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Mathematics Throughout History

Development Ofweights and Measures

What were some early measurements of volume in terms of the gallon?

The names of the traditional volume units are the names of standard containers. Until the 18th century, the capacity of a container was difficult to accurately measure in cubic units. Thus, the standard containers were defined by the weight of a particular substance—such as wheat or beer—that the container could carry. For example, the basic English unit of volume, or the gallon, was originally defined as the volume of eight pounds of wheat. Other volumes were measured based on this gallon, depending on the different standard sizes of the containers.

But like most measurements over time, not all gallons were alike. During the American colonial period, the gallons from British commerce were based on dry and liquid commodities. For dry, the gallon was 1/8th of a Winchester bushel (defined by the English Parliament in 1696 as a cylindrical container 18.5 inches in diameter by 8 inches deep), holding 268.8 cubic inches of material; it was also called a “corn gallon” in England. For liquid, the gallon measurement was based on England’s Queen Anne’s wine gallon (also called the traditional British wine gallon), measuring exactly 231 cubic inches. This is why volume measurements in the United States include both the dry and liquid units, the dry units being about one-sixth larger than the corresponding liquid units.

By 1824, the British weren’t as satisfied with the gallon divisions as the Americans. In response, the British Parliament abolished all the traditional gallons and established a system based on the Imperial gallon. It is still in use today, measuring 277.42 cubic inches, with the container holding exactly 10 pounds of water under specific (such as temperature and pressure) conditions.