My grandparents had those bubble lights. They used to hang them on the tree every Christmas. Back in the early 2000's some company made repro sets of these bubble lights. I bought two sets and used one set to augment my window decorations. If I can find them I might set them up this year. Also, if anyone has an old set it is possible to pry them open and replace the bulb within that provides the light to light the globe and the heat to boil the liquid. Old sets can be restored.