Cheyne slipped the purse into his pocket, and next moment he was walking along Dalton Road towards the station, free, well, and with the tracing in his pocket. Until that moment, in the inner recesses of his consciousness doubt of the bona fides of the trio had lingered. Until then the fear that he was to be the victim of some plausible trick had dwelt in his heart. But now at last he was convinced. Had the men desired to harm him they had had a perfect opportunity. He had been for the last hour entirely in their power. No one knew where he had gone, and they could with the greatest ease have murdered him, and either hidden his body about the house or garden or removed it in the car during the night. Yes, this time he believed their story. It was eminently reasonable, and as a matter of fact, it had been pretty well proved by their actions, as well as by the facts that he had learned at the Admiralty and elsewhere. They were at a standstill because they couldn’t read the cipher, and they really did want, as they said, the help of his and Joan’s fresh brains. From their point of view they had done a wise thing in thus approaching him—indeed, a masterly thing. Cheyne was not conceited and he did not consider his own mental powers phenomenal, but he knew he was good at puzzles, and at the very least, he and Joan were of average intelligence. Moreover, they were the only other persons who knew of the cipher, and it was the soundest strategy to turn their antagonism into cooperation.

He reached North Wembley to find a train about to start for Town, and some half hour later he was walking up the platform at Euston. He looked at his watch. It was barely eleven. An hour would elapse before Joan would reach her rooms, and that meant that he had more than half an hour to while away before going to meet her. It occurred to him that in his excitement he had forgotten to breakfast, and though he was not hungry, he thought another cup of coffee would not be unacceptable. Moreover, he could at the same time have a look over the cipher. He therefore went to the refreshment room, gave his order, and sat down at a table in a secluded corner. Then drawing the mysterious sheet from his pocket, he began to examine it.

As he leaned forward over his coffee he felt Joan’s purse in his pocket, and suddenly fearful lest in his eagerness to tell her his experiences he should forget to give it to her, he took it out and laid it on the table, intending to carry it in his hand until he met her. Then he returned to his study of the tracing.

There are those who tell us that in this world there are no trifles: that every event, however unimportant it may appear, is preordained and weighty as every other. On this bright spring morning in the first class refreshment room at Euston, Cheyne was to meet with a demonstration of the truth of this assertion which left him marveling and humbly thankful. For there took place what seemed to be a trifling thing, and yet that trifle proved to be the most important event that had ever taken place, or was to take place, in his life.

When he took his first sip of coffee he found that he had forgotten to put sugar in it, and when he looked at the sugar bowl he saw that by the merest chance it was empty. An empty sugar bowl. A trifle that, if ever there was one! And yet nothing of more supreme moment had ever happened to Cheyne than the finding of that empty bowl on his table at that moment.

The sugar bowl, then, being empty, he picked it up with his free hand and carried it across to the counter to ask the barmaid to fill it. Scarcely had he done so when there came from behind him an appalling explosion. There was a reverberating crash mingled with the tinkle of falling glass, while a sharp blast of air swept past him, laden with the pungent smell of some burned chemical. He wheeled round, the shrill screams of the barmaids in his ears, to see the corner of the room where he had been sitting, in complete wreckage. Through a fog of smoke and dust he saw that his table and chair were nonexistent, neighboring tables and chairs were overturned, the window was gone, hat-racks, pictures, wall advertisements were heaped in broken and torn confusion, while over all was spread a coat of plaster which had been torn from the wall. On the floor lay a man who had been seated at an adjoining table, the only other occupant of that part of the room.

For a moment no one moved, and then there came a rush of feet from without, and a number of persons burst into the room. Porters, ticket collectors, a guard, and several members of the public came crowding in, staring with round eyes and open mouths at the debris. Eager hands helped to raise the prostrate man, who appeared to be more or less seriously injured, while hurried questions were bandied from lip to lip.

It did not need the barmaid’s half hysterical cry: “Why, it was your purse; I saw it go,” to make clear to Cheyne what had happened, and as he grasped the situation his heart melted within him and a great fear took possession of his mind. Once again these dastardly scoundrels had hoaxed him! Their oaths, their protestations of friendship, their talk of an alliance—all were a sham! They were out to murder him. The purse they had evidently stolen from Joan, filling it with explosives, with some time agent—probably chemical—to make it go off at the proper moment. They had given it to him under conditions which made it a practical certainty that at that moment it would be in his pocket, when he would be blown to pieces without leaving any clue as to the agency which had wrought his destruction. He suddenly felt sick as he thought of the whole hideous business.

But it was not contemplation of the fate he had so narrowly escaped that sent his heart leaping into his throat in deadly panic. If these unspeakable ruffians had tried to murder him with their hellish explosives, what about Joan Merrill? All the talk about driving her back to her rooms must have been mere eyewash. She must be in deadly peril—if it was not too late: if she was not already—Merciful Heaven, he could not frame the thought!—if she was not already dead! He burst into a cold sweat, as the idea burned itself into his consciousness. And then suddenly he knew the reason. He loved her! He loved this girl who had saved his life and who had already proved herself such a splendid comrade and helpmeet. His own life, the wretched secret, the miserable pursuit of wealth, victory over the gang—what were these worth? They were forgotten—they were nothing—they were less than nothing! It was Joan and Joan’s safety that filled his mind. “Oh, God,” he murmured in an agony, “save her, save her! No matter about anything else, only save her!”

He stood, leaning against the counter, overcome with these thoughts. Then the need for immediate action brought him to his senses. Perhaps it was not too late. Perhaps something might yet be done. Scotland Yard! That was his only hope. Instantly he must go to Scotland Yard and implore the help of the authorities.