The address he was looking for was in Old Sugarhouse Close, a ramshackle building situated beside the candle works. The air was full of the smell of tallow, the meaty stench of rendered animal fat. There were other, rawer scents too, with the flesh, fowl and fish markets abutting the factory. The last was always on the breeze, fish being a pervasive aroma this close to the port, as much a constant as the cries of the gulls.

Raven found the door that he was looking for and was about to knock when he heard the sound of crying. He paused. It was not the tormented screams of a woman in labour but the lusty bawling of a healthy new-born.

He sighed. Leith was a long way to have come for this. It did happen, of course. Uti veniebam natus: born before arrival of the medical attendant. It was a common enough entry in the outdoor casebook. The professor liked to say that he too had escaped the intervention of the local doctor in this way. Then, as always, Simpson had been in a bustling hurry to get on.

Raven rapped upon the door. He heard the scuffling of hasty footsteps and then it opened, a grey-haired woman standing before him cradling a naked infant in her arms, its skin still smeared with blood and vernix.

Raven held up his battered leather bag to identify himself.

‘I’m here for Mrs Corrigan, though I don’t suppose I need to ask if this is the right place.’

‘You took your time,’ the woman said.

He wondered if she was a local midwife. They had a tendency to resent the intrusion of doctors upon what they considered to be their territory. The meddlesome accoucheur with his forceps.

He smiled in what he hoped was a placatory manner.

‘Dr Raven. At your service.’

The woman stood her ground for a moment before stepping aside to let him enter. A short passageway led to two closed doors.

‘Where is the mother?’ he asked.

She nodded towards one of the doors. ‘In there. Afterbirth has still to come away.’

‘How long since the birth?’

‘A while.’

‘Could you perhaps hazard a guess as to the precise time?’

‘Not long.’

‘Has there been any bleeding?’

She looked at him askance. ‘There’s always a bit of blood when a child is born.’

‘I mean brisk bleeding. Flooding.’

‘I’d hardly be standing here talking to you if that was the case.’

He noticed a nautical chart hanging on the wall.

‘The father is a sailor?’ he suggested.

The woman frowned, giving the tiniest of nods, perhaps conveying that this was hardly a complex deduction given they were in Leith.

‘He is at sea now.’

‘When does he return?’

She rolled her eyes. ‘More of an if than a when, if you ask me.’ She lowered her voice. ‘It is Miss Corrigan,’ she added archly.