JUST for a moment, ignore the frocks . . . even the model Dovima in a ballgown for an infanta, grander than which garb cannot get, designed by Cristobal Balenciaga and photographed by Richard Avedon . . . and take a magnifying glass to the panorama of Christian Dior's Paris salon in 1951.

Two bustled models rustle across the carpet, encircled by a double-rank of hard chairs.

About 30 women and 15 men are seated. They're not a pretty sight. The men look like aged industrialists, and charmless with it. There's some serious jewellery on a couple of the women, and the hats like befeathered pancakes that have landed on the pates of the rest must then have been chic; but otherwise the dames resemble an assembly of headmistresses.

They're a lot harder than the chairs. They're all here to judge, with extreme severity. I'm guessing, given the specs and notebooks, that this was the first showing, for the press, or the second, for the American trade buyers, although they would all have had to wait thereafter: buyers, three weeks for their purchases, which they would resell or copy legally; the press, 30 days before they could publish photographs and sketches.

Welcome to the remote world of couture in Paris, and London, from its post-war rebirth with Dior's 1947 collection to his early death a decade later, as displayed in the autumn's London V&A exhibition and this accompanying book. Although that 1947 collection was celebrated as the New Look, in fact it was an old look, a deliberate revival of the French craft skills of Dior's belle epoque childhood as the best way to challenge the wartime ascendancy of the American glamour which had developed from the US's industrialised sportswear industry.

Yet, at the same time that Dior proposed to his many private clients some 300 outfits a collection . . . many of them neocrinolines 10 metres round the hem supported by an undercarriage of linings and dependent from a waist waspie'd tight (everything women had fled from after the first World War, let alone the second), he set up a prototype business in New York to sell luxurious almost-ready-to-wear. His real money came from licensing and franchising deals, and perfumes.

Dior, the sly owl who was master of spectacle, is the hero of this book, although his reticent rival Balenciaga is properly admired. They were both sculptors in cloth; they and their confreres, Jacques Fath, Jean Desses and Pierre Balmain, projected women as fabulous, unattainable objects within voluminous carapaces. Because of the photographic emphasis of the book, and the exhibition, on the most gorgeous of those shells . . . the full evening dresses . . . this world seems far further gone into the sartorial past than does the inter-war era when Elsa Schiaparelli knitted cracking jokes and wore them as sweaters.

It's all so cold, and not just because of the strapless bodices: the model Dorian Leigh, bone structure elevated to the point of parody, posed by Avedon in a Piguet gown, connects through her hauteur with those disapproving press beldames in that Dior salon. Rejection, disdain and exclusion were the norms: fun, eh?

The customers were usually rabid, avid socialites, described by Balmain's directrice, Ginette Spanier, as haggling over prices like fishwives while maintaining a public facade of utter glaciation.

Presumably, they included those duchesses, baronesses and Onassis wives from whom Cecil Beaton solicited rails of exhibits for the V&A's collection; the book's essay by Hugo Vickers on Beaton scrounging from the wardrobes of the well-born is chilled with such snobbery, it gave me freezer burns. A glaze of frost on every page.

There a informative entries if you don't mind the overall tone of devout froideur. The section on Mayfair designers, who dwindled almost to extinction by 1957, pays overdue respect to the tailored suits of Digby Morton and Charles Creed; these, like Balenciaga's seamed tweeds, were bespoke real clothes . . . they would certainly give that feeling of inward tranquility which religion is powerless to bestow. I want to wear them, likewise the garments in a 1949 sketch of holiday ensembles from minor names, prescient as well as delicious . . . capri pants, Pucci pyjamas and near-beatwear, some in a short-lived synthetic called cracknyl.

There's a too-brief tribute to photographer Erwin Blumenfeld's Vogue covers of lipsticked mouths, the crop of the pics calibrated to a micrometre; an original chapter on the symbiosis between couturiers and their textile suppliers; and patient research into the traditional Parisian labour hierarchy (although the V&A's reprint of Dior's autobiography offers a far better understanding of the technicalities of couture).

There are omissions: the return of Gabrielle Chanel to couture in 1954, as the anti-Dior ("elegance in clothes means freedom to move freely", she snarled about 17Christian's immobilised, constricted feminine divinities) gets a one-line mention and no images, as if the compilers of the book and exhibition were scared of her. As they should be. I like to imagine her slouching through the show, ciggie in the corner of her mouth, mocking the marquee dimensions of the opera coats.

She was a generation, nearly two, older than Dior and Balenciaga, and yet the immediately post-1957 future belonged to her and her easy Linton Tweeds.

And after that? The most beautiful female in these pages isn't Barbara Goalen, or Eugenia Niarchos, or even Audrey Hepburn, gussied up and with poodles, but a girl snapped at work on transparent stuff in Dior's atelier flou (light dressmaking) . . . a deuxieme-main debutante, or second hand, one needle up from gofer. She's wearing a cheap printed dress, cotton or rayon, as are her lovely mates in a nearby group shot. Her face is alive with enthusiasm.

She'd look a laugh if she were stuck inside the archaic ensembles on the pages round her.

Up in the salons, they were were conjuring up yesterday with six daily changes of outfit, cocktail dresses, mink stoles, and always, always, those elbowlength gloves. Down in the workrooms, the fashion for being young was waiting to happen.