第4章 The Test Patch

A conservator cleans a wall the way a surgeon tests a patient: in the smallest area that will still tell the truth. Aloisia chose her test patch on the fifth day, and she chose it carefully. The lower right field was too significant to risk and too damaged to teach; the face of the judge was too valuable. She settled instead on a rectangle of drapery at the left of the composition, where the brown retouching lay thinnest and the surface below it looked sound in raking light. It was twelve centimeters wide and nine high, no larger than an open hand, and it would take her a full day to do it properly. She began with solvent tests, each one on a swab the size of a grain of rice. The varnish was a natural resin—mastic or dammar, she could not yet say—darkened for three centuries by candle smoke and by the soot of the house's own fires. She tried a weak mixture of ethanol and deionized water and watched the swab come away grey. She tried a weaker one, and watched it come away grey more slowly. There was a point, and she had learned to find it by feel, where a solvent lifted the grime and stopped short of the paint, where the old pigment sat under the swab untouched like a hand under a glove. Then the poultice. She laid a strip of Japanese tissue over the rectangle, brushed it flat with a soft brush, and wet it through with a gel she had mixed that morning from water and a little ammonium carbonate—enough to soften the crust, not enough to bite. The tissue went translucent and clung to the wall. She left it five minutes, then eight, watching the clock, resisting the urge to lift a corner and see. A poultice is a small act of faith. You prepare it, you set it, and you wait. When she peeled the tissue back, the grime came with it, and the wall beneath was not grey and not brown but green—a cool, mineral green, green earth laid into a fold of cloth, with a line of gold where a hem had been. She had expected nothing so clean. She sat back on her heels and looked at it a long while, and then she did the thing she always did when the wall answered her, which was to say, quietly and out loud, Well. Well, there you are. The fold of cloth turned out to be the sleeve of a figure at the left of the judge, one of the blessed, kneeling. Under the grime the green sleeve was whole. She cleaned the rest of the patch with swabs and a fine bamboo point, lifting the last of the soil from the hollows of the paint, and by the afternoon the sleeve was legible: green, gold-hemmed, the wrist emerging from it in flesh tones so faint they were almost a suggestion. Whoever had painted it had been good. Better than the provincial saint in her studio. Better, perhaps, than anyone in the valley had been in a hundred years. Vlasta brought her supper and stayed to look, standing with her hands on her hips as though appraising a wound. Some of it is still there, she said. Yes, Aloisia said. Some of it is still there. She was tired and glad, and she allowed herself the gladness. She photographed the patch from her fixed station, then in raking light, then in ultraviolet, and she logged the day in her notebook in a careful hand. Test patch A, 12 by 9 cm, figure of the blessed, left of judgment. Cleaning successful. No loss of original surface. She wrote the time. She drew a little diagram. Then she went to bed. In the morning the patch had changed. She saw it before she had her coat off. The sleeve was still green and still gold-hemmed, but the wrist above it was no longer a suggestion. There was a hand on the end of it now—small, and pale, and quite complete, the fingers slightly spread—and a hand, in a fresco of the blessed, was not a thing one could mistake or overlook. She stood in the cold church and looked at it for a long time. Then she went to her cell and fetched yesterday's photograph and held it up beside the wall. The photograph showed the sleeve and the wrist and the faint suggestion of things to come. The photograph did not show the hand. She checked the file name, twice, then the time stamp, then the backup on the second card. All correct. The photograph was the one she had taken, at the hour she had taken it, and it showed a wall that no longer existed. The wall had a hand on it now. The hand had been painted—she could see the brush marks, the modulation of the flesh, the tiny dark line of the thumbnail—and it had not been painted between the time she left the church and the time she returned, because she had the key, and the key had been in her pocket, and the church had been locked. She sat on the cold bench before the Doom and made herself think slowly. There were explanations and she knew them all. The light in the church changed with the weather; a photograph taken in one grey morning and a wall seen in the next could differ in a hundred ways, and a conservator who trusted her eyes more than her camera made that mistake once and then never again. She had been tired. She had cleaned the patch and looked at it with the pride of a long day's work, and the eye fills what the hand has uncovered, the way it completes a face at the edge of a crowd. Perhaps there had been a hand all along, under a film of soil she had thinned but not fully removed, and the overnight damp had done the rest. She found that she wanted very badly to believe this last explanation, which was a reason to distrust it. She took fresh swabs and went over the wrist again, gently, and the swabs came away clean, and the hand remained where it was, its fingers slightly spread. Then she noticed the fold of the plaster itself. In raking light, the surface of the fresh patch had a faint sheen, a faint irregularity, the kind that a wall takes on when it has been touched and smoothed—not painted, smoothed—by the flat of a hand. She put her own palm against it. The plaster was colder than the wall around it, and drier, as though something warm had been drawn across it and then taken away. She wrote in her notebook that day, under Test patch A: Re-examination, 06:40. Surface shows hand not recorded in 17:10 photograph. Possible incomplete cleaning; possible change in incident light; possible handling. No conclusion. And underneath, smaller, because she could not stop herself: the wall is being worked. She did not sleep well. At some hour before the office bell she got up and went to the church in her coat and stood in the dark before the Doom, and the patch of green sleeve glimmered faintly in the light from the cloister window, and the hand on the end of it rested, palm up, as though it were waiting to be given something. She watched it for a long time. It did not move. That should have comforted her, and did not. ---