The dam.
Several days later, an unusual roar shattered the morning calm of the river valley.
The sound didn't come from the construction site of the eastern spillway, but from further upriver, in the direction of the canyon.
It was unlike the crisp ring of hammers striking stone or the resonant calls of the laborers. Instead, it was a dull, focused BOOM that echoed distinctly, sounding off at intervals. Each blast made the air tremble and seemed to send a low thrum through the very body of the dam.
At that moment, Arthur was leaning on his oak cane, inspecting the mortar joints of a newly built retaining wall on the eastern construction site.
When the first BOOM resounded, his hand, spotted with age, instinctively tightened its grip, and the head of his cane tapped against the gravelly ground.
He cocked his head, his cloudy yet still sharp eyes narrowing as he gazed upriver toward the canyon, which was shrouded in the morning mist.
