Workers started demolition in the morning at the rear of the buildings, which once housed the headquarters of the Philadelphia Life Insurance Co. A large crane with a wrecking ball is breaking down the masonry walls; the structures, between Arch and Cherry Streets, should be leveled by tomorrow, said Edward Myslewicz, a spokesman for Pennsylvania's construction agency, the Department of General Services.

Late last year, DGS announced it would not honor a 2004 preservation agreement signed by the Convention Center Authority and the state Historical and Museum Commission. That action prompted strong protests from the Preservation Alliance, the Design Advocacy Group, the National Trust for Historic Preservation, and others complaining it would make future compromises impossible.

DGS had argued that the buildings were structurally unsound, and that fixing them would add to the $700 million expense of the Convention Center expansion.

The ease with which DGS could write off the buildings "exposes the weaknesses of Pennsylvania's history code," said John Gallery, who runs the Preservation Alliance. "Other state historical commissions, like New Jersey's, have much stronger powers."

His group is beginning an effort to amend state law.

John Wesley, a former director of the state historical commission, said Judge Keith B. Quigley's ruling in the case was a major setback for preservation in Pennsylvania and "incredibly destructive and questionable."

The 2004 agreement with the Convention Center Authority was initially viewed as a model for future compromises. Philadelphia preservationists agreed to sacrifice other historic buildings in the expansion zone, and the center's authority promised it would weave the Broad Street buildings into its new two-block-long glass facade, which is the signature element in its expansion.

Despite calls from preservationists to respect the 2004 agreement, DGS began tearing off the facades of the two structures the Saturday before Christmas. The work was halted two days later so the court could determine whether the preservation agreement amounted to a legal contract. Quigley ruled that it was not.

"The decision in the case," Wesley said, ". . . may stand as a landmark for the demise of historic preservation in Pennsylvania." Noting that all the decision-makers were state agencies, he argued that "the final decision" to stop the demolitions rested "at the hands of our governor."

The linked buildings were the insurance company's original neoclassical headquarters from 1915 and a 1962 addition by renowned Philadelphia architect Romaldo Giurgola. The pair was admired internationally because Giurgola's addition demonstrated how modernist design could adapt to a traditional urban street grid.

The Giurgola design remains a staple in architecture-school curriculums.

For video of yesterday's demolition, plus previous video and photo coverage of the project, go to http://go.philly.com/

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