"Charles Gleyre: 1806-1874," at the University of Maryland, is a revisionist exhibit. It topples old assumptions. It contends, and partly proves, that the Swiss-born Salon painter has been given a bum rap.

Gleyre was no genius. It is true that he filled his paintings with mighty muscled warriors and naked soft-skinned nymphs. The pictures that he left us, ripe with sex and spectacle, illustrious with Latin names and mythological allusions, are pictures of a sort we've been taught to laugh at. These are academic pictures, pictures that our day tends to view with scorn.

It is the academic painter, Gleyre, for example, who plays the role of bad guy in conventional accounts of the birth of modern art.

The Salon painter of the time is usually cartooned as a foe of innovation, a stickler for rules, a money-grubbing, medal-seeking toady to the tastes of the bourgeoisie. In the fight for modern art, so the textbooks tell us the avant-guardists were heroes, the rear-guardists were wrong.

Charles Gleyre was both at once, both conservative and radical, as fond of tradition as he was of the new. Much of 19th-century art seems to pivot around his studio. He was a painter in between.

James Abbot Mcneill Whistler, Pierre Auguste Renoir and Claude Monet, innovators all, were among his students. They gave the old Gleyre respect and deep affection.But he refused to take their cash. Orphaned at the age of 10, Gleyre nearly starved when he first studied painting. Later he tried to ensure that poor young painters be excused the suffering he'd known.

His politics were of the left.He hated the Napoleons. As an act of protest, he early stopped exhibiting in the French Salons where he'd had much success. When offered the Legion of Honor, Gleyre turned it down.

In the early 1830s, he went to study art in Rome, as did many other painters of the day. But while most of them returned to France, Gleyre kept on going. As a paid companion to a young American, John Lowell Jr of Boston, Gleyre went on to the Near East, to Izmir and to Cairo, then up the Nile to Khartoum. In those days before photography, he was hired as an artist to make portraits of the natives, the ruins and the wonders Lowell might encounter.

A selection of the clear, accurate, romantic pictures he produced is included in this show. It was not an easy journey. There were brigands on the roads and storms on the high seas. Gleyre, in the Sudan, took a Nubian lover and, perhaps from her, contracted an eye disease that blinded him for 10 months.

Most early modern artists, the impressionists, for instance are today admired for the new ways they used color. Gleyre's innovations are, instead, apparent in what he chose to paint.

His imagery is bracing, fantastical and fresh. His pictures seem designed to give the viewer an adventure. We see the Queen of Sheba here in a daring little sketch arriving in great splendor in a chariot drawn by two giraffes. Arabian horses leap from cliffs. A domesticated Hercules surprisingly spin wool; a pterodactyl glides above a prehistoric swamp; we see in Gleyre's art naked women, snakes, turtles, severed heads. Nero views the corpse of his murdered mother. She has the body of a pinup. Gleyre's subjects are not dull.

Gleyre taught his students to be willing to take risks, though he himself appears to have left less to experimental painting than he left to other sorts of art. Monet and Renoir may have been his students, but his true heirs seem to be such painters of exotica (tinged with the erotic) as Alma-tadema and Maxfield Parrish, and such 20th-century entertainers as Walt Disney and Cecil B. DeMille.

A curious figure, Charles Gleyre. He drew well and he taught well, yet one leaves his exhibition with more affection for the man than for the art he left us. This is his first large show in the United States. He will not get many more. The exhibition opened in February at New York University. A catalog essay (accompanied by infuriatingly tiny illustrations) was written by William Hauptman, an assistant professor of art history at the University of Maryland. The Gleyre show will remain on view there through May 2.