“They had a pretty good start of you,” said John Slater, the owner of the motor-boat.  “Maybe they are up to Nyack or Haverstraw by this time.”

“Well, all we can do is to keep on and watch out,” said Tom, with a sigh.  His disposition, for fun seemed to have entirely left him.

Another half hour went by, and they came in sight of a number of lumber barges, all heavily loaded.  The barges were being towed by a big tug.

“I know the captain of that tug,” said John Slater.  “We might ask him about the schooner.”

“A good idea,” answered Dick.

They were soon close to the steam tug and the motor-boat owner waved his hand to the captain of the larger craft, who waved in return.

“I want to find a schooner named the Ellen Rodney!” shouted John Slater.  “Did you pass her, Captain Voss?”

“I did,” was the answer.  “She was opposite Nyack, heading in to shore.”

“Opposite Nyack!” exclaimed Dick, “How far is that from here?”

“Not more than two miles,” answered John Slater, as he turned his motor-boat up the river again.

“We ought to be able to catch them now!” cried Sam, his face brightening a bit.

“Wish we had the police along,” remarked Tom.  “Bringing those rascals to terms may not be as easy as you imagine.”

“I’ve got a gun on board,” said John Slater.  “A double-barreled shotgun I keep on hand to guard against river thieves.  I use it to go gunning with, too.”

“Good!  Better bring it out and let us look at it,” returned Dick.

The weapon was produced and found to be in good condition and loaded.  It was placed on one of the seats, an oilskin raincoat being thrown over it to hide it from view.

“We won’t use force unless it is necessary,” said Dick, grimly.

They soon came in sight of Nyack, but nothing that looked like the schooner came into view.

“Maybe they went further,” suggested Sam.  “Their turning in might have been a bluff—­ to throw us off the trail.”

“Or they may have sent a message ashore—­ maybe a message to Japson!” cried Dick.

“Of course they would want to put him on guard—­ and put those at the offices on guard, too,” murmured Tom.

They continued on up the river, with their eyes ever on the alert.  It was now growing late in the afternoon and the sky was clouded, as if a storm was coming.

“Look!” cried Dick, suddenly, and he pointed ahead and to the right.

“The schooner, sure enough!” said Tom.  “And see, a rowboat is alongside!”

“Maybe we are just in time,” added Sam.  “I hope so.”

Without delay, the motor-boat was headed in the direction of the Ellen Rodney.  As they drew closer they saw but one man on the deck of the schooner,—­ a burly fellow who looked like a sailor.

“Schooner ahoy!” shouted Dick, as they ran alongside.

“Ahoy, the motor-boat!” cried the burly man, coming towards them.