In contrast to Raven, Archie was the epitome of respectability. A good man from a good family. Yet this façade disguised a radical heart. His egalitarian views put the liberal sensibilities of Dr Simpson in the shade. Sarah found his company intoxicating and even from an early stage he seemed to encourage her interest. Dr Simpson had prescribed fresh air and exercise as part of the treatment for Archie’s ailment and he often invited Sarah to join him in his perambulations around Edinburgh.

She remembered the day they had climbed to the top of Calton Hill, the view along Princes Street, and of course of the Bridewell and Calton Jail. He took her to the tearoom at Nelson’s Monument and paid the fee so that they could climb to the top of the tower. Afterwards they sat outside on a stone bench and talked about their plans for the future. She had been cold, and he had put his arms around her. He had suggested to her that perhaps they could face the future together. He had kissed her then, which had sealed their collective fate.

She was aware even then that a barrier had been crossed. She was mindful that many would have viewed this as a seduction and that she had been foolish to go along with it. She knew of the dangers facing housemaids who had relations with those above stairs, clandestine trysts behind closed doors. But their relationship was no secret; it had been conducted in the open, and thus was potentially more damaging to Archie than to herself. As a result, she had been convinced that his intentions were good. There was no subterfuge or coercion. There was no deception. Theirs was a union of equals. There was no shame in what they had done.

Things moved rapidly from that point on. It was never acknowledged but seemed mutually understood: they did not have time to waste.

She vividly remembered her joy at leaving this house not so long ago, to be married and live with her husband in the home that they had made together on Albany Street. How happy she had been to find herself not yet twenty and mistress of her own house. Her happiness was only tempered by the knowledge that it would not last.

Archie soon followed his luggage and was helped up the stairs to his new quarters, Raven providing a shoulder for him to lean on. Sarah could not help but smile at the sight of it. She had not thought to see these two men become so close.

Archie stumbled at the top, but Raven grabbed him before he could fall, strong arms encircling Archie’s emaciated frame.

‘I thought I told you to lay off the brandy at breakfast,’ Raven said.