 What action did Don consider for testing the water flow in Superior?
Radio messages stated simply that Superior had seceded from Earth. But Don Cort, stranded on that rising town, was beginning to suspect that nothing was simple about Superior except its citizens. He backed up two hundred feet, set out flares, then sped off to a telephone. The state police converged on the former site of Superior from several directions. Communicating by radiophone across the vast pit, they confirmed that the town undoubtedly was missing. A pilot who flew over it reported that it looked as if a great ice-cream scoop had bitten into the Ohio countryside. The train's schedule called for it to pass through but not stop at Superior at 11:58. A National Guard officer volunteered to take a jeep down into the pit, having found a spot that seemed navigable. He was gone a long time but when he came out the other side he reported that the pit was concave, relatively smooth, and did not smell of high explosives. The Governor of Ohio asked Washington whether any unidentified planes had been over the state. The Pentagon and the Atomic Energy Commission denied that they had been conducting secret experiments. A United Airlines pilot found Superior early on the morning of November 1. The object loomed out of a cloudbank at twelve thousand feet and Studley changed course to avoid it. A few minutes later he had relayed a message from Superior, formerly of Ohio, addressed to whom it might concern: It said that Superior had seceded from Earth. One other radio message came from Superior, now airborne, on that first day. Don Cort had been dozing in what passed for the club car on the Buckeye Cannonball when the train braked to a stop. If the girl had given Don Cort more than that one glance, or if it had been a trained, all-encompassing glance, she would have seen a man in his mid-twenties—about her age—lean, tall and straight-shouldered, with once-blond hair now verging on dark brown, a face neither handsome nor ugly, and a habit of drawing the inside of his left cheek between his teeth and nibbling at it thoughtfully. Don hesitated, shrugged at the redhead, said, "Excuse me," and followed the conductor. Don made his way up to the locomotive and found a bigger knot of people gathered in front of the cowcatcher. Don saw two men who must have been the engineer and the fireman talking to an old bearded gentleman wearing a civil defense helmet, a topcoat and riding boots.
 Taking a rowboat over the edge to see what would happen.
 Taking a rowboat over the edge to see what would happen.  Jumping into North Lake to see if there was an electrical current.  Swimming through the stream to see what would happen.  Throwing something into the stream and seeing if it would funnel back into Superior.