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A PHYSICIST WRITES . . .
I bring you news from the South of France, where Mrs S and I are visiting my sister and brother-in-law. We are only a few miles from the foothills of the Pyrenees, and the mountain-tops are redecorated with snow every time it rains on us down below, which is some compensation. The papers announced today (1 May) that rain fell in this region on 28 out of the 30 days of April. However, I can report also that it was today we heard the first cuckoo of spring.
Our hosts, being now resident in France, have been advised by friends that if they happen to be stopped in their car by a gendarme, he (or she) is quite likely to tell them that they are obliged to exchange their UK driving licences for permis de conduire, but this is incorrect – until such time as one commits une infraction punissable against le code de la route. So they are obliged instead to keep a copy of the relevant licences regulation in the car, for showing to any such misinformed officer.
Incidentally, it’s curious (and potentially confusing?) that les codes means not only codes, as in Highway etc, but also dipped headlights. Though I believe the more common term for these is feux de croisement : fires at a crossroads, I suppose. Whereas headlights on full beam are feux de route, or else pleins phares, which at least is a straight translation from English. But that’s probably enough light shed on this little corner of the French language...
From July, all drivers in France will be required to carry an approved single-use breathalyser kit in the vehicle, so that they can check they are safe to drive and not in a state of ébriété (this word is another curiosity: did the French decide to drop the prefix “in-”, or did we decide to add it?). You may regard the new regulation as good, or alternatively, bad news. The bad – or good – news is that it won’t be enforced until November! And even then the fine for having mislaid or already used your kit will be only 11 euros.
OK, surely any measure that raises awareness of the dangers of drink-driving is a good thing, and within France these éthylotests will be available for just a euro or two. But do you believe that’s what they will be sold for on the ferries, as you cross from the UK? And then is it likely that drivers will actually want to put themselves to the test after they’ve had a drink? Especially if doing so will leave them without the working breathalyser needed for satisfying a gendarme.
The answer to this last difficulty is of course to keep more than one kit on board – advice that has been issued widely (in both English and French). But here’s a strange thing: I’ve never seen a similar recommendation made regarding the carrying of spare specs in countries where this is mandatory (that’s if you require lenses at all for driving). Only in my columns, I think, will you have read the warning that one spare pair is not enough, for if you suddenly need to wear them (having damaged your regular specs), you will be breaking the law!
There is suspicion here in France that the regulations requiring first hi-viz vests (one for each occupant) and now a breathalyser to be carried in every vehicle were brought in as a result of lobbying by the manufacturers of these respective items. If this is so, you wonder what will be next: compulsory gloves, blankets and headgear in case you’re stranded in cold weather? Supplies of food and drink? Tent and sleeping-bags for when the car is stuck where it’s too risky for you to stay in it overnight? These are useful things to have with you, maybe, but if a nanny state is eventually going to be made to dictate that drivers load them all in, there will be no space left for passengers.
The Pyrenees are lightly festooned with cables for conveying either electricity or people (in gondolas etc). Seeing some strung across a deep valley, I began to wonder how they are erected. It turns out that several methods have been used (world-wide, I mean) including kites, rockets, helicopters, and brute-force hauling across the valley. Nearly always, though, a light-weight line is set up first and used to draw heavier cables across, until the full-size one is in place.
What is hard to appreciate is the amount of tension all along such a cable (assuming that it’s only sagging slightly): because the direction of the tension at each end is nearly horizontal, only a small fraction or ‘component’ of it is available to do the job of vertical lifting. Or to put it the other way, the tension has to be many times the total weight of the cable. And if the latter is also supporting a gondola, the additional tension is similarly going to be very much more than the weight of the gondola (and anyone in it). But don’t worry: there is always a large safety factor built in to the design! Or so I’m told.
Gazing at valleys and mountains reminds me that although this [Thames Valley Group] newsletter included last month a list of fuel-saving tips from the IAM, such lists never seem to include advice to avoid hills. In my September 2006 column I estimated that even driving up a gradient as gradual as 1 in 10 can quadruple the rate of fuel consumption. Sometime I will try to refine my calculations, but meanwhile I would recommend that you consider going around any hill rather than over the top. Within reason, of course. There’s no easy fuel-saving way round the Pyrenees, for example, though you may be lucky and find yourself near a tunnel that goes through them.
Lastly, returning to the piano-marathon that I mentioned two months ago (I played through all 32 Beethoven sonatas, to raise money for hospital equipment: see www.justgiving.com/beethoven32), I can’t resist passing on a comment made by the editor of a quite different newsletter, who came to listen and later printed a photo of me at the keyboard: “Readers will note that he is only using the accelerator pedal!”
Perhaps I should explain that Steinways and similar pianos have three pedals. The ‘sustaining’ one on the right was indeed all I needed for driving this grand instrument: so responsive was it that I never had to depress the clutch, I mean the ‘soft’ pedal. As for the brake – sorry, ‘sostenuto’ – pedal in the middle, to operate this effectively you really need to be an advanced piano-driver.
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