Metric system

Australia

France

Rumania

New Zealand

Mexico

I am highly interested in promoting the metric system. For this reason, studying stamps that commemorate a country's adopting the metric system is one of my primary interests in philately. Accordingly, I have made a special effort to collect such stamps, and I post my so far meager collection here. To see an excellent set of metric-related stamps, along with a thorough discussion of them, I refer you to the article by Donald W. Hillger and Louis F. Sokol, "The Modern Metric System on Postage Stamps," published in the Journal of Chemical Education 65:5 (May 1988): 384-387. Hillger is the webmaster of the U.S. Metric Association.

Scott #541 - #544

In 1973, metric weights and measurements were introduced in Australian post offices. The following four stamps comprise a series issued to commemorate that event, and to assist Australians adapt to the metric system. Without question, they nicely exemplify how postage stamps can be used as an educational tool.

Scott #732

In 1954, France issued this stamp to commemorate its adoption of the metric system in the 1790s. French surveyors developed the system, and France was the first country in the world to adopt it. Translating from the French, the stamp reads, "For all people, for all time." According to Ken Alder, a science historian, Condorcet probably coined this phrase in the period from 1791 to 1794.

Notice that the person is measuring one-quarter of the earth's circumference. Initially, one ten-millionth of this distance was set to be the length of a meter. Hence, 10 000 000 m, or 10 000 km, was reckoned as the distance from the equator to the North Pole. (But we could just as easily say that a quarter of any great circle amounted to that distance.) Through more accurate calculations, the distance has been determined to be a bit more — about 10 009 km.

Scott #1873 or #1874

To celebrate the centenary of its conversion to the metric system, Rumania issue this and the next stamp. Notice how this stamp, like the French one above, also shows the measurement of the globe's quadrant, and it indicates a length of 10 000 000 m.

Incidentally, both of the Rumanian stamps are cancelled to order. This is not my collecting desire, but it is all I have been able to find.

Scott #1873 or #1874

This stamp, like the previous one, commemorating the centennial of Rumania's adopting the metric system. The design shows the seven base units of measurement surrounding the letters 'SI'. The surrounding letters designate kilogram, meter, ampere, kelvin (but now used without the degree symbol), candela, and second.

Scott #594

To announce its changeover to the metric system in 1976, New Zealand issued this stamp showing a stylized 'M'. The stamp also shows some kind of vessel containing a liquid as well as a ruler with presumably metric units.

I did not run EzGrader on this stamp since it is a block of four, and EzGrader is only designed to analyze individual stamps. By my own measurement, however, the stamp is 40 mm × 24 mm to the nearest millimeter.