In this gripping action-adventure tale geared for younger audiences, long-time chums Mark and Jack are living as the house guests of the brilliant inventor Prof

"Five Thousand Miles Underground" by Roy Rockwood is an action-packed story for young teens. The professor built an amazing machine with the ability to fly and

A cruise to the center of the earth through an immense hole found in an island in the ocean.

Roy Rockwood was a house pseudonym used by the Stratemeyer Syndicate for boy's adventure books. Edward Stratemeyer had earlier used the pseudonym "Roy Rockwood"