Volcano continues in the same vein of juxtaposition of violent and calm (with the opening tempo mark amusingly, calmissimo) seen in the 4th Symphony and Energy to some extent; however, it is significantly more violent (appropriately, given the title), and features the percussion to a much greater extent (notice that before Energy and the 4th Symphony, there has been very little use of percussion from Simpson other than timpani).
It’s worth noting here that Volcano comes at the end of a very productive decade for Simpson. Its predecessor, written at the same time as the 4th Symphony coming 8-years prior. In the meantime, Simpson had completed three more Symphonies and five Quartets, including the three, 40-minute long ‘Rasumovskys’, making Volcano very much a late-mid period work, coming just 2 years before the 8th Symphony.
It is a rare example of a programmatic title, although later there are a couple of other examples in the brass band music, but none quite as descriptive as this depicting a volcanic eruption. This may be true, but as a listener it is still quite abstract and difficult to attribute a concrete story to the music, which one would expect to be able to do with purely programmatic music. It can be seen more as a natural process. This is not unique among Simpson’s structure either. The 6th Symphony depicts life growing from a cell into a grown individual.
The opening of Volcano is not unlike that of Energy. In fact, the two works very clearly demonstrate the development of the composer’s ability to write for the ensemble, Volcano taking far more risks and as mentioned before, introduces a far greater array of percussion. Perhaps it is easier to justify the use of purely timbral instruments in a programmatic work? Regardless, the result is a much more turbulent and immediately exciting piece compared to the logical and organic growth of Energy. Volcano continually peaks and troughs, each time more violent than the last until the eruption is over and stillness returns at the end.