You can tell a lot from a doorway in the hutongs of Beijing. First there is the little plaque with the character for either public or private, denoting ownership. Next there are decoration knobs above the door. Two green knobs denote a common person whilst four blue ones denote a richer person and twelve are reserved for the emperor. Looking to the two stone decorations guarding the threshold gives a clue to the occupation of the former owners. Rectangular ones represent scroll boxes suggesting a scholar or official whereas round ones are meant to be war drums and so a military officer.

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