Dear Straight Dope:
There's a phenomenon I'm curious about. We keep hearing that at the depth to which the Titanic sank (12,000 plus feet), the pressure is several hundred times that of surface and just about anything but bathescape (sp. wrong, I know, but not in my e-mail spell checker) Trieste will be crushed. Yet the debris field near the ship reveals lots of seemingly intact fragile objects ... bowls, etc. How can this be?
Russell Shaw, Portland, Oregon
Bathyscaph(e). The “bathy(s)” means “deep”; the “scaph(e)” comes from “skaphos,” “boat.” The resembance of the Greek to English “ship” and “skiff” is obvious.
The reason some items are unaffected by high pressure is that they are solid–the pressure simply squeezes them equally from all directions. This will make a solid object slightly smaller, but doesn’t cause any one part to move relative to the others, so nothing breaks. In contrast, porous things like wood can get horribly distorted as the air-filled cells are crushed, and hollow items like bottles or cans collapse. However, if the bottle or can is open and can fill with seawater, the pressure will be equalized and the container will survive the trip to the depths intact.
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