LONDON — Five large envelopes containing a 1,105-page memoir in the Gothic handwriting of Adolf Eichmann may now hold the key to a dramatic libel trial in London.

The memoir, written while the chief engineer of the Holocaust was in an Israeli jail awaiting execution in 1962, has been locked away in Israel's National Archive for nearly four decades.

Now this document — released to the public Tuesday — has been given new life and, unwittingly, new purpose in the hands of lawyers in London who are defending Holocaust scholar Deborah Lipstadt.

The U.S. professor and author is being sued by Holocaust revisionist David Irving, who claims he was libeled in her 1994 book "Denying the Holocaust: The Growing Assault on Truth and Memory," published in Britain by Penguin Books.

Irving, who denies that Auschwitz was a death camp and insists that the number of Jewish victims has been grossly inflated, maintains Lipstadt ruined his career by accusing him of distorting historical facts.

Under British libel law, the onus of proof is on Lipstadt to show that her contentions are accurate: She has to prove that Irving possessed information about the Holocaust that he deliberately distorted, selected or suppressed to suit his purposes.

Irving is making full use of this advantage in the courtroom by simply claiming that he is not an expert in the Holocaust, a subject that he told the judge he found boring. By asserting his relative ignorance of the subject, Irving increases the burden of proof on Lipstadt and her defense team.

But the Eichmann memoir — which is said to contain a meticulous record of the ghettoes and the cattle trains that took millions of Jews to the death camps of Eastern Europe — might change all that.

Among the fragments penned by Eichmann during the summer of 1961, while he was awaiting the verdict in his trial:

*"I said [in court] that what happened with the Jews, which the government of the German Reich brought about during the last Great War, was the most enormous crime in the history of mankind."

*"I witnessed the gruesome workings of the machinery of death; gear meshed with gear, like clockwork."

*"It was the biggest and most enormous dance of death of all times."

While the memoir had been kept under lock and key in Jerusalem for nearly 40 years, it has been available to a handful of scholars. And Irving, crucially, is among the few who assert that they have acquired a detailed knowledge of the memoir.

In the past, Irving claimed to have received two packages containing 426 pages of the document from a member of Eichmann's family while he was in Buenos Aires during a lecture tour of Argentina in 1991.

He has used parts of the Eichmann account, presumably confident that they would never be made public, to support his contention that there was no systematic genocide and that Hitler neither gave orders nor had knowledge of any mass killings of Jews.

In a 1997 letter to Robert Jan van Pelt, a Holocaust historian who testified for Lipstadt earlier in the trial, Irving also cited the Eichmann memoir to cast doubt on the existence of gas chambers. He claimed that while Eichmann described an "experimental" truck gassing, he was never shown a gas chamber at Auschwitz.

Irving's presumption that the Eichmann memoir would remain securely locked away might prove to be the fatal flaw in his case.

"There was no denial of the Holocaust there," said Gavriel Bach, a junior prosecution counsel at the Eichmann trial in 1961 who went on to become an Israeli Supreme Court justice and was the first person to read the memoir.

"Eichmann tried to show that he was a minor cog in the machine and he had to obey orders, but he describes how terrible it was," Bach said. "He wanted his family to see it, and to see his role. Maybe he wanted to convince his family he did not take a central part in the Final Solution."

Now retired, Bach was Eichmann's main contact with the outside world while he was in jail.

At one point, after witnessing the liquidation of a group of Jews, Eichmann's memoir, perhaps self-servingly, records his shock and his consumption of large quantities of alcohol as a tranquilizer to relieve his tension.

"In court," recalled Bach, "he admitted it was the most terrible crime in history. He says how he almost fainted when he saw the geysers of blood coming out of the bodies in the ditches."

Bach served on the panel of Israeli scholars and lawyers who decided Sunday night that the memoir should be given immediately to aid Lipstadt's defense. A spokesman for Israel's Justice Ministry said the panel agreed to give Lipstadt's lawyers a copy of the memoir as soon as possible "so she can defend herself in a lawsuit brought by a Holocaust denier."

Elyakim Rubinstein, Israel's attorney general, said Monday the decision reflected Israel's "historic sense of responsibility" to do "everything possible to fight Holocaust denial."

Last August, the Justice Ministry announced that the government intended to see to it that the memoir was published in full by German scholars along with "commentary and appropriate accompanying material." A lawyer representing one of Eichmann's two sons officially asked the government for a copy of the manuscript at that time.

Rubinstein said the request to use the memoir in the Holocaust-denial suit expedited the process of releasing both the handwritten manuscript, as well as a typed copy.

As a result, the final labors of the Final Solution's chief logician may serve to put to rest the contention that the Holocaust never happened.