Decompression (diving) but in later experiments signs of what was later to become known as decompression sickness were observed. Later, when technological advances allowed the use of pressurization of mines and caissons to exclude water ingress, miners were observed to present symptoms of what would become known as caisson disease, compressed air illness, the bends, and decompression sickness. Once it was recognized that the symptoms were caused by gas bubbles, and that re-compression could relieve the symptoms, Paul Bert showed in 1878 that decompression sickness is caused by nitrogen bubbles released from tissues and blood during or after decompression, and showed the
SS Edmund Fitzgerald can in "Edmund Fitzgerald"s pilothouse. That same year, Terrence Tysall and Mike Zee set multiple records when they used trimix gas to scuba dive to "Edmund Fitzgerald". The pair are the only people known to have touched the "Edmund Fitzgerald" wreck. They also set records for the deepest scuba dive on the Great Lakes and the deepest shipwreck dive, and were the first divers to reach "Edmund Fitzgerald" without the aid of a submersible. It took six minutes to reach the wreck, six minutes to survey it, and three hours to resurface to avoid decompression sickness, also known as "the