"Kohl - Inclined Plane, C. 1900"
Large wooden inclined plane which is used on the one hand to demonstrate the laws of falling bodies and on the other hand to determine the coefficient of friction between two surfaces. The trolley and the scale are later but the plane is in perfect original condition with its three wooden feet. 60x40cm. 
Le Magazine de PROANTIC
TRÉSORS Magazine
Rivista Artiquariato