Then we entered the dining-room together, partook of some wine which her ladyship offered us, and left the house in company--not, however, before I had promised to call again on the morrow and visit my patient. "Now, Hoefer, what is your candid opinion?" I asked my companion as we stood on the kerb, opposite the Marble Arch, awaiting the belated omnibus to take him back to Bloomsbury. "I don't like it, my dear frient," he answered dubiously; "I don't like it." And, shaking my hand, he entered the last Holborn 'bus without further word. On foot I returned to Bayswater utterly confounded by the curious events of the evening. By Hoefer's serious expression and preoccupied manner, I saw that the influence within or without that room of mystery was to him utterly bewildering. He had spent his life in the study of micro-organisms, and knew more of staphylococci, streptococci, and pneumococci than any other living man, while as a toxicologist he was acknowledged, even by his clever compatriots in Germany, as the greatest of them all. He had searched out many of the secrets of Nature, and I had myself at times witnessed certain, of his experiments, which were little short of marvellous. It was, therefore, gratifying that I had enlisted his aid in solving this most difficult problem. Yet, as I lay awake that night, reflecting deeply upon the curious situation, I could not arrest my thoughts from turning back to the tragedy at Whitton and the omission of those two names from the list of visitors furnished to the police. That her ladyship was a bosom friend of Mrs Chetwode's was quite plain, and that she was present, together with Beryl, earlier in the day, I had myself seen. Somehow, I could not get rid of the conviction that Sir Henry's wife, the woman who had taken this secret journey from Atworth to London to have a clandestine interview with some person whom she declined to name, knew the truth regarding the Colonel's death. I was plunged into a veritable sea of perplexity. If I could but discover the identity of La Gioia! That name rang in my ears, sleeping or waking. La Gioia! La Gioia! Ever La Gioia! Beryl held her in abject dread. Of that I knew from those words of here I had overheard at Whitton. She had declared that she would commit suicide rather than face her vengeance. What had rendered my adored one so desperate? As I sat over my lonely breakfast on the following morning, there being already a couple of patients in the waiting-room--clerks who had come for "doctors' certificates" to enable them to enjoy a day's repose--the servant brought in the letters, among them being one for me which had been forwarded from Shrewsbury by my mother.