“These ones,” she pulled out half a dozen of the later photographs, “these could be early Stieglitz.”

She was right. New York’s legendary photographer and art entrepreneur had produced some beautiful work, around the turn of the century, after his return to New York from Germany, that was close to Theodore Keller’s. “Did they meet?” she asked.

“Yes. Several times. I have Keller’s diaries.”

“We should mention that.” She pulled out an earlier shot, of men walking up the railroad beside the Hudson River. “Great choice,” she said. “Amazing composition.”

They started to talk about Keller’s technique. They kept talking. After an hour he’d said, “I have to be in Midtown after this. Shall we go to the St. Regis?”

He wondered if she’d turn up at the opening of the show at the Betty Parsons next week.

At the Manhattan ferry terminal, he found a taxi. Soon they were going up the East River Drive, and crossing to First Avenue. As they passed Forty-second Street, he pointed out the big new United Nations building on the right, overlooking the water. He liked its clean, modern lines. Gorham stared at it, but it was impossible to know what the boy was thinking.

“The River House is just up from here,” Charlie remarked. “Your grandmother has a lot of friends in that building.” Maybe the grandest apartment building in the city. But of course, little Gorham had no idea what that meant.

Charlie had always supposed that his son would live in the same world. Assumed it really. Until Julie went off to Staten Island. Could you breathe the spirit of the great, daring city out on Staten Island? Maybe. It was one of the Five Boroughs, after all. But would his son really understand? Would he know which were the best buildings on the Upper East Side? Would he know all the restaurants and clubs? And the intimate sights and smells of Greenwich Village, the grainy texture of Soho? Moments like this made Charlie realize how much he loved Manhattan. And it gave him a terrible pain, and sense of loss, to think that he might not be able to share the city with his son.

They turned left on Forty-seventh Street. As they crossed Lexington, Charlie pointed south. “Grand Central Station’s just down there,” he said. Gorham was silent. They reached Park Avenue and turned north. “When I was a boy,” said Charlie, “there were railway yards here. Park Avenue wasn’t so nice then. But the railway lines are all under the ground now, and Park Avenue looks pretty neat, don’t you think?”

“Yes, Dad,” said the little boy.