"Hadn't you better identify your property first?" said Jonah. "I mean, I don't want to interfere, but if it's a question of our arrest——"

The inspector hesitated, and the Chief Constable's face took on a darker shade of red. He was a coarse-looking man, generously designed and expensively over-dressed. For a moment I thought he was going to strike Jonah. Then he caught a heavy underlip in his teeth, turned on his heel, and strode to the Rolls-Royce.

He cast a proprietor's eye over her points. Then he stepped behind her as though to come to her other side. The next second he was back and shaking his fist in Jonah's face.

"So you've had the infernal audacity to alter the number-plates, have you?" he yelled. "Thought to bluff me, I suppose. You impudent——"

"One moment," said Jonah steadily. "Without looking at the dash, tell me your chassis number. Your chauffeur should know it."

"One double seven eight," came parrot-wise from the lips of the gentleman referred to.

"Thank you," said Jonah.

Grey Hat almost ran to the Rolls, tore open the bonnet, and stared at the dash—stared....

We waited in a silence so charged with expectancy as to be almost unbearable.

At last the Chief Constable straightened his back. His eyes were bulging and his face redder than ever. Twice he essayed to speak without success. Then—