"Stone and bone needles found in ancient tombs led Joseph Needham to speculate that acupuncture might have been carried out in the Shang dynasty.This being said, most historians now make a distinction between medical lancing (or bloodletting) and acupuncture in the narrower sense of using metal needles to attempt to treat illnesses by stimulating points along circulation channels ("meridians") in accordance with beliefs related to the circulation of "Qi".