‘Why are you going?’ I was genuinely curious.

He thought for a moment. ‘Because I can,’ he said.

The history of costume is, as we know, a fascinating subject in itself and I find it interesting that I will almost certainly live to see the death of one outfit, at least, that was significant enough in its heyday, namely White Tie. From early in the nineteenth century, thanks to Mr Brummell, until the middle of the twentieth, it was the male costume of choice for any Society evening, the club colours of the British aristocracy. When, in the late 1920s, the Duke of Rutland was asked by his brother-in-law if he ever wore a dinner jacket he thought for a moment. ‘When I dine alone with the Duchess in her bedroom,’ he replied.

Of course, it was a surprise to some that it survived the war, since six years of dinner jackets and uniforms might have killed it off, but Christian Dior’s revival of an almost Edwardian style of dress, with his bustles and corsets and paddings and linings, had launched a fashion for sumptuous evening clothes that made the short, dull dinner jacket seem quite inadequate as a pair. Then, in the summer of 1950, the Countess of Leicester gave a ball for her daughter, Lady Anne Coke, at Holkham, which was attended by the King and Queen. The following morning yielded two discoveries. The first was a waiter who had fallen into the fountain and drowned, the second that white tie for men was definitely back. Of course, what Dior and so many others failed to understand was that white tie was not just a costume, it was also a way of life, and it was a way of life that was already dead. White tie belonged to the ancient bargain between the aristocrat and those less fortunate that they would spend much of their day in discomfort in order to promote a convincing and reassuring image of power. After all, splendour and glamour had been inextricably linked to power for centuries, until the comparatively recent appearance of Government by the Drab. Before the first war, among the upper classes, five or six changes a day, for walking, shooting, breakfast, lunch, tea and dinner, were de rigueur at any house party and three at least were necessary for a day in London. They observed these tiresome rituals of dress for the simple reason that they knew once they stopped looking like a ruling class they would soon cease to be a ruling class. Our politicians have only just learned what the toffs have known for a thousand years: Appearance is all.

Why, then, did it die so suddenly? Because they stopped believing in themselves. It was not just the loss of the valet that was to prove fatal to the costume; it was a loss of nerve that gripped the Establishment in 1945, and would continue to undermine their confidence until, by the end of the Seventies, for all but a few their role in our National life, and with it the point of their white tie, was gone. My generation saw the last of it. When I was eighteen, all hunt balls were still white tie, as well as all the May balls at Cambridge and the Commem Balls at Oxford. A few coming-out parties still tried for it and one event where it was worn without dispute was Queen Charlotte’s Ball. Now, when, apart from a state banquet at Buckingham Palace or Windsor, or something rich and rare at one of the Inns of Court, it has almost vanished, it seems strange to think that forty years ago we still got enough use out of our tails for it to be worth owning them.

Queen Charlotte’s Ball was not a private party. It was a large-scale charitable event and, as such, did not conform to the normal rules. To start with, it was what was then called a dinner-dance, meaning that we were to eat there and so we would assemble much earlier than usual. Dinner-dances, in those pre-breathaliser days were thought by some to be rather common, I forget now why, perhaps because they had an air of a night out ‘at the club’ in some Imperial outpost, but on this particular evening there was a ceremony to be got through that was considered sufficient to justify it. The plan was to gather at the Daltons’ London flat in Queensgate, to make sure that the group was all present and correct, and then to move on to Grosvenor House almost immediately.

I rang the bell at the Daltons’ front door, the buzzer (for we already had those) admitted me and I knew their flat was on the ground floor, so there was no long climb ahead. The front door must once have been the door into the dining room, when the newly built house had been home to a prosperous late-Victorian family, but by the 1960s that dining room had been carved up into an entrance hall and a medium-sized drawing room. A few good things, as is the wont of such families, had been spared for the flat, in case we might mistake their rank, and what looked like a Lazlo of Lucy’s grandmother, painted as a girl of nineteen, stared down glassily from above the chimneypiece, which, owing to the division of the room, was awkwardly off centre. The oddness of proportion was enhanced by the fashion, then prevalent, for blocking grates with large flat sheets of hardboard, often, as in this case, with an electric fire placed in front. I cannot think of any vogue in my entire life more guaranteed to kill a room stone dead than this blanking of the fireplace, but we all did it. Like the hideous enclosing of banisters on a staircase, which one found in almost every house divided into flats, it was supposed to make the space look modern and streamlined. It failed.

‘There you are.’ Lucy kissed me briskly. ‘Are you dreading it?’ There were four other girls in the room and, counting Lucy, all five were dressed entirely in white, a survival of the custom of wearing white for a girl’s first presentation at Court before the war. It had not, of course, been continued in the last period of Royal Presentation, which had taken the form of garden parties, and the girls would then wear pretty, summer dresses and wide-brimmed hats, but with the end of that and the installation of Queen Charlotte’s as the official start of the Season, the white rule had been revived. They wore long, white gloves, too, but instead of the Prince of Wales feathers that decorate the heads of both mothers and daughters in all those pre-war photographs by Van Dyck or Lenare, this year, at least, white flowers were worn in the hair, tiaras not being considered proper for unmarried girls. Lady Dalton, I was pleased to see, sported rather a good one, which flashed its fire round the room as she walked towards me, smiling pleasantly.

‘You are kind to come,’ she said, holding out her own gloved hand.

‘You’re very kind to ask me.’

‘Lord knows what we’d have done if you’d said no,’ added a bluff, soldier type, whom I took, correctly, to be Sir Marmaduke. ‘Flag down a bus and just collar someone, I suppose.’ One often suspects that a late invitation signifies that a certain scraping of the barrel has gone on. But it is a little depressing to be told it.

‘Pay no attention,’ said his wife firmly and led me away to where the other young stood. The party was more of an age mixture than usual as most of the mothers and fathers of the girls, if not the boys, were to be with us for the evening, so I met a couple of pleasant enough bankers and their wives, together with a rather pretty, Italian woman, Mrs Wakefield, married to Lady Dalton’s cousin, who’d come up from Shropshire to begin the launch of her youngest daughter, Carla. We moved on to the girls themselves. Among them was a plain and russet-faced character, Candida Finch, whom I’d already met. To be honest, I had found her a bit uphill, but we were programmed in those days to make conversation with anybody nearby and so I fell into the small talk demanded of me without much hardship, naming mutual acquaintances, reminding her that we had both been at this drinks party and that one, although we had never spoken more than a few words to each other before now. She nodded and answered, civilly enough but, as always with her, too loudly, too aggressively and, every now and then, with a sudden, stentorian laugh that made you jump out of your skin. Of course, now I can see that she was very angry at what had happened to her life, but one can be so blind and so heartless in youth. I looked at the grown ups sipping their cocktails at the other end of the room.