On the night that Dick had found him examining the ruins of the Abbey, Mr. Gilder had returned to the cut road when he thought the coast was clear and had discovered yet another in quest of the treasure. He had witnessed the interview between the two men and had followed Arthur back to Willow House with no other intention than to offer his help, for a consideration, in discovering this mythical fortune. For Mr. Gilder had heard quite enough that day he surprised his employer with Mary Wenner, to know that somewhere under the Abbey lay either the fortune or its key. He had overtaken Arthur on the drive, and Arthur was in an unpleasant mood: hot with the man at the interruption of his search, smarting under the sting of Dick Alford’s sarcasm. At first, startled by the unexpected apparition of his head clerk, Arthur had snarled round on him, and there and then discharged him from his service and defied him to do his worst. It was Gilder who had struck the first blow. When Arthur was in his more unpleasant moods he said things that no self-respecting man could endure, and the black eye which the lawyer nursed was an advertisement of his indiscretion. Gilder might be a bookmaker, but he was not a thief. At least, “thief” was rather an extravagant description of his duplicity. He went back to London half crazy with rage, but a day in bed restored his mental equilibrium and he sat down to plan how best he could frustrate any plans which his late employer had formed for gaining possession of the treasure. By this time Gilder, too, was convinced; his last doubts removed. He had been sceptical as to the treasure’s existence, but he knew such things had happened, and he had a natural desire to be in any scheme which produced immediately and without great labour a vast, undreamed-of sum. His cut lip healed in a few hours, though it was still swollen, and toward the evening of the second day after his retirement from the firm of Gwyn & Gwyn, he dressed himself with great care, and, calling a taxi, drove to an address he had once scribbled on his white shirt-cuff. Mary Wenner occupied a tiny flat, every compartment of which might have been contained in one large-sized room. It was perched on the top floor of an apartment house near Baker Street--37, Cranston Mansions. She enjoyed an uninterrupted view of the Metropolitan Railway and such shunting operations as are carried out in that busy centre, and she was as a rule free from callers; for there were no elevators in the house, and to climb up four steep flights of stairs was something of an undertaking. Mr. Gilder was not strong for physical exertion and cursed the parsimonious builder who had neglected to put in this easy method of transportation. Nevertheless, he climbed, and presently was ringing at the polished bell of No. 135.