A polyhedron (plural polyhedra or polyhedrons) is often defined as a geometric object with flat faces and straight edges (the word polyhedron comes from the Classical Greek ÏÎ¿Î»ÏÎµÎ´ÏÎ¿Î½, from poly- , stem of ÏÎ¿Î»ÏÏ, many, + -edron, form of ÎµÎ´ÏÎ¿Î½, base, seat, or face). polyhedron is any three-dimensional figure with flat surfaces that are polygons. Specifically, any geometric shape existing in three-dimensions and having flat faces, each existing in two-dimensions, which intersect at straight, linear edges.
In 1839, Charles Goodyear invented rubber vulcanization, but the first rubber condom was not produced until 1855. Just a few short years later, the majority of rubber companies were producing condoms as well. These condoms were reusable, which meant they were much more affordable.
by Tomo Â· March 23, 2011. A German named Charles Wiesenthal who lived in England got patented the needle that he designed for sewing machine in 1755. It was in 1790 Thomas Saint, who was an English inventor and a maker of cabinets got a copyright for a sewing machine as a whole.homas Stone and James Henderson got French patent for their machine and Scott John Duncans for his embroidery machine in 1804 but both machines were a great failure. The French tailor Barthelemy Thimonnier invented the first sewing machine that could function in 1830.