Infinity symbol in bookbinding to indicate that a book is printed on acid-free paper and will therefore be long-lasting. In modern mysticism, the infinity symbol has become identified with a variation of the ouroboros, an ancient image of a snake eating its own tail that has also come to symbolize the infinite, and the ouroboros is sometimes drawn in figure-eight form to reflect this identification, rather than in its more traditional circular form. In the works of Vladimir Nabokov, including "The Gift" and "Pale Fire", the figure-eight shape is used symbolically to refer to the Möbius strip and the infinite, for instance
The Sky Moves Sideways as the first two LPs of the prior vinyl release, except for a 22-minute version of "Moonloop" on side four. The album was generally well received. AllMusic praised it for "...continuing the excellence of "Up the Downstair" while achieving a new liquid sense of drama and overall flow.", specifically praising the track "Stars Die". Original European vinyl release 2004 Expanded remaster The Sky Moves Sideways The Sky Moves Sideways is the third studio album by British progressive rock band Porcupine Tree, first released in February 1995. "The Sky Moves Sideways" has been compared to Pink Floyd's "Wish You Were Here"