Coats were piled atop the desk from which David L. Lawrence once governed, and Bob O'Connor, delighted to be latest in a long line of mayors of Pittsburgh, spent his first day in office greeting an even longer line of well-wishers.

	Steve Mellon, Post-Gazette After his inauguration yesterday, new Pittsburgh Mayor Bob O'Connor reaches down to shake hands with former Mayor Tom Murphy. Click photo for larger image. Related coverage Photo Journal: Bob O'Connor becomes Pittsburgh's new mayor Ravenstahl re-elected City Council president

"Move all that junk so they can put their coats there," Mr. O'Connor told aides. They swept away the new nameplate that says "Bob O'Connor," a small plaque declaring "My #1 Priority is the people of Pittsburgh," and a Medieval-looking wooden mace with 16 spikes that suggests someone out there is in for a surprise someday. On went the coats. Davey Lawrence's old desk suddenly resembled a bed on Thanksgiving.

Someone asked him if he felt like Andrew Jackson -- a president famous for crowding his office with anyone who could walk in.

"I feel like Bob O'Connor, Mayor of Pittsburgh," he said.

On a day that threatened rain and promised change, Pittsburghers by the hundreds crowded through metal detectors at the City County Building, ate their way from the front entrance all the way down to a bank of elevators that lugged them to the fifth floor to meet the 58th Mayor of Pittsburgh. Mr. O'Connor, flanked by a family that resembled the United Nations -- black grandchildren, a Jewish wife, a Catholic priest of a son -- gripped, grinned and prepared to govern as worried aides tried to get all the visitors past him before his first term ended.

"Start smilin' back here. It'll go quicker," volunteer aide Frank Rende told visitors in the middle of the line. They laughed.

The building, maybe even the entire day, smelled of coffee, sausage, and stromboli, with caterers encamped on two floors. Someone asked Mr. O'Connor if he'd eaten yet.

"How's that working out down there?" he smiled.

It was working out this way: several hundred, maybe even a few thousand, people from all walks of life and several branches of government were bumping shoulders and moving like molten lava through the arched hallway downstairs. The pattern was to clear the metal detectors, edge toward the first table and graze until a full-circle that began with tater-tots and meatballs ended with bagels and phad thai.

"It's a free lunch, but you got to pay for it," said Debbe Brown, who came in from Baldwin to watch her aerobics instructor's husband join the new administration. Ms. Brown was talking about the physical cost. The crowd pressed so heavily against her she couldn't have fainted if she wanted to, at least not and fallen down.

As she chomped on a bagel, waiting to see where the human current would carry her, Ms. Brown heard a shout over her right shoulder.

"Michael! Michael! Just take my hand!" A woman reached past her and a hand popped out from the crowd.

"S'cuse me," a voice said as a head, then a shoulder, then the rest of a man, squeezed out of the wall of torsos.

The giant circuit of plenty took place in full view of the ordinarily bustling City County Building snack bar, whose manger, Nick Mastros, wrote off yesterday as a bit of a contribution to the new mayor's inauguration.

"No, I don't anticipate us doing much business today," Mr. Mastros said. He served coffee. For free. Even at that, the competition was fierce.

Outside, for instance, on opposite corners of Grant and Forbes, two vendors dispensed free coffee to inauguration-goers.

Early in the day, worries began to hover about whether the seats would fill and, if they filled, if their occupants would depart soaked and frozen. Rain drizzled tauntingly and the mercury seemed to drop with a sigh. Five minutes before the program kicked off with music from the Perry Traditional Academy band, it was still possible to count the people in the sea of chairs and stands blocking Grant Street: 59.

The first guests to arrive were an octet of young adults from Conroy Education Center in Manchester.

"I thought it would be good for them to see who our new mayor is and who's running the city," explained Bill Wells, a teacher.

The students waited patiently in the cold as someone who was not about to be the new mayor, Joe Weinroth, the woebegon Republican who was pitted against Mr. O'Connor in a city that has not had a GOP mayor for three generations, floated at the perimeter of the crowd.

He'd been sent one of 10,000 invitations the O'Connor camp shipped out for yesterday's shindig.

"I came to support Bob," Mr. Weinroth said. "Let's hope he can turn things around."

Turning around the aircraft carrier that is Pittsburgh government, and doing so quickly, was on other minds as well. Gillian Orsi, who described herself as "just a single mom who's out of work" was in the bleachers moments before Mr. O'Connor took his oath.

"I just lost my job and I'm kind of waiting to see what he has to say about making things better," Ms. Orsini said. Currently living in Beechview, but raised outside Philadelphia, she was thrilled, too, that Gov. Ed Rendell was about to appear.

"I grew up with his face on TV," she said.

All of this made it a bit odd when Gov. Rendell, a man known to regard the speed limit as an argument with many sides to it, was introduced and eyes turned to an empty chair with a sign that said, simply, "Gov. Edward Rendell."

"And, boy, will he be here soon," promised emcee, Larry Richert.

In a moment, Gov. Rendell appeared, perhaps tellingly, from inside the building -- the same hallway lined with food being made ready for the locusts -- gave a pep talk and, in a wink, Mr. O'Connor was mayor and the crowd surged toward tables groaning with food.

Mr. Weinroth, who had hoped to spend a bit more of inauguration day in the mayor's office, stood in line with the others to greet Mr. O'Connor, congratulate him, have his picture taken and be moved along by aides who wondered if their boss's newly implanted titanium knee could last the first day in office.

"It's a nice office," Mr. Weinroth ventured. "I may be here in future years." To his back, Mr. O'Connor was furiously shaking hands next to a pile of coats.