This book is a collection of essays or sketches previously published in various periodicals. The "pathfinders" dealt with are: Galen, Aretaeus, Paracelsus, Servetus, Vesalius, Pare, Scheele, Cavendish, Hunter, Jenner, Laennec, Simpson, Semmelweis, Schleiden, Schwann and Darwin. The frontispiece is a representation in colors of the Semmelweis monument in Budapest, and there is an illustration of each of the persons whose life and work are sketched. As Abraham Jacobi says in his introduction, "the author's facts as related are absolutely correct," the style is animated, and to many the reading of these sketches should prove pleasant and profitable.