The Beatles were at the height of their immense popularity when the tape was recorded at Scottish Television studios on April 30, 1964. The band had recently toured America, winning huge audiences on the Ed Sullivan show and shooting to the top of the charts on both sides of the Atlantic.

The interview was only broadcast in Scotland and sat in a film canister until it was discovered by film historian Richard Jeffs, who was astonished to find the familiar Liverpudlian accents of the Beatles on the tape. It was not immediately clear who owned the garage or why the film was there.

The audio portion of the tape was found to be still usable for radio broadcast, allowing the British Broadcasting Corp. to showcase its interview 44 years after it was recorded.

On the nine-minute tape, Lennon describes the fateful day in rock-and-roll history when he first encountered McCartney. Both were unknown teenagers at the time.

"I was playing at a garden fete in the ... village where I lived just outside Liverpool, playing with a group, and he came along and we met," said Lennon, who was a member of a soon-to-be-forgotten skiffle band at the time.

McCartney said they were introduced by a mutual friend called Ivan.

Lennon and McCartney became fast friends - once they found out they had skills in common, and a shared taste for American stars like Fats Domino and Little Richard - and they soon joined up with teenage guitarist George Harrison to form the nucleus of what would become the Beatles.

Drummer Ringo Starr would come much later, just before the group started its string of unforgettable No. 1 hits.

On the tape, Lennon and McCartney - hailed by many as the finest British songwriters of the 20th century - discussed the haphazard way they composed together during the Beatles' early days, when they were under intense pressure to generate hits while keeping up a bone-crushing touring schedule.

McCartney said that the two usually worked on songs together but that sometimes Lennon wrote songs completely on his own.

"Normally we sit down and try and bash one out," said McCartney. "But then again, there's no formula, because he (Lennon) can come up with one day completely finished. We still say we both wrote it, though."

The two principal songwriters, who would later have a falling-out as the band was breaking up, sounded extremely relaxed and affectionate with each other.

McCartney said they used whatever instrument was available when composing.

"Well, you know, it depends," he said. "Sometimes we write them on old pianos, anything that's lying around."

McCartney, who would later pen classics such as "Eleanor Rigby" and "Let It Be," told the interviewers that he and Lennon started off writing comical songs, including his first effort, the largely forgotten, "I Lost My Little Girl."

While the Beatles eventually wearied of the pressures of live performances, when they couldn't hear their own songs because of the noise from the fans, McCartney said in 1964 that they adored the attention they received from their screaming, fainting female fans.

"We love that," he said. "The atmosphere in the theaters. It's marvelous."

The BBC posted a notice on its website indicating that the precious tape, and a number of others found at the same time, are now being kept in a temperature-controlled warehouse to protect them from the ravages of time.