Alqueire

The term alqueire is documented in Portugal since the 12th century. It derives from the Arabic al kayl, which designated originally the satchels or baskets carried by pack animals for the transport of goods. The capacity of those satchels, more or less standardized by the ability of the pack animals, was taken as a measure of dry goods, especially grain. In Portugal, it was used as a measure of capacity and, eventually, it was used also as a measure of area of productive land. The spread of Portuguese culture took both meanings of the word to different parts of the world.

The Arabic al-kayl, used in areas of the Iberian Peninsula under Arab rule, was imported to northern Portugal around the time of the Portuguese County, where it became known as alqueire. The first explicit reference dates from 1111, but the alqueire was alreay in use in the late 11th century. Most likely, the term alqueire designated a single well-known measure in the Portuguese County. Half century later, in 1145, the municipal ordinances of Coimbra stipulated that the alqueire (of cereal) should have a weight of 6.5 arráteis, and thus a capacity for around 3.4 liters. This probably indicates that other alqueires were starting to be used in parallel with the standard.

Throughout most of the first dynasty, reigns of Afonso Henriques to Afonso IV, the legal alqueire was equivalent to the Roman modius, i.e. about 8.7 liters. However, the legal alqueire was not used throughout the whole country. King Pedro I (1357) introduced a new alqueire of 9.8 liters and tried to impose it as a standard for the whole kingdom. This alqueire in fact had a wider spread than the previous one, but failed to generalize to the entire territory. With Manuel I (1499), the alqueire of Lisbon, which amounted to 13.1 liters, became the standard for the kingdom. Sebastião I (1575) distributed copies of this standard, in bronze, to the main towns of the kingdom. However, regional standards still survived. Later, probably following the 1755 earthquake, the capacity of the alqueire of Lisbon was adjusted, approaching the 13.9 liters, which would allow easier conversion to the Spanish system.

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