Charles Darwin tired all sorts of quack treatments for his mysterious illness—most famously, hydropathy (or hydrotherapy as we refer to it nowadays). But, for a short while before he fell for the hydropathy craze, Darwin dabbled briefly with a more hi-tech treatment: galvanisation. In a letter to Joseph Dalton Hooker, he confessed:
You ask about my health: I have been unusually well for a week past, owing, I believe, to what sounds a great piece of quackery, viz twice a day passing a galvanic stream through my insides from a small-plate battery for half an hour.— I think it certainly has relieved some of my distressing symptoms
Darwin knew quackery when he smelt it, but he did not have the modern explanation of the placebo effect to fall back on to explain its apparent success.
See also: Darwin in Ilkley