From previous experiences the writer has learned that many people, reading a novel such as “King Coal,” desire to be informed as to whether it is true to fact. They write to ask if the book is meant to be so taken; they ask for evidence to convince themselves and others. Having answered thousands of such letters in the course of his life, it seems to the author the part of common-sense to answer some of them in advance. “King Coal” is a picture of the life of the workers in unorganised labour-camps in many parts of America, The writer has avoided naming a definite place, for the reason that such conditions are to be found as far apart as West Virginia, Alabama, Michigan, Minnesota, and Colorado. Most of the details of his picture were gathered in the last-named state, which the writer visited on three occasions during and just after the great coal-strike of 1913-14. The book gives a true picture of conditions and events observed by him at this time. Practically all the characters are real persons, and every incident which has social significance is not merely a true incident, but a typical one. The life portrayed in “King Coal” is the life that is lived to-day by hundreds of thousands of men, women and children in this “land of the free.” The reader who wishes evidence may be accommodated. There was never a strike more investigated than the Colorado coal-strike. The material about it in the writer’s possession cannot be less than eight million words, the greater part of it sworn testimony taken under government supervision. There is, first, the report of the Congressional Committee, a government document of three thousand closely printed pages, about two million words; an equal amount of testimony given before the U. S. Commission on Industrial Relations, also a government document; a special report on the Colorado strike, prepared for the same commission, a book of 189 pages, supporting every contention of this story; about four hundred thousand words of testimony given before a committee appointed at the suggestion of the Governor of Colorado; a report made by the Rev. Henry A. Atkinson, who investigated the strike as representative of the Federal Council of the Churches of Christ in America, and of the Social Service Commission of the Congregational Churches; the report of an elaborate investigation by the Colorado state militia; the bulletins issued by both sides during the controversy; the testimony given at various coroners’ inquests; and, finally, articles by different writers to be found in the files of _Everybody’s Magazine_, the _Metropolitan Magazine_, the _Survey_, _Harper’s Weekly_, and _Collier’s Weekly_, all during the year 1914.