"The last of the tragedies," he said.

"Jansen!" Russell exclaimed. "And stone dead beyond a doubt. But what is that strange bandage around his head?"

Jansen lay stiff and stark with his bloated face turned up to the light. Around his forehead was a white bandage so stiff and tight that it might have been made of solid metal. It was hard and hollow to the touch as Uzali's fingers drummed upon it.

"Here is the mystery of the five knots," he said. "Don't you see what has happened? Jansen attempted to make a dupe of my fellow-countrymen, but they were too cunning for him. They were not drugged when he left his lodgings; they were only shamming. They followed him here, must have travelled by the same train, and they tracked him to these vaults where I dare say they have been before. Directly he saw them he must have known his end was come; let him turn and twist as he liked, there was a finish to Jansen. Whilst one held him at bay the other lighted that scent you know of, and, as soon as the wretched man's senses failed, they bound that cloth about his forehead and the five deadly knots did their work. The thing is put on wet, but dries in a few moments with a tremendous pressure that gives the brain no chance whatever. It is practically impossible even for the cleverest surgeon to guess it is concussion of the brain, since there are no signs of violence. And yet, after the application of those terrible knots for an hour or so, no victim could recover. By pure good luck Mercer twice saved the life of Samuel Flower, for each time my fellow-countrymen were interrupted by him and managed to get away, leaving no trace of their secret. In Jansen's case it was different. We had cut off their avenue of escape and they had only themselves to think of. And they met their fate, too."

"But this is really worse than the other," Russell said with a shudder. "The whole story is bound to come out now. We cannot take this wretched man outside and throw him into a ditch."

"That is true," Uzali said grimly. "But we can remove all signs of the mischief. I know we are running a risk. I know we are placing ourselves within reach of the law, but I am going to take the chance all the same. Go to the dining-room and fetch me a decanter of water so that I can damp this bandage off. Besides, since no one knows Jansen or anything about him, it will be reasonable to assume that he was one of the burglars and that they had quarrelled with fatal results."

Russell was too upset by the events of the night to make any protest. He seemed to have hardly strength enough to attend to himself. In a dazed way he crept back from the dining-room with a decanter of water with which Uzali proceeded to remove the bandage until the remotest trace of the cause of death had disappeared.

"It is amazing," Russell murmured. "No wonder a doctor would be puzzled to give a certificate. He looks now as if he had died peacefully in his sleep."

"That is so," Uzali said coolly. "And now let us be convinced that he came here for some felonious purpose. I am certain I shall find housebreaker's tools in his possession. Ah, I told you so!"

From the breast-pocket of Jansen's coat Uzali produced a small but powerful jimmy along with a neat case of instruments which left no doubt of the purpose for which they were used. With the jimmy in his hand Uzali crossed the floor and made a deliberate attack on one of the big cases. Presently the lid came off with a resounding crash and a quantity of sacks were exposed to view. Under the sacking lay a number of wash-leather bags evidently of considerable weight, for Uzali had to exert all his strength to release two of them and lay them on the floor. He untied the knots which bound the sacks and plunged his hand inside. His fingers came out sparkling and shimmering in the candle-light.