Before he started making avant-garde elevator music, Brian Eno released four of the most richly satisfying rock albums of the 1970s, all of which Virgin has taken it upon themselves to reissue recently. That Another Green World is, in my opinion, the least substantial of the four should not deter you one iota from acquiring it along with the other three, if for some benighted reason you don’t already have them.

Retreating from the extended suites and delightful lyrical nonsequiturs of Taking Tiger Mountain, Eno devotes much of Another Green World to instrumental squibs. Some have a lot of busy bass playing: “Over Fire Island” features some Jamaaladeen Tacuma-esque riffing over a synth noodle and a metronomic beat from Phil Collins (in what would be his last cool gig until he sat in with Zeppelin at Live Aid), while the mostly vocal-less “Sky Saw” drops in some slippery funk between crunching chords. Others are ambient, ominous journeys to nowhere: at the heart of the album are the title track, “Sombre Reptiles”, and “Little Fishes”, joined together to form a minimalist trilogy of tedium: tickling, echoing piano or long sustained guitar notes set against droning organ backdrops, with some warbling noises here and there (billed in the credits as “unnatural sounds”) to present the illusion of melody. These are meticulously soothing, with an almost sinister capacity to mesmerize a listener: they would be the ideal masking music for a series of subliminal messages. “In Dark Trees” and “The Big Ship” feature a primitive drum machine gone a bit haywire with sweeping organ washes, while “Zawinul/Lava” is monumental, dawn-of-civilization stuff complete with monkey cries and bird calls that would have worked wonderfully on the Quest for Fire soundtrack. Most trying of all is “Becalmed,” three-and-a-half minutes of anti-melodic somnambulism.

They are all extremely abstract, open invitations for some entirely speculative pronouncements regarding what they are meant to evoke. They seem like those captionless illustrations you see at the bottom of columns of text in The New Yorker: innocuous and easy to miss, they still serve to shape the way you absorb what you’re reading. Spatial metaphors for these instrumentals are inviting, partly because the geometric/figurative cover art—a layering of sheer planes of color on top of one other to create the illusion of a musician performing for an audience—suggests them. Something similar is happening in Eno’s painterly approach on these instrumentals: they are constructed through an accumulation of effects, with highlights daubed in here and there. Their lack of structure and their static rhythms, too, encourage one to think of them in terms of space rather than time; they reveal themselves the same way good paintings do, gradually, without any fanfare, only after an extended period of devoted concentration.

But the instrumentals aren’t really the reason to listen to this album. The four songs with actual sets of lyrics are; not because the words are especially compelling (though they are quite movingly straightforward, in a remarkable change of pace from his previous solo records) and not because Eno is an especially gifted singer (though he sounds as comfortable here as anywhere), but because the presence of lyrics forces Eno to structure the songs to accommodate them. Consequently, these songs feel complete, fully fleshed out, taking the ideas tested out in the instrumentals and making proper use of them, fulfilling their promise. The stately “Golden Hours” would have been other open-ended experiment without the words, which make Eno’s “choppy organs” (to again cite the credits) less tentative and more authoritative. Robert Fripp also contributes two of his best guitar solos on “St. Elmo’s Fire” and “I’ll Come Running,” all the more compelling for how restrained they are. And “Everything Merges with the Night” perfects the brooding, ruminative mood that dominates the album, and transcends it, transforming it into something truly rhapsodic, the way the heaviest tranquilizers can be.

Bonus pedantry: This reissue features an egregious typo on the back cover; giggle over it with your copy-editor friends.