In the now infamous story, Producer George Martin didn't know what to make of it and, thinking John was sick, took him up to the roof of Abbey Road Studios to get some fresh air, not at all realizing for a moment the danger he was actually placing The Beatles' leader in (who just as easily could have believed he could fly down in his severely altered state.)
When George returned to the studio to continue the session and informed Paul McCartney and George Harrison where John had been taken, they rushed up to the rooftop to carefully bring him back inside. (The roof had no railings and was a 30foot drop to the ground below!) So as not to completely waste the evening, The Beatles worked on the piano track for "Lovely Rita" that night instead.
