When following a c, an i or e makes the c soft, so an er ending would change the pronunciation. That is why acre, lucre, and a few other words are exceptions. Didn't your mothre or fathre teach you that?
It is NOT only the metric words that er/re differences, have you considered the center of a circle, or tire vs tyre? No, because you are on a vendetta about metres, and prefer Customary to meters. I grant you when used as part of a proper noun (name of a specific establishment), there are some pretentious Centres and Theatres in the US but center and theater are used by many more, and generically, as well. >________________________________ > From: Harold_Potsdamer <harold_potsda...@cox.net> >To: U.S. Metric Association <usma@colostate.edu> >Sent: Thursday, June 26, 2014 8:52 PM >Subject: [USMA:54063] Re: Example of problem with round off errors, etc. > > > >This is very common. > >I’ve seen increments of 25 mm converted to rounded increments of 1 inch then back converted to increments of 25.4 mm. > >Changing –re to –er only applies to metric units, so it can be made to appear that metric units are inconsistent. Luddites want to keep acre spelled with an –re because it is quaint and traditional. > >Funny how the claim of so-called American metric promoters insist without a shred of proof that –re spelling will scare Americans away from metric, but the American public isn’t scared away from acres with their –re spelling. Repeating a lie over and over never makes it true. > > >From: Parker Willey Jr. >Sent: Thursday, 2014-06-26 17:54 >To: U.S. Metric Association >Subject: [USMA:54055] Example of problem with round off errors, etc. > Hi: > > >Suppose someone takes a 1 liter bottle of Safflower seed oil and converts the label info to legacy units for sale in the US. > >Then later, someone else wants to put on the label metric units, uses the legacy info and converts it back resulting in a round off error. > >See the attached picture. > > >Also, in the discussion about "er" vs "re" endings on units of measure, you remember the legacy unit of land area: acre. It is defined as 43560 legacy square feet. Anyway, should it be spelled "acer". > >Just a tidbit. > >...Parker Willey Jr. >San Jose, CA > >