At a recent gathering of watchmakers we encouraged all to bring a tool they just weren’t sure about. This one managed to stump all of us. The box is labeled “Jeu Arbres Lisses 1re qualite” which as best I can tell means a set of straight shafts or arbors of first quality, But my French is quite rusty (it has been more than 10 years since I studied or spoke any.) There are 24 little “bobbins” inside each with a different size pulley affixed to the shaft. The shafts are of varying lengths and diameters and seem to have a slight taper. If you know what they are and/or what they are for leave a comment, or even if you don’t take a guess.
This set whose pictures I clearly borrowed shamelessly from an ebay auction are not of the exact set brought to our meeting and add an additional clue (in French). They seem to add that they are “rectifies a la meule,” which I guess means they were made with a grinding stone or are perhaps used for grinding? If you know let me know.