THE two enduring mysteries of America’s Watergate scandal were the identity of Deep Throat, the crucial source of the Woodward and Bernstein investigation, and the 18½-minute gap in a key White House tape recording.

Rose Mary Woods, President Nixon’s devoted personal secretary, became famous overnight for her inadequate explanations about the erasures in a vital tape she was transcribing of a conversation between Nixon and his all-powerful chief of staff, H. R. Haldeman. The conversation took place just three days after the notorious Watergate break-in of the Democratic headquarters, and the tape was widely believed to contain the first evidence of Nixon’s knowledge of the Watergate scandal and cover-up.

Rose Mary Woods had been working for Nixon for 23 years, since the days when he was in Congress, as an employee, confidante and close family friend, and was known for her fanatical loyalty to The Boss — as she always insisted on calling him.

She was known in Washington as the second-most important woman in Nixon’s life, after his tense and long-suffering wife Pat. At a dinner in her honour at the American Newspaper Women’s Club, Nixon sent a telegram to her addressed to “the most discreet woman in the world”.

In the early days of the Nixon Administration, Haldeman and John Erlichman, the chief domestic policy adviser, the two grim keepers of the White House “Berlin Wall”, did their best to reduce her role. But when they fell into disgrace and were eventually imprisoned, Woods came into her own and was promoted to executive assistant with three secretaries of her own.

Just as it began to appear, through lack of hard evidence, that Nixon might be able to survive Watergate, a White House official sensationally disclosed that all conversations between Nixon and his aides had been tape-recorded by the President. After a long legal battle in which Nixon claimed executive privilege, he was ordered to turn over the White House tapes. Woods was given the job of transcribing key tapes relating to Watergate, along with all the famous expletives which sounded more like conversations between Mafia hoods than the top members of the US executive.

When the gap was discovered, Woods was summoned before Judge John Sirica’s Watergate court for three days of questioning. She testified that she “must have” caused the gap adding: “All I can say is that I am just dreadfully sorry.”

Woods was then asked to demonstrate in court how she might have inadvertently made the gap while having a telephone conversation, and her contortions, before a disbelieving court, became known as “the Rose Mary Woods stretch”. She had to create receiving a telephone call while transcribing. It involved removing earphones, stretching with her left hand backward to the main desk telephone, lifting the receiver, then with her right hand pressing the tape record button instead of the stop button, while all the time keeping the pedal depressed with her left foot on its forward play side.

Her desk was 6ft long, and Woods was not tall. From the demonstration it was clear that she could not hold the phone and keep her foot on the pedal inadvertently, as she claimed, but would need to keep her leg fully stretched throughout a long phone conversation to perform the operation.

At one stage it looked as if she might have to join a long line of White House employees charged with obstructing justice. But she always insisted the gap was accidental, and although the prosecution said her account was implausible they were not able to disprove it.

Asked outside the court if she still regarded Nixon as an honest man she replied: “That is a rude, impertinent question — the answer is yes”.

Nixon was eventually driven from office by the discovery of another tape in which he was heard conspiring to cover up White House involvement in the Watergate break-in.

Rose Mary Woods, a slender young redhead when she first met Nixon, was brought up in Sebring, Ohio, by Roman Catholic parents. She once told a friend: “I would no more dream of changing my job than I would of getting a divorce if I were married. Both are against my principles.”

Her fiancé died when she was 17; her career seemed to be her life, and she developed a close relationship with Pat Nixon and the two daughters. After Nixon’s resignation she stayed on for some time working in the former President’s office in California.

But before leaving the White House she had one final task to perform when Nixon asked her to tell his family that he was going to resign. Nixon told her: “Tell them the whole bunch is deserting now and we have no way to lobby them or keep them,” he said.

She did as Nixon asked, and the occasion was recorded in the diary of Nixon’s daughter Tricia as “a day of tears”.

Rose Mary Woods, personal secretary to President Nixon, was born on December 26, 1917. She died on January 22, 2005, aged 87.