Jokes at the expense of the military are a staple of British humour. Marine humour, especially humour at an official military function, sounds like a contradiction in terms. An elaborate gag in the performance of The Bands of HM Royal Marines at the Mountbatten Festival of Music 2019, Royal Albert Hall, shows that serving marines can be very funny.
The setup is simple. A well-turned out marine is playing The Blue Danube on a marimba when he is interrupted by the sound of water dripping. It can't be from the Danube; there must be a leak in the Royal Albert Hall. Time to call a plumber! A bumbling contractor sets up a wet-floor sign, tosses fittings around, and indulges in a bit of innuendo.
The Heath-Robinson-like device uncovered by the plumber is a thongophone (also called a tubulum or PVC pipe drum). An instrument from Papua New Guinea, it is played by forcing air through pipes of different lengths (pitches) by hitting the openings with rubber paddles (thongs). Traditional thongophones have a set pitch for each tube, but inventors like Blue Man Group have made variable pitch thongophones, such as that in the video. To further vary the sound, the pipes can be hit with drumsticks.
Despite the tomfoolery, the duet by the "plumber" and the marimba player is the third movement of Mozart's Piano Sonata No.11, The Turkish March. The final piece, where they swap instruments, dispels any doubts about the musical chops of the comic plumber. Appropriately for a military band, the music is the William Tell Overture, which often marks the arrival of the calvary in Westerns. To further demonstrate the use of PVC pipes as an instrument, here is thongophone innovators Blue Man Group:
The video of The Bands of HM Royal Marines demonstrates that, in the right circumstances, with sufficient rehearsal, Royal Marines are capable of slapstick with impeccable comic timing. It also shows just how skilled the Marine bands are. To date, the video has nearly 5m views on YouTube, so clearly both the humour and musicianship are appreciated.
"Thongophone" was the Oxford University Press Word of the Month for April 2017, and it is the term used by Wikipedia. Nonetheless, if you are interested in building your own thongophone (a number of tutorials of varying complexity are available online) it is useful to enter "PVC pipe drum" as your search terms.