The pressure increases linearly with the depth and eventually the wall would become extremely difficult to construct.

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At that depth, the pressure of the rock overhead is just enough for liquid CO2 to be stable, if the temperature is low enough.

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That depth provides enough pressure to turn CO2 into what is known as a supercritical fluid, a form in which the stuff is more likely to stay put.

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The tiny compartment that the film-maker sits in is made from thick steel, which is able to resist the 1, 000 atmospheres of pressure he experienced at full ocean depth.

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Most gyms have a seated fly machine that uses the forearms as a pressure point to avoid all gripping, and the depth of the motion can be adjusted to reduce rotator cuff stress.

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But we have no depth to the squad, there is no pressure on the players.

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