How President Richard Nixon spent his last day in the White House

— -- On August 9, 1974, President Richard Nixon woke up with a start after a restless night.

“I looked at my watch,” Nixon said years later. “The battery had run out, worn out, at 4 o’clock the last day I was in office. By that day, I was worn out too.”

On this day, Nixon was to resign and hand over the presidency to Vice President Gerald Ford after the Watergate scandal left him facing impeachment.

Nixon talked about his final hours in the White House during an interview his former aide, Frank Gannon, conducted in 1983. The Nixon Presidential Library began releasing portions of the Gannon interviews in August 2014 leading up to the 40th anniversary of Nixon’s resignation.

Nixon recounted to Gannon that in those final hours of his presidency, he still had a monumental, essential responsibility.

Alexander Haig, who was then Nixon’s chief of staff and went on to become President Reagan’s Secretary of State, knocked on the president’s door.

“He brought one piece of paper. There was one line on it,” Nixon told Gannon. “He said, ‘You know, we forgot to do this. Would you sign it now?’ – ‘I hereby resign the office of president of the United States.’ I signed it. He took it out.”

Ron Ziegler, who was then Nixon’s press secretary, told ABC News in an October 1998 interview that he would never forget watching the president and First Lady Pat Nixon come down the elevator from the residence that morning. Nixon was giving a farewell address to his White House staff that was televised.

"He said, ‘I have to do this,’ and so he went… he felt this very deeply. He knew he had lost the respect of the American people," Ziegler said.

Nixon and the first lady entered the East Room to say goodbye to his cabinet and the White House staff. They were met with a long round of applause.

“The farewell speech to the staff, it was very difficult because he was really letting down his guard for one of the few times in public,” as his daughter Julie Eisenhower told Barbara Walters in 1986. “His voice cracking with emotion as he spoke about his parents and speaking about a man is not defeated until he gives up.”

During his farewell speech, Nixon talked about his mother, “a saint”, he said, and sharing an inner pain. “Only when you have been in the deepest valley can you ever know how magnificent it is to be on the highest mountain,” he said.

Nixon later told Gannon that he was speaking from the heart in that moment. He said his other daughter Tricia later wrote in her diary “that for the first time, she was glad people were able to see Daddy as he really was.”

After his farewell speech, Nixon’s aide, Stephen Bull, said the president then went down to the Diplomatic Reception room to meet with then Vice President Gerald Ford.

“I think he said, ‘Mr. President, I’m sure you’ll do a fine job, God bless you,’” Bull said Nixon told Ford. “And then went out and boarded the helicopter.”

Nixon told Gannon in the 1983 interview that his wife had boarded the helicopter first and then he followed.

“[I] turned around, and there were all the crowd out there on the lawn,” Nixon said to Gannon. “I kind of raised my hand. I didn’t know whether it was a salute or a wave, but that was it. Turned, went in and sat down in the plane, heard the engines whirl up. I closed my eyes.”

“And as the helicopter began to rise,” the president continued. “I heard Mrs. Nixon, who was sitting in the seat next to us, speaking to no one in particular but to everyone, and she said, ‘It’s so sad. It’s so sad.’”