Set of 7 unassembled cardboard geometrical models in 4 separate packets, showing surfaces of the second order: (1) Ellipsoids having 22 sections, (2) Ellipsoids having 30 sections, (3) Hyperboloids of 2 sheets, (4) Hyperboloids of 1 sheet, (5) Paraboloids, (6) Hyperbolic Paraboloids, (7) Cones [NB stands marked 1876-842 hold paper models 1901-88 ] Set of 7 unassembled cardboard geometrical models in 4 separate packets 1876