The Great Hall at the old Buhl Science Center stands empty except for the childhood memories of Pittsburghers who caught their first glimpse of Saturn's rings in the observatory and chuckled over what they would weigh on Mars.

Under the planetarium dome, where generations of the curious gazed at star shows, the old projector waits in the dark for a team of technicians that may dismantle it and take it to Dallas.

But an amateur astronomer who used to work at the old science center in Allegheny Center hopes to persuade the city to find a buyer who would allow the city to preserve and periodically run the old planetarium and observatory.

The city of Pittsburgh owns the marble-walled science center, but has had trouble finding someone to buy or lease the idiosyncratic building with its odd-shaped rooms.

Officials at The Carnegie Science Center, which replaced the Buhl, have arranged for a college in Dallas to pay for the expensive disassembly of the old planetarium projector and observatory telescope and rebuild them as working historic exhibits in a new planetarium under construction there. But first the city must transfer ownership of the equipment to the science center.

Pittsburgh has no place to exhibit the old equipment, they say. And if it does not go to Dallas, science center officials say, the antique astronomical equipment will be dismantled and left to die an ignominious death, gathering dust in storage.

Glenn Walsh of Mt. Lebanon is fighting to keep the equipment here.

When the Buhl Foundation built the planetarium in 1939 and gave it to the city, Walsh said, it was only the fifth planetarium built in the world.

"This is a very important historical preservation issue," Walsh said. ''Pittsburgh was a pioneer in the development of planetariums as a means of educating the public about astronomy. Until we're absolutely sure (the projector and telescope) cannot be used in the building, we should not send these historical artifacts away."

The 57-year-old Zeiss II projector, which looks like its has antique deep- sea diving hoods attached on each end, is one of the oldest major planetarium projectors in the world that still works, he said.

City Council will hold a hearing on the proposed transfer of the old projector and telescope to the college in Dallas at 2 p.m. tomorrow in council chambers.

Whether the city keeps the old projector and telescope is a question of whether the tug of heartstrings and history again gives way to what is practical. Will another piece of Pittsburgh's history go the way of Syria Mosque, Horne's, Gimbles, Gulf Oil and the steel mills?

White Italian marble gleams from the walls of the long Great Hall at the
entrance of the old science center. The patterned terrazzo floors were handmade by an old-time technique in which chips of stone were ground smooth.

"I've shown it to a number of groups," said Thomas Wilkinson, security and building manager for The Carnegie Science Center. "They all say the same thing: 'It's a great place, but we can't use it.' "

Although the city has been marketing the building for a few months, it has had trouble attracting a buyer or renter because the circular planetarium is encircled by odd-shaped, small rooms, he said.

Potential users also have been scared off by the fact that the building will have to be rewired, have fire sprinklers installed and be made accessible to the handicapped, said Deborah S. Miskovich, director of the city's Department of General Services. She does not have high hopes for finding a buyer who would be willing to allow the planetarium and observatory to be maintained.

The Carnegie Science Center originally put the telescope and projector in a package deal negotiated with the Navarro College Foundation in Dallas as a way to preserve them and keep them operating, said Paul Oles, assistant director for the planetarium-observatory at The Carnegie Science Center.

Money from the deal would be used by the science center to produce a planetarium program depicting a virtual reality trip into a living cell. The National Science Foundation already has given the science center and Carnegie Mellon University a $639,000 grant to produce the show, which would be distributed around the world.

But the science center needs another $550,000 to buy a computerized projector, Oles said. Navarro had agreed to buy the center's existing projector and some services, as well as the Buhl equipment.

To keep the deal from falling through, the science center recently renegotiated its deal with Navarro. They tentatively agreed to supply a Carnegie-produced planetarium show if the city decides to keep the old Buhl equipment.

The old projector has only historic value, not monetary value, Oles said. But he hopes the old telescope and projector will still be included in the deal.

"I would like to see (the Zeiss) in the Navarro proposal because it would be displayed and Pittsburgh would get full historic credit," Oles said.

LIB7