The wetting trap chair: Denmark’s oldest whoopee cushion

One of the more amusing items in our large collection is the ‘wetting trap chair’, which is probably the oldest whoopee cushion in Denmark. At first glance, it looks just like a regular chair, but do not be fooled by its innocent appearance: the wetting trap chair is equipped with a hidden mechanical contraption that not only traps the person who sits in it but also wets their trousers! To make matters worse, a built-in bellows makes a sound as if the trapped person let out a loud fart.

We do not know exactly when the chair was made, but we believe it dates from the late 17th century and was used at the court of Christian V.

The prank chair is one of the few preserved devices of its kind in Europe, and it is the only known chair to combine a trapping mechanism with a water mechanism and a whoopee cushion. Until recently, little was known about the chair’s history, including whether it was ever actually put to use. Now, two PhD students, Louise and Casper at the University of Copenhagen, have filled, this gap with their brand-new, award-winning research.

‘We encountered the chair while working as tour guides at Rosenborg Castle and were surprised to find that so little was known about the chair’s original use. So we chose to take a closer look to see what untold stories it might hold,’ says Casper, describing the inspiration for their research project.

Thanks to Louise and Casper’s research, we now know that the chair was in fact used as a whoopee cushion. At more than 350 years old, it seems safe to label it Denmark’s oldest such device.

‘We discovered a wonderful source from 1775 that describes it as “an armchair that squeaks when you sit down to give the impression that you passed gas”. This tells us that the chair’s sound mechanism was indeed perceived as a sort of whoopee cushion at the time,’ says Louise.

Fun and games at the royal court

Generally, there were strict rules for proper behaviour at court during the absolute reign of Christian V, but the common rules and hierarchies were temporarily eased slightly on special occasions. At the Shrovetide carnival, for example, people could dress up and pretend to be someone else. And in connection with a royal hunt, Christian V might choose to punish hunters with embarrassing pranks to the amusement of the rest of the hunting party. The wetting trap chair will have fit perfectly into these types of special-occasion pranks.

Award-winning research

Casper Thorhauge Briggs-Mønsted and Louise Kjærgaard Depner’s research recently received the annual essay award from the Society for Court Studies. Their essay on the wetting trap chair and the other mechanical prank chairs around Europe will be published in the international journal The Court Historian in spring 2025.

See the wetting trap chair

Here at Rosenborg Castle, you can see the wetting trap for yourself and hear much more about how it was used.