The Curve is Exponential
"I couldn't see the instruments," said Weil. "I had to watch Fermi every second, waiting for orders. He face was motionless. His eyes darted from one dial to another. His expression was so calm it was hard to read. But suddenly, his whole face broke into a broad smile."
Fermi closed his slide rule---
"The reaction is self-sustaining," he announced quietly, happily. "The curve is exponential."
The group tensely watched for twenty-eight minutes while the world's first nuclear chain reactor operated.
The upward movement of the pen was leaving a straight line. There was no change in indicate a leveling off. This was it.
"O.K., 'Zip' in," called Fermi to Zinn who controlled that rod. The time was 3:53 p.m. Abruptly, the counters slowed down, the pen slid down across the paper. It was all over.
Man had initiated a self-sustaining nuclear reaction - and then stopped it. He had released the energy of the atom's nucleus and controlled that energy.
Right after Fermi ordered the reaction stopped, the Hungarian-born theoretical physicist Eugene Wigner presented him with a bottle of Chianti wine. All through the experiment Wigner had kept this wine hidden behind his back.
Fermi uncorked the wine bottle and sent out for paper cups so all could drink. He poured a little wine in all the cups, and silently, solemnly, without toasts, the scientists raised the cups to their lips - the Canadian Zinn, the Hungarians Szilard and Wigner, the Italian Fermi, the Americans Compton, Anderson, Hilberry, and a score of others. They drank to success - and to the hope they were the first to succeed.
A small crew was left to straighten up, lock controls, and check all apparatus. As the group filed from the West Stands, one of the guards asked Zinn:
"What's going on, Doctor, something happen in there?"
The guard did not hear the message which Arthur Compton was giving James B. Conant at Harvard, by long-distance telephone. Their code was not prearranged.
"The Italian navigator has landed in the New World," said Compton. "How were the natives?" asked Conant. "Very friendly."
Back row, left to right, Norman Hilberry, Samuel Allison, Thomas Brill, Robert G. Nobles, Warren Nyer, and Marvin Wilkening. Middle row, Harold Agnew, William Sturm, Harold Lichtenberger, Leona W. Marshall, and Leo Szilard. Front row, Enrico Fermi, Walter H. Zinn, Albert Wattenberg, and Herbert L. Anderson.