The contents of the present volume are meant as a plea for the greater spirit of tolerance with regard to the aspirations and activities of those who do not conform to our own self-opinionated standards of mentality; for the individuals whose "abnormalities" about to be described have been among the "great ones of the earth." Contents: tyrants and despots; crusades; witch mania and superstition; epidemic manias and almanacs; alchemists; bedlam; visionaries; peculiarities of men of genius; the remedy.