Dropping fast, the cream and green biplane roared down like an avenging bird. Ralph levelled off about twenty feet above the river and sped toward the amphibian. Tim saw something sticking over the side of the biplane. It looked like a gun but the distance was too great and the speed too fast to make sure.

The men aboard the amphibian were caught unawares. The big craft slowed down and seemed to hesitate as the pilot waited for orders from Sladek.

Ralph whipped the Jupiter over the amphibian and Tim saw the splatter of shot on the water. The biplane shot upward and around in a tight bank and came back at the clumsier plane, which again was showing signs of life.

The motors of the amphibian thundered mightily. The big ship shook its wings and lunged ahead, slithers of spray shooting out from its slide.

Overhead hummed the Jupiter and Tim could see now that Ralph was shooting at the larger plane. As the amphibian took off, Ralph circled over them and Tim saw his flying companion wave.

“Ralph will keep Sladek busy for a few minutes,” he told Ford. “We’d better get to Auburn as soon as possible.”

While Ralph in the Jupiter chased the slower amphibian all over the valley, Tim and Ford sped up the river as fast as the outboard motor could chug.

“That was a timely arrival on the part of your friend,” grinned Ford.

“It wasn’t altogether accidental,” replied Tim. “I was afraid of trouble and Ralph remained at Auburn with the ship all tuned up and ready to go at the slightest hint that I was in a jam.”

“He seems to be a mighty good flyer.”