GE0013@SIUCVMB.BITNET (Roy Miller) (02/09/90)
Index Number: 6624 Someone wanted to know "How do you tell which way is up" while SCUBA diving. If you are sighted and diving near the bottom, you can tell which way is "down" because you see coral, rocks, empty beer cans, and so forth on the bottom. When you are diving and the bottom is not visible, there is only one sure method of telling "up" from "down." The air that you expell from your lungs only goes one way -- and that is "up" toward the surface of the water (because of pressure differences). If you are a sighted person you can see which way your air bubbles are going and you know that they are going "up." If you were a blind person, you could simply move your hand around your regulator exhaust port and feel which way the bubbles were going -- and that would be "up."