Imagine a phantom alternative cut of Velvet Goldmine where those stack-heeled gawky glam fans rampage through the streets of London only?through a succession of exquisitely wrong turns?to find their soaring pretensions have lifted them right out of their recessive spacetime into some hi-fi, sci-fi, cybernetic plaza of tranquillity from Logan’s Run. That’s the kind of speculative leap you might make in mapping these four ’70s transmissions from the brain of Eno. Examiners of 2040 will ask the question: “How did Eno get from Bryan to Byrne to Bono, from the feathered, jangled psycho-stomp of ‘Needles In The Camel’s Eye’ to the becalmed anxiety of ‘Spider and I’ in the four short years between 1973 and 1977?” And this quartet add up to some sort of answer.

They’re a fab four. In which case Warm Jets is Paul (bitterly sentimental, discreetly avant-garde), Tiger Mountain is John (sentimentally bitter, avantly discrete), Green World is George (beguilingly enigmatic with a lunatic fringe) and After Science is Ringo (muscular but lumpy). Or they’re a fantastic four (in which case they are, respectively, The Human Torch, Mr Fantastic, The Invisible Girl and The Thing).

Received wisdom would have it that these lyrical excursions are the surfacing for air during the long breaststroke into the pool of ambience, figurative gasps that intersperse the more abstract deep-sea research. But, for some of us, these records mark the full flowering of Eno?the man who once aspired to become a tape recorder?as supreme pop collagist.

Here Come The Warm Jets (1974), the first fractured flush of Eno’s freedom from a Roxy he feared fatally compromised, offers a template of the kind of collage we have in mind. “Cindy Tells Me” suggests members of the Bloomsbury Group forming a VU tribute band and trying their hand at Venusian doo-wop. Or “Blank Frank”: Bo Diddley inventing the Pixies 30 years too soon.

This sensibility is perfected on Taking Tiger Mountain (also 1974)?not through anything as dull as coherence, but through an anxious rightness: what David Lynch once described as “the eye of the duck”, an exact oddness, right on the nailhead. It’s perversely tempting to celebrate it as a great lyrical achievement: Eno has done more than anyone to bring us round to the pleasures of texture over text, perfume over persona (and I could write another thousand words on Mackay’s sinister sax arrangements, Manzanera’s splintered fretting). But on songs like “Back In Judy’s Jungle” (Lewis Carroll and Philip K Dick have a stab at rewriting “It’s A Long Way To Tipperary”) or “The Fat Lady Of Limbourg” (Bill Burroughs drafts a ballad for Bj