The term emanotherapy is used here to include the treatment of widely differing pathologic conditions, except malignant conditions, with small amounts of radon in such forms as drinking water, baths and muds. This form of treatment is here referred to as emanotherapy in order to differentiate it from treatment in which radium salt is used. The author definitely emphasizes the fact that he refers only to treatment with radium emanation and never to treatment with radium salts. Furthermore, nothing in this book concerns itself with the application of radon in concentrated form, as it is used for local treatment of malignant diseases. Therefore, all objections which arise from the knowledge of the danger of repeated administration of radioactive salts are at once eliminated. The scope of the book is limited to the use of small amounts of radon in the different types of treatment already mentioned.
Since radon has a