Personally, I think it's how your mind makes its own natural rhythm for the lyrics as you read them, but the beat of the song is completely different. Dark Side of the Moon was released in 1973, and since then, has stayed in the Top 40 Bestseller list. I'll bet dollars to donuts that this will stay in the Top 40 Bestseller list for years to come. One incredibly unique aspect about this album is how every track is connected to each other. A few beats of silence in between the ending of one song and the beginning of the next is an idea that is unknown to Pink Floyd.
Every song is connected to the one after and before it, making a sort of audio-opera.
Really good poetry, too. Then, if you look in the album booklet, on the page after they give you the lyrics for Eclipse, there's a border on the bottom with a rainbow, but the green stripe of the rainbow jolts up and down, like the readout on a heart-beat monitor. There are some reviewers of this album that say it just isn't for some people. They could not be more wrong. Anyone with an open mind and an appreciation for good music will have a similar reaction to this album to mine.