This follows on from my post yesterday about sterling vs decimal currency. I’m going to move onto imperial vs metric units, another bone of contention among the die-hard harrumphers.

We still have miles, we still have pints in the pub. But for pretty much everything else we use metric units. There’s a good reason for this. We trade with the rest of the world, the rest of the world works in metric. Well mostly. The US doesn’t. But there are problems there too, as I’ll get onto.

The beloved yard was the length between the raised thumb on a straight arm and the end of the nose. Not any old thumb and nose, oh no. They were attached to King Henry I, though there had been a yardstick that the Saxon king Edgar kept at Winchester, the then capital city.

The foot was one of Henry’s too. The inch was the length of the distal portion of his thumb. His thumbs saw some action didn’t they? There we were stuck with measurements based on bodyparts of a medieval king. Could have been worse, if you think about it.

Oh yes, an inch was further defined as ‘three grains of barley, dry and round.’ Now you know in units you can relate to just how big Hal’s thumbs were.

We cheated when we adopted metric anyway. We just made things the metric equivalent of things we were already familiar with. A 4”x4” piece of timber is now a 10.16cmx10.16cm piece of timber. Same size, different notation. Plasterboard comes in the same size it ever was, which was 8’x4’, but now it’s sold by the metric equivalent of that. This was useful for me when I did a lot of DIY and a lot of the available ‘how to’ videos were of American origin, and I didn’t need to worry.

The ounce was defined as 1/20th the weight of a pint of water, for some reason. Then there was the difference between avoirdupois and troy weight. In the latter, used for precious metals, there are 20 not 16 ounces to the pound. Hence a pound of gold really does weigh more than a pound of feathers.

In the US they still muck about with pints and stuff, but when they gained independence they went to town a bit. A US pint is only 16 fl oz, so when I go there and have a pint I feel as if I’ve been sold short, since my pint has 20 fl oz in it. The American ton is 2000lbs. In the UK that’s known as a short ton, since 20 hundredweight (I forgot to mention that one, but it’s 112lb not the 100lb you might reasonably expect) is 2240lb.

By odd coincidence, that’s near enough a metric tonne. A US ton is only 90% of a metric tonne.

Hence my lack of enthusiasm for a return to the good old days. I remember slogging through all manner of crap at school calculating the cost of however many stone (14lbs, 8 to the hundredweight) of something at £1 3s 7d a pound.