It just hung there for a minute, a globby, dangling blob, then snapped, trailing along a spit stringer like the tail of a comet. It issued from the crimson lips of a kid with black hair. His chin rested on the railing spanning the bridge. He was maybe ten. And the temptation must have been great. I know how it is.

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So out it came, stringing out, pulling and stretching the viscous limits of saliva, hanging there in a white froth. It snapped and hurtled down. The kids squealed and fled. “Got ’em,” I heard one say. But the blob just smacked the water a few feet away with a gentle pop, like so many other belches rising from the river bottom.

Under the bridge, out of the sun, I held us up, thinking to thwart the little monsters waiting to get us as we came out the other side. Pigeons nestling in their doo, caked up on the ledges of structural iron, discussed who we were and what were we doing there.

“Sounds good. You take it easy,” I say, righting the boat and pulling forward. I don’t worry too much about the spit blobs anymore.

“I’ll pull over to the bank and you can turn around to face me,” I tell him. When the bow bottoms on the mud, river rats spring away.

There are boat docks here; abandoned concrete pillars with sculpted cornices rising from the murk; molding oak doorways that once opened to accept landing parties; a cascade of steps wide enough to take 20 promenading shoulder to shoulder. A spindled banister of whitewashed cement sweeps upward then forms a balustrade on an enormous patio absurdly out of place. Nero was here. Across the way a swatch of forest squats lacking a better home. An old pump house stands ready for the Roman senate to convene. And everything, every carved fissure and cracked wall is covered with spray-paint cryptographs, urging us: LVst…Dimo…Wreck…Flee…Flee…Flee!