Zal Chapgar, a star athlete and 2003 graduate of Wissahickon High School, took his life on Monday in the most public of places, leaping from an upper floor of the Loews Philadelphia Hotel and landing on the sidewalk at 12th and Market Streets.

Passersby who gathered around his crumpled body and tried to make sense of his death knew nothing of the young man so full of promise.

But Chapgar's talents and passion for life were evident yesterday as friends and family members were left to deal with the anguish of losing a 23-year-old they had desperately tried to save.

He had been suffering from depression and mental illness for the last year, his family said. Because he was an adult, their ability to help him find the treatment he needed was limited.

"It was so hard for us to get him help," his sister, Jasmine, said. "Everything was a struggle."

Police are calling his death a suicide.

Chapgar was a champion wrestler and played lacrosse and football, and displayed a competitive intellect to match. His friends recall being dazzled by the heady concepts he'd want to explore and the irrepressible drive with which he pursued them.

He read Descartes and Aristotle for the pure pleasure of the journey. "And he scored 1580 on his SATs," recalled Emily Kohler, one of Chapgar's childhood friends. "He would always challenge you to think, and was absolutely one of the smartest people I've ever known, or probably ever will know."

Kohler and Chapgar belonged to an inseparable group who would hang out every day after school, playing basketball and building forts.

"We'd pitch tents in my backyard," said Frank Scarafone, another member of the Little Rascals-style gang. "And we'd run a thousand extension cords to the house so we could set up TVs and play video games. Then we'd stay up all night drinking soda until we passed out from all the caffeine."

Since graduation, friends had seen Chapgar sporadically, but had lost touch with him during the last year and knew little about how his mental illness had progressed.

Yesterday, before the funeral, a few of those friends gathered in Scarafone's kitchen, across the street from Chapgar's yellow split-level, to reminisce.

As a competitor, they said, Chapgar had more moxie than his moderate size might have warranted. "I had at least one foot on him," said Jeff Perrone, who is 6-foot-5. "And I'd drive him crazy when we played one-on-one basketball. But he still caught on me sometimes."

"He was a little guy, but he'd take on anyone," said Scarafone. During a wrestling match, when Chapgar was up against a boy "easily three times bigger than him," Scarafone said, "he got a bloody nose, pulled himself together and then beat the guy."

At times, they said, Chapgar's aspirations would exceed his abilities. A particularly memorable example was the time Kohler's parents were away on vacation and the friends were in the house. "Zal said he could run a seven-minute mile and to prove it, he turned on the treadmill to the maximum, then got on," Perrone said. "He went flying, flying into the wall. His foot went right through the drywall."

When the Kohlers returned, Chapgar greatly impressed his friends with his honesty. "He fessed right up," said Perrone. "Then we all spackled the wall and repainted it."

"I was convinced this kid would be a lawyer," said Steven Morris, his former Cub Scout master. "He could debate the color of a brown bag. And win."

If the formula for personal disaster requires dysfunction and hardship, neglect and ignorance, then how does it happen that a boy like this ended up like this, with such a cruel ending to his too-short life? Even if those answers were the public's business, they were not within reach yesterday.

Hundreds of Chapgar's young friends and members of his family and his Zoroastrian community crowded into a small funeral home in West Norriton to mourn.

Chapgar's father, Jay, is an architect. His mother, Kerban, is a teacher. Jasmine is their older child. They sat at the front of the room near the open casket, with a red poinsettia beside it.

Their religion has its roots in ancient Persia, and the service consisted of two men dressed in white reading from prayer books and chanting in an ancient language for a half-hour. The men in the room wore velvet skull caps; the women head scarves.

At the conclusion of the service, Kerban Chapgar, with a gauzy white cloth draped around her gray hair, stood and spoke briefly of her son's "short, sad life."

"He always believed," she said, "in a better world."