Chapter 11

Mason was grinning gleefully as he entered his office. Della Street said, “Why the cat-swallowed-the-canary expression, Chief?”

Mason said, “I was thinking of the logic and beauty of an old bit of philosophy.”

“Tell me the philosophy first,” she said, “and then I’ll tell you whether I agree with you.”

“The philosophy,” Mason said, “is a quotation having to do with an engineer.”

She knitted her brow. “An engineer?” she asked.

Mason, scaling his hat at the hat rack, said, “Uh-huh, and it goes like this: ‘For ‘tis sport to see the engineer, hoist by his own petard.’ ”

“Something seems to me,” she said, “that it’s going to get us into trouble.”

“On the contrary,” Mason told her, “it’s going to get us out of trouble. And, by the way, Della, do you know that one of the greatest troubles with police officers is that they lack imagination?”

“Just what in particular are you referring to?” she asked.