Harvard may be on the verge of losing one of its top historians, should his wife accept a tenure offer from Columbia University, administrators said earlier this week.

Virginia E. Papaioannou, associate professor of pathology at Tufts Medical School and wife of Mellon Professor of the Social Sciences Simon M. Schama, would not confirm the offer yesterday. But a senior Harvard official said the University has known of the offer from Columbia's College of Physicians and Surgeons since early summer.

Schama did not return phone calls yesterday and Monday. He told the New York Observer this week that it was a "possibility" that he would go to Columbia's history department:

"I can't really say anything because we're still talking, both of us, to Columbia. I'm prepared to say that."

Dean of the Faculty Jeremy R. Knowles said Monday that for the couple to leave Boston would be "an awful loss to history and biochemistry in this area."

"I understand that Professor Papaioannou has a splendid opportunity at Columbia, yet of course I hope very much that they will both choose to remain here," Knowles said.

A senior official said that given the financial climate, it would be hard find a competitive offer for Papaioannou in theBoston area.

The Observer reported that Papaioannou hasapparently been offered her own laboratory atColumbia.

Schama, a leading European historian, is theauthor of several books, including the bestsellingCitizens, an account of the FrenchRevolution, and The Embarrassment ofRiches, an examination of Golden Age Dutchculture and art.

Schama is known for his narrative approach toteaching and writing history