The idea that stress or other emotional states influence health has been around for centuries. Lately, the scientific community seems to re-examining this concept and starting to investigate the potential physiologic pathways that may be activated by emotional states. This book from 1910, provides a discussion of research (mainly anecdotal) being done on this idea at the time. The main theme is that the use of suggestion (positive or negative) can influence mental and thus physical health. The author would agree with other modern authors who argue that positive mental states can induce positive health benefits. The author ultimately argues that such effects are due to suggestion (a placebo type effect), regardless of the manner in which the suggestion is presented.
Unlike another reviewer of this book, I do not feel that the author explores this topic in detail, but does provides several case illustrations, and basically restates his theme on more than one occasion. For more detail as to the views of the scientific community at that time toward the concept, I would refer those interested to George W. Crile (The Origin and Nature of the Emotions), or Daniel Tuke (Illustations of the Influence of the Mind upon the Body in Health and Disease - 1873). Tuke is cited often in this work, and actually predates it by more than 25 years. For other illustrative examples, William James would be of value (Principles of Psychology).

All ancient wisdom teachings have had healers who healed with powers not their own - this book discusses in detail how healing works on the mental, subconscious, spiritual and physical levels. Also how the "sick" person must partake in the healing for it to occur. A very good read on the subject.