I thought I had lost these somewhere along the way. Perhaps in our last move. With a sigh of relief, I recently unearthed them along with some beautiful French boxes of insect specimens. I was less concerned about the loss of the bugs because, while quite unusual and striking, they posed no safety threat. Not so for the hydrometers. Those big silvery bulbs at the ends contain mercury. And lots of it. I just happened to have finished reading a disturbing article about South America and how, as a result of the gold boom, mercury contamination has spread at astonishingly high levels in both air and water. So the question of what to do with these things is front of mind. Suggestions are welcome. I don’t mean to be glib, but poison aside, these are pretty amazing.