GRAND JUNCTION – Hopelessly pinned by a boulder that rolled onto his arm in a remote canyon, adventurer Aron Ralston first took a dull pocketknife to his forearm after three days, but couldn’t cut the skin.

The next day he went through the motions of applying a tourniquet, laying out bike shorts to absorb the blood and getting his gear ready for a quick getaway. He worked out how to get through the bone with his cheap “multitool”-type knife, made duller from futile attempts to scratch away at the rock.

“Basically, I got my surgical table ready,” Ralston, 27, recalled Thursday in his first meeting with the media since walking, bloody and dehydrated, out of a remote Utah canyon on May 1.

Finally on the fifth day, he summoned up technique and nerve to do what for most who followed his story is unthinkable:

“I was able to first snap the radius (bone) and then within another few minutes snap the ulna at the wrist and from there, I had the knife out and applied the tourniquet and went to task. It was a process that took about an hour,” said Ralston, slim and pale with short reddish-brown hair.

The stump of his right arm was cradled in a sling.

Ralston’s self-rescue has attracted worldwide attention, with reporters from as far away as England and Brazil waiting for him to emerge from St. Mary’s Hospital in this western Colorado city and tell his story. When he finally did, Ralston turned the tables on the media by first taking photographs of a crowded room of reporters, including seventh-grade journalism students from a neighboring school.

Ralston, who quit his engineering job to focus on mountain climbing last year, was expected to return to his parents’ home in suburban Denver by the end of the weekend.

During the five days he spent in the three-foot wide canyon, Ralston said he felt alternately at peace as well as depressed at the prospect of dying, figuring his body might be washed away in a flash flood before anyone had a chance to find it.

He joked that he often thought of drinking a margarita while he took turns standing and sitting down in his climbing harness to rest his legs. He also tried unsuccessfully tried to use the ropes to create a pulley to move the rock. Though none of those attempts worked, he said they kept his mind busy and away from despair.

Even after he performed the excruciating operation on his arm, the rest of Ralston’s rescue required skills beyond the abilities of most.

He crawled through a narrow, winding canyon, rappelled down a 60-foot cliff, and walked some six miles down the canyon near Canyonlands National Park in southeastern Utah.

By the time he encountered hikers and then rescuers, Ralston was just two miles from the nearest road.

“I’m not sure how I handled it,” said Ralston, who spent the winter climbing Colorado’s highest mountains alone. “I felt pain and I coped with it. I moved on.”

For reasons he wouldn’t explain, he withheld some details of his story. His family engaged a publicist shortly after his rescue and Ralston will not be giving any follow-up interviews soon and no interviews with the doctors who treated him will be allowed.

Ralston gave a partial answer to one frequently asked question: What kind of knife did he use? He described it as a cheap imitation of the Leatherman brand multitool, a folding device which typically has knife blades, pliers, screwdrivers and other gadgets. He didn’t give the brand, calling it “what you’d get if you bought a $15 dollar flashlight and got a free multiuse tool.”

Ralston, who made frequent references to prayer and spirituality in his news conference, said he felt a surge of energy on the fifth day, which was the National Day of Prayer.

“I may never fully understand the spiritual aspects of what I experienced, but I will try,” he said. “The source of the power I felt was the thoughts and prayers of many people, most of whom I will never know.”