"Locomotive Breath" is a song by British progressive rock band Jethro Tull from their 1971 album, Aqualung.

Written as a comment on population growth, "Locomotive Breath" was meant to replicate the chugging rhythm of a train.

It was about the runaway train of population growth and capitalism, it was based on those sorts of unstoppable ideas.

You'd think population growth would have brought prosperity, happiness, food and a reasonable spread of wealth, but quite the opposite has happened.

All of these recordings were then overdubbed onto each other because Anderson was finding it difficult to communicate his musical ideas about the song to the other band members.

Anderson explained the recording process of the song in an interview, saying "'Locomotive Breath' was actually an utter failure when we tried to play it all together.

And then we had something that was beginning to sound a bit like a song and it had that kind of metronomic feel, which I wanted it to have, because it's about a railway train running on the tracks.

Ian Anderson ranked "Locomotive Breath" as one of his top 10 Jethro Tull songs.

"[11] Ultimate Classic Rock named the song Jethro Tull's third best, saying, "This tune covers the length and breadth of Anderson’s songwriting talents, beginning with a bluesy John Evan piano intro so discreet one can barely hear it at times, before crashing into some of the most bombastic hard rock display of the band’s career.