Over recent days, as television news has covered the terrible floods, I am reminded yet again of one of the odder misfortunes inflicted on Britain in our lifetime.

An Environment Agency official tells us a river has burst its banks having risen ‘5.2 metres’, only for a traumatised local to tell us it is ‘17 ft higher than normal’.

Meanwhile, a hapless BBC reporter interviewing a flood victim solemnly informs us the water is ‘300 mm deep’.

Metric: Environment Secretary Liz Truss - pictured at the scene of a collapsed bridge in Tadcaster, North Yorkshire, last week - said that water levels on the River Aire were ‘a metre higher’ than they have ever been

Not to be left out, Environment Secretary Liz Truss yesterday told the Commons that water levels on the River Aire were ‘a metre higher’ than they have ever been.

Only when a beleaguered homeowner tells us ‘it’s a foot deep in the living room’ do most know what they are talking about.

The fact is that we have two quite different systems of weights and measures — one invariably used by government officials and the BBC; the other still used by millions of people because, for most everyday purposes, it seems much more sensible and easily comprehensible.

The reason we live in these two different worlds — imperial and metric — can be traced back 50 years to one of the murkiest episodes in the history of our parliamentary democracy.

It centres on the scandal of how politicians robbed us of our old system of weights and measures — feet and inches, pounds and ounces — to replace it with what they claimed was the ‘much more sensible’ metric system.

I am not concerned initially with the respective merits of the two systems — although I shall touch on those later — but with the peculiarly dishonest tactics devised to bring about an enormous change in Britain’s way of life without consulting voters.

Start of the story: Harold Wilson’s Labour government used a Written Answer buried at the back of Hansard in 1965 to announce its intention to replace the weights and measures used since the Roman Empire

Fully aware of the highly controversial nature of the new system, they sought instead to impose it by stealth, deception and downright lies.

Kept under wraps: Prime Minister Edward Heath learned in In 1972 that Brussels planned a directive to ensure that all member countries must use metric

The story begins in 1965 when Harold Wilson’s Labour government used a Written Answer buried at the back of Hansard to announce its intention to replace the weights and measures used since the Roman Empire.

The first lie was a pretence that the switch to metric was in response to the wishes of British ‘industry’. Years later, after I unearthed the relevant documents, it turned out ‘industry’ had requested nothing of the kind.

It is true that, under pressure from bureaucrats, the chief trade body representing businesses had expressed interest in the possibility of such a change since it would affect its members, but it merely said that many were ‘concerned’ by its implications.

In 1968 came the second lie when the then Technology Minister, Tony Benn, let slip to MPs his wish to see Britain ‘fully metric’ by 1975.

This change would be entirely voluntary. ‘Compulsion’, he twice promised, ‘is not part of the process’ (hence, no need for parliamentary debate).

However, within months, the Government issued a statutory diktat making it a criminal offence for shops such as chemists to sell drugs in anything but metric measurements.

In 1969, a Metrication Board was duly set up to ‘co-ordinate the process’. It ruled that it would be illegal to teach any other measuring system than metric in schools.

I first exposed this subterfuge in a magazine during the 1970 election campaign, and a reader badgered her would-be Tory MP into promising that Parliament would debate the subject. It proved to be only a short debate and Tory backbenchers were furious that such a huge change to British life was being smuggled in.

New measurements: In the fabric department of Selfridges in 1975, assistant Vanessa Holm begins her first day using metres and centimetres following the metrication of length and breadth

In 1972, when Prime Minister Edward Heath was taking Britain into the European Common Market, he learned that Brussels planned a directive to ensure that all member countries must use the metric system. Not surprisingly, he insisted that this be kept under wraps until Britain was safely in.

Minister responsible: Michael Heseltine claimed the measures had ‘nothing to do with Europe’ but had been British policy ‘since the Sixties’

Next, Heath issued a Metrication White Paper based on the fictitious claim that Britain was only adopting the metric system in response to ‘two polls’ of industry. In truth, no polls had taken place.

