The performance begins before a note has been heard. Hands are washed in two adjacent basins. The rims of 37 “musical glasses”, housed in a rotating mechanism, are wetted. Only then can fingers be delicately applied to produce the desired notes.
Welcome to the sound of the glass harmonica. It produces a light, echoey timbre – subtler and more sophisticated than when you strike glasses filled with different levels of water. But beyond the visual effect, what is its musical value? The question hovered uncomfortably over the Hebrides Ensemble’s recital at the Edinburgh International Festival, featuring Thomas Bloch as soloist in two works for glass harmonica by Mozart and an arrangement of his Fantasia in F minor.
Some readers may recall the minor impact the instrument made in recent London productions of Lucia di Lammermoor, when the Royal Opera and English National Opera tried to follow Donizetti’s original idea of a glass harmonica in the Mad Scene. Mozart heard exponents in Milan and Vienna, but his Adagio in C minor K356/617a for solo glass harmonica disappoints not for its brevity – barely three minutes – but because the content is so slight. The Adagio and Rondo K617 has more substance – the argument alternating between soloist and a quartet of woodwinds and strings – and yet the impact is the same: the sound is so faint that it can’t compete. Even in Lyell Cresswell’s new arrangement of the F minor Fantasia (originally for mechanical organ), the musical substance lay with the five accompanying instruments while the glass harmonica diverted attention.
A concert for curiosity hunters? The rest of the programme suggested this was one of the Hebrides Ensemble’s less rewarding adventures. In each half Mozart was complemented by George Crumb (born 1929), whose Four Nocturnes occupied violin and piano on separate musical paths to no discernible purpose. As for his Vox Balaenae, inspired by the taped “songs” of humpback whales, pianist, cellist and flautist were required to wear black face-masks and variously sing, whistle and wail. Amid the humbug there were some brief, appealingly simple sounds but, as with the glass harmonica, the “story” surrounding the music always seemed bigger than the music itself.