Part 31 (1/2)
”An automobile stopped by the roadside. I'm sure of it. Maybe it's my father!”
”He couldn't have reached here so soon.”
”You don't know Dad,” Penny chuckled. ”He drives like the wind. It certainly sounded like the engine of our car.”
”Let's have a look before we cut the boat loose,” Salt said, slipping a knife back into his pocket.
”I'll go,” Penny offered. ”You wait here.”
Before Salt could stop her, she darted away into the darkness. Crawling under a barbed wire fence, she took a short cut to the road. Even before she saw the car, she heard a voice which she recognized as her father's.
”Dad!” she called softly.
He was with another man whom Penny hoped was Major Bryan. As the two came toward the fence, she saw that it was indeed the Army officer.
”Dad, how did you get here so quickly?” she greeted him. ”Salt and I didn't expect you for at least another twenty minutes.”
”I was lucky enough to get hold of Major Bryan right away,” Mr. Parker answered, climbing over the fence. ”Now I hope you haven't brought us on a wild chase, Penny. What's up?”
”Come with me and I'll show you,” she offered. ”That's easier than explaining everything.”
Major Bryan, a well-built man of early middle age, asked Penny several questions about Professor Bettenridge as the three walked hurriedly toward the lake.
”From your description, he seems to be the man I'm after,” he declared grimly. ”If he's the same person, his real name is Claude Arkwright and he's wanted for impersonating an officer and on various other charges. He pulled a big job in New York three months ago, then vanished.”
Salt was waiting at the lake. ”What's our move?” he asked, after relating everything that had occurred that night. ”Shall we cut the boat loose?”
”First, let me examine those mines,” the major requested. ”Can we get into the shack?”
”I can pick the lock, but it takes time,” Salt offered.
”We'll break it,” the major decided. ”Those men may return here at any minute, so there's no time to lose.”
The door was forced open and Penny was placed on guard to watch the hillside for Webb or anyone in the professor's party.
There was no light in the shack, but both Mr. Parker and the major had brought flashlights. Salt pointed out the mine which had been doctored by Webb. Carefully, the Army officer examined it.
”I can't tell much by looking at it for the work has been cleverly concealed,” he admitted. ”But from what you've told me, I am quite certain how the mine is made to explode.”
”How is it done?” Salt demanded.
”After the hole is made, a chemical--probably sodium--is inserted. Then another substance which melts slowly in water is used to seal up the opening.”
”Then that explains why Webb delayed so long in giving the signal after the mine had been dropped into the water!” Penny exclaimed from the doorway. ”He was waiting for the substance to melt!”
”Exactly,” agreed the major. ”If my theory is correct, only the action of water is required to explode this mine. The professor's machine, of course, has nothing whatsoever to do with it.”
”Why don't we explode the mine now?” Penny suddenly proposed. ”That would put an end to the professor's little scheme.”