The Union chain represents the knotted cord that runs around the temple walls. This cord is interlaced at equal intervals. It is also represented on numerous engravings illustrating Masonic scenes, or embroidered on master’s aprons. It indicates that we are all links belonging to the same chain. For the companions it is an indispensable tool to measure angles, for the Freemasons it symbolises the chain of union.
The Union Chain, according to its definition, brings together and unites.

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