On 04/06/12 15:07, James Knott wrote: > Mike Scott wrote: >> No way!!! Remind us what the original intent of the metre was - and >> how wrong (and pointless). And the current definition is, well, >> arbitrary, is it not? >> >> And how do entities like the litres and are fit into a "rational" >> system that already has cubic this and square that? > > The original "metre" was 1/10,000,000 the distance between the equator > and pole. It was later refined to the distance light travels in 1 ⁄ As I said, arbitrary, and pointless. > 299,792,458 second. The second is defined by the oscillations of the > cesium atom. Now consider water. One millilitre (1 cm³ or cc) has a mass > of 1 gram. Approximately. But so what? > .... A litre = 1000 cc and 1 Kg. Nice and convenient that. Now > what about the weight and dimensions of an ounce of water? U.S. vs A pint of water weighs a pound and a quarter. At least, on my side of the Atlantic. It even rhymes. A fluid ounce of water is just that - an ounce. (Although you then land with asking about at what temperature and pressure - just as with mg and ml (or is that cc? See? :-) ) But a litre = 1000cc - so what? It's an introduction of another pseudo-fundamental unit, because it's "about the right size" for real use (a cubic metre is rather a lot :-) ). Rather like the imperial system, I find. Similarly with the are (which I had to look up - a square decametre) > imperial ounce? U.S. or imperial quart? Gallon? When you work in science > or engineering the metric system works out extremely well due to the > easy scaling. You certainly can't say the same for the various > traditional units. I wouldn't try to. My point is that the metric system is fundamentally just as irrational, and twice as pointless :-) For my own part, I do as I'd advice others: use whichever is convenient for the job in hand. And don't mix 'em. You make expensive craters on Mars like that :-} -- Mike Scott Harlow, Essex, England --------------------------------------------------------------------- To unsubscribe, e-mail: ooo-users-unsubscribe@incubator.apache.org For additional commands, e-mail: ooo-users-help@incubator.apache.org