Steve excused himself. A few moments later he returned. "Hartson, I just took the liberty of ordering a scrambler placed on your phone switchboard, in case we need to hold any classified conversations between here and my offices. The phone man will install it today, if you have no objection." "Of course not," Hartson Brant said. "I think it's a sensible precaution, especially with one member of the team remaining in Washington." "What's a scrambler?" Barby asked. "A special device that turns phone conversations into jumbled gibberish so no one can understand them. You talk normally, and sound normal to the person listening. But anyone tapping in on the line gets only sounds that mean nothing." The agent's face turned grim. "Speaking of gibberish reminds me of the reason for the call. The _Washington Post_ carried a story in one of its columns this morning hinting that two scientists working on a supersecret project had been driven insane. It also hinted that the insanity was an effect of the gadget they were working on!" CHAPTER IV A Haircut and a Wink Rick held the Sky Wagon at the altitude to which he had been assigned by the control tower at Anacostia Naval Air Station in Washington. He was a little nervous because there was more air traffic around him than he had ever seen before. Across the Potomac River, so close that the traffic patterns almost interlocked, was busy Washington National Airport. Below him along the Anacostia River were two military airports; Anacostia, at which he would land, and Bolling Air Force Base. And to complicate matters slightly, Andrews Air Force Base was only a short distance away. A thousand feet above his head a tremendous Air Force Stratocruiser circled patiently. A thousand feet below him a flight of Navy Banshee fighters awaited clearance for landing. And climbing through the pattern came a division of Air Force F-80's. Rick's neck ached from swiveling around. Scotty was helping him watch for other aircraft. But in the rear seat, Hartson Brant and Julius Weiss talked a steady stream, as they had ever since taking off from Spindrift. Rick wished he were as oblivious to the traffic. Actually, he didn't know what they were talking about. Good as his scientific training was, they were in a realm where his young mind hadn't even probed. His earphones gave out: "Tower to Spindrift Flight. You are cleared to land. Approach from Northeast." Rick glanced down in time to see the Navy fighters peel off in a precision maneuver that was lovely to watch. Then, on their heels, he stood the Sky Wagon up on a wing and slid down toward the muddy river below. A short time later Rick called for instructions and was told to beach at Ramp Three. He located it without difficulty. Scotty climbed out on the pontoon and caught the rope thrown by a seaman. In a few moments they were beached.