The Caduceus of Hermes versus The Staff of Asclepius
The casual observer would probably not even notice that these are two distinct symbols. The Caduceus, the two-serpent staff associated with Hermes, the Greek mythological character, is often incorrectly associated with medicine and healing. They should be using the Staff of Asclepius. Here is a quick primer but you can read more on Maicar and on this page.
The Caduceus of Hermes
The link between the caduceus and medicine may have been attributed to a seventh century AD reference to alchemists being the sons of Hermes. Throughout history, the caduceus was incorrectly associated with medicine and healing. Even the US Army incorrectly used the symbol in 1902 for the medical corps. The caduceus is properly associated with alchemy which itself is associated with the occult rather than legitimate medicine and healing.
GHermes, incidentally, was associated with herding souls into the afterlife. How healthy is that?
The Staff of Asclepius
Asclepius, on the other hand, was an ancient Greek physician deified as the god of medicine. More like it, right? His staff has only one serpent wrapped around it. This symbol is correctly associated with medicine and healing. So before you start waving your ophidian-wrapped staff around, make sure you count the number of serpents first. You don’t want to embarrass yourself at your next alchemists convention.