Back in the parking lot, he found the compass he had dropped and took it back into the store. It turned out the compass did not point to the door from inside the store. This was not a possibility he had considered, and it made the problem more complicated. He assumed that there was something magnetic in the door that drew the compass, even from the back of the building, but once inside, it continued to point into the store. He wandered around the aisles until he noticed the sphere start to wobble, then he walked in the direction it pointed. Near the refrigerators, he found a spot where the sphere spun inside its housing. He backed off, and the pointer stabilized. He performed further experiments. No matter where he stood, the arrow pointed to this spot. He returned to it and the ball resumed spinning. He let it do so for a full minute and felt the compass grow warm in his hand. One step back again, and it halted. He inspected the spot on the floor where the compass went haywire, but could find nothing remarkable about it. On his way back out the door, he collected two magnets he found stuck to one of the cash registers.

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