CHAPTER 16 _SUSPICION_
Everyone who witnessed the spectacular demonstration was awed by thesight of the flames rising above the lake. As they died away, ProfessorBettenridge, strutting a bit, walked back to his machine and covered itwith the canvas hood.
"Now are you satisfied?" he inquired triumphantly. "Is there anyone herewho doubts the remarkable possibilities of my invention?"
"It was a fine demonstration! Magnificent!" approved Mr. Johnson, fairlybeside himself with excitement. "I am convinced of the machine's worthand if we can agree upon terms I will write you a check tonight."
Professor Bettenridge's expression did not change, but the brief glancehe flashed his wife was not lost upon Penny or Salt.
"You understand, of course," he said smoothly, "that the Navy probablywill insist upon ultimate purchase of the machine even if I relinquishownership?"
"Certainly," agreed Mr. Johnson. "I should expect to make such a sale.The machine would have no practical use except in warfare."
Penny was tempted to ask the man if he considered it patriotic to try toobtain control of a machine in the hope of selling it to the governmentat a high profit to himself. But she wisely remained silent.
Salt, however, had a few pointed remarks to offer.
"How come," he observed, "that if this invention is so remarkable, theNavy hasn't already snapped it up?"
Professor Bettenridge froze him with a glance. "Young man," he saidcuttingly, "you evidently do not understand how government business isconducted. Negotiations take months to complete. My wife and I need cash,so for that reason, we are willing to sell the machine quickly."
"Yesterday I understood you to say that Navy men were ready to completethe deal," Penny interposed innocently. "Did they change their minds?"
"Certainly not!" Professor Bettenridge's dark eyes flashed, and only bygreat effort did he maintain control of his temper. "You understand thatwhile their recommendation would eventually be acted upon, a sale stillwould take many months to complete."
"Will your machine explode mines on land as well as in the water?" Saltinquired.
"Of course!"
"Then why not give us a land demonstration?"
"Us!" the professor mocked, his patience at an end. "Young man, you werenot invited here, and I might add that your presence irritates me! Areyou in any way associated with Mr. Johnson?"
"I am not."
"Then kindly do not inject yourself into our negotiations."
"The young man raises an interesting point," Mr. Johnson interposed,frowning thoughtfully. "Perhaps we should have a land demonstrationbefore I pay over the money."
"So you doubt my honesty?" the professor demanded.
"Not at all. It's only that I must be very careful before I purchase suchan expensive machine. I must satisfy myself that it will do everythingyou claim for it."
"You have just witnessed a successful demonstration. What more do youask?"
"A successful water test," Salt remarked softly, "does not necessarilymean a successful land test."
"I think we should have a land test," Mr. Johnson decided. "If youconvince me that the machine will work equally well under suchcircumstances, I will write the check instantly."
"A land test is impossible," the professor said stiffly.
"But why?" inquired Mr. Johnson.
"The dangers are too great. Windows would be smashed for many milesaround. Authorities would not permit such a test. Only with the greaterdifficulty did I obtain permission to discharge the mines under water."
"I had not thought of that," Mr. Johnson acknowledged. He hesitated, andit was evident that in another moment he would decide to purchase themachine without further tests.
"Mr. Johnson, I suppose you have witnessed tests made with your ownmines," Penny interposed. "Or have they all been made with those suppliedby the professor?"
The remark infuriated Mr. and Mrs. Bettenridge, as she had expected itwould.
"You and this young man are trying to discredit my machine!" he exclaimedwrathfully. "Please leave."
"Why, certainly," agreed Penny, but made no move to depart.
Seeds of suspicion already had been implanted in Mr. Johnson's mind.
"The young lady is right," he said. "I should request a test on a minewhich I provide myself."
"Ridiculous!" snapped the professor. "The machine will work equally wellon any mine."
"Then surely you should not object to one further test?"
"The delay is unnecessary."
"I am certain I can provide a mine within two days," insisted Mr.Johnson. "Suppose we set the next test for Thursday night at this samehour?"
Thus trapped, Professor Bettenridge could not refuse without losing thesale. Scowling, he gave in.
"Very well. But this will be the final demonstration. If you are notsatisfied Thursday night, the deal is off."
"Agreed," said Mr. Johnson.
Bowing to the Bettenridges, he departed. Others who had witnessed thedemonstration began to melt away. Only Salt and Penny remained.
Professor Bettenridge closed the door so that the conversation would notbe overheard. Then he turned angrily to the pair.
"Now what's your little game?" he demanded. "You deliberately tried toqueer my sale? Why?"
