Emerick and the "Underwater Vocals" on "Yellow Submarine"

According to Geoff Emerick, there was much dope-smoking during the
recording of "Yellow Submarine."  To simulate the sound of a submarine
submerging, Lennon blew bubbles into a glass with a straw, which were
duly recorded by Emerick.  Lennon wanted to take things further; he
wanted a tank of water brought into the studio so that he could add
vocals while underwater.
George Martin attempted to dissuade John from this.  Emerick intervened
with the proposal that Lennon might sing into a *microphone* that had
been submerged in water.  Martin again disapproved, and warned Emerick
that is a mic was ruined by such a process, he (Emerick) would have to
pay for it.  This warning had a "sobering" effect on Emerick, but he
believed it was too late to back out.
A milk bottle filled with water was fetched.  The next problem was
waterproofing the mic.  John called out to Mal Evans, asking him what he
had that would help.  Evans, Emerick recalled, "carried around a
doctor's bag inside which he'd stashed all kinds of things -- picks,
guitar strings, flashlights, crisps, biscuits, even household items like
tissues."  And on this occasion, Mal did not disappoint.  He reached for
his bag, felt around, and produced a condom.
[End of summary.]
I love this anecdote, which illustrates the way the Beatles' entourage
would think on their feet to indulge Lennon's far-out whims.  I'm
pleasantly surprised that they had Evans provide condoms -- presumably
usually for their regular purpose.