Jacques Cousteau's book, The Silent World was written
in the late 40's. Chapter Two is titled, "Rapture of the Deep." In 1943,
Cousteau's friend, Frederic Dumas (known as "Didi") were trying to deep dive
in the Mediterranean Sea. They were in 240 feet of water. Didi was to descend
on a line to the greatest depth he could reach and then release his weight
belt and tie it on the line from the ship to the bottom. On page 30 of The
Silent World Didi describes the dive:
"'The light does not change color as it usually does
underneath a turbid surface. I cannot see clearly. Either the sun is going
down quickly or my eyes are weak. I reached the hundred foot knot. My body
doesn't feel weak by I keep panting. The damn rope doesn't hang straight.
It slants off into yellow soup. It slants more and more. I'm anxious about
that line, but I really feel wonderful. I have a queer feeling of the beatitude.
I am drunk and carefree. My ears buzz and my mouth tastes bitter. The current
staggers me as though I had to many drinks. "I forgotten Jacques and the
people in the boats. My eyes are tired. I lower on down, trying to think
about the bottom, but I can't. I'm going to sleep, but I can't fall asleep
in such dizziness. There's a little light around me. I reach for the next
knot and miss it. I reach again and tie my belt on it. Coming up is merry
as a bubble. Liberated from weights I pull of the rope and bound. The drunken
sensation vanishes. I'm sober and infuriated to have missed my goal. I pass
Jacques and hurry on up. I am told I was down seven minutes.' Didi's belt
was tied off two-hundred and ten feet down. This huisser attested it. No
independent diver had been deeper. Yet Dumas's subjective impression was
that he had been slightly under one hundred feet."
This was the first widely read description of the
intoxicating affect nitrogen has under pressure. The description, "Rapture
of the Deep" now is known as, "Nitrogen Narcosis" or "Inert Gas Narcosis".
There is a law among divers known as "Martini's Law."
It states: Every 50' of seawater equals 1 dry martini on an empty stomach.
Although it is a rough estimate, it would mean a diver at 200' is experiencing
intoxication from pressurized nitrogen equal to 4 martinis!
Many gases are intoxicating when mixed with 21% oxygen.
It is pressure-dependent. Also, the more a gas dissolves in fat the more
narcotic it is. Nitrous oxide has a narcotic affect at sea level, and that
is why you get "drunk" in the dentist's chair. Xenon dissolves in fat over
20 times better than nitrogen . It is far more narcotic and has been used
for anethesia. The gases neon and argon do not produce intoxication at 1
atmosphere but will do it under a pressure less than 100' of seawater, argon
having more potential than neon. Nitrogen is less intoxicating than neon.
Oxygen has a narcotic effect similar to nitrogen, so breathing nitrox does
not change the outcome. Helium requires a very great pressure (over 1,000
feet) to produce euphoria. A gas's solubility in oil and its atomic/molecular
weight are causative factors.
If you dive deep you will get "narced" because of nitrogen
narcosis. What happens to you depends on several factors. As with alcohol,
the reaction is due to personality, body size, fat content, mood, breathing
depth, activity, and what you are looking to do. If you are trying to get
narced, have an elevated CO2 level, are deep, and active the narcosis will
be pronounced. And, the narcotic affect may be more noticeable from one day
to the next keeping all the variables the same. It seems the more a diver
encounters nitrogen narcosis the better it is tolerated. Also, the amount
of narcosis reaches a maximum state in about 5 minutes at any given depth.
Reactions vary to this drunken state. One diver was trying
to break a depth record. A safety diver was observing from about 200'. The
diver was below 350'. The last thing the safety diver saw the other one do
was to take his mouthpiece out and try to hand it to a passing fish. Then
he sank into over 3000' of water. Photographers on the Andrea Doria (216'
deep) took fully 1 minute to insert a flashbulb in the flashholder. Just
as with booze, some divers get giddy, some get beligerant, some get crazy.
When a person is met for the first time is it possible to predict how the
will handle liquor? Is a diver able to predict what will happen when they
get narced for the first time?
To show the reader how variable the effects are, this
author was in St. Lucia and planned to go to 200' with an agreeable buddy.
The first day the bottom slope was not steep and it took a long time to go
deep. At 141' I started to feel the effects of narcosis. I was lightheaded
and had a slight buzz on. It was euphoric. I signaled my buddy to abort the
dive so we turned around and slowly made our way to the surface. My buddy
claimed to feel no intoxication. We decided to make the attempt again the
next day. This time the slope was steeper so we could go deep quickly. At
184' I felt no narcotic effect. All of a sudden my buddy turned around and
wanted to do a do-se-do with my arm. Needless to say we aborted the attempt
to go deeper.
If narcosis is encountered all the diver has to do is
go up in the water a short distance, often as little as 10', and it will
disappear without any trace or hangover. Remember, Dumas was "sober and