Grinning a little nervously, the engineer took the headset from Norcross and adjusted it to his own head. He stared into the now empty interior of the cube. “What do I do?” he said.

“Build a copy of your XB-91 and put it through its paces,” Nagle suggested.

Slowly there appeared a fuzzy, highly asymmetrical outline of the Ninety-one. Gunderson laughed uncertainly at his own creation. “Looks more like the ghost ship of the Ancient Mariner. What the devil’s the matter with the engines on the right wing? They won’t fire up.”

“Turn the plane around,” Norcross suggested.

Clumsily the model turned on its own axis, the tail disappearing in the process. Gunderson restored it. The engines on the left wing were out now, while the others were going.

“Can’t keep it lit up on both sides,” he complained. He felt moisture starting out on his forehead in the strain of maintaining the image.

“That’s a lot better than most of us do the first crack,” said Norcross. “We engineers pride ourselves on our visual ability. This shows us where we really stand.”

Gunderson shook his head unhappily and took the headpiece off. He extended it to Montgomery. “Try your luck, Gene. See if you can build a Ninety-one, complete with wings and tail.”

Montgomery felt as if something had frozen inside him. He couldn’t have taken the headpiece if his life depended on it, he thought later. “No,” he said thinly. “I’m going to expose my ignorance in private, first.”