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Chemistry – a natural science?
For a long time, chemistry was a discipline which lagged behind other natural sciences. The human desire for cheating death and overcoming poverty was just too strong for people to abandon the promises of alchemy and embark into the scientific study itself.
This article, which is the first in our four-part series on the history of chemistry, will explore how chemistry left behind the mysticism of alchemy.
The origins of chemistry
Humans have been fascinated with chemistry for thousands of years. The first use of chemical processes dates back to the fourth millennium BC and involved extracting metals from mineral ores. However, the shift from chemistry as a mere practical utility into a full-blown scientific debate with its many fields of enquiry happened much later. It wasn’t until the times of Ancient Greece that natural philosophers documented this kind of engagement with nature and the resulting attempts to explain the world as it appears to us.
For example, Democritus (ca. 460–371 BC) was concerned with the structure of matter. Like his mentor Leucippus, he was convinced that matter was composed of tiny, indivisible particles. It was Democritus himself who coined the term «atom», derived from the Greek word «átomos» (in English, «indivisible»).
Alchemy – a secret science
The theoretical principles of the Greek natural philosophers later gave way to alchemy, which, like the modern sciences, aimed at extracting knowledge about nature by conducting experiments.
These ideas were spread from Greece to Egypt and Babylon, and also reached medieval western Europe much later on. However, the progress of alchemy was beset with numerous stumbling blocks for a long time. Some of the basic premises of alchemy, which were not based on observations of nature but on mysticism and superstition, stood in the way of real scientific discoveries. To make things worse, alchemical technical language was inconsistent and, furthermore, remained intentionally vague and incomprehensible in order to exclude outsiders from its secrets.
Regardless of their faults, the alchemists of the Middle Ages had – for their time – a solid basic understanding of science. They learned to experiment with materials, and they understood better than anyone else how to isolate pure substances and constituents of matter, and to create new mixtures. The alchemists’ abilities qualified them to work in mines, mints, as blacksmiths, and in apothecaries.
During their tenure in these positions, they isolated hitherto unknown substances, improved food preservation methods, and created alloys – yet scientific discoveries remained few and far between. The basic foundations of alchemy were not quite ready to give rise to a comprehensive, systematic approach to chemistry.
Cartesian doubt
Objective research into the natural world became possible for the first time when the thinkers of the Renaissance began to question everything which was not clear as day and obvious beyond a shadow of a doubt.
The French philosopher René Descartes (1596–1650) revolutionized the natural sciences with his method of doubt, whereby assumptions could be scrutinized in order to generate knowledge systematically. Even the teachings of religious authorities were thrown into doubt, which at that time was a massive taboo. Descartes also advocated mathematics as the basis of all natural sciences, allowing us to describe and explain nature not only qualitatively, but also quantitatively.
In the field of physics, Descartes’ ideas gained quick acceptance and were seized on and developed further by other scientists, including Isaac Newton (1643–1727). The work of Descartes and Newton was the catalyst for rapid progress in physics and astronomy, yet chemistry still lagged behind: Newton himself spent his life in pursuit of the «philosopher’s stone» – a material which could supposedly turn base metals into gold by the process known as «transmutation».
The transition from alchemy to chemistry
Robert Boyle (1627–1692) was a pioneer in modern chemistry. Among the first to attempt to consolidate the alchemists’ knowledge concerning material properties and reactions into a comprehensive theory, he demystified chemistry along with its nomenclature.
It was Boyle who defined the «element» as the end product of analysis, i.e., as pure substance. His rational approach was, up until that time, unique in the field of chemistry. He published his findings in his groundbreaking 1661 work «The Sceptical Chymist». This publication heralded the transition from alchemy into chemistry, which can be seen in the title of the book as the prefix «al» is dropped. Nevertheless, Boyle practiced alchemy until the end of his life and continued to believe in transmutation. The ultimate breakthrough of chemistry had to wait until the early 19th century.
Digression: Electrochemistry
In 1800, Alessandro Volta (1745–1827) developed the first battery: the voltaic pile. With this invention, the history of electrochemistry had begun. The pile consisted of stacked, alternating copper and zinc plates, each separated from the next by fabric soaked in electrolyte solution. Humphry Davy (1778–1829) used the pile in his electrochemical experiments and in 1807 and 1808 discovered numerous elements (including sodium, potassium, calcium, and magnesium) by electrolyzing saline solutions or hot, molten salts.
Davy also isolated chlorine, which reacts with water to form hydrogen chloride, through the electrolysis of saline solution. Until this time, it was assumed that oxygen was the key component of all acids. However since no oxygen is found in hydrogen chloride, Davy discovered that it was hydrogen which gave a compound the properties of an acid.
In the next installment, we will cover the return to atomism and the rise of modern chemistry between the 18th and 19th centuries. Click below to go directly to the next post!
