II. THE AIRSHIP BOYS ADRIFT
Or, Saved by an Aeroplane.
III. THE AIRSHIP BOYS DUE NORTH
Or, By Balloon to the Pole.
IV. THE AIRSHIP BOYS IN THE BARREN LANDS
Or, The Secret of the White Eskimos.
V. THE AIRSHIP BOYS IN FINANCE
Or, The Flight of the Flying Cow.
VI. THE AIRSHIP BOYS’ OCEAN FLYER
Or, New York to London In Twelve Hours.