John Walker is remembered by the scientific community as a truly unique researcher of the natural world. Students at the University of Edinburgh had the honour of attending his lectures, where he held the position of Professor of Natural History. Furthermore, he was directly involved in the creation of the Royal Society of Edinburgh, serving as one of its founding members. Read more about at edinburgh1.one.
Early Life and a Dual Calling
Walker’s life began in 1731 in the city of Edinburgh. His father was the head of a local grammar school, so it is no surprise that great importance was placed on the boy’s education. After finishing school, John became a student at the University of Edinburgh in 1746.
Interestingly, it was common at the time for ambitious Scottish men to obtain a degree in divinity. This was a path Walker also followed, earning his degree in 1749. In 1754, the young man was licensed to preach. He was soon ordained as a minister in the Church of Scotland, eventually becoming a parish minister. However, his clerical duties did not become an obstacle to his scientific pursuits.
The Beginning of a Scientific Journey
While a university student, he attended courses in natural philosophy. In the 1750s, he began to study chemistry under the guidance of Professor William Cullen. In addition, Walker became a member of the Philosophical Society of Edinburgh, where his successes were recognised with various awards. A true milestone, however, was the publication of his article in the prestigious journal, “Philosophical Transactions of the Royal Society”.
It is also important to note that Cullen managed to unlock his protégé’s talent as a mineralogist and chemist. This later enabled John to become a scientific advisor to influential figures such as Lord Bute, Lord Hopetoun, and Lord Cathcart.
Surveys of the Highlands and Islands
The 1760s were marked by new opportunities. Thanks to his connections, John was able to visit the mines of the Lowlands, a trip that resulted in his own personal mineralogical collection.
By the mid-1760s, John was known as Scotland’s leading naturalist. This reputation prompted the Church of Scotland and the Board of Annexed Estates to give him the opportunity to take part in research trips to the Hebrides and the Highlands. These journeys, which took place in 1764 and 1771, allowed John to make valuable observations of a religious and ethnographic nature. And, of course, during his travels, he made important scientific notes on the local terrain, minerals, plants, animals, and climate.
For instance, when Walker travelled to the island of Jura in 1764, he provided a detailed description of what is now known as Lyme disease, right down to the symptoms and the tick that carried it. At the same time, John was also collecting samples of a mineral that would later become known as strontianite. This discovery initiated the process of analysing and identifying the new alkaline earth element, strontium.
The Contest for the Professorship
Having gained rich scientific experience and valuable research results, John became one of the most popular authors for The Scots Magazine and Philosophical Transactions in the 1770s. It soon became clear that Robert Ramsay, the Professor of Natural History at the University of Edinburgh, was seriously ill, making the question of his replacement a pressing issue. With the support of William Cullen, Lord Kames, and other allies, John Walker decided to contest the position. His opponent was William Smellie, a respected naturalist and well-known publisher. After a lengthy dispute, Walker emerged victorious. In 1779, he was appointed to the professorship, a post he held until his death in 1803.
A Legacy in Teaching
John’s natural history lectures were divided into two parts, which students attended throughout the academic year. The first half consisted of “Hippocratic” lectures, which covered meteorology, hydrology, and geology. In the second part, Walker discussed minerals, plants, and animals.
It is worth noting that in the 1760s, John applied Linnaeus’s binomial nomenclature to botany. However, he disapproved of Linnaeus’s classification for minerals and animals and decided to develop his own system. In addition, using geochemical and historical data, Walker created a complex theory of the Earth.
By the late 1790s, however, John’s eyesight began to fail, so he passed some of his lectures on to his former student, Dr. Robert Jameson. Nevertheless, by the end of his life, Walker had imparted knowledge to over 800 students, many of whom went on to become highly significant figures in 19th-century natural history.
John Walker’s life came to an end on 31 December 1803. The scientist died in his own home in Edinburgh and was buried in one of his native city’s graveyards.