Off 290

The cave lets you out on two feet, onto the gravel shoulder of the highway. It is dusk, and the heat is going out of the limestone. The first bats come up out of the hole in a ribbon, thin. Then more.

A woman sets a phone on a flat rock and aims it at the mouth. A broken ceramic chair leg sticks out of her pack, wired to a recorder that listens to the water in the culvert below. Her name is Julia. She says the colony takes about thirty minutes to leave. A curator named Vera Quan wants the film: one take. She wedges a folded receipt under one corner of the phone, where the rock slopes. The wind comes down the cut and lifts the receipt's edge, and lets it go.

I have to bring the recorder up out of the culvert before the water gets to it, she says. Somebody has to stay with the phone.