DENIS SMITH wrote:

I guess the real issue is that whatever we use we
should stick with it.  Ask the guys that landed the
planetary probe many feet/meters below the surface
because they weren't sure whether to use feet or
meters.  A kings foot?  Wonder where the meter came
from.  Someone with a longer arm than the king??

I do not know where the meter ( incidently the SI guys want us to spell
it metre) came from,
but the standard for many years was a platinum rod in Paris (if you could
trust those guys
not to file a bit off the end to make a ring for his lady love). As I
understand, the first
precision standard was to set 25.4 millimeters to the inch, (with no
trailing decimals)
since the inch was more precisely standardized at that time because of
interchangibilty
of assembly in the later part of the industial revoloution (not invented
by the metric guys).
Current standard, I believe is set by wavelengths of a very monochromatic
light
(Maybe sodium)-

Incidently when the military tried unsuccessfully to metrify the
Peacekeeper program, I wrote
a program in BASIC which would read a ASCI text file and identify
measurements in the
English system - convert to SI units - print the new text in - with the
original units and
values in parenthesis, like NASA likes it done. I dug this progam back
out of a 5 inch
floppy to satisfy some of the requirements of the light weight wing
program that Rich
and I worked on. - By the way, does anyone off hand know the breaking
strength of carbon
fiber in Pascals? - let me see? a Newton, which is about equivalent to
the weight of an apple,
spread over an area just a bit larger than a yard of carpet  - oh yes!!!
I see it clearly now!!

Vance

 
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