What happens when a plastic bucket is placed upright in a pool, as a function of how much water was in it? It's surprisingly complicated. A standard 10 qt, flat bottom bucket, density 1+ε, floated perfectly upright when empty, but leaned rapidly in proportion to the amount of added water, finally reaching a tipping point, where it sank. OtOH, it floats upright when lowered in nearly full to begin with, and eventually sinks with additional water. But when Neil tried it with a 5 gal bucket, density 1-ε, with nearly vertical sides, the rim stayed just above water at the tipping point, and it gradually righted with additional water. (And never quite sank due to its low density.) Both of these experiments were biased slightly toward tipping by the weight of the bails, but probably not significantly. The 10 qt experiment had a metal bail and needs to be repeated with more control. --rwg