mercurialist

from The Collaborative International Dictionary of English v.0.48

Mercurialist \Mer*cu"ri*al*ist\, n.
   1. One under the influence of Mercury; one resembling Mercury
      in character.
      [1913 Webster]

   2. (Med.) A physician who uses much mercury, in any of its
      forms, in his practice.
      [1913 Webster]