Guericke utilised both his official status and his scientific knowledge in each other's support to serve his city's political agenda. Demonstrations of his inventions, such as the air-pump and the electrostatic generator were meant to impress his audiences and improve and extend political communication. He would, if necessary forgo scientific and technical elaborations on how his showpieces worked, leaving people to believe in his wizardry, a characteristic that was of great use for the promotion of a great leader.
Initial scientific investigations
Curious and inspired by the Copernican cosmology and hardly understanding new ideas of vast, endless, empty space where light would propagate, bodies of matter could move about unhindered, and sound cannot be detected, von Guericke set about replicating this nothing phenomenon on Earth. Von Guericke first started investigating the concept of a vacuum through the use of fire pumps by pumping water out of wooden barrels. However, he soon realised that the porosity of wood was allowing unwanted water, filled with dissolved air, to enter. The pressure fluctuations experienced inside the barrel were allowing this encapsulated air to escape: spoiling the vacuum inside. In 1647 he turned his focus to pumping out enclosed air instead of water to solve this problem.
Merging of his scientific and political careers
His scientific and diplomatic pursuits finally intersected when, at the Reichstag in Ratisbon in 1654, he was invited to demonstrate his experiments on the vacuum before the highest dignitaries of the Holy Roman Empire. He built a vacuum pump, pumped air out of two joined Magdeburg hemispheres, attached a team of horses to each side, and had them pull. He demonstrated this again to the King of Prussia in 1663 and was awarded a lifetime pension. One of these dignitaries, the Archbishop Elector Johann Philipp von Schönborn, bought von Guericke's apparatus from him and had it sent to his Jesuit College at Würzburg. One of the professors at the college, Fr. Gaspar Schott, entered into friendly correspondence with von Guericke and thus it was that, at the age of 55, von Guericke's work was first published as an Appendix to a book by Fr. Schott – Mechanica Hydraulico-pneumatica – published in 1657. This book came to the attention of Robert Boyle who, stimulated by it, embarked on his own experiments on air pressure and the vacuum, and in 1660 published New Experiments Physico-Mechanical touching the Spring of Air and its Effects. The following year this was translated into Latin and, made aware of it in correspondence with Fr. Schott, von Guericke acquired a copy.
In the decade following the first publication of his own work von Guericke, in addition to his diplomatic and administrative commitments, was scientifically very active. He embarked upon his Magnum Opus—Ottonis de Guericke Experimenta Nova (ut vocantur) Magdeburgica de Vacuo Spatio—which as well as a detailed account of his experiments on the vacuum, contains his pioneering electrostatic experiments in which electrostatic repulsion was demonstrated for the first time and he sets out his theologically based view of the nature of space, but there are also contemporary arguments that he did not conceptualise these demonstrations as electrical. In the Preface to the Reader he claims to have finished the book on 14 March 1663, though publication was delayed for another nine years until 1672. In 1664, his work again appeared in print, again through the good offices of Gaspar Schott, the first section of whose book Technica Curiosa, titled Mirabilia Magdeburgica, was dedicated to von Guericke's work. The earliest reference to the celebrated Magdeburg hemispheres experiment is on page 39 of the Technica Curiosa, where Schott notes that von Guericke had mentioned them in a letter of 22 July 1656. Schott goes on to quote a subsequent letter of von Guericke of 4 August 1657, in which he states that he now had carried out the experiment, at considerable cost, with 12 horses.