"TWO HORSES IN A CANYON," Conrad Buff titled his painting that hangs in the Nora Eccles Harrison Museum of Art. The Swiss-born house painter made his first trip to the desert Southwest in 1907 and from then on he was a landscape painter.

English Professor Chris Cockinos has just turned us loose with the instructions: "Walk into the painting if you have to. Open up and investigate. Question your motives."

Fourteen students have enrolled in his writing class, and each one of us is now parked in front of a painting or photograph or porcelain pot that has spoken to us for some inexplicable reason. The museum is silent except for the scratch of pen on paper, the turning of pages in notebooks. The cell phones have been turned off and shoved into backpacks that have been left behind in the lobby cloakroom. If there is anything to add to the grocery list for tonight's manic shopping run, it will have to wait.

Black boulders as big and blocky as skyscrapers frame the foreground of Buff's painting. In the distance, a fractured ridgeline and another beyond it support towering mesas. On the ride side of the canvas, two black horses graze beside a pond, their shadowy presence the only suggestion of human activity other than the horizontal strip of irrigated green between ridges. The shock of emptiness is muted somewhat by the pale blue sky in the background. more