YELLOWSTONE NATIONAL PARK, Wyo. — Ticking away without fanfare, the clock did its work stationed on the stone fireplace in the Old Faithful Inn in Yellowstone for 80 or 100 years.

Traveling through the years, the clock's minute hand crept around the face more than 700,000 times.

It needed a little help along the way, repairs pieced together in the boondocks with versions of chewing gum and baling wire. Finally, as it wore down, there was a timely crisis.

"What was there was a real basket case," says Dave Berghold, a clock expert from Bozeman, Mont., who was called in to try to keep the Old Faithful clock ticking. "It had been patched and patched and patched."

Even so, to Berghold, the Old Faithful clock looked like a treasure.

A sweeping pendulum more than 13 feet long, hands about the size of yardsticks and stately Roman numerals testified to how the clock originated in the shop of a skilled Livingston blacksmith about 1903 or 1904, according to one history buff.

Berghold says he told the people in charge — officials in the park and at the concessionaire who manages Old Faithful Inn — "You should really have this thing done right." So he got the job of restoring the Old Faithful clock.

Starting in May, Berghold enlisted two fellow Montana collectors: Dick Dysart, a retired entomologist in Livingston, to do the historical research, and Mike Kovacich, a machinist in Anaconda, to reinvent the mechanics.

How bad was it? The Old Faithful clock had not been striking the hours, and the pendulum was no longer connected to the gears.

"We had to rebuild it from scratch," Berghold says.

Kovacich also did the math, working upward from the old pendulum: with a pendulum 156.5 inches long, each swing of it will last 2 seconds, which means a ticking-gear ratio 30-to-1, which means "a 72-tooth gear 6.5 inches in diameter, with 12-tooth pinions and an escapement 3.5 inches in diameter," and so on, he rattles off.

Kovacich also fashioned what he calls an "endless rewind system," modeled on one invented around the turn of the century, but using a small electric motor tripped by a mercury switch, to constantly rewind the pendulum and keep it moving the gears.

Berghold wanted the mechanism to slide on synthetic rubies, which reduces friction.

Dysart researched the original craftsman, George Colpitts, who not only hammered horseshoes around Livingston but also served as a town alderman, as Park County assessor and maybe as a deputy.

The blacksmith's touch shows elsewhere in the inn. He also made the fireplace andirons and the wrought-iron straps on the massive wood doors around the time the inn was built in the winter of 1903-04, Dysart says, though he adds, the exact history remains "a little murky."

Not much is known about the original clock, Dysart says.

"You're lucky to find a (historical) photo of an interior, even of the Old Faithful Inn," he adds.

Dysart's research convinced him that at least the clock's face, pendulum, counterweights and wrought-iron brackets are original.

The revived clock began ticking in mid-September.

"Anything to do with maintaining these historic buildings in their original condition is very helpful," says Cheryl Matthews, a park public information officer. "We're very pleased."