The seal was adopted by City Council on Feb. 14, 1874. Its centerpiece is a shield displaying a ship under full sail at the bottom and a plow above.
The ship was the symbol of the Free Society of Traders, a London business organization that promoted the colony of Pennsylvania (and gave its name to Society Hill). The vessel also represents commerce. The plow is the symbol that WIlliam Penn assigned to Chester County. It is also a general heraldic symbol for agriculture, which was very important in the settlement and history of Pennsylvania.
Two Female figures flank the shield. The one on the left wears an olive garland and holds a scroll inscribed with an anchor. The garland signifies peace, and the anchor also signifies hope. The figure on the right holds a cornucopia, symbolizing abundance.
Above the shield appears a bent arm holding the scales of justice and mercy, and below is a macaronic phrase containing the greek and latin words Philadelphia Maneto - "Let Brotherly Love Continue". The words come from the New Testament - Hebrews 13:1 - and are said to have been uttered by the last of the Penns visiting Philadelphia in the 19th century.
The seal's blue and gold are the city's colors. Blue the color of the heavens, stands for aspiration. Gold signifies high worth.