Why do we even want to breath underwater? The answer might delight you. As scuba diving technology has advanced, so too has humanity’s understanding and care of the oceans.
This episode tracks the development of humanity’s desire to breath and explore underwater. From the first free divers trying to find the softest sea sponges, through to great innovations that allow scientists and explores to go deeper for longer. The development of SCUBA equipment closely relates to humanity’s understanding of the ocean environment and humanity’s desire to protect this precious region.
First diving bell
Aristotle wrote about the first diving bell known to exist
Venice under attack
While in Venice while it was being attacked, Leonardo Da Vinci designed a leather diving suit with a bag-like mask that would go over the diver’s head… but this was never made
Conserve and sustainably use the oceans, seas and marine resources
Today on Idea Evolution we’re talking about the evolution of scuba diving.
Did you know that the word SCUBA isn’t actually a word… it’s an acronym. So each of the letters in SCUBA S-C-U-B-A stands for a real word. SCUBA really means Self-Contained Underwater Breathing Apparatus. It’s a bit of a mouthful, so you can see why they shortened it. We’ll stick with SCUBA for the rest of this episode.
There is a theory of human evolution that says that all life on land once came from the sea. It probably makes sense that ever since people have walked the earth, they’ve been looking for ways to kind of go back there and discover all the mysteries of the ocean we’ve been missing out on by becoming land-lubbers.
The ocean has been a source of food for people all over the world for thousands of years. Do you have a favourite seafood dish? Prawn, Lobster, crab or maybe your humble fish and chips. Yum Yum.
But the oceans have also supplied us with many wonderful and amazing things that we have desired to make our lives better. A very early example of this is a sea sponge. Seriously, Italian and Greek divers would risk their lives to collect this very desired item.
Hang on. I’ve got an interesting fun fact for you… Did you know that sea sponges are actually animals? Honestly, they are carnivores and can live up to 2,300 years! Wow. The world really is a mysterious place. I wonder how they do poos…
Anyway, as far back as 2,500 years ago, divers from Italy and Greece would go right down to the sea bed and collect these precious sea sponges. I’m pretty sure you can guess what they did with these sponges because we still sort of use them the same way today. People would use these sponges to wash their bodies. But there was a problem. You see, the divers realised that the deeper they went, the softer the sponges.
So what’s the problem you might be wondering. Well, at the time these brave divers would hold their breath in order to reach the ocean floor. The best of them could hold their breath for up to five minutes, but this still wasn’t very long and didn’t allow them to go particularly deep.
There’s a beautiful phrase that you might have heard. “Necessity is the mother of invention” It means that when you’ve got a problem that’s when you’re most likely to come up with a great idea.
And that’s what happened here. Someone invented the first diving bell two and a half thousand years ago to help divers stay under water for longer. We know this because an Ancient Philosopher called Aristotle recorded details about how the bell worked. Basically it was a wooden box that would be lowered carefully into the water, trapping a pocket of air inside it. Divers could then pop their heads into the bell to take a new breath before continuing with their work under water.
If you want to do a simulation of how this worked, head to our web site for some simple instructions. But make sure an adult is supervising at all times. As you’ll hear, the evolution of SCUBA is not without its dangers.
Truthfully, a wooden box trapping air so a diver can last longer under the water isn’t really SCUBA in the true “Self-Contained Underwater Breathing Apparatus”. It is however the first record of humans seeking to extend their time exploring the ocean by bringing an air supply under the surface with them. Previously humans would use reeds as straws and such.
The diving bell was used and improved over a period of more than 1,000 years. A significant improvement included pumping fresh air into the bell from the surface. But further innovation was desired and there was great interest in creating a source of air that could travel continuously with the diver.
One of the earliest known designs for a diving suit with an air supply was created by none other than the famous inventor and artist, Leonardo Da Vinci. I’m sure you’ve heard of Leonardo Da Vinci.. a genius of the ages, his talents seemed to have known no bounds from art through to scientific enquiry and mathematics.
About 500 years ago Da Vinici was working in Venice – a city surrounded by water. During his stay in Venice, they came under attack from enemy ships. His idea was to allow divers to secretly sneak up and attack the enemy ships. Da Vinci designed a leather diving suit with a bag-like mask that would go over the diver’s head. Attached to the mask around the nose area were two cane tubes that led up to a cork diving bell floating on the surface. Unfortunately his creation was never made, like many of the creations he dreamed up.
One of the first known diving suits to actually be made was created in 1602 by a Spanish military engineer Jerónimo de Ayanz y Beaumont. Unfortunately, there isn’t much known about the design besides the fact that it was demonstrated to the Spanish King who was reportedly very pleased to be able to use it for the salvage of ship parts when they had been sunk.
