Jerry, True, the "meter" is intended to be a length which is *constant* in time.
It is only the definitions for *realization* of this constant length which have been improved over the years. You can read the historical development of the definitions of the meter and all other SI units in the BIPM brochure or in NIST documents. Search the Internet for BIPM or NIST SP 330 (2008 Edition). Gene. ---- Original message ---- >Date: Fri, 30 Jan 2009 19:32:10 -0800 (PST) >From: Jeremiah MacGregor <[email protected]> >Subject: [USMA:42642] Re: Going metric would be nice global gesture | ajc.com >To: "U.S. Metric Association" <[email protected]> ... > I didn't think the meter ever changed and is the same today > as it was in > 1795. >... > Is there some way of knowing for sure? > > Jerry
