Pink Floyd

This is the single that preserves most vividly the brief heyday when Barrett led the band. In a song that addresses a girl in a fairy-tale voice, Barrett's dizzying imagination, soon to crumble, already flashes through.

• The song opens with Wright's Farfisa organ. The thin, sharp tone of the Italian electric organ captures the very color of London's underground scene in 1967.
• Barrett's guitar spreads like ripples through a Binson Echorec (a delay unit), which records sound onto its own drum and plays it back. Listen for the guitar that slides and pours down between the verses.
• The short phrase that suddenly speeds up in the middle section is said to have been made by changing the tape speed. For a few seconds, a moment passes like a toy box turned upside down.
• Within a length of under three minutes, a nursery-rhyme melody and dizzying sound effects coexist. Heard alongside "Interstellar Overdrive," the long improvisation from the debut album of the same year, it reveals Barrett's two faces.

This is the song in which the post-Barrett band first found its own voice. The fragment-splicing method of the searching years was perfected into a single 23-minute flow, and it is also where Waters first took hold of the theme of empathy.

• The sonar-like ping of the opening was made by Wright sending a single piano note through a rotating speaker (a Leslie speaker). That one note opens the ocean of the entire piece.
• In the first verse, Gilmour and Wright sing the same melody together. Their voices overlap to create a soft texture, as if they were not one person.
• From around the seven-minute mark, Waters's bass and Mason's drums lay down a dancing, repetitive rhythm (groove), over which Gilmour's solo unfolds. It is the passage on the album that most moves the body.
• The seagull-like cries heard in the eerie middle section around the eleven-minute mark are a sound Gilmour said he stumbled upon by connecting a foot-operated device that opens and closes the tone (a wah-wah pedal) backwards.
• Compare it with the performance in the Pompeii amphitheater concert film. On a stone stage without an audience, the piece is played in two parts, ringing rougher and wider than the studio version.

A concept album that weaves time, money, death and madness into a single flow. Designed to run without gaps between songs, it was made to be heard in one sitting, from beginning to end.

• The album begins with a heartbeat and ends with a heartbeat. Every sound in between is arranged as though it were happening within a single human life.
• "Time," the song on the video card, opens with dozens of clocks chiming all at once. Parsons had recorded the sound at an antique clock shop as a stereo test, separately from the album. Then Mason strikes, one by one, small tunable drums (rototoms).
• "Money" begins with the sounds of coins and a cash register spliced together in a tape loop. Note the moment when it flows in an unusual meter of seven beats to the bar and then shifts to four for Gilmour's guitar solo.
• In "The Great Gig in the Sky," Torry's wordless voice soars and collapses above Wright's piano. It is a way of singing about death without words, through emotion alone.
• The murmuring voices heard between the songs are answers drawn from studio staff and people around them by showing them question cards. Unscripted voices of real people, they are all the more chilling.

A song dedicated to the departed Barrett. Without reproach, it addresses him in the tone of someone asking after an old friend — and on the day they were refining it, Barrett appeared in the studio.

• The mysterious chord that stretches out at the very beginning is said to have been built on recordings of wet wine-glass rims being rubbed, layered together. Above it, Wright's synthesizer slowly rises.
• Around four minutes in, the four-note motif Gilmour plays on guitar, one note at a time, is the heart of the piece. They were four notes Gilmour happened to play, and the members are said to have thought of Barrett in the loneliness of that melody.
• Parts I through V sit at the very start of the album and VI through IX at the very end, framing the whole record. Running to 26 minutes when combined, the form itself looks like a frame built around an absence.
• At the end of Part V, Dick Parry's saxophone enters. As a wind instrument like a human voice comes into a piece led by guitar, the mood grows warmer still.

This is the passage in which the protagonist of The Wall adds one more brick at school. At the heart of the telling stand the voices of children rising up against an oppressive education.

• At producer Bob Ezrin's suggestion, the drums took on the steady, metronomic beat of the disco then in vogue. Mason's spare hi-hat and Waters's solid bass lay down a floor fit for dancing.
• The second verse is sung by pupils from Islington Green School in London. An engineer went to the school to record them, and their voices were layered many times over until they sounded like a great choir.
• Gilmour's solo after the chorus is said to have been played on a Gibson Les Paul. Its tone, coiling and viscous rather than sharp and piercing, stands in contrast to the cold rhythm.
• At the song's end, the shouting of the classroom and the noise of the playground overlap as it passes into the next track. It is the moment that reminds us this song, before it was ever a stand-alone single, was one scene in a long story.

A song about the protagonist losing all feeling, shut up inside the wall. It is counted as the summit of the two men's collaboration, where Gilmour's melody and Waters's lyrics interlock most deeply.

• The song's skeleton came from a demo Gilmour had made for a solo album, and Waters set words to it. Two very different sensibilities meet within a single song.
• Waters sings the verses, low and dry; Gilmour sings the choruses, warm and high. Listen to it as a dialogue between a cold voice calling from outside and a distant voice answering from within.
• The second solo that closes the song, Gilmour has recalled, was pieced together from the best parts of several takes. He is said to have run his Fender Stratocaster through a device that smears the sound and thickens it (fuzz).
• The strings flowing in the background were arranged by Michael Kamen. In the 1980–81 shows, Gilmour played this solo from atop the wall that had been built up on stage.

The closing track of The Division Bell, in which an aging narrator looks back calmly on youthful days spent in Cambridge. It is the song in which the band first sang of their own beginnings.

• A bell tolling steadily from beginning to end ties the song to the album's title. It sounds like a device quietly announcing that time is passing.
• Over a simple, repeating piano figure, Gilmour's voice begins low. The song's strength lies in its plainness, holding to a tone of remembrance without any flashy devices.
• The long solo in the latter half was played on a guitar laid flat across the lap and sounded by sliding a metal bar along the strings (lap steel). The notes glide from one to the next, drawn out long like weeping.
• Michael Kamen once again handled the string arrangement, as he had on The Wall. Listen all the way through those final minutes, as the solo ends and the sound fades away.