Mechanics illustrations, 19th century. Across top are three types of lever, with the weights and pivots in different locations. Below these are several systems of pulleys and a weighing balance. Below these, at left, is a wheel and axle, referred to by the archaic term 'axis in peritrochio'. To the right of that are two types of inclined plane (standard and double). Across bottom are three types of screw (screw press, common screw and endless screw), together with a wedge. This page is from 'Universal Technological Dictionary' (1823) by British author George Crabb (1778-1851).