Leave it to the French to come up not only with a cooler sounding name than seismograph -but also to make them out of wood. Here are two examples of the idea. Now imagine that you combine them and end up with something 24 to 36 inches (60 to 90 centimeters) tall. The slightest movement will cause it to tremble - hence the name trembleur.
That's a U.S. dime at the base of the left one, two U.S. nickels at the base of the one on the right. The narrow sections of the one on the left are 1/8" (3 mm) in diameter.
If you want to test your fine motor skills - and how well you can sharpen your turning tools - to say nothing of testing your nerve - turn one of these. The French usually use a "bedan" but you can use a skew - with a bit of practice. It's a LOT easier if you have on end in a chuck, a live center on the other end, and a "string support" you can move in between. DO NOT snug up the tail center - any compression will raise all kinds of hell as you thin things down.
If you're bored with turning knobs, spindles and hair sticks - try one of these. They're fun!
Here's a site with instructions.
Try it. You might like it!