Right. Good. Thank you very much.
It's a buoyancy thang! I completely understand now. Sometimes all you need to solve a problem is the right word to put in the wikipedia search. In this case, "Archimedes".
Again, thanks.
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Assume I have an indestructible, impermeable, rigid globe (of a fictional metal, say) containing a complete vacuum, and I am able to change the size of the sphere at will. My globe and I are standing at...