It's a definition, was Re: Conversion

Hi,

For a unit of measure to be a standard, it had to be reproduceable
accurately anywhere with simple equipment. 100F was thought to be
normal body temperature, 0F was supposedly the coldest possible man-
made temperature, a salt and ice mixture. Turned out not to be so.

The same goes for metric units. A meter was supposed to be 1 ten-
millionth of the distance from the North pole to the South pole.
Turns out not to be so either.

Mariss



--- In CAD_CAM_EDM_DRO@y..., Randy Gordon-Gilmore <zephyrus@r...>
wrote:

> The metric to inch conversion at 1" = .0254m is a legal and exact
> definition since 1959.
>
> http://physics.nist.gov/Pubs/SP811/appenB9.html
>
> is the closest I know of to a definitive reference in the US for

metric

> conversion factors.
>
> "Factors in boldface are exact," others are rounded.
>
> Best regards,
>
> Randy
>
> Randy Gordon-Gilmore ,----.___________ ______________

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