“20000 Leagues Under the Sea” Part1 Ch09

Question 1: How much oxygen does a typical person consume in one hour?  Is the following quote in chapter 9 realistic in light of modern knowledge?:

“The heavy air seemed to oppress my lungs.  Although the cell was large, we had evidently consumed a great part of the oxygen that it contained.   Indeed, each man consumes, in one hour, the oxygen contained in more than 176 pints of air, and this air, charged (as then) with a nearly equal quantity of carbonic acid, becomes unbreathable.”

Answer:In Volume 12 “Man Re-enters the Sea” of the series “The Ocean World of Jacques Cousteau” copyright 1975 by Jacques-Yves Cousteau published by The Danbury Press it discusses human oxygen needs:

pg75-Human lungs need only about a quart of oxygen per minute, regardless of depth;


Question 2: How did the Nautilus replenish its supply of fresh air.  How do modern nuclear submarines  accomplish this without having to resurface?  Have any submarine vessels used the chemical method described in the following quote from chapter 9:

 

“It became necessary to renew the atmosphere of our prison, and no doubt the whole in the submarine boat.  That gave rise to a question in my mind.  How would the commander of this floating dwelling-place proceed?  Would he obtain air by chemical means, in getting by heat the oxygen contained in chlorate of potash, and in absorbing carbonic acid by caustic potash?”

Answer 2:In Volume 12 “Man Re-enters the Sea” of the series “The Ocean World of Jacques Cousteau” copyright 1975 by Jacques-Yves Cousteau published by The Danbury Press it discusses the numerous aspects of obtaining air to breathe in an underwater environment.  The challenge of respiration is much different depending on the gas pressures involved.  As long as one is inside a submarine vessel where the air pressure is maintained at near atmospheric pressure, breathing pure oxygen is ok. Here are some quotes surrounding these issues:

pg 96: Oxygen is the only gas really necessary for human life, but breathing pure oxygen can cause problems.  For divers, the danger is very real, and it can become extremely hazardous to breathe pure oxygen at depths much greater than 20 feet.  Breathed at high pressure, oxygen can cause sudden convulsions involving the central nervous system, while oxygen at moderate pressure breathed for long periods of time can irritate and damage lung tissue, an effect that had been foreseen by Joseph Priestley and Antoine Lavoisier as long ago as the eighteenth century.

pg. 134 Respiration is always effected through membranes: the natural ones that constitute the walls of our lung alveoli and that separate air from blood; those of the capillary vessels that keep apart the blood from the tissues they irrigate; and in the case of fish, the membranes that coat the gills and separate blood from the seawater that bathes them. 

Such live membranes are permeable to gases and are penetrated easily by their molecules, but contain liquids.  Man today knows how to manufacture them; among artificial membranes are “silicone films” about five ten-thousandths of an inch thick, which were tested by W.L. Robb in 1964.  These membranes are used specifically in such medical aids as artificial kidneys and it was quite a natural progression to next test them for underwater respiration.

If a tight enclosure made of this material contains a small animal such as a hamster, the animal will be able to breathe normally, as oxygen diffuses through the walls to replace the quantity that is used up, and the carbon dioxide is eliminated in the same way.  If such a “cage” is completely submerged in the water of an aquarium, it will carry on functioning normally.  The watertight membrane keeps the enclosure dry and the exchanges of gases are maintained with the atmosphere, because gases also diffuse into the water.  The surface of the sea or of a river thus functions as an immaterial membrane. This is moreover almost exactly what happens in an enclosed cave through which an underground river flows. Speleologists know very well that “wherever there is running water, there is breathable air; any excess of carbon dioxide is dissolved and eliminated.”

For all these reasons, the partial pressure of each gas inside the “membrane cage” is identical to that of the same gases dissolved in the surrounding aquarium water and also the same as in the atmosphere.  The cage can contain only air at atmospheric pressure.  If any gases other than oxygen and nitrogen were introduced into it, they would escape to the atmosphere, and would be progressively replaced by air.

Pressure inside the enclosure being that of one atmosphere, the membrane walls must withstand the hydrostatic pressure of the surrounding water, an easy task in an aquarium, but positively impossible at any diving depth.  Any conceivable wall construction material cannot at the same time have the required mechanical strength and porosity.

On the other hand, it is possible to regenerate an enclosure at atmospheric pressure (such as a submarine, not a habitat) with seawater. The seawater is introduced in the enclosure, brought down to atmospheric pressure and sprayed in a “gas exchanger”; the water used is then ejected by a pump.  At least a hundred gallons of water are necessary to extract about one quart of oxygen by this method.  Regeneration of air by water spray gas exchangers has been proposed for military submarines; it requires great amounts of energy and it introduces a high degree of humidity into the submarine.  This method of regeneration has yet to be used.

One can indeed absorb carbon dioxide from the air with caustic potash, also known as Potassium Hydroxide, KOH.  See the following websites: 

http://chemicalland21.com/industrialchem/inorganic/KOH.htm

http://www.newton.dep.anl.gov/askasci/chem03/chem03329.htm

One can indeed generate oxygen using chlorate of potash, also known as Potassium Chlorate, KClO3.  See the following website: http://chemicalland21.com/industrialchem/inorganic/POTASSIUM%20CHLORATE.htm

Question 3: How is one’s sense of time changed in the absence of such clues as sunrise and sunset?  Are there biological rhythms that require such clues to stay in synch?  How long can biological rhythms continue in the absence of external time indicators?  Does this pose a  health risk to submarines that stay submerged for months?

Question 4: In the absence of sensory stimulus how long can persons remain sane?

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