Metric Historical Time Line
3,000
B.C.
Development of the Egyptian cubit (524 mm),
taken as the length of an arm from the elbow
to the extended fingertips. The Egyptian cubit
could be further divided into 28 digits, or
28 breadths of a finger.
1,700
B.C.
The Babylonian cubit (530 mm) was developed.
1,000
B.C.
The Greek cubit was developed, based on the
concepts of the Egyptian and Babylonian cubits.
500 B.C.
The Roman foot was developed and could be subdivided
into 12 equal inches. One pace equaled 5 feet,
so 1,000 paces equaled 1 mile or 5,000 feet,
similar to our 5,280-foot mile.
1202
Italian mathematician Leonardo of Pisa wrote
Book of the Abacus, explaining the idea of a
decimal-based system.
1585
Simon Stevin suggested the use of the decimal
system for weights, measures, coinage and divisions
of the degree of arc in his book “The
Tenth”.
1670
Gabriel Mount, a French vicar, proposed a uniform
measure defined by the length of one minute
of the Earth’s arc, which could then be
divided decimally (10s, 100s, 1,000s, etc.).
1791
Jean Charles de Borda, chairman of the Commission
of Weights and Measures, proposed using Mount’s
idea. Borda suggested using the length of one
ten-millionth of the distance from the North
Pole to the equator. This distance would be
determined by a survey along the meridian through
France between Dunkerque and Barcelona.
1792-1799
Mr. Delambre and Mr. Mechain measured the length
of the Earth’s Meridian between Dunkerque,
France, and Barcelona, Spain.
1792
U.S. Mint formed to produce the world’s
first decimal currency.
1795
France officially adopted the metric system.
1812
Napoleon suspended the compulsory provisions
of the 1795 metric system adoption in France.
1821
John Quincy Adams presented a four-year study
on the metric system and modernization of the
measurement system concluding that the United
States should adopt the metric system, but hinted
that the metric system was still young and needed
time to mature.
1840
The metric system reinstated as the compulsory
system in France.
1866
The use of the metric system was made legal
but not mandatory in the United States by the
Metric Act of 1866 (P.L. 39-183).
1875
The United States is one of the original 17
signatory nations to the Treaty of the Meter,
which created the General Conference on Weights
and Measures (CGPM).
1893
The Coast and Geodetic Survey published Bulletin
26, “Fundamental Standards of Length and
Mass,” which made the new metric standards
the official standards of weights and measures
in the United States. All old non-metric units
were then redefined in terms of the new metric
standards; for example, 1 inch was redefined
as 0.0254 m and 1 pound was redefined as 0.45359237
kg. So in actuality our standard inch and pound
have been defined in terms of the metric system
for the past 110 years.
1916
U.S. Metric Association formed.
1960
The 11th CGPM introduced the “Systéme
International d’Unités” (SI
for short) that consisted of the six base units
(meter, kilogram, second, ampere, Kelvin and
candela) and the prefixes pico through tera.
1975
The Metric Conversion Act (P.L. 94-168) passed
by U.S. Congress.
1988
Omnibus Trade and Competitiveness Act of 1988
(P.L. 100-418) mandated that all federal agencies
implement the metric system in procurement,
grants and other business related activities
by the end of 1992.
1991
President George Bush signed Executive Order
12770, Metric Usage in Federal Government Programs.
1996
Cox Bill (P.L. 104-289) signed, which prohibited
federal contract documents from solely specifying
concrete masonry units in modular metric sizes.
1998
Transportation Equity Act for the 21st Century
removed the target date for metric conversion,
thereby allowing state DOTs the option of converting
to the International System of Measurements.
