CJAMY. Camille Goubert’s column is broadcast daily in the program “See Jamie”, which is presented on France 5 on Mondays to Fridays at 5 pm.

Around Mont Saint-Michel lies an insidious and humid region, made up of mud, sand and water: quicksand.

Quicksand is a non-Newtonian fluid

If these sands are dangerous, it is because they are so-called “non-Newtonian” fluids, that is to say, they change the continuum whether they are killed, stirred, or left them alone. For example, yogurt is non-Newtonian: when you shake it, it becomes liquid. Water, by contrast, is a Newtonian liquid: no matter if you tap on it, it will not be more or less thick, it will remain liquid. Conversely, a mixture of water and cornstarch is non-Newtonian, it is liquid if it is handled gently, but it becomes harder if someone or someone hits it. Some have even filled the entire swimming pool, and it is possible to run, jump, or roll over it without risk … but if they stop or fall, they sink!

Mud bursts on stirring in it

Around Mont Saint-Michel, sand is mixed with water and, above all, with soil. It is the latter that changes its behavior according to your movements. The more we stir, the more the soil structure breaks down: quicksand therefore becomes more liquid, and we drown. And so does the sand: it sinks to the bottom and covers your feet, while the water rises to the surface. This is how the feet of the walkers can get tangled up in this clever wet prison. The mixture around the feet can be so thick that enough force would be needed to lift a small car to get out of it!

How to get out of quicksand

There is no need to call Indiana Jones, to get out of quicksand, it is better to rely on physics professor and researcher Daniel Bonn. according to him, “When Indiana Jones is seen using his lasso and hanging on his horse to get out, he should have been cut in half.“In fact, you have to do a circular movement with the legs to allow the bottom to pierce the hole with water and free your leg at the end. In fact, the human body is not enough to be swallowed by them. Quick. .: We end up swimming. But if we’re stuck during the rising of the tide, we can still drown. Conclusion: In Mont Saint-Michel, take a trip, eat buttermilk pancakes, take a walk … But this place. Not. When you sit. To make pies.