Abstract
This paper has been written with the object of clarifying a much-misunderstood situation. While the conclusions arrived at represent the author’s own deductions from current accomplishments, they are based on known facts and data, and other authorities are quoted extensively in order to present unbiased views from engineers who have no direct interest in the production of any particular type of engine and to avoid the impression of a one-man idea. Where opportunity has permitted it, reliable data have been quoted; where not so permissible, data have been omitted; but the author will gladly corroborate any statement or quotation which is thought by others to be doubtful or not sufficiently substantiated. It is suggested that the bibliography appended to the paper be carefully consulted in order that the scope of this effort may be fully digested. In substance, the paper should be considered a compendium of practically all that has been accomplished to date in this line which is, in the author’s opinion, worthy of note.
