Theis book is a reference book. "Ask Mary Baker Eddy" provides a list of all the marginal headings that occur within the Christian Science textbook, Science and Health with Key to the Scriptures by Mary Baker Eddy. If you want to know what Mary Baker Eddy was thinking on a certain subject, all you need to do is, ask. You have more than 1,700 prepared questions to choose from. The marginal headings are a type of paragraph headings within the pages. They describe what a certain paragraph is focused on. In earlier editions of the textbook, various types of indexes of the marginal headings were appended to the textbook. In modern editions, probably after 1932, the marginal headings were no longer indexed. In some cases, an index of words was added, as a type of concordance. However, in most cases a single word is insufficient to describe a specific thought or subject. The subheadings, however, are ideally suited to illustrate the point that Mary Baker Eddy is making in a paragraph or groups of paragraphs. I, personally, find the subheadings fascinating, and highly useful as a quick reference for finding Mary Baker Eddy's answers to specific subjects. In preparing the index, I dropped the convention to list the headings alphabetically sorted. I simply list them in the sequence in which they appear in the textbook, prefixed with the chapter numbers and page numbers. In addition, I have also created an index of the headers of the testimonies of healing in the chapter "Fruitage" of the textbook.