[USMA:42895] Re: ectare was: An Associated Press article

[Jon Saxton]

I respectfully disagree. There is a fundamental problem with the "rule of 1000" when applied to powers of units.  "Rule of 1000" becomes "rule of 1 000 000" for area and "rule of 1 000 000 000" for volume so it is fairly obvious that we need some intermediate units for common sizes.  The litre/liter for volume is a good example. The hectare works for land and is easy to visualise (100 m x 100 m).  Whether 10 x100 or 20 x 50 is easier or harder is incidental.  Area is actually more problematic than volume because we like to think in squares and 1000 is not a square. What do you think would be a good unit for measuring the area of video screens?  mm² is too small for your television and m² impractical for your iPod.  Even cm² is probably too small for TV screens.  A practical unit might be dm² - that would give screen sizes in the range 0.2 dm² to 200 dm² for the most part. In the case of area you have to abandon one concept or the other.  If you want neat squares for area then the rule of 1000 has to be replaced by a rule of 100.  If you want to adhere religiously to the rule of 1000 then you have to give up square units of area. Pierre Abbat wrote: On Sunday 25 January 2009 20:24:12 STANLEY DOORE wrote: Hectare is just another name and conversion to learn, remember and visualize. I think the hectare ought to be scrapped. If any unit of area should have a special name, it's the dunam, or stremma, which is 1000 m²*, which follows the rule of 1000. A gigadunam is a square megameter. Neither the gigare nor the megare is the square of any named unit. This would give a name to the unit midway between the square kilometer and the square megameter. Lake Superior is 82.4 megadunams. A hectare-millimeter is 10 m³, which isn't the cube of anything rational, nor does it have a unit name. A dunam-millimeter is a cubic meter, which is a kiloliter. For people who think in powers of 1000, the latter is easier. *Except in Iraq, but the Iraqis should abolish their own special dunam and use the same one as their neighbors. Pierre