(Work-in-progress) This page will be devoted to an article about Longevity Test setups. For the time-being, see also and Edward's Test Matrix page. This is a simple, primitive apparatus that has turned out to be extremely useful in evaluating both detergents and bubble juice. It consists of a plastic bottle whose bottom has been removed. The bottle's mouth is dipped in the solution to test, turned right-side up, and lowered into water. This allows one to compare bubble lifetimes (if adequate repetitions are performed) in a meaningful way.