Desargues' theorem in space and in the plane
Desargues' theorem in space and in the plane. Two planes (wood), each with a triangle (black); the side extensions (green) intersect pairwise on the line of intersection of the two planes, this is the Desargue line. The connection lines of the vertices (red fibers, tightened by weights) go through a point at each position of the plane.
See also model 431.
Showcase of this model is Case number 27
Fischer, G.(1998). Analytische Geometrie, vieweg studium, Braunschweig/Wiesbaden, p. 159f..