Having moved seamlessly between its first two components, Nine Rivers enters an entirely new area with its third piece, Viriditas. A work for 16 voices, it was commissioned for the BBC Singers, who gave the first performance in Brussels in early 1994. The word ‘viriditas’—Latin for ‘greenness’—has an interesting provenance, its strongest association being with Hildegard of Bingen, for whom it was a deeply inspiring concept, ubiquitous in her writings. Fragments of Hildegard’s poetry are one of four textual sources used in the piece, together with an “early 16th century alchemical paraphrase of the Latin mass by the German alchemist-astrologer-priest Nicholas Melchior of Hermannstadt” (better known today as Melchior Cibinensis), an extract from a Marian hymn attributed to Albertus Magnus and an “anonymous Hebridean ‘weaving’ song or incantation”, this last being in Scots Gaelic, and as such the only non-Latin text Dillon has used. Inspirationally speaking (Dillon doesn’t set it to music), the relevant stanza from Rimbaud’s Le Bateau ivre is this one:
I have dreamed of the green night with dazzled snows,
A kiss slowly rising to the eyes of the sea,
The circulation of unknown saps,
And the yellow and blue awakening of singing phosphorous!
(translation by Wallace Fowlie)
Timbrally disjunct from its predecessors, Viriditas also stands apart from them in the complexity of its material. The opening moments are relatively straightforward, but they’re immediately answered by a taut passage in which individual voices already start to grow indistinct. There’s the sense of a fundamental layer moving slowly, far below, while the upper voices skitter and slide over a more mobile surface. Slowly, the texture clarifies, and strands and fragments of quasi-tonal (even pastiche) material protrude through; in tandem with this, the voices become united, the sopranos and altos continuing to chant and glissando over the slower underpinning. After a time they all fragment again, reciting their own concerns intently, repeating words and phrases (there’s an almost ritualistic quality to the choir’s demeanour), voices occasionally grouping together. The upper voices then fall silent, the men coalescing onto the bare interval of a 5th, both notes undulating, overlapping each other; the women return, singing similarly to before, and there’s a brief sense of 4-part polyphony before the lower voices now briefly depart. At their return—tenors first then basses—the simple melodic movement with no large leaps gives the music a chant-like quality.
Arriving at the middle of the piece, there’s a short pause (momentary silences of this kind are becoming regular and significant in Nine Rivers), whereupon Dillon embarks on a latter half much more convoluted than all that’s gone before. The choir resumes loudly following the hiatus, with lyrical lines spiralling out from the close-knit group texture. The voices thin and quieten, dwindling to just a few slowly-moving lines, before erupting again in wild ululations. There now follows a lengthy episode formed around a rich, tightly-packed cluster, individual parts very hard to discern, and as it develops, repeated pitches become audibly important, at first with the men, who grow fiery on their single note. Dillon once again breaks things up, switching to a gorgeous soprano duet that starts to trill and twitter as a tutti swiftly expands beneath them. This leads to the second highly dense episode, again hard to unpick; only now there’s a sense of culmination, multiple texts uttered simultaneously in a kind of verbal stretto. One last time, Dillon breaks the surface tension, dissolving the choir to leave just a few voices on a spare chord. Growing into a final chorus, the music concludes over a long pedal note, the final chord deliciously inscrutable.
The performance of Viriditas at last year’s world première of Nine Rivers was given by the work’s dedicatees, the BBC Singers, conducted by Simon Joly. i’ve heard it said many times—by both composers and singers alike—that the homogeneity of the BBC Singers is both a blessing and a curse, capable of subverting a composer’s voice and replacing it with a more generic sonic identity. However, in a work of such uncommon invention as Viriditas, Dillon’s unique voice is unmistakable, and the BBC Singers’ performance is superbly immersive.