George Thomas, an architectural historian, agreed that the changes were "in this century unprecedented" and likened the dismantling to the Taliban's destruction of ancient statues of Buddha in Afghanistan several months ago.
Yesterday, the Rev. Paul S. Harris, head of program development at the church, said that the changes were necessitated in part by conversion of the building to cathedral status. Others, he said, were a result of a "reordering of the space" to make it consistent with a liturgical space more responsive "to the needs of the 21st century."
The Episcopal Bishop of Pennsylvania, the Rev. Charles E. Bennison Jr., could not be reached for comment yesterday. The Rev. Richard Giles, dean of the church, which was designated the Episcopal cathedral for Philadelphia about 10 years ago, this week declined to answer questions regarding renovations to the interior.
The church, at 38th and Chestnut Streets, was designed in 1889 by Philadelphian Charles Burns, an important ecclesiastical architect, and was remodeled after a severe fire in 1902.
The latest changes include the dismantling of the central marble altar and removal of memorial reliefs created by R. Tait Mackenzie, an internationally known sculptor who taught at the University of Pennsylvania. Mr. Harris said the reliefs, commissioned in honor of Howard C. McCall, who died in World War I, would be placed elsewhere in the cathedral.
The marble from the altar will be given away to "special people," he said.
The ornately carved pulpit, a memorial to the Rev. William Wilberforce Farr, a former rector, has been sold, Mr. Harris said. The onyx baptismal font, a gift from Anthony J. Drexel in memory of his dead children, has been dismantled, and parts of it will be incorporated in a new pool that will be installed in the cathedral.
Mr. Harris said the renowned murals in the apse of the church, created by Edwin Blashfield, artist of the Library of Congress murals in Washington and widely considered the one of the greatest of American muralists, would be preserved.
It is unknown at this time, however, whether Blashfield murals on the lower wall beyond the former location of the altar will be preserved. It is also unknown whether the extensive decorative painting and stenciling throughout the interior will be preserved. Last year, The Inquirer reported that parishioners and preservationists had expressed concern about the fate of the historic interior of the church, which had abruptly closed. The British-born Mr. Giles, named dean in 1999, said at the time that the floor needed greater support to accommodate the flexible seating associated with the church's cathedral status. The church pews had then been removed and the ornate choir stalls ripped out and sold, leaving the large, carved organ pipes jutting out over empty space.
It is unknown if the pipes, whose carvings matched other interior elements, have been removed.
Last year, Dean Giles said the church's stained glass - created by Louis Tiffany and John Hardman - would not be removed.
The windows are considered part of the church's exterior and are therefore under the jurisdiction of the Philadelphia Historical Commission. Any effort to remove the windows would be subject to city review.
The interior of the church, though cited as an important element in the listing by the National Register of Historic Places, is outside the jurisdiction of the Historical Commission, state courts have ruled.
Randall Cotton, head of the Preservation Alliance for Greater Philadelphia, said yesterday that the city featured many examples of historically sensitive church renovation - even renovation necessitated by changing liturgical needs. Cotton and others said they were distressed by the lack of information coming from the diocese. Meg Cave, a spokeswoman for the diocese, said a meeting would be scheduled for preservationists and church officials to exchange views.
Cotton noted that the renovation had already happened.
"It's very disconcerting to learn of this unnecessary dismantling," Cotton said.
Dean Giles, an outspoken advocate of liturgical and architectural reform who has written about his "flights of fancy" involving "gutting" old church buildings in order to renew them, said no other changes had been proposed at that time.
The church was closed in July 2000 because of what was described as the unsafe floor. That closure sparked considerable alarm and suspicion. A few months ago, the church was completely closed down and chain-link fencing was installed around it.
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