The tight hand

De strakke hand

Strolling around at your leisure, taking in all the beauty that the city has to offer and also learning something from it. That is of course right up our alley and it is what the artist collective De Strakke Hand van Utrecht manages to realize with the art series Wall formulas, in collaboration with physicists Sander Kempkes and Ingmar Swart. The series is a nice mix of physics, art and history that makes you even more aware of how great UUU actually is.

What do you know about the scientists who put Utrecht on the map in the field of physics? Since 2019, the artist collective De Strakke Hand has ensured that you can no longer ignore the facts. They decorate the walls of UUU with gigantic masterpieces and bring great names in physics back to the streets of Utrecht.

Do we remember the Doppler effect?

The first life-size painting was dedicated to the Doppler effect by Buys Ballot (1817-1890). A Utrecht professor and the founder of the KNMI, who in 1845 was the very first to demonstrate the Doppler effect experimentally. De Strakke Hand is always looking for suitable locations for their work, and if you've already walked the walking tour from the Utrecht East Tassie , we don't have to explain to you why this painting of the Doppler effect can be found next to the railway. Need a refresher? You can clearly hear the Doppler effect when an ambulance or racing car passes by: the sound of these vehicles suddenly sounds lower after they have passed. Doppler had already predicted this effect in 1842 (hence the name), but at that time there were no vehicles that drove fast enough to demonstrate it. When the brand new railway line between Utrecht and Maarssen was opened a few years later, Buys Ballot saw his chance: he borrowed a train, put brass instruments on an open carriage and had observers along the railway note the difference in pitch. You will find the artwork near the railway at the end of the Burgemeester Reigerstraat.



The Drunk Man's Walk

In 2020 it was the turn of Professor Leonard Ornstein's (1880-1941) De Random Movement. with the random movement he formulated to explain his random movements (joh!), of the

elasticity of rubber to the unpredictable walk of a drunk. That is why the random movement is also called the drunken man's walk. On the ten meter high wall you can see Ornstein behind his desk, next to it a drunk, stumbling man and a trambus from the thirties - an aspect that De Strakke Hand added to simulate the period in which the physicist worked, as well as the use of the typical thirties font. The formula of the drunken man's walk can of course also be found in the work. Ornstein was director of the Physics Laboratory which again explains the location of the artwork, as the lab is near where the painting can be found on the Oosterkade.


Like us, De Strakke Hand hopes to add more works to the Wall Formulas series. Fortunately, for now there are already many beautiful works of the collective to admire in the streets of Utrecht. Curious about more? In our Utrecht Tassie tours we teach you all about it.


Hit the road with a Tassie!