Partway through the song, the lyric "the sun is in the east, even though the day is done" refers to the glowing fireball of a nuclear explosion.
Session drummer Andy Newmark plays drums on this song, as Pink Floyd drummer Nick Mason was unable to perform the song, due to its complex time signature changes. The song begins and ends in 9/8 time, while the majority of the song is in 4/4 (or "common time"), and it is punctuated with added measures of 7/8 and 3/8. Adding to the complexity, the main theme of the rhythm guitar has chords changing emphatically in dotted eighth notes, so three eighth-note beats are divided equally in two. This is not unlike what "Mother", from the previous Pink Floyd album, The Wall, does, and on that song, Mason relinquished the drumming duties, in that case to Jeff Porcaro.