“Soothing, quieting and delightful beyond measure.” That was Queen Victoria’s description of chloroform, the anesthetic administered by her physician John Snow to ease labour pains as she gave birth to Prince Leopold in 1853. Snow was Britain’s leading anesthetist at the time, having followed in the footsteps of William Morton, who in 1846 had introduced ether anesthesia in Boston. Within a year, Snow had designed an ether inhaler and published On the Inhalation of Ether, a practical guide for the administration of the drug.
That same year, Scottish physician James Simpson discovered the sleep-inducing properties of chloroform. After dinner every night, Simpson and two assistants had the habit of experimenting with various chemicals to see if they had any anesthetic effect. Chloroform was a winner! Within days, Simpson had used it to perform minor surgeries, and when his patient Jane Carstairs experienced severe labour pains, he seized the opportunity to try chloroform for childbirth. A handkerchief soaked with chloroform placed over Carstairs’s mouth induced sleep and the unconscious mother proceeded to deliver a healthy baby! Some accounts claim she was so thankful that she named the baby “Anaesthesia.” It would be a great footnote to the story if it were true. It isn’t. The baby was named Wilhelmina.
Upon hearing of Simpson’s success, Snow investigated chloroform as he had done for ether, and found the drug to be more potent, but also potentially more dangerous. In 1848, he learned of the death of 15-year-old Hannah Greener who had been anesthetized with chloroform in preparation for minor surgery for an ingrown toenail. Within minutes Hannah became pulseless and died. Snow concluded that chloroform had to be administered in a carefully controlled fashion and engineered a vaporizer capable of delivering measured amounts of the drug. Queen Victoria, who had struggled through seven previous births and had referred to pregnancy as “the shadow side of marriage,” reaped the benefits.
The administration of an anesthetic for childbirth was not without controversy. Some physicians believed the relief of pain would slow the progress of labour, and the Church of England opposed easing pain in childbirth on theological grounds. Eve’s original sin doomed all women to bring children forth in pain! Opposition, however, was subdued after Victoria gave birth to Leopold, and later to Princess Beatrice, under chloroform anesthesia. If “chloroform à la reine” was good enough for Her Majesty, then surely it was good enough for all.
Most accounts of the history of chloroform begin with James Simpson’s self-experimentation and do not raise the question of where the chloroform came from. Delving into this makes the story even more interesting.
At the end of the 18th century, a group of wealthy Dutch amateur scientists formed the Batavian Society to study the new science of chemistry. In 1794, they reported treating alcohol with sulphuric acid to produce a gas that when bubbled into a chlorine solution yielded an oily fluid that came to be called “Dutch oil.” Today we know that the reaction of alcohol with an acid yields ethylene, and that ethylene reacts with chlorine to form dichloroethane. “Dutch oil” was dichloroethane, but of course, this was not known at the time.
Alcohol was available to the Batavians from fermentation, and sulphuric acid had been known since about the 8th century when alchemist Jabir ibn Hayyan heated “green vitriol” (iron sulphate) to produce “oil of vitriol,” the original term for the acid. And chlorine? That was discovered in 1774 by Swedish chemist Carl Wilhelm Scheele, who treated hydrochloric acid with the mineral pyrolusite (manganese dioxide).
In 1820, Glasgow physician Thomas Thomson found that an alcoholic solution of “Dutch oil,” for which he coined the term “chloric ether,” was a stimulant. American physician and amateur chemist Samuel Guthrie heard about this, and in 1831 thought he had found a simpler and cheaper way to produce the substance by reacting whisky with chlorinated lime (calcium hypochlorite). His sole evidence was that his product smelled like chloric ether and when inhaled produced a pleasant stimulating effect. He was wrong. What he had actually produced was chloroform.
Simpson’s legendary self-experimentation began when he learned about Morton’s introduction of ether as an anesthetic. Could he find something that worked even better? He tried chloric ether, but complained to his former medical school friend David Waldie that it didn’t work well. Waldie, who had given up medical practice in favour of chemistry, was familiar with chloric ether because he had distilled chloroform from it. Now he suggested that Simpson try pure chloroform.
The question was where to get the chemical. Simpson approached Edinburgh chemists William Flockhart and John Duncan, who had a small pharmaceutical firm. The two worked overnight to produce a pure sample of chloroform and the rest, as they say, is history. Duncan Flockhart & Co. Ltd. became the prime manufacturers of chloroform and supplied the British and Allied forces during the two world wars. It was the company’s chloroform that John Snow administered to Queen Victoria.
Chloroform was not problem-free. On occasion, it was found to cause respiratory failure and cardiac arrhythmia. When better anesthetics were developed, chloroform faded into the background. But it was still used in 1953 when I had my tonsils removed. I vividly recall the doctor pouring some on a gauze pad that was then clamped over my mouth. I was told that my tonsils were plucked out in a minute and a half, apparently setting a new record at the time. I would next encounter chloroform when I spilled some on my hand in the lab. The burning sensation between my fingers was not a pleasant experience.
Joe Schwarcz is director of McGill University’s Office for Science & Society (mcgill.ca/oss). He hosts The Dr. Joe Show on CJAD Radio 800 AM every Sunday from 3 to 4 p.m.
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