II. AN ENCOUNTER WITH A CHARACTER

III. THE PROFESSOR'S DILEMMA

IV. "WHERE IS HE?"

V. CHESTER CHADWICK--INVENTOR

VI. THE RADIO TELEPHONE

VII. THE GREAT TEST

VIII. TALKING THROUGH SPACE

IX. THE BOYS FACE TROUBLE

X. AN INVOLUNTARY AËRONAUT

XI. BY THE ROADSIDE

XII. MAKING ENEMIES

XIII. THE LEADEN TUBE

XIV. IN THE HOSPITAL

XV. A TALE OF THE COLORADO

XVI. ZEB CUMMINGS