"I--er--I don't have to."

"Yes, you do. If you don't----" Dave ended by walking over to a barrel and filling the syringe with the spraying fluid.

"Hi! don't you douse me with that!" yelled the other youth in alarm.

Then he started to run away, but the senator's son caught him by one arm and Phil caught him by the other.

"You've got no right to hold me!"

"Well, we'll take the right," said Roger, calmly. "Now, Nat, do as Dave told you."

There was no help for it, and with very bad grace the money-lender's son drew from his pocket a silk handkerchief and removed what he could of the fluid from Caspar Potts's clothing. Many spots remained.

"I am afraid the suit is ruined," said the aged professor, sorrowfully.

"Anyway, it will need a thorough cleaning."

"If it is ruined, Nat can pay for it," said Dave, firmly.

"I'll pay for nothing!" grumbled the boy who had done the mischief. He was short of spending-money, and knew how hard it was to get an extra dollar from his parent.

"He certainly ought to pay for it," said Caspar Potts. "Some men would have him locked up for what he has done."

"Humph! Don't talk foolish! It was only a little fun!" grumbled Nat. "I didn't mean any harm. You can easily get those spots out of your clothes."

"Did he do anything else to you?" asked Dave of the professor.

"Yes, he plagued me a good deal, and he shoved me down in the cow-yard,"

was the reply. "I was hoping some one would come to drive him away. I said I'd have the law on him, but he laughed at me, and said n.o.body else was around and his word was as good as mine."

"If that isn't Nat to a T!" murmured the senator's son. "Doing the sneak act every time!"

"Well, we are witnesses against him," put in Phil. He looked at Dave and suddenly began to grin. "Oh, but this is great!" he cried.

"What's struck you?" queried Dave.

"Oh, nothing, only I reckon we've got a good hold on Mr. Aaron Poole now--in case he tries to make a complaint against you."

"To be sure we have!" burst out Roger. "He won't dare to do it--after he knows what Professor Potts can do."

"What are you talking about?" demanded Nat, curiously. "Is my father going to make a complaint against Dave? What is it for?"

"Maybe you'll learn later--and maybe you won't," answered the senator's son. "But if you see your father you had better tell him to call it off as far as Dave is concerned--if he wants to save you."

"Then you've had trouble, eh?"

"No worse than this--if as bad."

"Humph! In that case my father won't believe what you say about me!"

cried Nat, cunningly. And then of a sudden he leaped back, turned, and ran around a corner of the barn at top speed. He made for the road, and was soon hidden from view by trees and bushes. Phil and Roger attempted to catch him, but Dave called them back.

"No use in doing that," said Dave. "Let him go. It will be time enough to say more when Mr. Poole makes his complaint."

The three youths a.s.sisted Caspar Potts in rearranging his toilet, and in the meantime the aged professor told the lads the details of his trouble with Nat. The money-lender's son had certainly acted in a despicable manner, and he deserved to be punished.

"I will leave the matter to Mr. Wadsworth, and to your father and your uncle," said Professor Potts to Dave. "They will know better what to do than I."

On the way back to the Wadsworth mansion the boys told of the pistol incident and the professor became much interested. He agreed with Phil and Roger that Nat's doings were much worse.

Dave's father and his uncle had returned, and the youth went straight to them with his tale. Then Mr. Wadsworth came in and was likewise told.

All the men were also informed of what had happened to Caspar Potts.

"I think I see a way of clearing this matter up--if Mr. Poole attempts to act against Dave," said Mr. Wadsworth. And then he had a long talk with Professor Potts.

The folks at the mansion had just finished dinner when visitors were announced. They proved to be Aaron Poole and an officer of the law, brought along to arrest Dave.

"I think you had better let me engineer this affair," said Mr.

Wadsworth, and so it was agreed. He entered the reception room and shook hands formally with Aaron Poole.

"I came to get Dave Porter," said the money-lender, stiffly. "I am going to have him locked up."

"Mr. Poole, will you kindly step into the library with me?" answered Mr.

Wadsworth.

"What for?"

"I wish to have a little conversation with you."

"It won't do any good. I'm going to have that Porter boy arrested, and that is all there is to it."

"I wished to see you about your son, Nat. Do you know that he stands in danger of arrest?"

"Arrest! Nat?" queried the money-lender, and the officer of the law looked at the rich manufacturer with interest.

"Yes. Come into the library, please."

"Want me?" asked the officer.

"No," returned Mr. Wadsworth, shortly, and the man settled back in his chair, his face showing his disappointment.

Once in the library the manufacturer shut the door with care. He motioned his visitor to a chair. But Aaron Poole was too impatient to sit down.

"Now, what's this about my son, Nat?" growled the money-lender.

"I'll tell you," was Mr. Wadsworth's reply, and he related what had occurred at the old Potts place.

"You expect me to believe this?" snarled Aaron Poole.

"Believe it or not, it is the truth, and I have the three boys to prove it, and likewise Professor Potts's ruined suit of clothing. Now,"

continued the manufacturer, "I know all about your charge against Dave.

I'll not say that he wasn't careless, because he was. But he meant no harm, and it is going too far to have him arrested. It would be much fairer for Professor Potts to have your son locked up, and make you pay for the suit of clothing in the bargain. Now, the professor thinks a great deal of Dave, and he is willing to drop his complaint against Nat if you'll drop your complaint against Dave."