Harrison's Clocks - for piano solo (1998)

Harrison's Clocks was inspired by Dava Sobel's book, Longitude, which tells the story of the eighteenth-century clockmaker John Harrison and his forty-year obsession with solving the longitude problem by inventing a clock that would keep perfect time at sea. Harrison sustained his single-minded and iconoclastic quest in the face of jealous opposition from the astronomical establishment. Between 1737 and 1760, he perfected four individual chronometers that finally enabled the time-into-space translation required for the precise measurement of longitude. These are now displayed at the national Maritime Museum in Greenwich, where the big sea clocks H-1, H-2 and H-3 are in perfect working order, while H-4 is a pocket watch kept in a state of suspended animation to protect its delicate mechanism.

Each of the five pieces begins with a pianistic signal in which a descending rush of low notes lands on the bottom A of the instrument.
Clock I presents a jabbed figure in contrary motion, suggesting a pendulum whose tick and tock are not always even. This alternates with a toccata in which staccato semiquavers in each hand are underpinned by held quavers that sometimes fall together and at other times are out of phase. An arc-shaped rush of notes, distinct from the opening signal but audibly related to it, articulates each sub-section of the episodic structure, which rises progressively higher in register.
Clock II (the first trio) is a mechanical free fantasy on the note E, twice interrupted by an 'alarm bell' of faster music.
Clock III is a mechanical fantasy in which six distinct musical figures, each one registrally and gesturally defined, act as the individual components of a single complex mechanism. The registral layering is constant and each component keeps within its own waveband. These figures are only ever heard two-at-a-time, but every possible combination of ideas within the six is used. The entry of a new idea in either hand always overlaps the continuation of a previous one in the other.
Clock IV (the second trio) is the only piece to literally repeat the opening signal, which here announces each of the four subsections. The piece is based on a ten-note chord (one note for each finger) that continually and almost imperceptibly changes by one or two notes, first in the right hand, then the left. This produces a kaleidoscopic shifting within the chord, evocative of individual bulbs switching on and off inside a light display. Alternating with these chordal passages is a rocking figure related to the uneven pendulum' in Clock I. Overall, the piece can be heard as a kind of composed decay.
Clock V is a toccata in which the right hand is an afterbeat of the left until the halfway point, where the relationship is reversed.

Each piece begins in medias res, and ends only because its clock-spring has wound down. The heart' of the clock may have stopped, but the music could go on for ever.