WASHINGTON - I am watching John Pond build a brick wall and thinking he could charge people for the experience.

The brick in his left hand is too long for its space, so he takes a chisellike hammer and taps the brick twice. A third of it falls away, leaving a block that nestles between its neighbors, where it will stay for the next 100 years or more.

And yet that is not the most mesmerizing aspect of his work. That feat goes to the way he charges his trowel with mortar. He sidles the tool through the slop and then does a quick flick of the wrist. Somehow, the diamond-shaped trowel then holds the exact amount of mortar needed to place a three-eighths-inch joint beneath a brick just shy of eight inches long. He nails it every time with uncanny precision, and the action reminds me of a guitarist strumming away, making music effortlessly.

You might put this skill down to experience. (He has been laying bricks since 1971.) But that would fail to acknowledge the degree of Pond's craftsmanship. In April, I was invited to the unveiling of a new garden at Dumbarton Oaks, a subdued, linear space connecting the west wing of the Georgetown mansion and study center to the woodland garden beside the recently reopened Philip Johnson Pavilion.

The central feature of this area, which is called the Ondine Garden after a mythological siren, is a sloping brick path (the word seems so inadequate) that broadens into a circle around a mature Japanese maple tree before bending to a point downhill hidden from view.

The dry-laid path features two types of hard-fired brick pavers, in tones of pink and blue, and the pavers are set on edge and framed in headers, bricks that are placed vertically. The edges of the path are sinuous but so, too, are the patterns within the walkway, and at various points the path incorporates a wave motif used by pre-Columbian civilizations. (The pavilion houses the institution's display of pre-Columbian art.)

At various points, the brick is reduced to thin wedges or rounded lozenges. In tight circles, the outer edges of the pavers are longer than the inner ones, all to provide for tight joints and a seamless whole. The gradient drops about two feet along the 51-foot path, but there are no steps, just an incline that adds another challenge for the bricklayer.

I returned to the garden last week, and the sight of it evoked my initial reaction: I have never seen brickwork so fluid, so full of energy. Even to an untrained eye, this reads as a masterpiece of the bricklayer's art.

It was built by Pond and his trusty sidekick, Nathaniel Trent, who spent the winter months grading, laying a base of gravel and stone dust, and working their magic of turning something brittle into something plastic. Trent joined Pond 11 years ago, spending the first four as his apprentice.

Both say they have never been so challenged. Pond said the design left him dumbstruck. “The director (of Dumbarton Oaks, Jan Ziolkowski) thanked me in advance for carrying out the project, and I just smiled, thinking it wasn't possible to make bricks do that.” He was convinced the design would be modified to reality, and it was changed, but made even more difficult, he said, chuckling.

It consumed about 6,000 bricks, and at least one in 10 was shaped using a diamond-tipped saw. For the most challenging shapes, Pond and Trent would secure a brick with a foot and then cut it with a power saw. Doing so on the table saw, he said, would have been too perilous for their fingers.

The pathway and surrounding plantings of Irish moss and other plants in the shaded glade were the work of landscape designer Jane MacLeish, who created the garden in collaboration with the staff at Dumbarton Oaks.

It is not open to the public, except during occasional symposiums in the nearby Music Room, but it can be well glimpsed from the adjoining North Vista garden, which is open (www.doaks.org).

Pond has undertaken other projects at Dumbarton Oaks, including expansion of the Music Room stone terrace last fall.

“Having been here a lot of years, I just say I belong here because this place is almost as much about the hard-scape and masonry as it is the plants,” he said.