The emperor has no clothes, and Sheila Isham's paintings are not what they're cracked up to be.

That is the only message to be gleaned from the show now at Addison/Ripley Gallery--a survey of Isham's work from the past dozen years. The point is underscored by a series of new paintings that set a new qualitative low.

Isham is a serious painter, no question about that, so the argument here is chiefly with the social forces that propelled her into what now seems a disproportionately grand--and as yet clearly unwarranted--reputation. She did not contrive it: In fact, she first became something of a heroic figure here when, in 1972, she lost most of her paintings in a devastating studio fire on F Street. Oddly, some of the paintings originally had a smoky quality. It made good copy.

Since then, Isham has continued to live here and abroad, as the wife of an American ambassador, and has exhibited frequently in Washington, where she reached something of a pinnacle last year with a show at the National Museum of American Art. That show, titled "East and West: Painting/Poems by Sheila Isham," contained calligraphic works on paper inspired by T'ang dynasty poems. They effectively illustrated her special blend of Oriental philosophy and Western painting traditions.

The Addison/Ripley show begins where the works in the museum show left off, in 1971, when Isham began to make large airbrushed paintings consisting of allover billows of color--sometimes pale, sometimes lurid--from which floral or orchid-like forms emerge. On view in the first room, these paintings number among them a few survivors from the fire.

From there, the work takes a big step forward in the nearly all-white paintings from 1975, in which the billowing clouds of color and floral forms are more subtle, and thus better able to express the oriental, contemplative mood the artist seeks. If this survey is true to its subject, these "white" paintings remain Isham's strongest to date; for what follows goes from bad to worse.

And the newest work is the worst: gigantic canvases in which the airbrushed clouds of colors return, but now as mere background to a scattering of brushed-on calligraphic doodles. Upon prolonged groping, the viewer will ultimately discern among these doodles a head here, a bouquet there, garlands everywhere, but what does it all mean? The answer is these paintings have no meaning--or other redeeming aspects--whatever. Ironically, they are all from a series titled "Cosmic Myth."

The stock market must find its bottom before it can rise again; perhaps Isham will do the same. Meanwhile, her show continues at Addison/Ripley, 9 Hillyer Court NW, through April 6; hours are Tuesdays through Saturdays, 11 to 5. A show of her works on paper is concurrently on view at Phoenix II, 1875 I St. NW.

William Shirley Portraits

The spookiest show in town is surely William Shirley's bizarre gallery of portraits now on view at Gallery K, 2032 P St. NW. And if you get the feeling that these paintings are turning their heads and moving their eyes, tracking you as you walk around the room, you're right.

Based loosely on famous portraits by Titian, Rembrandt and others, these images recall the seemingly three-dimensional photographs sometimes used on the covers of children's books. Shirley's unusual technique is not unrelated: He paints upon layer after layer of clear acrylic resin, changing the position of the head and eyes ever so slightly as he goes, ultimately giving the viewer the sense of a multiple image.

Though the paintings recall the work of Francis Bacon, and are chiefly curiosities, they do have their startling aspects, notably in the beards, hair and fur, which are built up from tiny brush strokes and seem uncannily real. The gallery is open Tuesdays through Saturdays 11 to 6. The show continues at 2032 P St. NW through April 6.

Pencil Drawings by Folsom

Also showing at Gallery K are meticulously rendered pencil drawings by Fred Folsom--all nonstop, unspecific mayhem and hilarity of the sort we have seen before in his paintings. In "Mother's Day," for example, we have a chubby middle-aged man about to present a rose to his aged mother, who stays in her rocking chair but shields her eyes from her son, presumably because she doesn't like seeing him stark-naked.

Preposterous juxtapositions are Folsom's chief device, but what holds the viewer is the utter outrageousness of the scenarios they suggest. How, in "The Encounter," for example, did the laughing nude woman (leaning against a desk) and the obese clothed workman (sitting on a chair) ever get together in this empty office? We'll never know, but neither will we soon stop wondering. Folsom's show, also at 2032 P St. NW, continues through April 3; gallery hours are Tuesdays through Saturdays, 11 to 6.

Prints at Women's Arts

Each year, the Washington Women's Arts Center sponsors a print show, and year by year it gets a little better. "Printmakers IV" was selected by Robert D'Arista, one of the best painters in town, so the emphasis on craftsmanship comes as no surprise. Monotypes continue to be a popular genre, and some of the best works in the show--notably Rosaline Moore's painterly "Still Life with Striped Mat" and examples by Marguerite S. Richards and Carrita Smith--are in this medium. Marcy Wolpe's serigraph of a cosy, imagined interior and Aline Feldman's woodcut "Yellow Sky" are other standouts. The show, located at 1821 Q St. NW, closes today. Gallery hours: 11 to 4.