In the case of Reid, it was the caduceus that marked him as a medical man. The middle hexagon of the three bore the symbol that further classified the man. Each letter, was in a small hexagon, two above, three below.

Both were specialists, drafted for work in a super-specialty, with military rank for convenience and, considering the applications of the field, somewhat out of necessity. He wore his uniform with the same indefinable unnaturalness that the other did. His sandy hair lay back smoothly but his short, graying mustache bristled. 'Nearly got me that time,' said Colonel Donald Reid, calmly. He tried to bend the paper-clip he was manhandling back into shape and it flicked out of his hand. Carter's eyes were pouchy and the corners of his mouth sagged. General Alan Carter looked up glumly when the colonel walked in. The passenger didn't look particularly striking or impressive, but at the moment, he was the most important man in the world. He glanced at the only other man in the large passenger cabin-napping for the moment, with his chin buried in his chest. The agent aboard knew that his part of the job wouldn't be finished till the plane touched down and that the last hour would be the longest.

It nosed through the cloud banks on a trip that took it twelve hours where five might have sufficed with a rocket-powered supersonic. It was an old plane, a four-engine plasma jet that had been retired from active service, and it came in along a route that was neither economical nor particularly safe.

And finally, Isaac Asimov, who lent his pen and great talent to give form and reality to this phantasmagoria of facts and fancy. Bixby and I wrote our original story, little did we know where it would lead or what would become of it in the hands of men of great imagination and superb artistrySaul David, the film's producer Richard Fleischer, the director and inspired conjurer of fancy Harry Kleiner, who wrote the screenplay Dale Hennesy, the art director and an artist in his own right and the doctors and scientists who gave us so much of their time and their thinking. For all of us, it was a long and arduous task and a great challenge, but also one of deep satisfaction and, I may say, of great delight. This story, which has grown into both a book and film, has several authors, all of whom have contributed to its present form in many different ways. 10 HEART 11 CAPILLARY 12 LUNG 13 PLEURA 14 LYMPHATIC 15 EAR 16 BRAIN 17 CLOT 18 EYE

Fantastic Voyage by Isaac Asimov