Wednesday, February 4, 2015

Another Interesting View – Part II

Continuing with the last post, regarding the Lord’s instruction to cut a hole in the top and in the bottom of the Jaredite barges. For those still thinking that these two holes were in opposite sides of the barges, such as one on top of the barge, and one on the bottom, meaning along the keel (beneath the water line), we need to keep in mind what we are dealing with and the purpose of these two holes.
One-atmosphere submersibles: Left: Individual with an umbilical; Right: Diving Unit with tethers and umbilical. Both have oxygen fed from the surface
    First of all, a one-atmosphere submersible requires a system where its internal air can be replaced—in the modern era, this is generally by an umbilical while tethered to a support facility platform or surface vessel (a true submarine is fully autonomous and relies on its own ability to both provide fresh air—by adding oxygen to the existing air—and get rid of exhaled carbon dioxide—by scrubbers with soda lime, lithium hydroxide, or a similar compound that takes up CO2).
    Secondly, the holes in the Jaredite barges had to do with breathable air. To begin with, Jared expressed his concern about such breathable air when he said to the Lord, “And also we shall perish, for in them we cannot breathe, save it is the air which is in them; therefore we shall perish” (Ether 2:19). Even the brother of Jared clearly understood that air (oxygen) within the barges could not be replenished because of the tightly sealed or encased vessels, as the inside of the Baobab trees they had hollowed out to form the barges. He understood that air, over time, deceases its oxygen content (replaced by carbon dioxide) and causes asphyxiation.
    As an example, every year people are killed from nitrogen asphyxiation by breathing “air” that contains too little oxygen (U.S. Chemical Safety and Hazard Investigation Board Safety Bulletin #2003-10-B, June 2003). This is because 78 percent of the air we breathe is nitrogen gas, and therefore many people assume that breathing nitrogen is not harmful. However, nitrogen is safe to breathe only when mixed with the appropriate amount of oxygen.
    The other problem is that in a one-atmosphere vessel containing people and animals, normal air (nitrogen and oxygen) is quickly changed through breathing from its 0.036% content of carbon dioxide (CO2) to increasingly higher levels—air becomes mildly toxic to humans at 1% CO2; is still breathable at 3%, though only temporarily; but becomes poisonous when CO2 reaches 10%, the latter causing respiratory paralysis and death within minutes.
    As an example, in a one-hundred-cubic-foot space, where air is not replaced, and where CO2 reaches 3% of air content, one person at rest would have about 17 ½ hours before respiratory paralysis and death set in. In this case, headaches, increased breathing, difficulty in concentration, fatigue and clumsiness begins within six hours; and within 12 hours, impaired vision, and breathing rate 50% faster; and after 18 hours, extreme sluggishness, increased blood pressure, and severe headaches; and after 24 hours, permanent side effects occur, breathing four times faster than normal rate, choking and unconsciousness occurs.
    The point is, while there would be time to manage correcting the problem when one opening is closed, within a few hours, judgment and ability to correct the problem fades and becomes unlikely. Consequently, when the Lord said, “And if it be so that the water come in upon thee, behold, ye shall stop the hole, that ye may not perish in the flood…and when thou shalt suffer for air thou shalt unstop the hole and receive air” (Ether 2:20).
    In normal structures, including boats, houses, buildings, etc., wind-induced ventilation uses pressures generated on the structure by the wind, to drive air through openings. It is most commonly realized as cross-ventilation, where air enters on one side, and leaves on the opposite side, (though can also drive single sided ventilation, and vertical ventilation flows).
Cross ventilation (left) is the most economical and effective ventilation available, where one opening on one side and another opening on the other side ensures the transfer of air through induction (intake) and exhaust (exhaust or removal). This ventilation, of course, has three main purposes: 1) to maintain a minimum of air quality (breathable air); 2) to remove heat (transfer of air); and 3) to provide perceptible air movement to enhance thermal comfort (temperature regulation).
    Thus, one opening (hole) is needed for induction, to bring in fresh air, and one opening (hole) for exhaust, to remove overheated, and oxygen-depleted/carbon dioxide increased air. It is also important that the internal flow path of the air inside the structure (Jaredite vessels) is considered—as an example, the leeward interior (furthest from the induction point) will have air that has picked up heat and pollution (carbon dioxide increases). When there is no second opening, this builds up until the pressure inside the (airtight) structure stops any further induction.
    Consequently, when the brother of Jared asked about needing air they could breathe (Ether 2:19), he was inferring the need for air exchange or ventilation. The Lord’s response was scientifically right on—cut two holes, not just one. Thus, to create a vacuum for air flow (ventilation) you have to have pressure and two openings—one for the air to come in and a second opening for the air to leave. As cooler (outside) air enters, the hot (inside) air will be pulled out of the space, thus natural ventilation actually cools the space down as it whisks away stagnant hot air.
For effective air circulation and flow, the internal flow path inside the vessel had to be considered. Too large a hole and too much wind would enter, blowing like a gale through the vessel; too small of a hole, and not enough air exchange would take place. The more the opening area is distributed, the more likely it is that there would be a pressure difference between openings to drive the flow—small openings are better than larger ones. Also, consideration had to be given to control this air flow through the natural ergonomic design of the inside trunk walls
    In this case, both holes would need to be open at the same time to replenish the air inside the “air tight” vessel, since air cannot enter an enclosed space with only one opening because there would be no way for the trapped air inside to escape so it could be replaced with “new” or “fresh” air. This is why so-called “moon pools” can be open to the sea below the waterline of a ship (or even in underwater habitats, such as the Aquarius laboratory Reef Base in Key Largo, Florida), since the airtight pressure above the opening keeps water from rising. However, in such cases, as in the Jaredite barges, such openings in the hull (along the keel) would not allow any air entrance because of the air-tight chamber that is open to the sea.
Underwater laboratories, such as Skylab III uses a moon pool that is open to the inside of the vessel, which itself is airtight so no water can enter
    It should also be kept in mind that these barges were “pushed,” or as the scriptural record states: “and thus they were tossed upon the waves of the sea before the wind.” (Ether 6:5, emphasis mine), and “thus they were driven forth before the wind” (Ether 6:8, emphasis mine), meaning the wind was approaching the barges from the rear (stern, or “bottom”), and thus with the “bottom” hole open, the wind would be blowing directly into the barge, pass down its length, and exit out the “top” hole, creating perfect cross-ventilation with both holes open. But if the water from the “waves of the sea” because “of the mountain waves which broke upon them” and “the great and terrible tempests which were caused by the fierceness of the wind” caused that “the water should come in upon thee, behold, ye shall stop the hole, that ye may not perish in the flood” (Ether 2:20).
(See the next post, “Another Interesting View – Part III,” regarding these two holes stated in Ether 2:20 and their overall importance)

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