Demonstration of DESCARTES' Law of Angular Closure Deficit 4 of 6 equilateral coplanar triangles fold to One halve of an Octahedron The Angular Deficit is (1+4/2)*2*60°=360° - rotate by dragging the mouse - -------------------- (For a detailed discussion visit this site's page: Descartes' Law of Angular Closure Deficit) -------------------- --------------------