A handsome new gallery, Addison/Ripley, has just opened in -- of all places -- a former carriage house at the end of the alley behind the Phillips Collection. The proprietors are Chris Addison, a Smithsonian exhibits designer, and Sylvia Ripley, daughter of Smithsonian Secretary S. Dillon Ripley. They plan to spotlight artists who have not yet come within dreaming distance of papa Ripley's museums on the Mall.

The new gallery is off to a good start with the works of abstract painter Michael Smallwood, 31, who is deeply involved in finding his own way and doing so with intelligence and honesty. In large oil-on-canvas paintings, Smallwood does variations on the same format: pyramidal forms set against solid, scumbled backgrounds, the pyramids sometimes inverted, sometimes tip-to-tip, sometimes joining together into rhomboid-like architectural forms that settle down at the bottom center of the canvas -- or almost at the center. Though all at first appear to be symmetrical, they are all just off-center -- sometimes amusingly so, sometimes so you'd hardly notice -- "to add tension," the artist explains.

But what ultimately brings these paintings to life, when they come to life, is the lyrical color, which has been applied in transparent layers. They sometimes recall the pastel palette of Jacob Kainen, for whom Smallwood worked as a printing aide after graduating from the University of Maryland. At their best, these works are meditative and have a strong presence; at worst they are derivative. Several of the best works in this show are to be found among the smaller oil pastels on paper. The show continues through Oct. 21, and the gallery is open Tuesdays through Saturdays, 10 to 5. Thorpe at Barbara Fiedler

Two years ago, Washington artist Hilda Thorpe simultaneously introduced a new suite of work at two suburban galleries: Plum and Gallery 4. They were sweeping, frothy, wall-hung sculptures made from ordinary white gauze stiffened with handmade paper pulp -- a medium the artist had discovered by accident, and from which she had wrested a broad range of expressive possibilities, the best of them in pure white.

In her new exhibition at Barbara Fiedler Gallery, 1621 21st St. NW, Thorpe is showing the fruits of her continuing explorations in this medium. The emphasis is on the use of color -- something over which Thorpe has an instinctive full command. The verdict, however, is inescapably the same as it was two years ago: While the fragile, filmy, all-white works such as "Cloud Spill" continue to conjure the essence of cloud and sea, the works in color -- particularly the large ones dyed in rich, deep hues -- still don't work because the tackiness of the gauze is so hopelessly at odds with the richness of the color. Thoughts of paint rags cloud the mind.

Handsome results can ensue, however, when Thorpe keeps the colors pale and the scale down, as she does in several free-form works called "Pieces of Sky." A promising new tack has been taken in "River Space," a piece made of handmade paper with strips of embedded bamboo. The major sour note is a ludicrous ensemble which combines a Thorpe painting (she is simply not a very interesting painter) with a white gauze and paper piece strewn on the floor below. Even the best artists need editing, a service usually provided by their dealers. The show closes Oct. 16, and hours are Tuesdays through Saturdays, 11 to 5. Fondo del Sol: Hispanic Artist

To make better-known the work of the growing numbers of good Hispanic artists now at work in the Washington-Baltimore area, Fondo del Sol, 2112 R St. NW, has organized its first juried show, "Other Voices." It's a good show -- though not a great one -- and includes the sculpture and photography of seven artists chosen from the scant 28 who submitted. One major drawback is the exclusion of any artist who had previously shown at the gallery; another is the exclusion of painters and printmakers, whom, we are told, will be shown in a separate show. But since Fondo del Sol opened in 1977, they've surprised us with so many good new artists of Hispanic heritage that we've come to expect revelations considerably more formidable than those made here.

While overall quality is high, the most challenging of the new artists presented here is San Juan born Maria Velez, who makes evocative sculptural assemblages that warrant a broader look. Photographer Frank Espada, director of the Puerto Rican Diaspora Documentary project, has entered provocative images from that worthy series, while photojournalist Marcelo Montecino is showing powerful images from Nicaragua. The show will continue through Monday, noon to 6 each day, including Sunday.