What does the word mercurial mean?

Usage examples for mercurial

  1. Such was the legend attached to Tapton Everard, and such the story which the lively Caroline Ingoldsby detailed to her equally mercurial cousin, Charles Seaforth, lieutenant in the Hon. – Humorous Ghost Stories by Dorothy Scarborough
  2. The time more usually required in developing the image over the mercurial vapors, is about two minutes, and the temperature is raised to a point necessary to produce the desired effect in that time. – American Handbook of the Daguerrotype by Samuel D. Humphrey
  3. And Garry, who had been trying to marry Peggy for a year and was by no means as uncertain and mercurial in his affections as Kenny would have him believe, stared with eyes intelligent and reminiscent. – Kenny by Leona Dalrymple