Walter Gay spent more than 40 years painting empty rooms.

It sounds creatively impotent and vaguely comic, like something out of “Zelig” or P.G. Wodehouse, but in practice it turns out to be subtly interesting, if not fascinating. Gay (1856-1937) and his work are the subject of an exhibit now at the Flagler Museum in Palm Beach.

He came from some money - his father was a Massachusetts state senator. When Gay demonstrated an interest in art, the family agreed to support him for three years while he studied in Paris. After the three years was up, it was time to come home, but Gay had fallen in love with Paris and decided to stay. He had exhibited in French salons and done well, become friendly with Toulouse-Lautrec, John Singer Sargent and Thomas Eakins.

Helping him along in his path to independence was his marriage to Matilda Travers, whose family had serious money - her father co-founded the Saratoga Race Track. Gay’s marriage gave him entree to the highest levels of French society, and, with time out for trips back to America to see friends and family or fulfill occasional commissions, he spent the rest of his life in Paris.

Gay’s early work, of which there are a couple of examples in the exhibit, focuses on peasant and lower middle class life and emphasizes the nobility of toil, much in the approved manner of Millet. The paintings are competent but unremarkable. What Gay already does well is light - its clarity, how it falls. But there are some strange tics - in one painting, of his wife reclining on a chaise lounge, he can’t be bothered to create a face for her - it’s a tan blob.

There are two possibilities - either he wasn’t interested in faces, or he realized very early on that he didn’t do them terribly well and didn’t care to get better.

He began painting interiors in the 1890s and never went back. There’s an odd, almost literary tension in his work. Many of the paintings document his own homes and studio, although as his reputation increased he also was hired to paint the rooms of other friends - the exhibit has some very nice paintings of the Henry Frick mansion in New York. But the documentary overtones are overwhelmed by the fact that his paintings regularly re-arrange the actual items in a room; Gay shifted furniture or sconces in order to make them more pleasing to his compositional sense.

The absence of people would seem to be more of a problem than it actually is, because Gay contrived to make the rooms look lived-in, as if the inhabitants had just strolled out of the frame. In “The Luncheon,” a dinner table has a crumpled napkin and the silverware rests on a plate; in “The Front Parlor,” a living room has a rumpled rug.

Gay’s work is very loosely painted, closer to Monet or Cezanne than the carefully detailed work that might be expected of someone doing what conceptually amounts to architectural painting. Matilda Gay called her husband’s work “poems of interiors,” and at their best they are beautiful. In particular, there’s his 1926 portrait of Edith Wharton’s bedroom, inscribed to the writer, with two dabs of orange for accent and her writing desk in the foreground corner. Rooms need people, but Gay made do with light and its effects, which was probably wise, as his perspectives in the occasional outdoor scene seem too abrupt.

By the time of his death, Gay must have seemed comically hermetic to the art world at large, but amongst critics his status was still secure. After he died, The New York Times hailed him as “the dean of American painters in Paris,” and there was a memorial exhibit of his work at the Metropolitan Museum in New York in 1938.

Matilda stayed on in their chateau after it was occupied by the Nazis during World War II. She died in 1943, but nobody knows if her death was natural or if the Germans nudged her into eternity.

Insulated by money, Gay was free to focus on his own little corner of the world. Proust, who knew the value to be had by gazing intently while staying in one’s room, would have approved. The exhibit is worth your time.