The units of measurement of ancient Rome were generally consistent and well documented.
The units of measurement of ancient Rome were generally consistent and well documented.
The siliqua (pl. siliquas or siliquae) is the modern name—given without any ancient evidence to confirm the designation—to small, thin, Roman silver coins produced in the 4th century and later. When the coins were in circulation, the Latin word siliqua was a unit of weight or value defined by one late Roman writer as one twenty-fourth of a Roman solidus.
The term siliqua comes from the siliqua graeca, the seed of the carob tree, which in the Roman weight system is equivalent to 1⁄6 of a scruple (1⁄1728 of a Roman pound or about 0.19 grams).
Both the British imperial measurement system and United States customary systems of measurement derive from earlier English unit systems used prior to 1824 that were the result of a combination of the local Anglo-Saxon units inherited from Germanic tribes and Roman units.
Having this shared heritage, the two systems are quite similar, but there are differences. The US customary system is based on English systems of the 18th century, while the imperial system was defined in 1824, almost a half-century after American independence.