Back in 1998, I lugged about a ton of river rock, two hundred pounds at a time, up to the Life exhibit. They were a scenic component that I laid out one stone at a time in the very serene, oval, solid wood floor entrance to the Life exhibit. I remember arguing with Ly that we should epoxy the rocks in place. She didn't think it was necessary. I was more concerned about people kicking or throwing them.
Over time, kicking has been an issue. Throwing has not.
Neither one of us ever saw this coming:
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I'm glad we didn't glue the rocks down.