"To go on, as soon as we found the bar and the spring mechanism we knew we'd been sabotaged. But that wasn't all. Etched on the bar was a rather good picture of a knight in armor, in the process of driving his sword through a rocket. Underneath was the inscription: Homo Terrestrialis."
Etched on the bar was a puzzling inscription
"I don't get it," Rick complained.
Gordon grinned. "Neither did we. And we still don't get it. But you can be sure we started a few balls rolling. First, Security checked every man's file again. They missed no one. Even the security officers and guards were rechecked. Then they started a program to find out who on the base had any talent as an artist. Nothing was found. The security chief sent photos of the etched picture and the whole bar mechanism to every security agency in the government, including the FBI, Central Intelligence, and the military. He drew a blank. No one had ever heard of anyone calling himself the Earthman, and the technique wasn't familiar."
The scientist paused long enough to eat a little more, then resumed.
"Meanwhile, we were getting a Viking rocket ready to launch. We checked it from nose to fins. We didn't miss a thing. Then we posted a guard around it, and a guard to watch the guard. We took no chances at all. The project engineer even slept near the rocket where he could keep an eye on it."