Scale Rules

Length Measures

Although shared words for units of measurement—typically body parts such as "hand" and "foot"—dated back to ancient times, the lengths of these units differed by local custom. By the 17th and 18th centuries, each European city had its own standard for length measures. Many places called this standard an "ell," although the spelling of the word varied. When this Museum opened in 1964, the curators collected original objects and reproductions to show how the mathematics of European daily life had been transported into American business and trade. One particular treasure is a pedometer made by Jacob Ramminger in Stuttgart, Germany, around 1600.

As national states unified formerly decentralized localities and as trade between different areas of Europe increased, governments made efforts to define national standards. The English lengths for the inch, foot, and yard were perhaps most prominent around the world, and they were utilized in the American colonies. In both the Articles of Confederation and the U.S. Constitution, the federal government reserved for itself the power to fix national weights and measures. Shortly thereafter, in the 1790s, scientists working for the French government developed the metric system, in which one meter represented one ten-millionth of the distance between the North Pole and the Equator. Although copies of metric standards were brought to the United States, Americans maintained a complicated relationship with the system of measurement. For instance, John Quincy Adams investigated the system in 1821; Charles Davies evaluated it again in 1867. Both men recommended that adoption of metric measurements be delayed since English units were so well established in American commerce.

In addition to examples of yard and meter standards from the 19th and 20th centuries and other efforts to promote the metric system, the collection has one of the rules Scottish Astronomer Royal Charles Piazzi Smyth distributed in an unsuccessful effort to prove that the system of measurement used by ancient Egyptians to build the pyramids correlated with the modern English system. There are also several rulers brought by the nation of Japan to the 1876 World's Fair to demonstrate its ability to adopt European units. Finally, this page contains some rules made by the notable American manufacturers Stanley and Lufkin and some rulers used in schools.