I rested my forehead against the cool glass of our carriage window. We’d spent the last two weeks in Dar es Salaam, and if we were still there I would have been stretched out along the jetty with Maud and Lucy – the daughter of my father’s friends – soaking up the warmth of the wood beneath us, and listening to the shouts of the men unloading fish and spices along the harbour. In front of us, moored dhows would be bumping gently against each other in the waves, and kingfishers dive-bombing the water in flashes of blue and orange. Across the bay was Zanzibar, home to the sultan. One afternoon I’d taken my father’s binoculars out to look at the island, a stretch of brilliant white sand dotted with palms and matched by the whitewashed palace and fort at its edge. To the left I could see an Indian banyan tree, alive with vervet monkeys, and behind that, the shaded labyrinthine streets of Stone Town. Children darted in and out of focus, rusted-red iron roofs sloped upwards, and bedsheets, used in the place of curtains, flailed outwards in the breeze. ‘That’s the breath of God,’ Maud said, when I showed her. I didn’t see how Kenya could be better than that.

Along the train, doors began to slam.

‘Theo, open the window, please,’ my mother said.

‘Perhaps we should leave it closed,’ my father said. ‘It gets quite dusty later on.’

My mother frowned, and he hurriedly waved at me to do as she said.

With the window open the carriage began to smell. Home – Scotland – had smelled clean, like heather, or salt when the breeze blew straight from the ocean. And then in the spring and autumn the rain would come, hammering the earth and releasing the rich smell of peat from it. Africa smelled too much – fishy, peppery, rotting, and smoky all at once – and at first I’d thought I was going to pass out in the confusion. Now I could occasionally make something out: the sour, animal scent of a donkey, or the sweetness of the mimosa that spilled over the white fences surrounding the Europeans’ houses. Or caramel, from the sugared nuts a man was selling on the platform.