PITTSBURGH (AP) _ A snowman in sunglasses and a straw hat was a prominent guest but didn't stick around long for a celebration of the official beginning of summer.

Children lugged bags of snowballs and the snowman to the Buhl Science Center for Solstice Day, designed to teach children about the sun, including the fact that on June 21 each year it reaches its farthest point north of the equator.

More than 1,200 snowballs were brought to in response to an invitation last January to ''save those snowballs'' for free admission to the event, said Jo Lee, the center's spokeswoman.

''The 'Snowball Arena' was set up to entice kids into the science center and show them that learning is fun,'' said Ms. Lee.

Events included ''the great meltoff, the slowest race Pittsburgh ever had'' - a contest to find the slowest-melting snowball on the sunny, 76-degree day.

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SEATTLE (AP) - A campaign by a diehard who insisted that Coca-Cola bring back its old formula went flat when he couldn't pick out his favorite in a taste test.

Gay Mullins, 57, was given six, then three, then two colas in a test conducted by The Seattle Times, which reported the results Friday.

Each time he failed to distinguish the old Coke from the new Coke and colas by Pepsi, Royal Crown, Cragmont and Shasta. In a two-cola showdown between old and new Coke, Mullins still got it wrong.

Mullins, who had denounced the new Coca-Cola formula introduced April 23 as sweeter, flatter, and lacking in ''that old zing,'' says he has sunk $45,000 into his campaign to bring back the old Coke.

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BRIGANTINE, N.J. (AP) - A mechanic found out he needed more than a monkey wrench for a repair job when he opened the hood of a car to find a 4-foot-long snake resting on top of the air conditioner.

The snake slithered down into the engine, and mechanics, the local animal control officer and police spent about 11/2 hours removing the fender to catch the creature.

''I thought it was one of those rubber snakes until it started crawling around,'' said the mechanic, Carl Mutschler. He laughed at first, thinking it was a prank, but then the brown-spotted snake reared its head and hissed.

Robert Schoelkopf of the Marine Mammal Stranding Center said the snake would be sent to a zoo unless someone with a permit claimed it.

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WASHINGTON (AP) - It may be a 400-pound pile of rocks, but it still makes a great present - at least that's what scientists say about a set of 380 million year old fossils donated by the state of New York to the Smithsonian Institution.

Sen. Alfonse D'Amato, R-N.Y., on Friday presented the fossils, believed to be of some of the earliest land animals, to Dr. Richard Fiske, director of the Smithsonian's National Museum of Natural History.

The well-preserved remains of a mite, some spiderlike creatures and centipedes were discovered in a piece of mudstone taken from the site of a state power project about 40 miles southwest of Albany, N.Y.

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NIAGARA FALLS, Ontario (AP) - It was just another way to see the famous falls, but authorities were not amused by what they called a ''very, very risky'' stunt by two men who skydived off a 520-foot observation tower nearby.

The two landed in a parking lot, gathered up their parachutes, and sped away in a van, said Staff Sgt. Howard Chesney of the Niagara Regional Police.

''We were surprised,'' said Ray Thompson, general manager of the tower near Horseshoe Falls. ''What disturbs us is that if they had asked permission to make the jump, we might have given them the opportunity to do it under controlled circumstances.''

''It was very dangerous and very, very risky for themselves and for others,'' he said of the Thursday incident.

A mischief charge could have been filed against the two had they been caught, police said.