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This striking visual chart, produced under the direction of Samuel W. Stratton at the U.S. Bureau of Standards, is an early 20th-century effort to educate Americans about the structure and logic of the metric system.

Titled International Metric System, the chart blends scientific precision with pedagogical clarity, reflecting a national campaign to familiarize the public and industry with metric measurements. It was issued at a time when the U.S. government was under increasing pressure to modernize and standardize its systems in line with international norms.

The chart uses dimensional illustrations, comparative cylinders, and labeled conversion tables to convey the relationships among metric units of length, area, volume, mass, and capacity. Key visual elements include:

• Graphical Rulers: A metric ruler spanning 0 to 1 meter in decimeters, centimeters, and millimeters, placed above a yardstick for direct comparison.

• Dimensional Cubes and Columns: Showing the equivalency between 1,000 cubic centimeters and 1 liter; 1 liter of water and 1 kilogram; and volumetric comparisons with U.S. quarts (liquid and dry).

• Pound Comparisons: Cylindrical graphs comparing metric grams to U.S. avoirdupois, troy, and apothecary pound systems.

• Metric Prefix Table: An organized prefix system from milli- to kilo-, including examples and conversions to U.S. equivalents.

Intended to be displayed in schools, factories, and scientific institutions to promote literacy in metrication, the image was part of an effort to modernize to the metric system, which the Department of Commerce thought to be a necessary step toward modernization of science, engineering, and trade. 

Though the metric system was developed in revolutionary France in the late 18th century and adopted internationally throughout the 19th century, the United States maintained a complicated relationship with it. The U.S. Congress legalized the use of the metric system in 1866 with the passage of the Metric Act, making it permissible, but not compulsory, to use metric weights and measures in commerce. However, adoption was slow and limited largely to scientific and military circles.

 In 1899, Samuel Wesley Stratton was appointed to lead the U.S. Coast and Geodetic Survey’s Office of Weights and Measures, where he devised a plan for a national standards bureau. With the support of Treasury Secretary Lyman J. Gage, President William McKinley named Stratton the first director of the National Bureau of Standards in 1901, a position he held until 1923. Under his leadership, the Bureau expanded from 24 to 900 employees across 14 buildings and became a hub for recruiting and training young scientists for private industry. Noted as the “lowest-paid corps of first-rank scientists ever assembled by any government,” Stratton’s Bureau conducted research essential to industrial innovation that the private sector alone could not fund. His close collaboration with industry positioned the Bureau as a model of public-private scientific partnership.

Stratton’s contributions were widely recognized by the scientific community. He was elected to the American Philosophical Society in 1904, awarded the Elliott Cresson Medal by the Franklin Institute in 1912, received the Public Welfare Medal from the National Academy of Sciences in 1917, and became an honorary member of The Optical Society in 1922. His departure from government prompted Secretary of Commerce Herbert Hoover to lament the inadequate pay for government scientists.  

Despite these efforts, the United States did not adopt the metric system as its official system of measurement. Opposition from industry, logistical inertia, and cultural resistance hindered progress. Nevertheless, federal agencies—especially in science, engineering, and the military—gradually adopted metric practices, a dual system that persists today.