Humans may now be able go deep inside the waters, as a US scientist has designed a scuba suit would allow us to breathe liquid like fish.
Arnold Lande, a retired American heart and lung surgeon, has patented a scuba suit that would allow a human to breathe "liquid air", a special solution that has been highly enriched with oxygen molecules.
"The first trick you would have to learn is overcoming the gag reflex," the
quoted Lande, a 79-year-old inventor from Missouri, as saying.
"But once that oxygenated liquid is inside your lungs it would feel just like breathing air," he said.
Lande envisages a scuba suit that would allow divers to inhale highly-oxygenated perfluorocarbons (PFCs) - a type of liquid that can dissolve enormous quantities of gas. The liquid would be contained in an enclosed helmet that would replace all the air in the lungs, nose and ear cavities.
The CO2 that would normally exit our body when we breathe out would be "scrubbed" from our blood by attaching a mechanical gill to the femoral vein in the leg.
Currently the only way divers can work for long spells in the deep is either from the safety of robotic vessels and submarines; or by using saturation diving, an incredibly complicated technique where divers have to be brought up to the surface in a pressurised container over a matter of weeks.
With saturation diving, the deepest anyone has gone is 701m. Using scuba equipment the record is 318m, set by the South African diver who took 14 minutes to descend and 12 hours to come back up to the surface.
The reason for these slow ascents is that the reliance on compressed gasses to breathe in water. Under the incredible pressure exerted by billions of tonnes of ocean, gasses like nitrogen and helium dissolve into our bloodstream, much like CO2 is dissolved in a soda bottle.
"The beauty of doing it all from a liquid is that you don''t have to use these highly compressed gasses in the lungs that are going to dissolve into the blood.
"You have a liquid that you can infuse just as much oxygen as you need," said Lande.
He added that using a cuirass, a ventilation device named after a piece of medieval armour, which compresses the diaphragm and makes it easier to breathe liquid.
The findings were presented to the first International Conference on Applied Bionics and Biomechanics in Venice.