Five years later, the Tories — by then led by Margaret Thatcher — rebelled and, in 1980, she scrapped the Metrication Board. Brussels swiftly retaliated and issued a directive requiring all members of the ‘European Community’ to use the metric system. (All except Britain and Ireland already did).

Five years on, the Thatcher Government parried this with a new Weights and Measures Act, confirming that the ‘imperial’ system would still be legal.

In response, Brussels issued a directive in 1989 designed to bring Britain into line — though it still allowed us to continue, for a time, using miles on road signs and pints (but only for beer, cider and milk).

It was this directive that led Thatcher’s successor government led by John Major to allow it to become a criminal offence to sell goods of any kind, including fruit and veg, except in metric.

Disingenuously, the minister responsible, Michael Heseltine, claimed the measures had ‘nothing to do with Europe’ but had been British policy ‘since the Sixties’. But the documents he signed were the result of the European Communities Act — which was passed in 1972.

And so the juggernaut of an unpopular metric system was crushing our imperial traditions.

Opposition came to a head in 2000, when a Sunderland stallholder, Steve Thoburn, was charged with the criminal offence of selling a ‘pound of bananas’.

Unpopular system: Opposition came to a head in 2000, when a Sunderland stallholder, Steve Thoburn (pictured), was charged with the criminal offence of selling a ‘pound of bananas’

With four other so-called ‘Metric Martyrs’, they went to the Court of Appeal and argued that under the ancient rule that no Act of Parliament can be overruled by one passed previously, the 1985 Weights And Measures Act could not be negated by an edict issued under the European Communities Act of 1972.

America landed a man on the moon using miles, feet and inches, and thrives using the imperial system

However, Lord Justice Laws ruled that the European Communities Act was a ‘constitutional statute’ — so important that it could not be overturned by law which came after it.

Many larger businesses, such as those making tinned foods, welcomed the new laws as they could cut their old ‘1 lb’ tins (454g) to 400g and charge the same price, hoping customers would not notice. Confectionery manufacturers followed suit.

Despite the anti-democratic imposition of the metric system, shopkeepers were still allowed to print the imperial measurement next to the metric equivalent.

But in 2002, Brussels issued a new directive designed to make this illegal, and again the Government supinely complied.

It thus became a crime for retailers to make any mention of the old weights and measures.

Loophole: Peter Halstead and Irene O'Brien of the Gemini Fish Suppliers in Codicote, Hertfordshire, said in 2004 that they had avoided the metrication laws by running the shop as a club costing one pence to join

At this point, there was a welcome intervention by Americans — who still use imperial measurements — after they were told by the British Weights and Measures Association that giant U.S. corporations would be breaking the law if they sold any products in the EU without measurements in metric. Thus it would have been illegal to refer only to a 42in TV screen.

The U.S. firms were worried about the vast costs involved and Brussels at last backed down.

Imperial: When we are told the weight of a new-born royal baby, such as Princess Charlotte, it’s 8 lb 3oz — rather than an alien 3.71 kg

Deeply embarrassed, the EU trade commissioner stated that ‘imperial measures’, such as the mile and the pint, were ‘the very essence of the Britishness that Europeans know and love’. The British could use imperial equivalents alongside metric measures for as long as they wished.

With this last fudge, 40 years of deceit and chicanery more or less came to an end.

Never again would a greengrocer be criminalised for shouting, ‘Lovely toms, a quid a pound!’ at customers who hadn’t a clue what ‘half a kilo’ was.

Supporters of metric still insist theirs is a much more ‘rational’ system. But they overlook the fact that America landed a man on the moon using miles, feet and inches, and thrives using the imperial system.

In truth, the only way metric is more user-friendly is simply that it divides and multiplies by ten. But for everyday uses, such as cooking or carpentry or measuring a carpet, I would argue that imperial wins every time.

When we are told the weight of a new-born royal baby, such as Princess Charlotte, it’s 8 lb 3oz — rather than an alien 3.71 kg.