Prokofiev was a child of the industrial age and his overlay of imagery on the underlying sonata-allegro base seems born of the age in which he lived. At the start one might imagine a great whirling machine awaiting its load. But later, when load is applied, the hungry yet massive gears grind slower. At other times they spin joyously in unimpeded anticipation. There is the roaring and clanking of metal on metal when the moment arises and then the roaring up into the renewed pleasure of its task.