This edition is based on a public-domain work by Fergus Hume.
The base text is believed to be in the public domain in the United States (95 years from publication, or life of the author plus 70 years). Public-domain status may vary by jurisdiction and depends on the author's death year and local copyright term rules.
Modern additions, formatting, cover design, notes, and metadata may have separate rights where stated.
Published by Nydus Foundation.
Released 2026-07-13.