Dear Greg and All,
I have interspersed some comments.
on 2001-02-20 01.22, Gregory Peterson at [EMAIL PROTECTED] wrote:
> Why not square hectometre (hm²)? The symbol is easily explained as "Hundred
> Metres on each side"
For years the chemists maintained that the decimetre should be taught in
schools to support the cubic decimetre in chemistry. In the meantime the
chemists were rapidly embracing the simplicity of litres, millilitres, and
microlitres.
Similarly, your suggestion would require the teaching of hectometres in
schools to support the concept of square hectometres. And knowing teachers
as I do, they would soon add all of the remaining non-preferred SI prefixes.
There's nothing wrong with the use of these prefixes except it slows down
the adoption of metric and SI dramatically.
True you can say that a hectometre is 100 m on each side. You could just as
easily say that a hectare can be thought of as a square that is 100 m on
each side.
> In a recent conversation with the fellow responsible for water management in
> British Columbia he told me that he was in the process of implementing cubic
> decametres (or square "dekameters" if you choose) for large volumes of water.
> The are practical uses for uncommon SI units. 1 dam³ is approx. 1.2 acre-feet.
This is dangerous ground in terms of conversion to SI. Where there is a
seemingly simple 'conversion factor' it is my experience that it takes much
longer to complete the conversion. Your statement '1 dam³ is approx. 1.2
acre-feet' would have the effect of preserving the acre-feet unit for some
generations of irrigators.
Our experience in Australia is that the adoption of kilolitres and
megalitres avoided conversion factors, so it was possible for irrigation
farmers to adopt a new SI mind-set.
> BTW... cubic decametres is symbolized by dam³. A rather appropriate symbol for
> water management. :)
True, this is amusing, and because of that it would possibly encourage some
to deliberately select the slowest possible path to SI.
> greg
>
>>>> Gene Mechtly <[EMAIL PROTECTED]> 2001-02-16 20:57:48 >>>
> On Fri, 16 Feb 2001, Joseph B. Reid wrote:
>> ... I predict a long life for the nautical mile, knot, and hectare.
> Your prediction might be realized, Joe, but I advocate meter
> squared (m2 as the simplified symbol) for the US, not hectare.
> Gene.
>
Cheers,
Pat Naughtin CAMS
Geelong, Australia
