"Ah!" cried Ione, springing up. "Tense! Tensors! I have it!"
Phil gazed at her in alarm. She laughed; at first it was a strained laugh, but gradually it melted into her sunny one.
"No, I'm not crazy. I knew there was a way out, and I've been trying to reason it out. How simple. You remember the little jolts when you pulled at the vines and when you kicked the funny animal? Tensors. Matter and space are so closely interrelated that you can't move matter in or out of space without causing disturbance, recoils, and tremors in space. Those bits of matter were small, and produced only a slight disturbance. It takes about a hundred pounds of lead to swing this segment—"
"Oho! Got you!" exclaimed Phil. "Not so dumb! The safe!"
"Yes. The safe!" Ione cried.
"Throw it off and watch us swing, eh? What would happen?"
"I might calculate it if I knew the weight of the safe."
"No calculating when I'm around," Phil said. "It couldn't make things any worse. Try it first and calculate afterwards."
They got behind the safe and pushed, and their combined strength against it was about as effective as it would have been in moving the Peoples' Gas Building. They sat down again in despair.