A few days after this Bert, Harry and Frank were on their way to the village store to get some groceries for Aunt Sarah. As they came near the place, in front of which was a large porch, a man was seen peering around the corner of the building. At the sight of him Frank started and pulled Bert by the sleeve.
"What's the matter?" asked Harry's cousin.
"That man!" whispered Frank. "See him! That's the one who gave me the bad money—the Confederate twenty dollar bill. What can he be doing here? Oh, if I could only get Mr. Mason's money back from that man!"
"Let's wait and see what he is doing," suggested Harry. The man had not yet seen them. The boys could watch him as he seemed to be hiding back of the corner of the country store.
"He's up to some trick, I'm sure," said Bert.
A few seconds later Mr. Mack, the owner of the store, came out and walked down the village street. Hardly had he started off than the strange man quickly went into the store.
"He's going to take the money!" exclaimed Bert. "There's no one in the store now. He waited for Mr. Mack to come out, so he could go in and get the money."
"No, I don't think that," spoke Harry. "George Smith, a boy I know, works for Mr. Mack, and attends to the store when Mr. Mack goes out. George must be in there now."
"Well, that man is up to some trick, I'm sure!" exclaimed Frank. "How can we find out what it is?"
"We can go in the store through the back door," said Harry. "Come on, we'll do it, and sneak in quietly! Then we can see what's going on."