I A MYSTERIOUS DISAPPEARANCE II A BOLD STROKE REWARDED III THE MYSTERIOUS PHI BETA KI IV FOR HE IS A WHITE MAN'S DOG V CAST ADRIFT VI THE DREAD WHITE LINE VII THE BLUE ENVELOPE DISAPPEARS VIII THE VISIT TO THE CHUKCHES IX A CLOSE CALL X FINDING THE TRAIL XI "WITHOUT COMPASS OR GUIDE" XII "WHAT IS THAT?" XIII STRANGE DISCOVERIES XIV A LONESOME ISLAND XV TWO RED RIDING HOODS XVI A FORTUNATE DISCOVERY XVII OUT OF THE NIGHT XVIII A NEW PERIL XIX MYSTERIES EXPLAINED