megaohm). There are exceptions, though, especially if the resulting prefix and unit
sound fine, such as a milliampere. There are even times that another letter is added to
make it easier to roll off the tongue. For example, the letter “l” is added to the term for
1 million ergs, making it a megalerg, not a megaerg or megerg.
How did the metric system originate?
In 1791 the French Revolution was in full swing when the metric system was pro-
posed as a much needed plan to bring order to the many conflicting systems of
weights and measures used throughout Europe. It would eventually replace all the
traditional units (except those for time and angle measurements).
The system was adopted by the French revolutionary assembly in 1795; and the
standard meter (the first metric standard) was adopted in 1799. But not everyone
agreed with the metric system’s use, and it took several decades before many Euro-
pean governments adopted the system. By 1820 Belgium, the Netherlands, and Lux-
embourg all required the use of the metric system. France, the originator of the sys-
tem and its standards, took longer, finally making metric mandatory in 1837. Other
countries such as Sweden were even slower. They accepted the system by 1878 and
took another ten years to change from the old method to the metric.
How did the first standard metric measurements evolveover time?
The first standard metric units were developed by 1799: The meter was defined as one
ten-millionth of the distance from the equator to the North Pole; the liter was defined 53
MATHEMATICS THROUGHOUT HISTORY
Is it possible to convert international units seen on such items
as vitamin bottles to milligrams or micrograms?N
o, there is no direct way to convert international units (IU) to mass units,
such as milligrams. Most familiar to people who read vitamin and mineral
bottles, an IU has nothing to do with weight; it is merely the measure of a drug
or vitamin’s potency or effect. Although it is possible to convert some items’ IUs
to a weight measurement, there is no consistent number. This is because not all
materials weigh the same and the preparation of substances vary, making the
total weights of one preparation differ from another.
But there are some substances that can be converted, because for each sub-
stance there is an international agreement specifying the biological effect
expected with a dose of 1 IU. For example, for vitamins, 1 IU of vitamin E equals
0.667 milligrams (mg); 1 IU of Vitamin C is equal to 0.05 mg. In terms of drugs,
1 IU of standard preparation insulin represents 45.5 micrograms; 1 IU of stan-
dard preparation penicillin equals 0.6 micrograms.