Principal forms of the isometric system: deltohedron

Deltohedron

Principal forms of the isometric system: deltohedron

Principal forms of the hexagonal system: dihexagonal prism

Dihexagonal Prism

Principal forms of the hexagonal system: dihexagonal prism

Principal forms of the hexagonal system: dihexagonal pyramid.

Dihexagonal Pyramid

Principal forms of the hexagonal system: dihexagonal pyramid.

Principal forms of the hexagonal system: ditrigonal prism

Ditrigonal Prism

Principal forms of the hexagonal system: ditrigonal prism

Principal forms of the isometric system: dodecahedron.

Dodecahedron

Principal forms of the isometric system: dodecahedron.

Showing different types of forms or shapes: rectangle, right triangle, acute triangle, and obtuse triangle.

Forms

Showing different types of forms or shapes: rectangle, right triangle, acute triangle, and obtuse triangle.

Principal forms of the hexagonal system: hexagonal prism

Hexagonal Prism First Order

Principal forms of the hexagonal system: hexagonal prism

Principal forms of the hexagonal system: hexagonal prism

Hexagonal Prism Second Order

Principal forms of the hexagonal system: hexagonal prism

Principal forms of the hexagonal system: hexagonal pyramid.

Hexagonal Pyramid First Order

Principal forms of the hexagonal system: hexagonal pyramid.

Principal forms of the hexagonal system: hexagonal pyramid.

Hexagonal Pyramid Second Order

Principal forms of the hexagonal system: hexagonal pyramid.

Principal forms of the isometric system: hexoctahedron.

Hexoctahedron

Principal forms of the isometric system: hexoctahedron.

Principal forms of the isometric system: hextetrahedron.

Hextetrahedron

Principal forms of the isometric system: hextetrahedron.

"Two forms of the old Greek lyre." -Foster, 1921

Lyre

"Two forms of the old Greek lyre." -Foster, 1921

Principal forms of the isometric system: octahedron.

Octahedron

Principal forms of the isometric system: octahedron.

Principal forms of the isometric system: pyritohedron.

Pyritohedron

Principal forms of the isometric system: pyritohedron.

Principal forms of the isometric system: rectangular prism.

Rectangular Prism

Principal forms of the isometric system: rectangular prism.

Principal forms of the hexagonal system: rhomohedron.

Rhombohedron

Principal forms of the hexagonal system: rhomohedron.

Principal forms of the hexagonal system: scalenohedron

Scalenohedron

Principal forms of the hexagonal system: scalenohedron

"A conduit or canal constructed, especially in a town or city, to carry off superfluous, water, soil, and other matters; a public drain. A, B, C, D, E forms used in London, Paris, and other European cities; F, G, H, I, J, K, L, special forms used in New York and other American cities. F shows a method of repairing with tiles at the bottom of an oval sewer. G, tile-bottomed sewer. H, barrel sewer...of wood bound with iron. I, a form used for large sewers. J, section of pipe sewer. K, half section of sewer having section similar to B, but also provided with a spandrel. L, the aqueduct form, used for large sewers only, it rests on a bed of concrete." —Whitney, 1889

Collection of Sewer Cross-Sections

"A conduit or canal constructed, especially in a town or city, to carry off superfluous, water, soil,…

Four different types of forms or shapes: right triangle, isosceles triangle, rectangle, and circle.

Shapes

Four different types of forms or shapes: right triangle, isosceles triangle, rectangle, and circle.

Principal forms of the isometric system: tetragonal trisoctahedron.

Tetragonal Trisoctahedron

Principal forms of the isometric system: tetragonal trisoctahedron.

Principal forms of the isometric system: tetrahedron.

Tetrahedron

Principal forms of the isometric system: tetrahedron.

Principal forms of the isometric system: tetrahexahedron.

Tetrahexahedron

Principal forms of the isometric system: tetrahexahedron.

Principal forms of the hexagonal system: trigonal prism

Trigonal Prism

Principal forms of the hexagonal system: trigonal prism

Principal forms of the isometric system: trigonal trisoctahedron.

Trigonal Trisoctahedron

Principal forms of the isometric system: trigonal trisoctahedron.

Principal forms of the isometric system: tristetrahedron.

Tristetrahedron

Principal forms of the isometric system: tristetrahedron.