The arms push and pull a plate across the top of a cylinder wrapped with cloth covered wire. Im guessing this somehow makes electric current but I didnt connect anything to the contacts. The unit is quite heavy, about 12 lbs, and measures about 8 ½ long (from outer diameter of the wheel to the base opposite) by 6 ½ tall by 6 ¾ wide. The wheel diameter is 6.
There is a sign included which was found with the motor. One side is nicely hand written with the text, written in French language, "Moteur execute parles elevs du cours technique de l'ecole St Joseph, Place, Daumesnil" which translates to Engine made by the students of the technical course of the school St Joseph place, Daumesnil, Morlaix. Written in graphite, lower left, is #161. A guess is that this could have been an exhibit at a science or technology fair, that and the way that the card is decorated and that there is a hole at the top where the card was hung for display. The other side is a photo postcard with an image of the St Joseph school.
There is ink writing on this side. The item "Vintage RARE Steam Engine Model Reciprocating Solenoid Motor France St Joseph" is in sale since Friday, February 26, 2021. This item is in the category "Antiques\Science & Medicine (Pre-1930)\Scientific Instruments\Other Antique Science Equip".The seller is "greenportny" and is located in Greenport, New York. This item can be shipped worldwide.