IT was in this week 312 years ago that William Cullen was born. One of the major figures of the Scottish Enlightenment, it is my firm belief that he should receive far greater credit for his invention of modern artificial refrigeration and that he should be ranked alongside Alexander Graham Bell and John Logie Baird for an innovation that changed the world.

Cullen did not invent the concept of refrigeration – as with so many developments, that idea took shape in ancient China and Egypt and was followed up by the Greek and Roman civilisations. Their form of refrigeration was based on gathering ice and snow in pits and then covering them up with insulating materials.

By the 17th century, ice houses were a common sight across Europe and there was a growing international trade in ice led by the Scandinavian countries. There was no artificial refrigeration, however, though plenty scientists had theorised that it was possible.

Enter William Cullen. Born in Hamilton on April 15, 1710, Cullen was the son of a lawyer employed by the Duke of Hamilton. He was educated at the local grammar school and then Glasgow University.

Thanks to a biography written by his grandson John Thomson (1765-1846) we know almost every detail of Cullen’s life.

He studied at the University under surgeon and anatomist John Paisley, then gained surgery experience on a merchant vessel trading across the Atlantic before settling briefly in London as an assistant apothecary. In 1732 he came home to Scotland and set up a general practice in Shotts, and from 1734 to 1736 he studied at Edinburgh University’s then-new medical school. As a first-year student in Edinburgh he was a co-founder of the Royal Medical Society whose members down the centuries have included Benjamin Franklin, Joseph Lister and Charles Darwin.

A true lad o’pairts who took an interest in multiple subjects such as botany and agriculture, Cullen had been developing an interest in the fledgling science of chemistry, especially practical research, and he maintained these interests even while setting up and running a successful private practice in Hamilton where the Fifth Duke of Hamilton was a patient.

According to the biography on Glasgow University’s website, it wasn’t just the entitled few who benefitted from Cullen’s ministrations: “He spent eight years in private clinical practice, attending without fee those too poor to afford his service.”

He was awarded his doctorate in medicine by Glasgow in 1740, and married his wife Anna née Johnstone, a daughter of the manse, the following year – their seven children would include the physician Henry Cullen and the judge Robert, Lord Cullen, who would help their father found the Royal Society of Edinburgh.

After the death of the Duke of Hamilton in 1743, Cullen began a series of lectures at the University on chemistry and medicine, the first to be given in the UK. These were hugely influential and popular, and led to the University appointing Cullen as a full-time lecturer in 1747.

By all accounts he was a brilliant and inspirational teacher, but it is for one part of his chemical research that Cullen should be better known. While still in his teens he had developed theories about cooling and at Glasgow University he was able to research the chemistry of cooling and put these ideas into practice.

So it was that the world’s first artificial refrigeration was performed by Cullen in Glasgow in 1748 with the world’s first demonstration of practical refrigeration eight years later. He used a pump to create a vacuum in a container of diethyl ether and when the diethyl ether began to boil, it absorbed the heat from its surroundings and began to cool. Some accounts say ice could be seen.

He would carry out further experiments over the years and recorded his research in his only chemistry-related publication Of The Cold Produced By Evaporating Fluids, And Of Some Other Means Of Producing Cold, which again is further evidence that he invented artificial refrigeration.

The trouble for Cullen was that there was no practical use for his invention at that time, and the ice suppliers were not interested. It would not be until the 19th century that American scientists and inventors, some of them taught by people who had been students of Cullen, began to take interest in refrigeration, which is why Jacob Perkins (1766-1849) is credited by many as the father of the refrigerator as he gained the first patent for such a device.

The National:

It was in Edinburgh as a physician and professor that Cullen reached the height of his fame as he became a leading figure in the Scottish Enlightenment, a friend to David Hume (above), Adam Smith and all the greats of the Enlightenment. His works on medicine were published across Europe and in America. They included Institutions of Medicine Part 1 Physiology, 1772, First Lines on the Practice of Physic in four parts published between 1777 and 1784 and Treatise of the Materia Medica, 1789.

Much of his medical practice was carried out by letter as the titled and wealthy across Scotland and beyond insisted on being treated by the county’s most eminent doctor. His theories that many illnesses were caused by trouble with the nervous system led him to coin the word “neurosis”, and while he did not use the word “placebo” first, he was the first to use it in a medical context.

Cullen died on February 5, 1790, at the age of 79. For all his many achievements, it still rankles with some people that he is not truly accorded the invention of artificial refrigeration and allowed to take his place in the pantheon of Scottish inventors.