This desire to salvage “sunken treasures” became a key motivator for the next wave of evolution. A need to reclaim valuable parts of ships, as well as the precious cargo, from the bottom of the ocean ended up motivating Englishman and inventor John Lethbridge. He constructed a “diving suit” in 1715. The suit was like a wooden barrel with two holes for the diver’s arms, sealed with leather cuffs and with a viewport of thick glass. Phew… I’m getting claustrophobic thinking about this suit, but it actually worked.
Mr Lethbridge became a very rich man by using his suit to dive down to ship wrecks and salvage the treasures trapped within them. Just imagine….
So far all of the diving equipment we’ve talked about has relied on very limited pockets of air, like those trapped in diving bells or air being supplied to the diver via tubes from the surface of the water. While these were great advancements from the first forays, they limited either the time that could be spent under water or the depth that a diver could reach. So new challenge… inventors turned their minds to trying to create a greater supply of air that divers could take with them under the water.
Now, this is when we must remind you that not all innovation is sunshine and lollypops. When inventors push the boundary of what can be, sometimes they get pushed back with upsetting consequences. The innovators that had turned their minds to find ways to create true underwater freedom for divers, well sometimes bad things happened. We’re going to tell you about a couple of the less successful inventors as a warning. A warning that you should always ALWAYS test your own inventions properly before relying on them to save your life.
In 1772, French inventor, SieurFreminet invented a device that recycled the exhaled air from inside of the barrel. This was special because it’s an example of the first real self-contained air device. Did you know .. While you breath in oxygen, you actually breath out carbon dioxide. And too much carbon dioxide and not enough oxygen is not good for humans. Unfortunately for Freminet, he didn’t really think about, or know about, the fact that you can’t rebreathe your own air for very long and he died from lack of oxygen after being in his own device for twenty minutes.
Thankfully other people were more sensible and by the end of the nineteenth century, two basic templates for scuba had been invented. There was open-circuit scuba where the diver’s old air went directly into the water, and closed-circuit scuba where the diver’s expelled air – carbon dioxide – was filtered and able to be used again for breathing.
The first commercially practical closed-circuit scuba was designed and built by the diving engineer Henry Fleuss in 1878. His equipment included a rubber mask connected by a tube to a bag. Air was supplied into the bag from a copper tank and divers could stay beneath the surface exploring or gathering treasure for up to three hours. This was a great advancement in the evolution of SCUBA, but it led to a new problem being discovered. You see, when we breath oxygen, we also breath in a chemical called nitrogen. Usually your body absorbs just the oxygen, however when you’re diving and you get deeper underwater, the nitrogen starts to be absorbed by your body too. And if you come up out of the water too quickly, the nitrogen causes bubbles to form in your blood. And that is not good. We now know that it’s important to take your time as you come up out of the deep ocean, but this is something Fleuss did not know. Fleuss died while using his own invention from what we now know is called the bends.
Unlike some innovations that completely halt due to the World Wars, the biggest innovations in scuba diving gear actually came about during the first and second world wars.
You see, in Paris during World War I, the Germans took all of the French petrol. An engineer called Emile Gagnan invented a demand regulator that would feed cooking gas to a car’s carburettor in the exact amount needed. This invention formed the basis of a mechanism that managed the flow of air from an air tank to a diver so that the oxygen wasn’t wasted.
Captain Yves Le Prieur was an adventurous fellow. He was the first French person to earn a black belt in Judo, designed various military weaponry and in 1925 he took Gagnan’s demand valve, added it to a high pressure air tank and became the first person to perfect an open-circuit, compressed-air device. He went on to co-found the world’s first scuba diving club.
But there was a problem.
The continuous flow of air meant that the air in the tanks ran out quickly.
Jacques-Yves Cousteau dreamed of becoming a pilot in the French NAVY, however an automobile accident in 1935 ended this dream. A year later, while still recovering, he borrowed a pair of goggles and experienced his first freedive in the Meditteranean. And he was hooked. The pioneer of marine conservation was born.
In June 1943, during World War II, on a small beach of the French Riviera, Jacques-Yves Cousteau, wearing rubber fins, shouldered a new, completely autonomous set of diving equipment.
Cousteau had modified the regulator that had been adapted from Captain Prieur’s invention and created the Aqua-Lung.
In 1966, Cousteau brought together his best divers, engineers and designers to create sophisticated equipment they called streamlined scuba. This new equipment reduced how tired divers became and that in turn reduced their air consumption. His innovations allowed divers to move about more quickly and for a longer time.
And here innovation of scuba seemed to have paused.
It was quite a while after Cousteau made these breakthroughs that there were any significant developments in basic scuba gear.
