Radio: So Boyle's new baby has five little fingers

ST PATRICK, whose feast was last Tuesday, used the trefoil shamrock as a metaphor for the Trinity, three persons in one God. Perhaps BBC Radio, with its five distinct branches, should adopt a hand for its symbol: R1 could be the frivolous little finger; R2 the sentimental one, bearing rings; R3 the long, arty one, slightly out on a limb; R5 the thumb, hitching a lift and riding ad hoc on the news, and R4 the index finger - admonishing, insisting, pointing the way.

Forgive the whimsy: it has been a week of redefinition at Broadcasting House. Radios Two and Four have both launched new schedules: in their advertising they appeared tricked out in new springtime logos. But their "liveries" do not - in any sense - suggest digital radio. R2 has a neocubist jumble of little coloured squares on a background of bright blue (Terry Wogan speculates that it is the colour of their "various" veins). R4 has some quaint, old-fashioned light bulbs masquerading as quotation marks, goodness knows why.

So what do they promise us? Well, Jim Moir, the R2 Controller, is a jovial, witty man whose policy is one of slow evolution. Cleverly, he has let it be believed that his station is getting younger and livelier: this is largely based on the fact that Jools Holland and, after him, Mark Lamarr will be devoting an hour a week to rock'n'roll.

Yet his other new signings are less youthful, and exclusively male - people like Joe Brown and the Alans Whicker and Freeman. And R2's new daytime schedule is scarcely innovative. In the wake of Debbie Thrower's imminent, regrettable departure, Ken Bruce and Ed Stewart will stretch their shows to fill the gap. They are both likeable, but this means that there will be no woman presenter all day after Sarah Kennedy clocks off at 7.30am.

And the evening specialist programmes retain their sacred status. At 8pm every Tuesday, you may still steal a mesmerising glimpse at the arcane pleasures of the keyboard anorak, as The Organist Entertains (if you've never tried it, please do: it's one of the wonders of the broadcasting world). R2 wears its eternity ring with pride.

The R4 launch made a bigger splash. Virtually everything - even the shipping forecast - is being shifted at once, and will doubtless cause ripples for months. The rationale behind the changes is logical and sensible, based on reliable times for drama, discussion, readings and so on, and the basic ingredients of Four are unlikely to change substantially. A few decisions seem retrograde or harsh. Yet in a year or two we'll probably have forgotten that Woman's Hour once had regional days, that On This Day provided unrivalled oral history, or that children ever had programmes of their own.

Some ideas are welcome: it seems reasonable to make Yesterday in Parliament a long-wave option, for example. But there may well be problems: The Archers and Today are both being given more time because they are so popular, yet it may become apparent that they can be stretched no further without weakening. Time will tell, and so, vociferously, will Feedback. Meanwhile, the new schedule looks, dare I say it, promising.

In the last days of the old dispensations, four programmes typify the best of these two stations. Tom Wolfe is writing another enormous novel at the moment, set in the American southern states. He made a false start but decided to turn it to his advantage and "publish" it as an aural novella. So last week and next, the Late Book is Ambush at Fort Bragg (R4). It tells of Irv Durtscher, a New York TV producer working on a hugely popular news programme, who bugs a topless bar in North Carolina in the hope of catching some murderers. The suspects are soldiers, their crime the murder of a gay colleague.

With the help of hidden cameras and the obvious, "pneumatic" charms of one Lola Thong, the soldiers are trapped. But they prove to be heroes, scarred veterans of a violent battle in Somalia; and Irv is forced to reconsider the morality of the whole affair. The tale is magnificently read by Frank Muller and written with an eye on episodic reading. Insidiously, the complicated story is summarised at the beginning of each episode - you could start tomorrow and still grasp it - or you could buy it on cassette: it will never be a book.

Noah Richler's The Face (R4) opens with a mortician's mordant views on the fragility of beauty. It was originally scheduled for last August, but in the ultra-sensitive atmosphere following the death of the Princess of Wales, it was deemed too shocking for airing and postponed. Peter White, the blind presenter of In Touch, which is retained under the new schedules, has never seen a face. He asked artists and academics, politicians and policemen to describe what is to him just a physical structure. Their answers were packed full of revealing moments - and superb.

R2 broadcast the latest in its series of concert performances of musicals. Lerner and Loewe's Camelot, "where the tables are round and the relationships triangular", is a peculiar hybrid. "Lancelot" and "Guinevere" as doomed lovers have some dignity: in the script they were Lance and Ginny, names which belong in a Cortina behind fluffy dice. Ginny has lines like "Nonsense, dear" and "Can you stay for lunch?" Paul Nicholas was a curiously American, uncomfortable King Arthur; and Jason Donovan as the wicked Mordred was frankly hilarious - and yet ... In spite of the pantomime Gilbertian songs and the corny jokes, Helen Hobson's perfect delivery and clear, soaring voice redeemed it and kept me with it to the bitter end. And I really fancied trying Morgan le Fay's lifestyle: passionate afternoons, gluttonous nights, and slovenly mornings.

Finally, there was a very funny new pilot comedy, which could easily become a hit series. Cleverly written by Bill Dare, The-Big-Town All-Stars (R2) starred Stephen Tompkinson and Doon Mackichan as members of an a capella group who are trying to make the big time but not yet ready to give up their day jobs - they are part-time dentists and geography teachers. That doesn't sound funny, does it? Sorry. All I can say is that I had to stop the car to laugh.