Notes:
This digest-format early graphic novel is packaged like a paperback book rather than a comic book. There are no advertisements; the back cover describes the characters in the book; the inside covers are blank; the first interior page is a title page and the second a copyright statement page as in a typical book.
Historian Martin O'Hearn calls it the the "First (or Second) Modern Graphic Novel", but it depends on the definitions of "modern" and "graphic novel" one is using. (It is unknown whether this or Mansion of Evil (Gold Medal Books, 1950 Series) was released first)
Historian Hal Johnson calls it the "First American Graphic Novel", and his reasoning (and the earlier candidates he rejected) can be seen here: https://haljohnsonbooks.substack.com/p/what-is-the-first-american-graphic