Here’s a good air travel story, for a change. My wife and I are currently en route for a wedding in Corsica. The bride’s parents are my wife’s oldest friends, Hughes and Caroline. He’s French, she’s English and they live in Nantes. Their eldest daughter Emily, the bride, is Sarah’s god-daughter and she has commanded me to wear a kilt at what is otherwise going to be an overwhelmingly French affair.

When first mooted, the idea of having to wrap myself in several yards of heavy tartan, plus a tweed jacket and waistcoat, in the Mediterranean in April sounded like a recipe for hyperthermia, not to mention a hefty excess baggage charge. But thanks to Sarah’s genius for packing, we’ve managed to avoid the charge and we’re now in Paris, where it’s a mere twelve degrees, and the forecast for Ajaccio, which we reach tomorrow, is no better. So perhaps I’ll be glad of it all, after all.

But there’s more to wearing a kilt than wool. There’s all the other paraphernalia, such as a sporran – mine’s an unusually large russet specimen concocted from the remains of a great-aunt’s mink stole, minus claws and tails; and other items fundamentally inimical to air travel such as kilt pins and every Scotsman’s trusty defender, the sgean dhu, a small ceremonial knife, usually decorated with a cairngorm, an amber-like semi-precious stone, in the hilt. This you stick down the top of your stocking ready for spearing olives, or your neighbour at the wedding breakfast, should they displease you.

Passing through security at Edinburgh airport, the buzzer went off and my small carry-on case was quarantined. I couldn’t think why. Everything suspect was in the large checked-in one. A tall, shaven-headed security man approached and before I could open my mouth he grinned and asked if I had a sgean dhu in the case. Obviously not an uncommon occurrence.

I’d meant to put it in the larger one, but at the last moment, don’t ask me why, had slipped it inside the sporran and put the sporran in the smaller case. Confiscation loomed. Ochone, ochone, as old Highlanders would have cried.

We opened the case, retrieved the offending item and, once he’d unsheathed it and satisfied himself that it really was lethal (believe me, it is), we considered the options. Entrusting it to BAA till our return was one, but that meant going downstairs to lost property, then coming back in through security again. Not enough time.

The security man seemed genuinely eager to help. ‘I know,’ he sympathised, ‘these things are heirlooms. You could post it to yourself. I’m going off in half an hour. I’ll do it for you. Just go to WH Smith and buy an envelope and some stamps. Bring them back here.’ He paused apologetically. ‘I’d better hang onto it for now.’

WH Smith was useless. The only stationery they had was birthday cards. I bought the biggest and a book of four stamps, then returned to security. At the diagonal, the sgean dhu was a centimetre too long.

My friend smiled. Nothing was too much trouble for him. He disappeared to an office and came back empty-handed. He consulted a colleague, then hurried off to a different office and returned with an A5 sized envelope. ‘You’ll need a bit of tape too,’ he said, delving behind a kind of observation stand manned by a rather nonplussed airport policeman and emerging with a roll of Sellotape.

‘There you go,’ he said cheerfully, taking the package. ‘Now you’ll just need to get yourself a bandit knife in Corsica.’ I thanked him profusely, feeling touched by his good nature and willingness to help, and asked his name. It was Graham Bell, he told me. I couldn’t help wondering if his first name was Alexander. His wish to connect and communicate seemed so strong that the association felt quite obvious to me in the moment.

I don’t know whether the sgean dhu will make it back to Birnam. I don’t know what view Royal Mail takes of knives in the mail, or if it even screens for such things. In this day and age I’d be surprised if it didn’t.

But perhaps it doesn’t matter. Walking to our hotel this evening from the Gare Montparnasse, what should we pass on the way but La Maison du Kilt.