I tried this as an experiment once, on the advice of someone else. Lavender is a wonderful painkiller. I had slipped and fallen on the ice, resulting in an extremely sore back, and I remember my Mother telling me, "How wonderful lavender was for muscle aches, if you can find some." She was unaware that Lavender could be found, as a bubble bath! She had lavender in her garden many years ago, and used that. A half hour soak in the tub, and no more pain. (Just don't fall asleep, in the tub!)