I’m a little confused, I confess, about what measurements are or are not legal tender in this country now. I am told by our local authority that I live 9 kilometres (or worse, ‘9K’) from our nearest town. It has been six miles throughout history: has there been an Act of Parliament to change it, or is it just the itch to modernize on the part of our public servants?
I suppose it doesn’t really matter much, and we shall scrub along with old and new together for many years to come. It does matter, though, at least to me, in my writing. Compose a readable sentence involving two measurement systems if you can; the brackets round the alternatives are always ugly and intrusive, interrupt the rhythm and confuse the sense.
The moment has come to decide which system, Imperial or metric, to use in the book I am writing: a new edition of my old International Book of Trees. (Very old: it was born in 1973.) My publisher naturally would like to go metric. I demur, on the basis that a metre is too big a unit to visualize with any accuracy, and a millimetre far too small. I see nothing wrong with a centimetre, but no advantage, either, over an inch.
The test is (or should be) how usable your measures are in practice, which depends on the scale of what you are measuring. A shrub which is four feet high, let’s say, is much less graphically described as 1200 millimetres, or 1.2 metres. You wear a foot, in case of doubt, on the end of each leg for ready reference, and your forearm is eighteen inches, or a foot and a half, long, more or less. You rarely need a tape-measure in an antique shop: old furniture is nearly always either one, two or three forearms (or cubits) wide.
Do bigger objects need bigger measures? A tree one hundred feet high is 30.48 metres – or call it 30 for tidiness. (Which is more important, a figure you can remember or one that is accurate to two decimal points?). Which sounds more interesting, as though it had reached a rather splendid height? It depends, I suppose, on where you were born and educated, but if you have a metric heart you have to be either very excitable (Great Scot! Thirty metres!) or very patient. Weather forecasters, you will have noticed, rarely forebear to mention when the temperature nears 100 degrees Fahrenheit.
Do you detect me deciding on the old money solution? I don’t expect to get an easy ride.