“Pow R. Toc H.” is a mostly instrumental piece that does feature vocals but no lyrics. The track makes use of mouth sounds, somewhat resembling what would later become human beatboxing.

Toc H. was the army signallers' code for “TH”, representing Talbot House, a club where officers and enlisted men were equals, which later became an interdenominational Christian fellowship organization serving the community. (The emblem of Toc H. is an oil lamp, so a “power Toc H.” would be an electric torch–probably with a dim bulb, as per the saying “as dim as a Toc H. lamp”.)

According to Nick Mason, the original four members of Pink Floyd (Syd Barrett, Roger Waters, Richard Wright and Mason) were present at Abbey Road Studios and watched the Beatles record “Lovely Rita” from Sgt. Pepper’s Lonely Hearts Club Band.[4] Voice effects and noises similar to those used in “Lovely Rita” could be heard in “Pow R. Toc H.”, recorded in the next studio during the same period.

These kinds of mouth noises would appear again at several points of the band’s Waters-led history, from “Careful With That Axe, Eugene” to “Pigs (Three Different Ones)”, and most notably on “Several Pieces Of Small Furry Animals Gathered Together In A Cave And Grooving With A Pict”

The actual instrumental part of the song is widely jazz-oriented, which is not a very common ambience in Pink Floyd’s discography. However, jazz has proven to be a structural influence of many of the band’s long tracks featuring meaty improvised middle segments.