The statue – large, broad and solid, a thick pedestal with three dragon heads – was cut from grey stone and rang with a dull soft note like a muted bell. It was a week before I knew I had been sleeping in its shadow. The day had begun with the family singing in the room below – a Lutheran hymn, sung at the dragging pace of a dead march. Lying in the attic, prevented from sleep, I followed its halting progress, disturbed by the defeated tone and odd emphases. In the intervals between lines, I could hear the rumble of Ama Darius's voice. What did he mean by such a performance? In a village of staunch churchgoers, his family spent Sundays at home. Yet in our conversations he had been at pains to impress me with his piety and with the great struggle it had cost him, as if the whole burden of Nias, its poverty, its violent tribal past and its uncertain salvation fell upon his shoulders.

Dawn smells of woodsmoke and pig dung drifted in. Above the dirge, the sounds of morning: the scraping of a twig broom, the clunk and splash of a streaming well and women's voices, busy before the heat built up. In the gabled attic the air was cool, dank with mould. The shapes of night grew distinct: heaped sacks, wicker fish traps, lanterns, rolled matting. And above the lumber, quite suddenly there it was, pale in the vestry-like gloom: a three-headed pedestal, mount of a chieftain. Out of the shadows it loomed, a stone Cerberus.

But what was it? In the half-light the faces had an air of newness, as if the statue had sprung ageless and unblemished from the past. The jutting heads were unfinished, the jaws mute. In villages upstream I had seen similar monuments, scuffed and rain-worn. Here was their prototype.