by Christine Temin

Different media have dominated different eras of art history: Think of painting in 19th-century France, for instance, pace Rodin. At the end of the 20th century, sculpture is enjoying a particularly fertile period, thanks to an explosion of new materials and forms and artists' willingness to work almost anywhere, with almost anything. Two shows I've seen in the last week, one in London, the other in West Newton, demonstrate how exciting sculpture can be when it swells to fit a dramatic space.

Leaves that fell in auturm from a cucumber magnolia tree outside the Chapel Gallery in West Newton are now inside it, as part of Beth Galston's installation "Leaf Dreams". The show marks Galston's debut as a member of the Boston Sculptors at Chapel Gallery group.

Not that she's a newcomer to sculpture. Her past works have often used scrims or screening, translucent materials that shape space without blocking light. She's done decor for a dance about Antarctica, sets for a dance about a bird-woman who inhabits a forest of gauzy "trees," and a "Tree/house" on stilts, rectangles of metal mesh protecting the tops of some spindly city trees and allowing visitors eye-to-leaf contact. By way of introducing her work to a new public, Galston has put models and handsome photographs of some of her past projects in the smaller of the Chapel Gallery's two spaces.

"Leaf Dreams," meanwhile, occupies the main, majestic space. Galston has worked with leaves before. She floated brightly colored ones in the pond at the Art Complex in Duxbury last summer. The Chapel Gallery project is even finer than that one, both in its delicate command of the soaring space and in its equally delicate meditation on mortality. Besides the leaves, she's included seed pods that hold out hope for regeneration.

The installation is also a dialogue between the orderliness of science and that of nature, which is less comprehensible to humans. Blown-up vellum photocopies of a tree identification pamphlet hang on the walls. Galston has also crumpled pages of the pamphlet on the floor, leaves from books keeping company with leaves from trees.

The works in the show vary enormously in scale, from a tiny circular heap of crushed and shredded brown leaves that huddles quietly in a corner to a long leaf train that slices across the floor on a bold diagonal. The train is a series of wax-covered platforms whose cargo is piles of leaves. The first piles have been obsessively sorted, with the largest leaves on the bottom, the smallest on the top. By the end of the train, the sorting goes awry, threatening to collapse into chaos, a reminder that humanity's attempts at tidying up nature can go poof! with one good gust of wind. Galston incorporates different sorts of leaves, including ones far flashier than those of the cucumber tree, and she deftly exploits their different personalities. The red leaves from Japanese maples tend to frizz; glamorous golden ginkgo leaves, conscious of their elegant fan shape, line up as if auditioning for a part on a William Morris wallpaper. But above them, on a shelf cantilevered out from the wall, is a heap of ginkgos that have been crushed, their shaped sacrificed.

The leaves' relationships with architecture are several and varied. On one wall, leaves are pinned at eye level, but they squirm away like recalcitrant toddlers, their stems stretching into the air. On another wall is a pattern created by dozens of leaves, with paper leaves filling in when the real ones run out. (This piece reminds me of Cragg's wall works, just as Galston's leaf circles remind me of the great circles of stones British sculptor Richard Long installs on gallery floors.)

In the most theatrical piece in this installation, Galston starts with a pile of leaves on the floor, then lets them ascend vertically, clinging to nearly invisible wires. The ascending leaves cast two sets of shadows, one emphatic, the other barely there, a shadow of a shadow. Finally, some leaves take flight: These are painted white, as if they've attained a purity necessary to soar to the ceiling.