<P> Tom Lehrer's anthology Too Many Songs by Tom Lehrer, uses fake English tempo markings to humorous effect . For example, Lehrer specifies that the song "National Brotherhood Week" should be played "fraternally" or "We Will All Go Together" be played "eschatologically" (and "Masochism Tango" be played "painstakingly"). </P> <P> Tempo is not necessarily fixed . Within a piece (or within a movement of a longer work), a composer may indicate a complete change of tempo, often by using a double bar and introducing a new tempo indication, often with a new time signature and / or key signature . </P> <P> It is also possible to indicate a more or less gradual change in tempo, for instance with an accelerando (speeding up) or ritardando (rit., slowing down) marking . Indeed some compositions - for instance, Monti's Csárdás or the Russian Civil War song Echelon Song - are mainly composed of accelerando passages . </P> <P> On the smaller scale, tempo rubato refers to changes in tempo within a musical phrase, often described as some notes' borrowing' time from others . </P>

Accelerando is a term indicating that the tempo is