"Quick! See if you can get the license number!" Penny cried.
"I can't. The car is too far away."
"I got the last three numbers," Penny informed with satisfaction. "—684. I want to write it down before I forget."
Susan supplied pencil and paper from her purse. Penny jotted down the number.
"Why did you want it?" Susan asked curiously. "You don't think that man was trying to steal a wheel?"
"I certainly do. Otherwise why would he have left so hurriedly when we came up? See, the wheel is only half changed."
They walked over to the nearby automobile to look. The wheel obviously was a new one and apparently had not been damaged.
"That man was a tire thief all right," Penny announced. "It means that the Molberg gang is starting activities again. I must get in touch with Father immediately."
"I'll take you straight home," Susan offered.
"If I'd been just a little quicker I'd have caught the entire license number," Penny said regretfully. "Even so, it may be possible to trace the car."