Some months ago, a shopkeeper was being prosecuted for not going metric, at the same time a licensee in Scotland was being threatened with prosecution for selling beer in
half-litres.
Yes, it's true. You don't even have a choice in this country. Although most other goods have to be sold in metric measures of some kind, beer and cider must not be sold on draught in metric measures. In bottles, yes. But not when it comes to pouring a pint.
The other drinks behind the bar have gone metric. First it was spirits - not all of them, mind you - just gin rum, vodka and whisky. Those four used to be served in what we called a "six out", one-sixth of a gill, or one-fifth if you were in the north of England and even one-quarter if you enjoyed Scottish hospitality.
Now, it's 25ml, or 35ml in more generous areas. This applies to all measures used for these spirits, and it must be the same throughout the premises - you can't mix the two measures. But here's another irony; you are not obliged to serve other spirits, such as brandy or liqueurs, in those measures at all. You could still use the old measures and not be prosecuted, unless you advertised them on your price list or menu.
It's the same with wine. After a great deal of lobbying by certain people, for reasons which were not always obvious, the trade was faced with two quantities for "wine by the glass" - 125ml and 175ml. Although you are not obliged to use lined glasses behind the bar, you must have an accurate way of measuring wine if you serve it in this way. But it must be metric.
Selling a bottle of wine, which has the quantity on the label, is not a problem. But selling by carafe can be. Again, the measures you allowed are all metric, they must be accurate and specific - 25cl, 50cl, 75cl and one litre - and there must be a menu or notice giving the quantities in use.
So why didn't the Great British pint go metric? Well, they tried, but there was so much resistance that it was considered right for an exception to be made - for milk and beer. But while milk is always sold in dual-marked packaging, draught beer has the unique distinction of being ring-fenced against the encroachment of this fiendish measurement from Continental Europe.
Trading Standards Officers, who enforce this law, say it could cause confusion with the public, not knowing whether the "pint" they were getting was 568ml or a half litre (500ml). Given that most bottled beers in supermarkets are now in the latter quantity, it seems fairly obvious to me.