Today I want to tell you about Jan Baptist van Helmont, a chemist, alchemist, physiologist and physician who was born in Brussels in 1580 and died on this day in 1644. He studied the classics and was taught magic and mystical philosophy by the Jesuits before settling on a study of medicine. He practised medicine until he married money, then he devoted himself to a study of chemical philosophy. Van Helmont was both a man of science and a man of God and I’m always rather impressed by people who manage to make advances in scientific knowledge despite their belief in a divine creation.
Van Helmont refuted the idea that there were four elements: earth, air, fire and water. He believed that there were only two. Fire, he said, was definitely not and element and neither was earth as he felt it could be reduced to water. In his universe, there was air and everything else was made of water in some form. His theory was, he thought, supported by the creation story found in the book of Genesis. He carried out an experiment which would prove that a tree is made of water. People generally believed that a tree grew by eating soil, which is a delightfully quaint idea. Van Helmont got himself a small tree and weighed it. It weighed 5 lb. Then he weighed out 200lb of dry soil, put it in a pot, planted the tree and watered it. He kept the tree and continued to water it for five years. At the end of that time, he took the tree out of the soil and weighed it again. It weighed 169 lb. When he dried out the soil and weighed that, he found that it was only 2oz lighter than when he started. The tree had eaten hardly any of the soil. As he had given it only water, the tree must be made of water. Of course, he didn’t understand anything about photosynthesis and didn’t know that the tree had also taken carbon from the air. But then he thought air was an element and wasn’t made of anything except itself.
This is odd as he did know about gas. In fact he invented the word. Gas was, of course, another form of water which was liberated by heating. In another experiment, he burned 62 lb of charcoal and found he was left with only 1 lb of ash. The rest had escaped during the burning in the form of some kind of wild spirit he called ‘gas sylvestre’ but what we would call carbon dioxide. No one is sure where he got the word ‘gas’ from. It may be derived from the Greek word ‘chaos’ or from the word ‘gahst’ which means ghost or spirit. He believed the same gas sylvestre was produced by fermenting alcohol and that it was what rendered the air in some caves unbreathable.
Among his other discoveries was the fact that chemicals were involved in the digestion of food. People had thought that digestion was caused by heat, but van Helmont realised if that were true, cold blooded animals like snakes would not be able to digest their meals. Unfortunately he thought that the fluids involved in digestion were governed by spirits that needed to be kept in balance, but that’s alchemists for you. But it did lead him to successfully treat stomach complaints caused by and excess of acid with an alkaline remedy.
Not much of the work of van Helmont was published during his lifetime. Early on he waded into a massive controversy that landed him in trouble with the Inquisition and that probably put him off. There was quite a heated debate going on between the Jesuits and followers of a physician called Paraclesus, of whom van Helmont was one. It was over a cure known as the ‘weapon salve’. A wound could be cured by applying a special ointment to the weapon that had caused the injury. If you read the ingredients, there’s no way you would want to put it on an actual wound. It requires ‘man’s grease’ and some moss which has grown on the skull of a person who has met a violent death. Surprisingly, the debate was not about whether it worked at all, but why it worked. The Jesuits felt that it was all the devil’s work and should be left well alone. Van Helmont believed that it worked because there was a magnetic attraction between the blood on the weapon and the blood coursing through the veins of the patient. This kind of sympathetic magic was very real to people in seventeenth century Europe. He further went on to explain that it probably worked in the same way that sacred relics produced miracles. This was a mistake. He was suspected of heresy and it earned him two years of house arrest. He was not fully absolved until after his death. A lot of his work was published posthumously by his son who, by our standards, was even more odd and esoteric that his father. Which is probably why not many people have heard of him.