Robert Shelton had never seen the floor of what he always called the sugar house until the day this spring when he returned to the Domino refinery. In the 20 years he worked in its char house, the kilns blasting the temperature up to 140 degrees year round, the mounds of unbleached crystals had never dipped below the seven- or eight-foot mark.

Now he could see it was all gone, and the metal beam at the plant in Williamsburg, Brooklyn, that used to mark the sugar’s high point — it was still caked, here and there, with clumps at least a decade old — came up only to the white sphinx’s neck, maybe her ear. She was that big.

“It almost talks to you; it’s alive,” Mr. Shelton said on Tuesday. “Something just comes over you.”

He was talking about “A Subtlety,” the massive sculpture by the artist Kara Walker, a sugar-coated homage to African-American slave women and to the slave laborers who built the 19th-century sugar trade.

The installation is to close on Sunday. The closer the day gets, Mr. Shelton said, “the sadder I get, because after this, I can never come back here again.”