On 2014-01-08, at 20:55, Steve Smith wrote:
> There's this thing we call irony... check it out, you might like it.
>
Even though iron pipe has been supplanted by plastic in many applications.
> On 1/8/2014 22:37, Robert A. Rosenberg wrote:
>>
>>>
>>> "Half inch or three-quarters?"
>>
>> I see no problem with the question. The pipe is still made in half
>> and three-quarter diameters (not metric diameters) since it is a
>> standard item and needs to work with older fittings/etc. The lengths
>> however have switched over to metric lengths.
>>
Sometimes the tradition persists; sometimes not. A few decades ago,
I went to purchase a bicycle freewheel. The clerk asked me, "American
or French wheel?" 24 threads per inch vs. mm.
And we might soon have a physical standard of mass:
http://en.wikipedia.org/wiki/Kilogram
http://www.youtube.com/watch?v=ZMByI4s-D-Y
-- gil
