The lonely and mysterious swamp gave up its secret only after a series of terrifying events taxed Hal's courage and ability.
THE CLUE AT SKELETON ROCKS
In this new thriller Hal Keen finds mystery and adventure in and about a lonely lighthouse on Skeleton Rocks, off the Maine coast.
THE DOOM OF STARK HOUSE
Mystery and terror in an old house in the wilderness above Quebec where Hal Keen is the guest of a strange family.
GROSSET & DUNLAP, Publishers, NEW YORK
ADVENTURES in the UNKNOWN
By CARL H. CLAUDY
Weird! Mysterious! Incredible! Astounding!
Leap back a million years into the dark prehistoric ages. Speed through the dangers of outer space beyond the stratosphere at a thousand miles a minute. Meet the grotesque machine men of Mars. Break into the bounds of the Fourth Dimension. You will meet in these thrilling, fascinating stories many incredible beings and astounding sights that will stagger your imagination.
THE MYSTERY MEN OF MARS