fore the month is up. If we are not, go back to Tampico."
"Si, senor," answered the contractor, bowing mockingly.
Tom turned the lever that sent more gas into the bag. The balloon shot up. The young gold-seeker was about to throw on the motor, when Delazes waved his hand to the little party.
"Bon voyage!" he called. "I hope you will find the city of gold!"
"Bless my soul!" cried Mr. Damon. "He knows our secret!"
"He's only guessing at it," replied Tom calmly. "He's welcome to follow us—if he can. "
Up shot the aircraft, the propellers whirling around like blades of light. Up and up, higher and higher, and then forward, while down below the Mexicans yelled and swung their hats.
Straight for the north Tom headed his craft, so as to throw the eagerly watching ones off the track. He intended to circle around and go west when out of sight.
And then the very thing Tom had predicted came to pass. The balloon was scarcely half a mile high when, as the young inventor looked down, he uttered a cry.
"See!" he said. "They're breaking camp to follow us."
