"We were all on this ship in the Sixties, our generation," John Lennon remembered later, "a ship going to discover the New World." This carefully mythologised wild ride, suggests Ian McEwan's new novel, was slow in departing. In On Chesil Beach, the summer of 1962 is fenced round with remnants of the past. The "old buffer" Harold Macmillan is running the country; concert halls are filled by "the last of the Victorians"; and hotel bars by chuntering Second World War veterans. But this is also a time when "youthful energies were pushing to escape like steam under pressure". The old order, at least some people hope, is about to give way to a New World of CND rallies, music and, of course, sex.
On Chesil Beach traces this longed-for tran-sition from innocence to experience between a newly married couple, Edward Mayhew and Florence Ponting. Born in 1940, the same year as Lennon, they are "young, educated, both virgins", and firmly mired in pre-"Love Me Do" proprieties. McEwan's chamber tragedy unfolds from their disastrously out-of-step expectations of their wedding night. Edward, an aspiring historian and blues aficionado, dreams of lascivious conjugal excess; Florence, an Alice-band-wearing violinist, does not.
It's a simple premise, for a slight, 166-page book. After the baroque improbabilities of Saturday, On Chesil Beach is fiercely restrained. Metaphors are reined in - the suggestiveness of the dead-end shingle spit "between the sea and the lagoon" is downplayed - and any hint of sensation is ruthlessly pruned back. A delicate web of allusions suggests that Florence's aversion to her husband's embraces may stem from a series of childhood trips with her father. To the Cement Garden-era McEwan, this would have been fuel for a novel in itself; here, it provides no more than a background hum of disquiet.
Even his characters' political convictions are leached of any particular significance. McEwan was sufficiently exercised by a Guardian review claiming the anti-nuclear, pro-Soviet young couple were portrayed as "hopeless naïfs" to write a letter bemoaning the "prevailing atmosphere of empowering consumerism" that saw characters falsely identified with their "novelist creator". Accused of everything from chest-beating neoconservatism to political apathy for Saturday's bizarre account of the Iraq war debate, McEwan is determined, here, not to "say" anything at all.
Appropriately, On Chesil Beach depends on the unspoken. "They lived in a time when a conversation about sexual difficulties was plainly impossible," runs its opening fairy-tale-like sentence, heralding a fruitless search for the magic words that would make such a conversation possible. On Chesil Beach is a linguistic balancing act, each sentence delicately positioning itself both by historical co-ordinates - an early-Sixties world of Austin 35s and wireless news bulletins - and by more private reference points - the separate anxieties and assumptions of the young bride and groom.
McEwan, as Atonement demonstrated, is at his best with this finely tuned historical pastiche. The period detail allows him some virtuosic touches: he almost has fun with Edward's bemused first encounters with "muesli, olives, fresh black pepper, bread without butter, anchovies, undercooked lamb, cheese that was not cheddar, ratatouille, saucisson, bouillabaisse, entire meals without potatoes".
But Edward's sexual initiation does not keep pace with his culinary education. His private sexual vocabulary, like that of his new wife, is rife with critical gaps. He is incredulous that "the most sensitive portion of himself would reside, however briefly, within a naturally formed cavity inside this cheerful, pretty, formidably intelligent woman", and is consumed with a fear of "arriving too soon". Florence, meanwhile, is repulsed by "the idea of being touched 'down there' by someone else". She has been dutifully reading a marriage manual, and the terrifyingly foreign terms it provides are tweezered-out with squeamish italics: "mucous membrane" and "the sinister and glistening glans".
Their encounter on the hotel's narrow double bed is predictably disastrous. Lacking a common language for their anxieties, Edward and Florence proceed in a cloud of nervous conjecture and comically misplaced certainty ("She was desperate for him to take the lead," Edward manfully assures himself) that ends in a final, irrevocable separation.
But despite appearances, On Chesil Beach is no tragi-comedy of period sexual manners. The misunderstandings stem less from the fact that the "language of therapy was not yet in general circulation" than from the writerly preoccupation outlined in Atonement: the difficulty of believing, and conveying, "the simple truth that other people are as real as you", the "peculiar unshared flavour" of an individual existence. McEwan's forensic account of the warring couple's partialities - Edward longs for "a stern impartial judge who understood his case complete ly" - is perfectly constructed, but fails to throw off the feel of a private technical exercise. In a novel so reliant on bias and conviction, a little more authorly engagement would be welcome.