By this time, the apex of the arch and its left-hand side were almost uncovered. The notabilities had been given notable treatment; he'd even used gold leaf on the clothes and, astonishingly, cinnebar to gladden lips and cheeks of the supporting seraphic cast. In fact, here and there, the willingness of whoever had put up the money had gone to his head and he'd been staggeringly prodigal with the expensive reds and almost protibitively priced leaf. But once he'd begun (as I was now beginning) on the damned souls dithering on the brink of the flames or hurtling headlong into them, he'd switched to the cheap stuff, red earth and iron oxides. Even so, this concentration of similars saved it from odious comparison with the no-expense-spared Michael and his bloodthirsty furnace-hands. And he'd compensated too by his vigorous treatment: he'd really warmed to the work. Up at the top he'd done an extremely competent job, well, more than that, because he was master of his trade and couldn't have done anything but a great job. But now, coming to this lower slope, he'd thrown in the lot - art and heart.

So, each day, I released a few more inches of a seething cascade of bones, joints and worm-riddled vitals frothing over the fiery weir. A few wretches were still intact. To these he hadn't given a great deal of attention; they were no more than fire fodder. All but one. And he, I could have sworn, was a portrait - a crescent shaped scar on his brow made this almost certain. His bright hair streamed like a torch as, like a second Simon Magus, he plunged headlong down the wall. Two demons with delicately furred legs clutched him, one snapping his right wrist whilst his mate split him with shears. It was the most extraordinary detail of medieval painting that I had ever seen, anticipating the Breughels by a hundred years. What, in this single detail, had pushed him this immense stride beyond his time? So there I was, on that memorable day, knowing that I had a masterpiece on my hands but scarcely prepared to admit it, like a greedy child hoards the best chocolates in the box. Each day I used to avoid taking in the whole by giving exaggerated attention to the particular. Then, in the early evening, when the westering sun shone in past my baluster to briefly light the wall, I would step back, still purposefully not letting my eyes focus on it. Then I looked.