There’s a new nail in the coffin of the late, disgraced President Richard M. Nixon, who died in 1994. A new biography being published today, “The Arrogance of Power” by Irish journalist Anthony Summers (whose previous books include intimate portraits of Marilyn Monroe and FBI founder J. Edgar Hoover), asserts that Nixon took a mind-altering drug without a prescription and that he beat his wife, Pat. The drug Dilantin, was given to Nixon in 1968, the first year he took office, says the book, which reportedly cites Nixon aide John D. Ehrlichman as its source. (Ehrlichman, like Nixon, fell out of the White House in the wake of the 1974 Watergate scandal.) As for the claim of spousal abuse — Summers writes that, among other times, Nixon beat his wife black and blue after he lost the bitter 1962 California gubernatorial race — the author quotes several sources. But John Taylor, director of the Nixon Library, speaking about the book to The New York Times on behalf of the Nixon’s daughter, Julie Nixon Eisenhower, told The New York Times that the claim is “utterly inconceivable.”