That he had no idea what form this catastrophe would take didn’t trouble him at present. He knew that a man may live in close proximity to things he does not yet see correctly. What he must try to do is to be vigilant and attentive to all that surrounds him, in order to find the path he should follow.

To deepen this enquiry, Ross cleaned and polished his Rayer Microscope. He set it up on a table near the fire in his lodgings and spent his evenings examining – almost at random – minute entities swept from his floor: coal dust, threads of wool from his hearthrug, flower petals, a fishbone, crumbs of bread, the leg from a dead spider.

In every case, he was disposed to marvel at what he saw through the lens. The fishbone, in particular, struck him as a thing of complex beauty, containing within its cells a peculiar pearly light. The spider’s leg, too, was admirable, like a tiny piece of medieval armour. The flower petal, so fragile and weightless, so dead-seeming, yet revealed an intricate branching of veins, as though it had the means within it to come alive again. And these things consoled Valentine Ross by their beautiful and secret complexity. He took to plucking out lashes from his eyelids, vainly hoping that the mild pain he inflicted on himself would still his mind. He placed the eyelashes under the microscope lens, examining the white bulb-like growth at each root, suggesting to him that if a lash was planted in the earth, it might begin to grow and, in due time, unfurl minute black leaves.

He knew that his thoughts were muddled – almost as if he were dreaming his life, instead of living it. But he told himself that his existence had too little of the strange and miraculous about it now that Jane had gone and his heart had nothing marvellous to feast upon. He remembered Edmund saying to him, as he’d prepared to traverse half the world, that he couldn’t be reconciled to living ‘without wonder’. And it soothed Ross to think that he could find ‘wonder’ in the detritus swept from his hearth or from a sliver of matter tugged out from his eyelid.

‘The microscope,’ he announced to Sir William, one morning, ‘reminds us that we’re born blind to the intimate secrets of everything in the world. We should perhaps make more use of it in our work.’

Sir William Adeane, it seemed, was unwilling to address this subject at present. He had been distracted in recent times. An epidemic of chest ailments had arrived in Bath. He did what he could for the sufferers, prescribing balsams and inhalations. But he was dismayed to realise that his patients didn’t have a great deal of faith in these. They kept clamouring for Jane, for the Angel of the Baths to lead them to the Hot Bath, to cure them with her touch.

‘I have a new nurse now, Nurse Peggs,’ Sir William patiently reminded them, but they were not happy. They were heard, in their distress, not to blame their adored Jane for being in London, but to blame Nurse Peggs for not being Jane, and for possessing an ugly name. ‘Square Peg’ was how they referred to her, stressing that Square Peg was not at all to their liking. And when word of this nickname reached Miss Peggs, she dismayed Sir William by stamping her foot so hard on his surgery floor that some of his surgical instruments bounced up and fell off their tray into the dust.