He paused for a moment. Then he thought better of it and came to a sudden stop.

“Well, in the matter that we both remember,” he added finally.

“I want a little information from you, that I believe it is in your power to give,” said Burrell, taking a note book from his pocket and from it producing the scrap of cigarette he had taken from the gutter of the house in Burford Street. He placed it on the desk before his companion.

“I want you to tell me if you can who are the makers of these cigarettes, and whether they can be obtained in England?”

The other took up his glasses and perched them on the end of his delicate nose, after which he held the charred fragment of the cigarette up to the light. This did not seem to satisfy him, so he took it to the window and examined it more closely. He turned it over, smelt it, extracted a shred of the tobacco, smelt that, and at last came back to the table.

“That cigarette was made by my good friend Kosman Constantinopolous, of Cairo, a most excellent firm, but as yet they have no representatives in England. Some day they will have.”

“Where is the nearest place at which these cigarettes can be obtained?” asked Burrell.

“In Paris—if you like I will give you the address,” the other replied, “or better still I will get some for you should you desire to have some. They are expensive but the tobacco is good.”

“I won’t trouble you to procure me any just now, thank you,” Burrell answered. “I only wanted to try and fix the maker’s name. It comes into some important business that I am just now at work upon. I suppose I can rely upon your information being correct? It will make a big difference to me.”

“My good friend, you may be quite sure of that,” the other answered with pride. “I am Israel Zevenboom, the expert, and after fifty years’ experience, should not be likely to make a mistake in such a simple matter as that.”