"Mr. Johnson seems like such an innocent little rabbit, maybe we thoughthe ought to be protected," Salt drawled.
"Protected! Why, he's being given the opportunity of a lifetime! How muchis it worth to you to keep out of my affairs?"
"Not a cent," Salt retorted. "We don't want any part of your deal. Butthere's something I did come here for--my camera."
"I've already told the young lady I know nothing about it. If you werestupid enough to throw it into a passing automobile, then you deserve tolose it. Now get out!"
Salt was tempted to argue the matter, but Penny took his arm, pulling himtoward the door. The professor slammed it hard behind them as they wentout into the night.
"That fellow is a crook!" Salt exploded. "I'll bet a cookie he has mycamera too!"
"Well, we can't prove it," Penny sighed. "After all, we did act in ahigh-handed way. We may have queered his sale to Mr. Johnson."
"A good thing if we have."
"But we have no proof the machine is a fake. With our own eyes we saw themine explode. Of course, we think Webb tampered with it in some fashion,but we're not certain of that either."
"The proof of the pudding will come Thursday night when and if the oldboy explodes Mr. Johnson's mine."
"He's just clever enough to do it, too," Penny said gloomily.
The couple had walked only a short distance up the lane when they werestartled to hear a shrill whistle in the darkness. It came from thebeach.
Halting, they waited. In a moment the sound was repeated. Then to theirsurprise, came an answering whistle from inside Professor Bettenridge'scabin.
"That must be Webb," Salt whispered, observing a shadowy formapproaching. "The whistle evidently is a signal to make certain the coastis clear."
As they watched, the hunched figure emerged from the darkness, wassilhouetted momentarily in the light which came from the cabin, thendisappeared inside.
"I wish we knew what they were talking about in there," Penny said. "Itmight clear up some of the mystery."
"Why not see what we can learn?" proposed Salt. "It's safe enough."
Taking care to walk softly, the pair stole back to the cabin. Crouchingby the window, they could hear a low murmur of voices inside. At first itwas difficult to catch the trend of the conversation, but graduallyProfessor Bettenridge's voice grew louder.
"I don't like it any better than you do," Salt and Penny heard him say,"but that's the way it is. If we're to finish the deal, we've got toexplode one of Johnson's mines Thursday night. The question is, can we doit?"
"Depends on the type of mine," Webb replied gruffly. "How soon can we
have it ahead of the test?"
"I'll insist that he deliver it here at least by afternoon. Will thatgive you time enough?"
"Sure, it won't take more than a half hour to fix 'er for the test,providing it can be done. But I ain't makin' no promises until I see themine."
"It's a chance we have to take," Professor Bettenridge said. "The dealwould have gone through tonight if it hadn't been for a couple of youngnewspaper fools who came nosing around here. They may make us troubleThursday night too."
"I ain't aimin' to get mixed with the police," Webb said uneasily. "Ifthis deal don't go through Thursday night, I'm quitting. We're in amighty risky business."
"But we stand to make at least $200,000," the professor reminded him."You'll get a third cut. If Johnson holds off Thursday night, I'll dropto $100,000. The thing we've got to do is to pull off that test okay andclear out."
Penny and Salt had heard enough to be certain that the men with whom theywere dealing were crooks of the first rank. Slipping noiselessly away,they trudged to the car.
"Now what do we do?" Penny questioned. "Notify the police?"
"We could," Salt debated, "but so far, it's only our word againstProfessor Bettenridge's. He'd probably convince the police he was only acrack-pot inventor who thought he had a wonderful machine. They might lethim go."
"Any other ideas?"
"A slick trick would be to fix that mine so it won't explode. Thatautomatically would cause complications and probably delay the deal withMr. Johnson."
"Just how do you propose to fix Mr. Johnson's mine?" Penny inquired. "Itwould take some doing."
"The mines are all kept in that shack on the beach?"
"Yes, Louise and I saw Webb working on one of them there. Evidently itwas the one the professor exploded tonight."
"He must have doctored it in some special way. Probably an untamperedmine won't explode."
"He'll fix Mr. Johnson's mine the same way, and then the test will appearsuccessful."
Salt nodded gloomily. He was lost in thought for several minutes, andthen he grinned.
"Maybe I have an idea!"
"What is it, Salt?"
The photographer switched on the car ignition. "Wait until Thursdaynight," he replied. "Can you get away from the office early?"
"Well, I really shouldn't--"
"I'll take care of that part," Salt said briskly. "Just sit tight, Penny.You and I will have some fun out of this affair yet, and maybe we'll saveMr. Johnson a tidy sum of money."