This is a story about an air-pump. Or, rather, it is a story about one of the first ‘fact-factories’, constructed in the 17th century in the intellectual centers of Western Europe. During that time, a new philosophical practice was emerging, specializing in the production of new phenomena under artificial circumstances. This practice came to be called ‘experimental philosophy’, and its products ‘facts’. Now, in our eyes, it may seem obvious that the natural sciences take place in laboratories and concern themselves with facts, but during the 17th century, this was all but taken for granted. Indeed, when we step into the 17th century laboratory, we see how, there, the fight for the boundaries of what counts as ‘good science’ was being fought out.
For our story, we have reproduced certain experiments performed with the air-pump of Christiaan Huygens. They will serve as a magnifying glass through which we can observe more closely how during the 17th century, the production of facts took shape.
The first air-pump was built by Otto von Guericke in 1654, while he was performing experiments on the effects of a vacuum. His experiments touched upon the centuries-old-debate over the possibility of a void. This debate had always been a matter of speculation, in which philosophers debated over the right definition of concepts such as ‘air’, ‘void’ or ‘velocity’. Relying on Aristotle, it was for instance argued that the idea of a void implied a contradiction. The speed of a falling object was related to the density of the medium in which it fell. In a completely empty medium, the speed of the object would be infinitely large, and that would be absurd. With the experiments performed by his air-pump, however, von Guericke claimed to have offered experimental proof that a void was possible, thereby granting his air-pump the power to end a centuries-old debate with one simple experiment. Knowledge was no longer to be found in the right definitions of concepts or abstract speculation, but in the laboratory.
By producing ‘matters of fact’, natural philosophy seemed to have found a way to abandon speculative debates such as the one on the question of the void for once and for all. This ambition was pursued by Robert Boyle. After reading about von Guericke’s air-pump in 1657, Boyle (or rather: his instrument-maker Robert Hooke) manufactured a pump of his own. While designing and performing experiments, carefully described in his New Experiments Physico-Mechanicall, Touching the Spring of the Air, and its Effects, Boyle became an important ambassador of the experimental practice.
This new practice was, however, not established without resistance. The legitimacy of experimental instruments such as the air-pump was heavily debated. How can artificially produced experiences under carefully controlled circumstances tell us something about phenomena in the world outside the laboratory? How can a feather falling in a glass dome devoid of air tell us something about a leaf falling from a tree in the woods? Imagine you asked me why I ended my relationship, and for an answer I referred to something I had observed watching Temptation Island (or some other reality-show environment filled with unusual, or at least unusually prolonged, stresses). You would probably think that I was mad, rather than accept that as a legitimate explanation.
Although Boyle will be an important figure in our story, the main role is played by the air-pump of Christiaan Huygens. As a real experimental philosopher, he visited the Royal Society in London in 1660 to watch the performances of fellow experimentalists. He saw Boyle’s air-pump at work, and back home in Holland he started building his own pump, trying to improve the design of Boyle’s pump. By the end of November 1661, he had a pump which was, so he wrote to his brother, at least as good as Boyle’s. During 1661 and 1662 Huygens performed various experiments with his pump, many of which were replications of the ones described by Boyle in his New Experiments, and some of which we will re-enact here. By following the journey of the facts produced in Boyle’s laboratory to Huygens’s laboratory and back to the Royal Society, we will see how the production of facts slowly took shape.