International yard and pound

Lore & Background

The international yard and pound were established to resolve discrepancies among the imperial standards of length and mass used by English-speaking nations. Prior to the agreement, the United States and the United Kingdom had different definitions: the U.S. These differences caused small but measurable variations in trade and scientific work.

Reader's Guide

customary units, which had diverged since the 19th century. had shifted to metric prototypes after the Treaty of the Metre (1875). The agreement provided a common reference for precise measurements in science, industry, and trade among the six signatory nations. It was adopted by the U.S. The definitions remain in use today, linking customary units to the metric system and ensuring consistency in international commerce and engineering.

Did You Know?

• The international yard is about two millionths of a meter longer than the imperial yard.
• The international pound is about six ten-millionths of a kilogram lighter than the imperial pound.