When we think of the pioneers of diving we think of the likes of Jacques Cousteau. He was of course instrumental in the modern development of the sport of scuba diving, but the sport did not develop because of just one person. The reason Cousteau was able to dive in safety can be attributed to the many who worked in the background to study what happens when the body is exposed to changes in ambient pressure. One such pioneering duo were father John Scott Haldane and his son JBS Haldane, both of whom have become as well known for their experimental anecdotes as they are for the discoveries they made to revolutionize dive safety.
Pioneers of Diving
JS Haldane was the personification of the eccentric 19th Century British scientist. He was born in Edinburgh in 1860 into a family of wealth and influence. He studied medicine at the University of Edinburgh and became an expert in the physiology of respiration. His interests ranged from studying decompression sickness and altitude sickness to hyperthermia, heatstroke and dehydration. JS Haldane was the first to realize that salt was essential in the prevention and treatment of dehydration, something else us divers can be grateful to him for. The American entertainer Oscar Levant once claimed there is a fine line between genius and insanity. As with many scientists operating at the time, JS Haldane definitely had some unorthodox methods, and there are many entertaining tales of his endeavors.
Haldane Senior frequently experimented on himself, as well as his wife and son. He was a true believer in his adage “All life is a physiological self-experiment”, a belief his son would also inherit. JS Haldane had an interest in toxic gasses, particularly during his early work, on the effects of carbon monoxide on miners. To test his theories in this topic, he carefully and systematically poisoned himself with carbon monoxide and measured his blood saturations as well as noting how he felt throughout the process. While doing this, he ended up with a CO saturation of 56%, which according to a doctor who examined him after the event, should have been lethal.
JS Haldane began his work on decompression sickness by observing the effect of pressure on several animals, but particularly goats because their body-mass to cardiac-output ratio is similar to a lean man. Initially he observed that with large pressure changes, the goats would show a range of signs that we now know are in line with the symptoms of DCS in humans. These included bends (normally the front limb was raised up), pain, temporary and permanent paralysis, illness, shortness of breath and death.
Bends in the foreleg of a goat after experiments performed by JS Haldane
Published in Journal of Hygiene, vol 8 1908 (public domain)
DCS had been known in military diving for a while, and it was definitely a problem. One autopsy on a navy diver in 1900 showed such severe bubble formation in the deceased’s heart and brain that those organs made a gurgling sound when the physician removed them from the corpse. Therefore in 1905, JS Haldane was commissioned by the British Royal Navy to investigate a way to help reduce the danger.
Haldane senior returned to his goat experiments, this time saturating the animals at the equivalent of 50m of seawater. He found that if the subsequent decompression was limited to half the change in ambient pressure, the animals did not develop DCS. Therefore JS Haldane constructed a model based on theoretical compartments with a specific “half time”.
To test his theory, JS Haldane didn’t just use a decompression chamber, he also conducted real dives from a ship off the coast of Scotland called the HMS Spanker. As per usual, JS Haldane had planned to participate in the experiment himself. He suited up in a diver helmet and suit that weighed 70 kg. Unfortunately JS Haldane had never learned to swim – something that he had apparently forgotten in all the excitement of the test – and he nearly drowned. In a later test designed to prove that the tables would also work with untrained people, Haldane senior carried out a dive with his 13 year old son. The diving suit was so big for Haldane Junior that it flooded, and he spent 30 minutes on the bottom of the Scottish sea in a suit full of chilly seawater somewhere around 8 – 11 degrees centigrade. When Haldane Junior was finally was brought to the surface the crew had to warm him up with blankets and whisky. How appropriate that the Haldane family motto is ‘Suffer”.
John Scott Haldane around 1920 from US National Library of Medicine
In spite of the occasional misadventure, in 1908, JS Haldane produced the first ever diving tables, based on a 5 compartment half-time model. It is the basis of several tables still in existence, and even through dive computers use a more sophisticated model, it is based on the same principle. When the table was adopted, cases of DCS fell drastically among Navy divers.
JBS Haldane never trained as a scientist – he studied Classics and Mathematics, but was considered a genius but those around him, and had been working with his father for years. He had even co-authored a published scientific paper with his father by the time he was 11 years old. JBS Haldane continued to experiment, clearly inspired by his father’s unconventional methods. The younger Haldane started his work on recompression with a view to developing a treatment for the condition. Volunteers sat in his recompression chamber and were subjected to pressure change extremes. The small chamber was soundproofed, and only had a tiny viewing window. Participants had to hold little notes up to the viewing window to keep the experimenters updated on their progress inside, or to convey any concerns the participants had. At one point Haldane simulated a dangerously fast ascent on himself to see what would happen. What happened was that the dental fillings in his teeth exploded. According to a colleague, almost every experiment ended with someone having a seizure, bleeding or vomiting.
On another occasion, while poisoning himself with dangerously high levels of oxygen, JBS had a fit so severe that he crushed several vertebrae. A similar experiment, this time with lack of oxygen, left Haldane without feeling in his buttocks and lower spine for 6 years. Regularly, participants complained of perforated ear drums, although Haldane cheerfully notes that “the drum generally heals up; and if a hole remains in it, although one is somewhat deaf, one can blow tobacco smoke out of the ear in question, which is a social accomplishment.”
So even though these endeavours are entertaining to learn about, it’s impossible to underestimate the importance of the work of this slightly bizarre pair. In essence, John Scott and JBS Haldane’s work paved the way for all of us to go diving. So next time you descend under the surface of the water, you can offer up thanks to the Haldanes (and their brave volunteers) for enabling you to enjoy a safe and happy dive.