This is a revision of Brünings' original work published in German in 1910. A considerable part of the former edition was taken up with a description of instruments that is no longer necessary; therefore this has been omitted and similar space devoted to important clinical material. The instruments used are illustrated and explained, the technic of the operation is described, and the difficulties that are liable to be encountered and the methods of overcoming them are clearly pointed out. The normal appearance and psysiologic action of the parts to be examined are carefully considered and the indications for, and dangers of bronchoscopy and esophagoscopy are discussed. An excellent chapter on treatment of various diseases has been added. The book is a most useful one that can be studied with profit by all those who essay to do tube work. The book is well illustrated and has an. excellent index.