He knew he’d cut himself, the minute he did it. He felt a sharp pain as the scalpel sliced through his glove, but there wasn’t much he could do about it. He was cutting the dressing from a twitching stump of amputated leg at the time, and needed both hands, one to cut, one to keep the leg still. Gangrene had set in and the discarded dressing was yellow with pus.

As soon as he’d finished, he scrubbed his hands, the peeled-off gloves lying by the side of the sink like sloughed-off skin. Blood flowed from the cut. It was at the top of his right index finger, not big, but deep. He scrubbed his chilblained hands till the flesh stung, stuck a wad of cotton wool over the cut and hoped for the best.

The following day was his day off. When he reached the end of his shift he decided to walk into town and stay overnight in the room in order to be able to start work at dawn. He was nearing the end of a painting and so excited, he couldn’t bear to be away from it. Even woke up in the middle of the night and lay thinking about it, unable to get back to sleep. It was a tricky time, though. At the end of his last painting session, a week ago now, it crossed his mind that it might be finished. At any event, he was aware of the danger of doing too much. This was when somebody else’s eye would have been invaluable. Elinor’s, or better still, Tonks’s, though what Tonks would have made of it he hardly dared think.

The walk into town in the fresh, clear air, stars pricking overhead, revived him. He turned the key in the familiar lock, brimming with excitement and hope.

The room was not so powerfully full of Elinor’s presence as it had been even a week ago. Now it was the figure on the canvas he hurried up the stairs to meet, but once in the room he didn’t go immediately to the easel. Instead, he sat down on the edge of the bed, unconsciously cradling his right hand in the left. When he became aware of what he was doing, he made a conscious effort to separate the hands. He was treating it like a real injury and that was ridiculous. Children playing in a playground get worse cuts than that every day.

The easel had a cloth draped over it. Ideally, he shouldn’t look at the painting at all tonight. The gas flickered, its bluish tinge changing every colour and tone in the room. No, no, it would be a complete waste of time. But the painting seemed to call him. At last, he could stand it no longer. He jumped up and pulled off the cloth.

My God. It looked as if it had been painted by somebody else. That was his first thought. It had an authority that he didn’t associate with his stumbling, uncertain, inadequate self. It seemed to stand alone. Really, to have nothing much to do with him.

He’d painted the worst aspect of his duties as an orderly: infusing hydrogen peroxide or carbolic acid into a gangrenous wound. Though the figure by the bed, carrying out this unpleasant task, was by no means a self-portrait. Indeed, it was so wrapped up in rubber and white cloth: gown, apron, cap, mask, gloves – ah yes, the all-important gloves – that it had no individual features. Its anonymity, alone, made it appear threatening. No ministering angel, this. A white-swaddled mummy intent on causing pain. The patient was nothing: merely a blob of tortured nerves.

Extracted from Life Class by Pat Barker, published by Hamish Hamilton on Thursday (£16.99)

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