Plumb rule
A plumb rule, used by builders to test that a wall is upright. Masons read it as uprightness of conduct.
Meaning
For today's Freemasons the plumb is a symbol of justice, rectitude and the importance of living in an upright manner, the Grand Lodge of California explains. George Thornburgh's 1903 monitor gives it to the Fellow Craft as a working tool, with the words 'The Plumb admonishes us to walk uprightly in our several stations before God and man'. Albert Mackey's word for it was rectitude.
Origin and history
The plumb was among the first tools the early Masonic texts name. A text of 1725 says a lodge is governed 'Of Square Plumb and Rule', and by 1730 the explanations were close to today's: the level 'to try all Horizontals, and the Plumb-Rule to try all Uprights', as Harry Carr of the Quatuor Coronati research lodge traced.
Write in the Freemasons’ cipher
stringmash.comPigpen cipherThe grid cipher once used for lodge records, drawn from any text you type.See also
Level, Square and compasses, The letter G, All-seeing eye, Double-headed eagle, Boaz and Jachin.
Sources
- Freemasonry Symbols, Masons of California (Grand Lodge of California)
- Masonic Monitor of the Degrees of Entered Apprentice, Fellow Craft and Master Mason, George Thornburgh, 1903, approved by the Grand Lodge of Arkansas, Project Gutenberg, Fellow Craft degree
- The Symbolism of Freemasonry, Albert G. Mackey, 1869, Project Gutenberg, Chapter XI
- Origin of the Working Tools, Harry Carr (ed.), Ars Quatuor Coronatorum, vol. 78 (1965), pp. 278–80, Grand Lodge of British Columbia and Yukon
Last reviewed September 25, 2026 by Rory Hansen. How we research