A GERMAN, a Spaniard and a Frenchman walk into a pub….and probably get rather confused. The friends, visiting Britain for the first time, all fancy a lager and the barman asks them if they want a pint or a half. But they have only just been in a supermarket next door where they bought a half litre bottle of milk.

They want a burger and chips, and scour the pub menu to find that it proudly offers ‘quarter pounders.’ But when they had earlier bought some mince at the shop, it came in a half kilogram pack.

Meanwhile, the Spaniard is looking forward to visiting his niece and seeing her newborn baby. He’s been told the girl 'weighed in at 10lbs,13ozs' at birth but doesn't realise this means it's one very big baby.

The pals have hired a car and just filled up with 40 litres of petrol at a local garage, and so they are bemused when they hear a customer in the pub’s lounge bar loudly and proudly telling the landlord he's bought a new car which does '50 miles to the gallon.' They search online and find that petrol hasn't been sold by the gallon for more than 30 years.

Welcome to Metrimperial Britain – the country where people can hop in one sentence from metric measurements to imperial and then back to metric again without taking breath. Where road signs give motorists distances in miles and yards, but where other signs warning of low bridges – such as the one pictured at the entrance to the tunnel near the National Railway Museum in Leeman Road -give the height of the tunnel in metres as well as feet and inches.

The country where one liquid is measured in litres and another in pints, where shops sell curtain or dress material by the metre, and fruit and vegetables by the kilogram but where most people think of their height in feet and inches, and their weight in pounds and ounces.

So how did we end up here in this strange half-way house between Imperial and Metric measurements – and does it really matter?

Well, metrication in the UK – the process of replacing Imperial units with metric measurements – has been talked about for a very long time. It was discussed in Parliament as long ago as 1818 and a Select Committee recommended in 1897 that it should become compulsory.

But it wasn’t until 50 years ago, in 1969, that the ‘Metrication Board’ was created to coordinate and promote the shift to metric measurements. There was subsequently a brief move to make metrication mandatory but this was reversed after resistance and the Metrication Board was then abolished.

Since then, we’ve drifted very gradually in a metric direction. I remember buying gallons of petrol when I first learnt to drive in the 1970s but garages switched to selling it by the litre in 1984.

However, I still look at a car’s mpg when trying to assess how economical it is in its consumption of fuel. Food had to be sold by the kilo from 2000 but I went into a market recently and heard a stallholder hollering: “Pound of bananas.”

It’s all slightly bonkers and confusing, so maybe it is time for us to finally launch a metric revolution, and do away with those pesky miles, yards, feet, inches, stones, pounds, ounces, pints and gallons.

But then again, maybe this very British quirkiness has a certain eccentric charm about it.

And I guess what matters most is that we understand what a measurement means. Give it another half century and we may finally get fully to grips with metrication.

I recently spotted a reader's letter to a national newspaper complaining about its description of the height and weight of an English rugby player, Maro Itoje: “Please use imperial units when describing rugby squads. To describe Maro Itoje as 1.95m and 115 kg is meaningless; say he’s 6ft, 5in and more than 18st and one knows what one’s dealing with.”

I’ll drink to that, but maybe with a pint rather than 0.568262 litres.