Songs Of Innocence, Royal Festival Hall, London

Patti's fire sheds little warmth

Patti Smith's turn as Meltdown Festival director has lured an enviable assembly of artists to the South Bank this month.

Patti Smith's turn as Meltdown Festival director has lured an enviable assembly of artists to the South Bank this month. Tonight's bill is maybe the most casually extraordinary, bringing together mostly female pop icons from Yoko Ono to Sinead O'Connor to perform work "for and about children", in loose tribute to the great London visionary William Blake.

All the vast talent on display over three-and-a-half gradually enervating hours, though, only proves that you can have too much of a good thing. The first minutes are the most engaging and mysterious. Bob Dylan's recorded voice ghosts on to the empty stage, sounding both ancient and fresh as he sings "Million Dollar Bash". Silent footage of a little boy capering to a record follows, at such length the innocent charm is squeezed from it, a characteristic misjudgement tonight.

Showing the surfeit of riches back-stage, Miranda Richardson wanders on to read some Blake (Tilda Swinton does the honours later). Then Patti Smith appears, to try to kick-start things in style. In her fifties, she looks like a grey-maned street urchin, still with most of the band that drove her on as one of New York punk's first voices in the '70s. Singing "Birdland", from her debut Horses , she plugs right into this occasion's themes, mentioning fathers, sons, abandonment and peeled vision, her own words suggesting Blake's. But when she attempts incantatory ascension, pumping her fists and speeding her voice till words are smashed together, she flops back to earth. And earth-bound is where we then stay.

Billy Bragg, breathlessly en route to his own Meltdown gig, lightens the mood with Woody Guthrie's children's song "I Woke Up in a Dry Bed", a rite of passage that unsurprisingly fails to spark a singalong. Eliza Carty then lends her vaulting voice to a folk song about a woman burying her late child husband in the soil, suggesting the deep rhythms of fertility and decay that underlie youth. Beth Orton soon follows with another Guthrie song, "Don't Push Me Down". Her voice invests its lyrics with the fragile, gathering strength of an essentially helpless child standing up for herself, the sort of sentiment rock's concentration on angry adolescence forgets. Film footage of children in a street market, lost in their own worlds, adds to this moment of revelation, before Tori Amos explodes on to the stage. Sweeping to her piano in a diaphanous cape, she squats on its stool, legs braced as if ready to run right through it. Private groans, growls and roars punctuate a set starting with "Silent All These Years". Tossing her red mane back, saying nothing, she is extreme and initially magnetic. One nod to Blake aside, though, she blanks the night's wider themes, unless you accept Sinead O'Connor's woolly contention later that "we're all children, really". The feminine bias of the bill, like Amos's set, suggests a confused infantilising of women which was surely not Smith's intention. The vastly under-rated Yoko Ono then essays some gutteral yelps of her own on "Rising", to sadly dated effect, and some giggles. It's left to ex-James man Tim Booth to inject pop passion. Singing "Sit Down" for the first time in years, he refinds this Madchester anti-anthem's meaning as a hymn to ordinary adolescent madness. Marianne Faithfull, after reading Blake's startling "The Little Black Boy", musically massacres Lennon's "Working Class Hero", while letting its lyrics' cold fury burn through. Kristin Hersh then sweetly inhabits the male murderers and female victims of Appallachian folk tunes, before Sinead O'Connor lets the hard notes of her songs hang in the air, in an evening of exceptional vocalists.

A ragged, cast-assembling finale sees O'Connor and Ono in a deep hug of sisterhood. But there have been no such historic musical moments. It's been too unfocused, for far too long, plain and bitty gruel that leaves me flat. Blake's name, and Smith's, deserve fierier fare than that.

Festival events run until 26 June