Perhaps the most famous erasure in history is 18 and one-half-minute stretch of buzzes and clicks in the surreptitious recording of a June 20, 1972 conversation between President Richard Nixon and White House chief of staff H.R. “Bob” Haldeman, which occurred three days after Nixon’s political dirty-tricks team committed the now-infamous Watergate burglary. Nixon’s secretary, Rose Mary Woods, later testified in court that she must have pushed the wrong button on her transcription deck and accidentally recorded over at least part of the gap

And we eventually find out that what was erased was an 18 minute long session of them singing “I Am Henry the Eighth, I Am!”, which was erased for the good of the general public’s sanity. . .

I thought it was Alices Restaurant.  At least he says so in the song.