The Independence Seaport Museum announced Thursday that it had received four gifts totaling $13.9 million, more than doubling its endowment and marking one of the largest gift totals ever made to the Penn's Landing institution, founded in 1960.

John Brady, head of the museum for four years, called the contributions "an endorsement" of the museum's direction, which he characterized as akin to "a transformation."

The gifts announced were $4.5 million from newly elected board chair Peter McCausland; $4.4 million from longtime museum supporter Peter R. Kellogg; $3 million from H.F. "Gerry" Lenfest, owner of Philadelphia Media Network and publisher of The Inquirer; and $2 million from an anonymous contributor.

The endowment now totals around $23.5 million. In a statement, McCausland said the museum's board "recognized that to be a top-tier institution, we needed to do more to establish long-term financial stability."

Brady said in an interview that the museum's strengthened emphasis on history and its developing focus on the sciences, including biology and environmental science, were ultimately responsible for heightened philanthropic interest.

"This is an endorsement of those plans [for the museum's direction] and a positive signal the philanthropic community is backing that plan," he said.

The museum, with a $3.6 million operating budget, has been running deficits ranging above $1 million. But Brady said progress has been made on narrowing and finally eliminating the gap; the expectation is that that will happen by the end of 2015.

The sharpened programming focus is designed to do that. For one thing, the museum wants to tap into the regional history audience, currently centered on Independence National Historical Park.

"We think we can do that and that we can do it by telling the story of the founding of the U.S. Navy right here," he said.

The museum is constructing, as an ongoing exhibition, a life-size replica of a colonial-era ship, the Diligence, Brady noted.

Perhaps most important, he said, is that the gifts will demonstrate the museum's vitality to other philanthropists. "It makes the institution's long-term viability much better," he said.

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