MIDNIGHT
THE SECRET OF THE CAVES -- When the boys reached the caves they came unexpectedly upon a queer old hermit . THE MYSTERY OF CABIN ISLAND -- A story of queer adventures on a rockbound island . THE GREAT AIRPORT MYSTERY -- The Hardy Boys solve the mystery of the disappearance of some valuable mail . WHAT HAPPENED AT MIDNIGHT -- The boys follow a trail that ends in a strange and exciting situation . WHILE THE CLOCK TICKED -- The Hardy Boys aid in vindicating a man who has been wrongly accused of a crime . FOOTPRINTS UNDER THE WINDOW -- The Smuggling of Chinese into this country is the basis of this story in which the boys find thrills and excitement aplenty . GROSSET & DUNLAP , Publishers , NEW YORK TED SCOTT FLYING STORIES By FRANKLIN W. DIXON Illustrated .