At 4:38 in the afternoon, one lamp glowed.

A rotary phone rang in the office behind her. The door’s painted lettering read DR. MERCER—GENERAL PRACTICE. Inside, an examination table waited beneath a paper roll yellowed by seventy years. Lena lifted the receiver.

“Hopkins exchange,” said a woman’s voice. “Which party?”

Lena looked through the glass. The switchboard was empty. “There’s been a mistake.”

“There will be,” the operator replied. “At 4:52.”

The line went dead. In the corridor another telephone began to ring, then another: the lawyer’s office, the advertising agency, a room whose sign had been removed. Each caller spoke from July 1952. A secretary complained of a crooked picture frame. A doctor asked whether the floor was moving. A boy said his father had gone downstairs and the stairwell would not give him back.

Lena checked her watch. 4:47.

She descended toward the lobby, but the stairs ended at the third floor each time. Outside the windows, modern traffic had disappeared. Chester Avenue lay under a white summer glare, filled with cars curved like beetles. People on the sidewalk had all stopped to stare east.

The building gave a low animal groan.

At 4:51, every phone rang together. Lena ran to the switchboard. The lamp marked EXT. 1952 flashed red. Without knowing why, she inserted a cord.

“Hopkins exchange,” she said. “Which party?”

Her own voice answered from the line. “The woman on the third floor.”

The first jolt threw her from the chair. Walls rippled. Cabinets spilled ancient files whose pages were blank except for her name. Through the operator’s headset came hundreds of voices calling numbers, mothers, saints. Lena crawled beneath the switchboard as plaster rained around her.

Then someone touched her hand. A boy crouched beside her, translucent in the dust. “You have to keep the line open,” he said. “It’s the only way we know when it ends.”

For nearly a minute she held the cord while the building convulsed around two different years. When silence returned, the boy and the old street were gone. Her watch read 4:53. In the lobby, the foreman swore there had been no tremor.

The switchboard was removed the following week. Lena watched the crew carry it outside. One cord trailed behind, though every cable had been cut.