Over 20 years later, In 1987, the Newtsuit was developed by a Canadian engineer Phil Nuytten. The suit was made to be like “a submarine you can wear” and allowed divers to go to depths of 300 metres under water. The suit was made of aluminium but was flexible in the arms and legs so that divers could move about. It was initially used for ship salvage missions but also opened the ocean to scientific exploration in ways that were previously impossible. Since that time the suit has been adapted specifically to support marine research.
What will the future of scuba development bring to society? What mysteries of the ocean will be revealed as our technology increases and we discover more about our planet and its many oceans?
Even though scuba innovation seems to have slowed down, it has by no means stopped. Now would be a good time to hit pause and speak to the people around you about how you would innovate scuba gear so that diving and discovery in our oceans could become safer and better.
So, what did you come up with? Perhaps underwater drones to assist divers? Or maybe better diving suits? Honestly, my first thought was hoping for the discovery of Gillyweed like in Harry Potter! Now that was true underwater freedom.
Scuba gear has allowed and will continue to allow, many people incredible access into the ocean. From people who dive for pleasure to treasure hunters to researchers, scuba suits have opened up a new world of opportunities.
And with these new opportunities comes a great deal of risk.
Take a moment and think back to how society started our exploration into the ocean…. It was in search of the softest sea sponges which could only be found at the deeper levels. It was in search of the mysteries which could improve upon our life.
And as the quality of diving gear evolves and improves, scientists are inspired to turn to the sea to find more ways to improve our life, for new sources of potential medications.
What the Greek and Italian’s were doing with the sea sponges would now, in a way, be called bioprospecting. But modern bioprospecting is so much more than this. Since the 1990s Bioprospecting has involved looking to nature to give us ideas to improve life. Bioprospecting on land is well advanced, but as scuba has improved, bioprospecting in the ocean has been able to go deeper.
This in itself is the problem. This is part of the crisis facing our precious oceans.
Although marine bioprospecting holds incredible possibilities for treatments for illnesses that have been untreatable or poorly treated previously, exploiting our natural resources for medical purposes raises some issues around sustainability.
Yes, exploiting the ocean resources. Because with every dive the potential to upset the precious balance in the oceans is placed in jeopardy.
What a dilly of a pickle. On one hand our very presence in the ocean is causing it to deteriorate. But the mysteries and potential for improving human life by marine bioprospecting is just too strong a siren call.
So what can we do? Should we even keep innovating scuba equipment?
We spoke to Dr Kirsten Benkendorff
Dr Bekendorf said that one of the problems included the fact that if scientists find that they can create new medicines from certain marine animals, they need to collect and kill those animals to extract what they require. This can become problematic if the species they need is one that is rare, endangered or under threat already. Not only could scientists be potentially contributing to further endangerment of the species but also they frequently just don’t know enough about the flow on effects to other organisms in the eco-systems of significantly reducing the numbers of one creature.
Thankfully, scientists are a pretty ethical bunch of people. So, lots of them got together and came up with some ways to reduce the impact of bioprospecting.
One way forward is to only ever take a small percentage of marine life from any particular population, making sure that there were plenty of animals left to breed and re-populate.
Another is try, where possible, to make synthetic versions of the useful chemicals that they find in the animals. This means that they try to copy what occurs naturally using chemicals in a lab.
And finally, another option includes farming the creatures outside their habitats so that the natural populations don’t need to be disturbed.
The continual evolution of scuba equipment will bring many wonderful improvements to human life. And if all divers, be they treasure hunters, scientists or pleasure seekers, ensure they respect the fragility of our oceans and follow the guidelines that were agreed, the ocean and its creatures will continue to be there for the innovators/people of tomorrow.
If you want to make a miniature version of a diving bell, get a parent’s permission to fill a sink with water and then get a glass and a piece of paper. Secure the paper to the bottom of the glass with bluetak or playdough.
Turn the glass upside down and lower it, opening first into the water. Push it straight down and don’t tip the glass sideways at all.
Pull the glass straight up and remove the paper. It should be dry. This is because a pocket of air was trapped in the glass as you lowered it into the water and the pressure from the air kept the water out. This was the same principle used to create diving bells!
This episode was researched and written by Rachel Brittliff. It was edited by Melanie De Gioia.
It was narrated by Rachel Brittliff & Melanie De Gioia.
Editing and Music design was by Melanie De Gioia.
Music was licensed from Audio Jungle/Envato
We would like to extend our special thanks to Dr Kirsten Benkendorff, Professor of Marine Science at Southern Cross University who generously shared her time and expertise to help us put together this episode.
We would also like to thank Innovation NSW for their generous sponsorship which enabled us to make this special season of Idea Evolution.
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Through the entertaining story telling of everyday items, we will show how a single item has evolved society, inspire families to consider their impact on the environment and guide future innovators to put the planet first.