The New Yorker:

A new kind of prosthetic limb depends on carbon fibre and computer chips—and the reëngineering of muscles, tendons, and bone.

By Rivka Galchen

Hugh Herr, the director of an M.I.T. laboratory that pursues the “merging of body and machine,” grew up in a Mennonite family outside Lancaster, Pennsylvania. He and his brothers—he was the youngest of five children—often helped their father, a builder, lay shingles, install drywall, and strip wires. During the summer, the family visited places like Alaska and the Yukon in their camper van, and the kids frequently set out alone to hike and rock climb. “When I was eleven, I was this climbing prodigy, climbing things most adults couldn’t do,” Herr told me. “When I was fifteen and sixteen, I started climbing things that no adults had ever done. And then, when I was seventeen, the accident happened.”

Rock climbers call bouldering moves “problems,” and the most difficult section of a route is the “crux.” The young Herr spent days imagining difficult ascents, plotting a path across slots, cracks, and overhangs as one might work through a complex question in geometry or physics. Then he would go out and become the first person to ascend, say, a rock face on the Shawangunk Ridge. (By tradition, the person who makes the first ascent gets to name the route. The chosen names are often kooky: Moby Grape, They Died Laughing, Lonesome Dove, Millennium Falcon.) Herr sometimes did what’s known as free-solo climbing. “I’ll never forget the day I climbed two thousand feet without a rope,” he told me. “All your sensations are heightened. It’s a remarkable feeling of one’s physical control and power.”

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