Serie XIII; Ten string models of ruled surfaces of order four

Number Title Date of Design Dimension (cm) Material
Serie XIII, nr. 1 Ruled surface with two real double lines and four Pinchpoints on each of them. 1886 18-18-18 String
Serie XIII, nr. 2 Ruled surface with two real double lines and without Pinchpoints. 1886 18-18-18 String
Serie XIII, nr. 3 Ruled surface with two real double lines and four Pinchpoints on both lines. 1886 18-18-18 String
Serie XIII, nr. 4 Ruled surface with two conjugated imaginary double lines. 1886 18-18-18 String
Serie XIII, nr. 5 Ruled surface with self intersection forming a line and with four Pinchpoints on the line. 1886 18-18-18 String
Serie XIII, nr. 7 Ruled surface with a triple line and two constant tangential planes along the line. 1886 18-18-18 String
Serie XIII, nr. 10 Ruled surface with one real double curve of third order and without Pinchpoints. 1886 18-18-18 String