"Mr. Joyce goes to your club also?"

"Yes sir. I told you so when you called to see me first. I knew the name at once. Kidd knows him too, but he doesn't know Kidd. That was why I sent Kidd to Paddington. He's a fool, sir."

"True enough," replied Herrick dryly, "but even a fool can become dangerous in the hands of an unscrupulous scoundrel like Santiago. Oh, I do not know anything against him," added Herrick seeing the ferret's eyes twinkle. "I am only going by the little I do know."

"Not enough to jail him I suppose, sir?"

"Not yet, but there might be soon," replied Jim, glancing sideways at his neat companion. He well knew that Belcher and Kidd liked to know secrets in order to extort blackmail. A dangerous pair; but Jim knew how to deal with them. They were rather afraid of Jim. He knew too much.

Herrick had become acquainted with the ferret through having saved the life of his small daughter, and as this child was the apple of the man's eye, he adored Jim and was in the habit of speaking to him more freely than he otherwise would have done. Therefore Jim got to know more about the Private Inquiry Firm than was altogether wise. However, he could keep his mouth shut, and, as at present, he sometimes found the pair useful. But the connection was not a pleasant one, even so, and Herrick was wont to comfort himself with the reflection that when dirty work has to be done, no man can be nice in the choice of his instruments.

Directed by the ferret, the cab stopped at the corner of a Pimlico street in a quiet neighbourhood. There he left the doctor in the cab, and went along to reconnoitre. In ten minutes he came back.

"The Mexican has gone out," said Belcher, "he has been away an hour. But Joyce is in the sitting-room. Kidd saw his face two or three times at the window. If you creep along the street under the house he won't be able to see you."

"Right you are," said Dr. Jim climbing down, and paying off the cab--lavishly because he did not want a disturbance, "you wait outside both of you and keep an eye on the policeman. When you hear a shot"--

"You needn't tell me twice Dr. Herrick," said Belcher, his professional pride wounded. "Off you go sir, I'll stop hereabouts and whistle if the Mexican comes along. He doesn't know my real business."