“I’m sorry, I’m sure, sir,” he said at last. “I wasn’t told who you were, see? In fact, there’s a lot I wasn’t told.” He hesitated, and then the grievance which had almost demoralized him came out abruptly. “The Saltbridge police—I heard you say Saltbridge, didn’t I?—were very sharp on the cause of old Mayo’s death, weren’t they?”
“Very. The inspector up there was once an instructor in unarmed combat. It was just very good luck.”
“Perhaps so. But that blow is undetectable, let me tell you. It can’t be traced. It’s the one it’s too dangerous to tell the public about.” He was actually arguing and, as Campion began to recognize the type, became more and more his smart-aleck self. “It fractures the hyoid bone,” he persisted. “There’s nothing to see on the skin, and it’s never suspected.”
“H
