The letter was followed by a note from the editor, who informed his readers that for legal reasons the correspondence on that issue was now closed.

Frances’ perusal of the papers for the last six months of 1877 revealed that nothing of any great significance had occurred. There were no violent street robberies, no stabbings, just the usual minor thefts, assaults and damage to property carried out while under the influence of drink, two small fires and an omnibus accident. None of these incidents had happened on the day or even the week that Edwin Antrobus returned to London, assuming that he had done so. There were a series of articles about Antrobus’ disappearance and appeals for anyone with knowledge of what had happened to him to write to the newspaper, followed by letters from humorists, frauds and people with fantastical imaginations as well as some honest speculation, none of which were remotely helpful.

Leaving the Chronicle offices, Frances walked along the busy thoroughfare of Ledbury Road and along Chepstow Crescent, passing the school where Dr Goodwin had once been a consultant and with which he was now in dispute. A tall white-fronted house, it was bounded by a low wall and ornamental gates, the path leading to the front steps flanked by stone urns filled with tumbling masses of colourful flowers. Frances smiled at such a thoughtful touch for children who could not hear, providing pleasure to their other senses. A signboard, still glistening as if freshly painted, announced that the school was now called The Bayswater School for the Deaf and employed the most modern and approved German methods of instruction under the guidance of headmaster J. Eckley, special consultant to the Society for Training Teachers of the Deaf.

The side of the school was close by a narrow lane leading to the cottages of Pembridge Mews, but a turn of the corner brought Frances to the more important properties of Pembridge Villas.

Dr Goodwin’s door was opened by a maid in her twenties, neat and smart, with an intelligent look. Frances presented her card, and the maid, who knew of the appointment, at once invited her in. A tall sturdy youth was standing in the rear of the hallway and not by chance: he was obviously curious about the visitor and looked at Frances very carefully. He ventured forward shyly and made a respectful little bow. He was a good-looking boy, with light brown eyes and bronze curls, on a fair way to becoming a handsome man.

‘Good morning,’ Frances greeted him. He smiled, but made no reply.

The maid turned to the youth and instead of speaking took a little notebook and a pencil from the pocket of her apron, wrote a few words, then showed him the page. He smiled even more broadly and nodded.

‘This is Mr Isaac Goodwin, Dr Goodwin’s son,’ the maid explained. ‘He is deaf, so we speak by writing our conversation. He can also speak with signs, and I intend to learn them so as to be more useful.’

Isaac wrote in the maid’s notebook.

‘He writes that he is very interested to meet you as he has read about you in the newspapers. If you go with him he will show you to his father’s study.’

Isaac bowed again, and indicated that Frances should follow him, which she did, feeling strangely tongue-tied. They reached a door and he knocked very deliberately three times. It was clearly a signal, one that he could not hear, but a means of telling the occupant of the room that it was he who was about to enter, no reply being appropriate.

After waiting a few moments, Isaac opened the door and they entered a comfortably furnished study. The gentleman who rose to meet them was about sixty, showing the rounded figure that often came unbidden with age, a pleasing though not handsome face, short whiskers and a ruff of grey hair around a bald pate. Frances, who was more than the usual height for a woman, found herself looking down on him as they shook hands. He did not, she thought, look like a man with what Lionel Antrobus had called ‘a reputation’ but, she reminded herself, cruel seducers and reprobates could be of any age and appearance. There was a conversation between Isaac and his father, carried out entirely in rapid gestures, before the youth, making another respectful obeisance to Frances, departed.

‘You are unfamiliar with the sign language of the deaf, I take it,’ observed Goodwin, ushering Frances to a chair and sitting at his ease. The wall behind the desk was lined with bookshelves closely filled with volumes, some of them, judging by the worn leather of their spines, of considerable age.

‘I am, yes. Is this something you have devised?’

‘Oh no,’ he assured her, ‘finger spelling and signs have been used since antiquity as the secret language of spies, and they have been employed for the education of the deaf for hundreds of years. The very youngest children quickly learn to converse and soon become proficient. By the use of signs a teacher can impart the skill of reading, and a complete education may be had.’

‘Your maid told me she intends learning the signs, I find that very commendable.’

‘Yes, she is a capable girl, who might yet become a valuable assistant.’

Frances approved his unusual insight. It was the habit of too many ladies and gentlemen to either ignore or underestimate their servants and assume a level of understanding less than their own, a capital error in her opinion. An individual from a family of substance might receive the best education money could buy and still be a fool, whereas his servant, who had not been so fortunate, could easily outstrip him in wisdom.

‘I see that you are admiring my library of medical works,’ smiled Dr Goodwin. ‘I have heard that you have some knowledge of medicine yourself.’

‘My late father was a pharmacist and taught me many of the skills of that profession. It was my intention at one time to study for the examinations, but it was not to be.’ Even as she spoke, Frances remained more than a little distracted by the expression ‘secret language of spies’, which had created some interesting thoughts. ‘Do you have any works on speaking with signs?’

‘I not only have them but I am the author of several, as well as volumes on the anatomy and diseases of the ear. It has been the one study of my life,’ he added, with some feeling. ‘My father was born deaf and my mother became deaf at the age of five after contracting scarlet fever. I owe it to their hard work, their struggle to provide me with schooling they could ill-afford, to do all I can for those similarly placed. Unfortunately the ear and its diseases is a subject largely neglected in the education of medical students. If as much effort was made to inform the medical profession as is expended in peddling the supposed cures of quacks and charlatans, we might have made better progress than we have.’

‘And you acted as medical advisor to Mrs Harriett Antrobus, whose husband has been missing for the last three years.’

Goodwin looked a little less easy in his manner and placed his fingers on the letter he had received from Frances, which lay unfolded on his desk. ‘I did. I am not sure if I can offer any information that can assist you in your enquiries but I will do my best.’

Frances took out her notebook and pencil. ‘Tell me about how you first met Mr and Mrs Antrobus and your impression of them.’

‘I expect you have already interviewed Mrs Antrobus.’

‘I have.’

He nodded. ‘And her brother-in-law, who in my opinion carries wilful ignorance to excessive extremes.’

‘Yes.’

He looked at her searchingly as if to try and judge what she thought of those two individuals. His general air of concerned amiability could not conceal a keen mind constantly in use. ‘Following some correspondence in the newspapers, I received a letter from Mrs Antrobus, who wrote to me at the Central London Throat, Nose and Ear Hospital appealing for my help. From the description of her symptoms I felt sure that she was suffering from a condition known as hyperacusis, that is she experiences severe pain from everyday sounds, with or without tinnitus aureum, which is noises in the head not of any external causation. That being the case, her medical practitioner had done her a terrible disservice in convincing her family that she was losing her mind. In my very specialist practice it is not, I am afraid, rare to uncover such errors that have been the cause of the unhappy patients being committed to asylums for the insane. I called upon the lady and carried out an examination in the presence of Mr Antrobus, which confirmed my original opinion. I could not offer a cure. There were some treatments it was worth employing and these were tried but they were not successful. My main advice was to tell her not to sit all day in complete silence, which she had been doing, but try to introduce some gentle pleasurable sounds, which might act as a balm to soothe her ears. At my suggestion Mrs Antrobus resumed her study of the piano, which she had previously abandoned, and this has given her some relief.’