"Then you think there's a meaning behind all these equations, too?"
He nodded. "It's a message, not just a contact. They're going to an awful lot of trouble to beam out this message, and they're repeating it every seven hours. They haven't added anything new in the weeks we've been watching."
"I wonder how many years or centuries they've been sending out this message, waiting for someone to pick it up, looking for someone to answer them."
"Maybe we should call Washington...."
"No!"
Rizzo grinned. "Afraid of breaking radio silence?"
"Hell no. I just want to wait until we're relieved, so we can make this announcement in person. I'm not going to let some old wheezer in Washington get credit for this.... Besides, I want to know just what they're trying to tell us."
It was agonizing, painstaking work. Most of the formulas meant nothing to either one of us. We had to ransack the dome's meager library of microspools to piece them together. They started simply enough—basic chemical combinations: carbon and two oxygens yield CO2; two hydrogens and oxygen give water. A primer ... not of words, but of equations.
The equations became steadily longer and more complex. Then, abruptly, they simplified, only to begin a new deepening, simplify again, and finally become very complicated just at the end. The last few lines were obviously repetitious.
Gradually, their meaning became clear to us.