Metric mystery

Nicholas Kerr cries out against the metric mystery which has us using two systems at once.

Two jugs of supermarket own brand milk, one is 4 pints, the other 2 litres.

Kent Bylines recently published an article by Charlotte Lebon about the mystery surrounding liquid measure and lamenting the use of units other than metric ones. I heartily agree with her sentiment.

It infuriates me that, after more than sixty years since our government voted to introduce metric units into United Kingdom life, we are in such a muddle over measurement. So, please permit me to throw my baseball cap into the ring.

May I, to start, challenge a few of Charlotte’s statements? First, I contend that at no time did the French force us to adopt the decimal system. In fact, after the Revolution of 1789 the French government tried to decimalise everything, from a ten-day week to a ten-month year. You don’t need me to tell you that that plan didn’t survive.

Time, ladies and gentlemen, please!

Second, it is far more likely that the Babylonians, with their love of 60, not the Egyptians (who used base 12), who are responsible for our measurement of time using base 60. After all, they deduced that they could divide up the year into 360 days. This led to dividing the circle into 360 degrees of angle, as the development of geometry was closely connected with their observations of the skies. Using base 60, we count 60 seconds to a minute, and 60 minutes to the hour.

The 24-hour clock comes from the Egyptians who used sundials and measurements of shadow. Not being in temperate latitudes (where daylight hours vary greatly by season) they could organize their daylight day into 10 hours plus 2 for twilight.

The circuit of the Moon around the Earth takes approximately 28 days, which conveniently divides into four to mark the Moon’s phases. Hence a week of seven days.

Litres or quarts?

Returning to the topic of containers, Charlotte quite correctly stated that most of the liquids that we buy come in sensible metric amounts. For instance, most soft drinks are sold in litres or a fraction (e.g. 750 ml) or a multiple (e.g. 2 l).

But, thanks to the wording of the metrication advice given by the government when the process of metrication started in the 1960s, certain substances, notably milk and beer, should continue to be supplied in their traditional, or a conveniently close measure. Hence the reason that most of us buy our milk by the pint or multiples of a pint. But not all. And we shall return to that anon.

Meanwhile, although other dairy products were for a while presented in their historical measures – a pint, or a half pint – it is quite a long time since cream began to be sold in tubs containing a multiple of 150 ml. Probably the most popular,being the nearest to a half pint, or 10 fluid ounces (fl. oz) is 300 ml, the equivalent of 10.558 512 fl oz. Just over half a fl. oz more. However, St Ivel™ continues to sell their buttermilk in tubs of 284 ml. This, of course, is the definition of half a pint.

By the by, when Charlotte and I were schoolchildren, we received a daily bottle (yes, glass bottle) of milk at school. The bottle was ⅓ pint. Today, if you’re willing to pay for it beyond Year 2, your child can still enjoy a small carton of full-cream pasteurized milk. The carton is still ⅓ pint, but defined in millilitres.

I wrote a few lines earlier that we don’t all buy our milk in multiples of a pint. I went shopping recently for some milk, and examined the shelves. The choice is suffocating! My preference is for a brand of organic milk from Somerset. It comes in litre and 2-litre containers. Alongside it is the supermarket’s own brand, in containers that are multiples of 1 pint.

And here’s another gripe that I have. In her article, Charlotte reminded us of the different units which we used in our Imperial youth. But the supermarket seems to have forgotten this, and labels are all in pints.

— What do you mean, 2 pints? Isn’t that a quart? What’s 4 pints if it isn’t half a gallon? And where on earth did 6 pints come from? You mean ¾ gallon, don’t you?

Ah! But what’s this? It’s the supermarket’s own brand of filtered milk. In a 2-litre jug. I suspect that the choice of the (slightly) smaller jug than the one used for the standard pasteurised, homogenised milk, is to shave a couple of pence off the sale price!

The nurse will weigh you now, ma’am

Charlotte mentioned us being weighed in stones. Well, first, our bathroom scales are set to kilograms, and I have scarcely any idea what my weight is in stones and pounds. Second, and far more important, the doctor or practice nurse will also weigh us in kilograms. What they then tell us is another matter entirely.

We still have a tendency to talk about a baby’s birth weight in pounds. The truth is that the maternity unit weighs and registers the baby’s weight in kilos. Then they look it up on a table and tell the parents the equivalent in “old money”. And they don’t always read the table correctly, as I know from personal experience.

Talking of ‘old money’

Charlotte referred to our tendency to prefer to count in dozens. It’s true that a duodecimal system has some advantages. Notably twelve does divide conveniently by 2, 3, 4 and 6. Before decimalisation, we counted twelve pennies to the shilling. People who still use feet and inches know that there are twelve inches to the foot. But measuring length is another can of worms, and deserves an article all of its own.

And don’t get me started on the roads!

Why change?

To start with, change is nothing new. A single system of weights and measures was demanded by Magna Carta, since there wasn’t an agreed measure for anything across the kingdom. Adoption of the metric system and a decimalised coinage were called for during the reign of Queen Victoria.

In fact, parliament did succeed in partially decimalising the currency with the issuing of the florin (“One tenth of a pound”) in 1849, and the double-florin in 1887 at the time of Queen Victoria’s Golden Jubilee. The florin survives to this day, in the guise of the ten-penny piece. The double-florin was abandoned,having earned the nickname of ‘barmaid’s grief’, by virtue of the frequent confusion of the double-florin (4/–) for a crown (5/–) and consequent errors in giving change. In time the crown fell out of use, but the double-florin rose like a phœnix in the (slightly odd) shape of the 20p piece.

Global Britain

In actual fact, the move to change came from trade and industry. The rest of the world, with few exceptions, had adopted the metric system, and most of the Commonwealth were resolved to make the change, if they hadn’t already. It was the desire to be able to continue to trade with the rest of the world which was the impetus.

It had nothing to do with joining the ‘Common Market’ which happened eight years later, and it was supposed to be complete within ten years. The change of government in 1970 threw a spanner in the works, and we’re still dragging our feet. Literally!

References

This article first appeared in Kent and Surrey Bylines in 2023.
https://kentandsurreybylines.co.uk/wellbeing/education/more-metric-mystery/

https://kentandsurreybylines.co.uk/society/food-drink/millilitres-or-fluid-ounces/