Brodie came strolling along the asphalt walk, puffing out his cheeks and gazing about him, as though exercise and an interested contemplation of the river were the sole reason for his peregrinations. He appeared to recognise the two men only in the act of passing them. He at once stopped short and greeted them in his usual hearty fashion. "Pleasant little spot, this, for an hour's recreation," he declared. "I was thinking about you, by the by, Grimm, as I walked along." "I am flattered," was the calm reply. "I should have thought that all your attention would have been engrossed upon the little affair over yonder. I understand that Madame de Borria has placed the recovery of her necklace in your hands. Quite a feather in your cap, my friend, if you succeed." Brodie glanced casually at the block of buildings in front. "Yes," he assented, "I have that on my mind, of course. By the by, were you going back to your rooms, by any chance?" "I was on my way there." "Come, that's fortunate. With your permission, we will walk along together." The two men rose and they all strolled along towards the hotel. "Curiously enough," Brodie went on, "I was wondering whether I should be likely to run up against you to-day, Grimm. We wanted to ask your advice, Inspector Ditchwater and I, about that little affair the night before last. You heard the particulars, I suppose?" "I was in the smoking-room," Harvey Grimm admitted, "when Madame came running down in her dressing-gown. Naturally, we heard the story told a good many times." "Just so! Madame, it seems," the detective continued, "heard nothing, knew nothing, until late in the morning, when her maid told her that the floor valet was unable to obtain admittance to her husband's room. She at once stepped through the communicating door and found him still unconscious, with the necklace missing." "Has he recovered yet?" Harvey Grimm enquired. "Is he able to give any account of what happened?" "I saw him for a few minutes last night," Brodie replied. "He seemed still very dazed and confused, but he talked quite coherently. His story is simple enough and doesn't help us much. He was fast asleep--he can't even say at what hour--when he was awakened by the thrusting of a gag into his mouth and a bandage over his eyes. He thought at first it was a nightmare and he tried to spring out of bed. He was held down, however, quite firmly, and something placed under his nose which made him feel just as though, to use his own words, he was sinking back to sleep again. He remembers nothing more until the morning, when he was found by his wife. The moment they released the gag he was violently sick, and the room certainly smells ethery." "What about the necklace?"