John S, makes a number of very valid points and in a well laid out manner. I have lived in all worlds. I grew up in the UK with imperial dominant until I left in 1981. I arrived in a fully metricated South Africa and so my conversion was by total immersion and the process was rapid and mostly painless. It was a new world, a new system and there was no need for comparisons or conversions. I found myself thinking and judging metric and would estimate time and distance with reasonable accuracy in kilometres. Interestingly (for me at least [Linked Image] ) was that on trips back to the UK it seemed so natural to do the same in miles.

On the metricated imperial units side, the beer in RSA, in returnable bottles, came in two sizes – one called pints with 375ml and the other called a quart with only 750ml. I mentioned to my friends that the UK WMA would have serious problems with these interpretations! Having a ‘pint’ of cold draught beer in a pub measuring 500ml did not make the experience any less enjoyable. [Linked Image]

Then move to the US where the measurement system is in state of turmoil. The world of science has long been metric and that of technology mainly so. Remember the Mars lander? NAFTA means that metric measurements appear on every item sold in addition to what the Americans refer to as ‘English’ units. This can be very strange to an Englishman because a lot of these units are not the same as those I grew up with. Most noticeable are the volume measures which are 20% smaller – it makes the gallon to litre conversion much easier. I think those British traders were ripping off the colonists – no wonder they revolted!

The mining industry, of which I am a part, is very conservative in its ways and sticks doggedly to the old units. Everything is measured in feet, plans are scaled in inches per X foot so a plan with a scale of 1:1000 is in fact a 1:12000 plan! Gold grades are measured in ounces (troy) per ton (short, 2000lbs) rather than grams per tonne which also equals a useful parts-per-million. I remember in my early days here listening to a surveyor trying to get his head around some borehole maths involving volume measurements with the length in feet, the diameter in inches, the volume in gallons and the weight of additive for a certain concentration given in pounds – he needed a concentration in relative mass by percent. I heard his demented utterings and saw his tortured face and said helpfully “why don’t you just metricate?”

Another difference I have observed is the depreciated use of the yard and long (2240lbs) ton. A sign in my town says Parking – 1000 feet which I find hard to visualise and vehicle weights are given in thousands of pounds rather than tons – a forty ton truck has a lot of zeros on the plate! The US sticking to ‘English’ measures is strange because in many ways they have metricated in so many ways so long ago. The dollar and cents must be one of the first (if not the oldest) metric currency in the world. The hundred weight is 100lbs, etc.

Getting back to South Africa, one had to be careful when converting from pre-metric data because in Natal were I lived they used the Cape Foot which is about 13” sterling. To complicate my life further (which it did), I discovered the Cape Geodetic Foot used in land measurement which differed from the normal Cape Foot only in the seventh decimal metric. Not much you would say, however when the Mercator grid system used there has its origins at the equator, that seventh decimal place adds up. Needless to say I drilled a borehole off by 15m which put me on the wrong farm. Oh the legal torture that caused is fused into my memory – why did I have to pick the most obnoxious and canterkerous farmer in the Province?

I can’t remember whether I’ve mentioned this before on the forum, but I’ll repeat it again because I find it so fundamental and pedestal smashing amongst the traditionalists. Very few conversions from imperial to metric are exact and I suspect many are not even rational (mathematically speaking), but one is. The foot is exactly 304.8mm long, i.e. an inch is exactly 25.4mm. This conversion defines the US survey foot which is the same as the official imperial foot. This is not by chance and was it defined long after the metre was established and standardised. The awesome (for me) truth is that the unit underlying the definition of the good old foot lies not in the Tower of London but is in fact in Paris, i.e. it is the metre!

IMHO, metric is best. There is only one way to change and that is total immersion. The South African way of making all imperially marked objects illegal is way OTT (my wife when a school girl had a six inch marked ruler sent by her UK Granny confiscated by customs). But then the Afrikaner was wanting to rid the country of all things British.

I reckon the way that the Australians did it was the best. Big bang – fully metric but inches and imperial tools can still be found and 2 by 4s are still called 2 by 4s. My Zulu gardener still worked financially in bob up to the early 1990’s. “Ten bob” (10/-) said Pete – it meant one rand. When the South Africans jettisoned the pound, they did it at the rate of £1 = R2. Made life slightly easier on the shillings and pence.

Anyway that’s my 2d worth – which by my reckoning is worth 1.2p!


[This message has been edited by Hutch (edited 09-01-2003).]