Roller chain or bush roller chain is the type of chain drive most commonly used for transmission of mechanical power on many kinds of domestic, industrial and agricultural machinery, including conveyors, wire- and tube-drawing machines, printing presses, cars, motorcycles, and bicycles.
Pietra dura (Italian: [ËpjÉËtra ËduËra]) or pietre dure [ËpjÉËtre ËduËre] (see below), called parchin kari or parchinkari in South Asia, is a term for the inlay technique of using cut and fitted, highly polished colored stones to create images. It is considered a decorative art.
The Triquetra is an ancient symbol consisting of three vesica pices interlocked in an eternal arc and sometimes enclosed within a circle to represent unity.The Triquetra is typically used to symbolize people or ideas occurring in a group of three.he unique interweaving of the Triquetra symbolizes unity and indivisibility. The Triquetra, as a symbol of the Trinity was used commonly by the Celtic Christian Church and sometimes represented by three interlaced fish within a circle representing unity.