Jerry Clapsaddle's abstractions are pictures about patience. The colorfield paintings in his little retrospective, "Some Paintings from the Past Ten Years" -- now at the Art Department Gallery of Catholic University -- demand a kind of calm. You can't grab them, you must graze them. The viewer who attempts to see them all at once will not see them at all.

Clapsaddle applies, in overlapping layers, some 10,000 little brush strokes -- horizontals, verticals, diagonals and arcs. Were he rushed or restless, the building of these pictures, the weaving of these color-tweeds, would no doubt drive him batty. But his works are never frazzled; instead, they suggest contentment and the pace of daydreams. They are mantras for the eye.

Clapsaddle repeats himself. But in certain repetitions -- the weeding of a garden, the spinning of a prayer wheel -- are paths that lead to freedom. In time these paintings blossom: Each one seems to summon to the surface not one grid, but many grids, overlapping rhythms and patterns that are multiplied. The mind drifts for a while, then focuses on detail, then drifts on again. The most surprising thing about them is how much there is to see.

These are color paintings, field paintings, pattern paintings, too. These receptive, shifting pictures accept all sorts of labels. But though they are abstractions, and though they seem to be entirely obedient to geometry and number, they sometimes manage to suggest flowerings and figures, the jazzy flash of deco art, the seasons of the year. "Winter Packet" (1975) speaks as much of melting ice, pale winter sunbeams and flurries of fresh snow as it does of grids. The squares and arcs and thumb-length lines gathered at the center of a painting titled "Mom's Remind" (1979) conjure up what seems to be the shadow of a child with his arms outstretched.

Clapsaddle, who shows with Nancy McIntosh Drysdale, is an assistant professor at the University of Maryland. Though he has learned much more from the watercolors of Cezanne than he has from Matisse, and more from Jackson Pollock than from rugs or Turkish tiles, he has been grouped, of late, among the pattern painters, a factor that has not dented his career. He was just given a painter's fellowship by the National Endowment for the Arts. His show closes Sept. 18.

Helena Dunshee de Abranches Townsend, a highly competent and euphoniously named sculptor from Brazil, is showing recent works of carved wood and cast bronze at the Organization of American States. The viewer's admiration for her handsome, polished objects would be greater if they did not look so much like Brancusi's.

If one must have a master, one might as well select that remarkable Romanian, but Townsend is too deeply in his debt. Among the well-made works here are her versions of his "Leda" and his "Bird in Space." The bases of her sculptures, too -- those stacked cylinders of wood -- recall those of the master. It is, no doubt, a treat to imitate that genius, but no one can compete with him and expect to win. This is her first show in the United States. One hopes she will have more. It closes Sept. 22.