The Disappearing Floor by Franklin W. Dixon

shaken, the boys climbed out to survey the damage.
    â€œLeft front tire’s flat,” Frank announced.
    â€œAnd there’s what did it.” Joe pointed to a wicked-looking array of tacks, bent nails, and broken glass scattered across the lane. “Those crooks must’ve tossed the stuff out of their car before we turned into the lane.”
    Disgusted, the Hardys got a jack out of their trunk and set about changing the flat tire.
    Suddenly a small object flew spinning from the trees across the lane. It landed near the convertible and sent up a gush of purple smoke!
    Frank stiffened in anger. “Look out, Joe!” he warned. “We’re being attacked!”
    Three men wearing gas masks had burst out of the woods and were charging toward the boys!

CHAPTER XIV
    Tigers’ Lair
    As THE smoke bomb burst and Frank yelled his warning, Joe was getting the spare out of the trunk, his back turned to the lane.
    Joe whirled at Frank’s cry and saw the gas-masked men only a few yards away. He struggled to hoist out the spare wheel and hurl it at them, but two of the thugs pounced on him.
    Frank rushed to his brother’s assistance, clutching the lug wrench. The third man grabbed his arm, twisted the wrench away from him, and knocked Frank sprawling in the ditch.
    In moments, purple smoke blanketed the area. The Hardys gasped and their eyes watered.
    Joe’s assailants overpowered and searched him, one yanking the lapel camera from his pocket.
    Frank was vainly trying to scramble to his feet, but every attempt met with a kick or blow that sent him toppling again. Then, as suddenly as they had appeared, the gas-masked thugs darted away through the smoke.
    Joe picked himself up, clawed out a handkerchief to hold over his eyes and nose, and groped his way toward his brother. Frank met him, and hand in hand they ran from the smoke area. In the distance they heard a car start and drive off.
    Frank and Joe finally reached clear air. Coughing, the boys slumped against a tree and looked at each other through swollen, red-rimmed eyes.
    â€œWow! We fell into a trap that time, Frank!”
    â€œSure did. Joe, we ought to get back to the car and radio the police.”
    â€œOkay, but let’s wait till the smoke clears.”
    Presently they were able to return to the convertible. Frank warmed up the short-wave radio and gave the police a description of the sedan.
    Joe, meanwhile, was mounting the spare. “Sorry I got us into this, Frank,” he apologized. “I shouldn’t have said anything to Hirff about Tigers’ Bight.”
    â€œNever mind. They still wouldn’t have nailed us if we’d used our heads.”
    â€œHow do you figure?”
    â€œThat guy rifling our glove compartment was probably a decoy,” Frank reasoned. “If he didn’t find what he was after, I’ll bet his orders were to let us spot him. They knew we’d go after him, so they had the tire-puncture trick and the gas attack all set up beforehand.”
    Joe shook his head ruefully. “Boy! Now I really feel like a chump!”
    â€œDid they get your camera?”
    â€œYes. I’m glad it was insured!” Joe grinned. “But there’s one thing they didn’t get.”
    â€œWhat’s that?”
    â€œTake a look in the glove compartment.”
    Frank did so, then turned in astonishment. “The film ! How did that get in here?”
    â€œSimple. I unloaded the camera while you were wheeling after ’em.” Joe chuckled as he wrestled the spare into the trunk. “I had a hunch there might be trouble if we caught up with those characters——and the glove compartment looked safe because it had already been searched.”
    â€œNice going, Joe!”
    As they were driving home, Joe remarked, “Hirff called the signals on that attack.”
    â€œSure, but try and prove it. He probably phoned his pals the second we left the airport and has